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Wang J, Zhou Y, Wen H, Levitan IB. Simultaneous binding of two protein kinases to a calcium-dependent potassium channel. J Neurosci 1999; 19:RC4. [PMID: 10234050 PMCID: PMC6782707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
Large-conductance calcium-dependent potassium channels are subject to modulation by protein kinases, phosphatases, and other signaling proteins, and it has been inferred from electrophysiological experiments that signaling proteins sometimes can be intimately associated with these channels in a regulatory complex. We show here that endogenous protein kinase activity coimmunoprecipitates with both native and recombinant Drosophila Slowpoke (dSlo) calcium-dependent potassium channels. Coimmunoprecipitation experiments using antibodies against several protein kinases demonstrate that dSlo can bind simultaneously to the Src tyrosine kinase and to the catalytic subunit of the cAMP-dependent protein kinase (PKAc). Both kinases can phosphorylate the channel in Drosophila heads and in heterologous host cells. The PKAc binds directly to a 172-amino acid region in the C-terminal domain of dSlo, without the intervention of regulatory subunits or anchoring proteins, and channel phosphorylation by PKAc is not required for this binding interaction. In contrast, several phosphorylatable tyrosine residues in dSlo are important for Src binding. The results are consistent with the idea that an ion channel can act as a scaffold for its own specific set of modulatory enzymes.
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152
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Yang Y, Wen H, Mattay VS, Balaban RS, Frank JA, Duyn JH. Comparison of 3D BOLD functional MRI with spiral acquisition at 1.5 and 4.0 T. Neuroimage 1999; 9:446-51. [PMID: 10191173 DOI: 10.1006/nimg.1998.0422] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In order to investigate the merit of high field strength for BOLD-contrast-based functional magnetic resonance imaging (fMRI) studies, multishot gradient-echo fMRI experiments during motor cortex activation were performed on 1.5- and 4.0-T scanners with equivalent hardware, on the same volunteers. In these studies, artifactual vascular enhancement related to inflow effects was minimized, and large brain areas were covered by using a 3D scan technique. Temporal signal stability was optimized by using spiral readout gradients. The sensitivity for detection of activated regions was assessed by measuring the number of "activated voxels" and their average t score in predefined regions of interest. When comparing fMRI experiments with the same total scan time, performed on six subjects, and with acquisition parameters optimized for each field strength separately, the 4.0-T scanner proved to give superior results, with a 70% greater number of activated voxels and a 20% higher average t score for the activated voxels.
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153
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Chen J, Liao W, Wen H, Wu J, Yao Z. A comparison among four regimens of itraconazole treatment in onychomycosis. Mycoses 1999; 42:93-6. [PMID: 10394855 DOI: 10.1046/j.1439-0507.1999.00404.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The purpose of this study was to compare the efficacy of different dosage regimens in the management of onychomycosis with itraconazole and to determine the results of a further 1-week intermittent pulse treatment in non-cured patients. In this study, 153 patients were randomly allocated to four groups. Patients in group A were treated with daily doses of 100 mg for 3 months in the case of fingernail onychomycosis and for 4 months in the case of toenail onychomycosis. Patients in the other groups received a intermittent pulse therapy, in which the drug was taken for 1 week, then discontinued for 3 weeks, three cycles for fingernail and four cycles for toenail infection. The daily doses were 400 mg (group B), 300 mg (group C) and 200 mg (group D). After therapy, non-cured patients were treated further with one cycle in which the daily dose was 400 mg. Patients were subsequently observed for 9 months and efficacy was assessed by mycological examination and the growth of unaffected nails. At the end of the therapy, the cure rates in the four groups were 19.1% (A), 15.2% (B), 18.9% (C) and 17.9% (D), and no significant differences were found between each of B, C, D and A. At the end of the study, the cure rates were 76.2%, 91.3%, 78.4%, 28.6% respectively. The group that received further treatment had a cure rate of 55.6% at the end of the first month and of 83.3% in the second month. Drug tolerability was equally good in the four groups. Intermittent pulse therapy with a daily dose of 400 mg had the highest cure rate. Treatment of improved but non-cured patients with a dose of 400 mg intermittent pulse therapy markedly increased the cure rate. All treatment regimens were well tolerated.
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Yan L, Wen H, Wei X. [Granulomatous trichophytosis rubrum. Report of 2 cases]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 1999; 22:556, inside back cover. [PMID: 10073010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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155
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Wen H, Nagelhus EA, Amiry-Moghaddam M, Agre P, Ottersen OP, Nielsen S. Ontogeny of water transport in rat brain: postnatal expression of the aquaporin-4 water channel. Eur J Neurosci 1999; 11:935-45. [PMID: 10103087 DOI: 10.1046/j.1460-9568.1999.00502.x] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Brain water transport is poorly understood at the molecular level, and marked changes occur during brain development. As the aquaporin-4 (AQP4) water channel protein is abundant in brain, the expression levels and subcellular distribution of this protein were examined during postnatal development. This study focused on the cerebellum, which showed the same pattern of AQP4 development as the rest of the brain. Semiquantitative immunoblotting revealed very low levels of AQP4 in the first postnatal week. A pronounced increase was noted in the second week, from 2% of adult level at postnatal day 7 (PN7) to 25% at PN14. At PN1 and PN3 immunofluorescence microscopy revealed weak labelling, mainly in radial processes (Bergmann fibres) and at the pial surface. Between PN7 and PN14 the labelling underneath the pia showed a strong increase, and immunoreactivity also appeared around blood vessels throughout the cerebellum. High-resolution immunogold electron microscopy revealed that the subpial and perivascular labelling was restricted to glial end feet, notably to those plasma membrane domains that were apposed to the basal laminae. At no stage was there any evidence of neuronal AQP4 labelling, and AQP1, -2, -3 and -5 proteins were not detected in the neuropil. Riboprobes to AQP4 mRNA produced a particularly strong in situ hybridization signal in glial cells between PN7 and PN14, corresponding to the stage of the most rapid increase of AQP4 protein. The time course and pattern of AQP4 expression suggests that this aquaporin plays an important role in brain water and K+ homeostasis from the second week of development.
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156
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Aletras AH, Ding S, Balaban RS, Wen H. DENSE: displacement encoding with stimulated echoes in cardiac functional MRI. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 1999; 137:247-52. [PMID: 10053155 PMCID: PMC2887318 DOI: 10.1006/jmre.1998.1676] [Citation(s) in RCA: 354] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Displacement encoding with stimulated echoes (DENSE) was developed for high-resolution myocardial displacement mapping. Pixel phase is modulated by myocardial displacement and data spatial resolution is limited only by pixel size. 2D displacement vector maps were generated for the systolic action in canines with 0.94 x 1.9 mm nominal in-plane resolution and 2.3 mm/pi displacement encoding. A radial strain of 0.208 was measured across the free left ventricular wall over 105 ms during systole. DENSE displacement maps require small first-order gradient moments for encoding. DENSE magnitude images exhibit black-blood contrast which allows for better myocardial definition and reduced motion-related artifacts.
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157
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Wen H, Lin S. [Renal protective effect of valsartan in diabetic rats]. ZHONGHUA NEI KE ZA ZHI 1999; 38:157-60. [PMID: 11798641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To investigate the mechanism of valsartan in protecting the renal lesion of diabetic rats. METHODS The following groups of rats were studied: normal control rats, streptozotocin diabetic rats and diabetic rats treated with valsartan (8 mg x kg(-1) x d(-1)). Mean arterial pressure, plasma glucose, serum insulin, serum creatinine, urinary albumin, ACE activity and Ang II concentration of kidney as well as profile of kidney hypertrophy were observed after 2, 4, 8 weeks of treatment, while TGF beta(1) mRNA expression of kidney cortex was assessed by Northern blot analysis, TGF beta(1), fibronectin and collagen IV expression were measured by immunohistochemistry. RESULTS Serum creatinine level (P < 0.05), urinary albumin excretion and kidney hypertrophy index (P < 0.01) of valsartan treated group were significantly lower than those of diabetic untreated group. There was a significant increase in mRNA expression of TGF beta(1) and protein expression of of TGF beta(1) fibronectin and collagen IV in diabetic rats (P < 0.01). The expression of TGF beta(1) mRNA and protein (P < 0.01) as well as the protein expression of fibronectin and collagen IV (P < 0.05) in the valsartan group were much lower than that in the diabetic group. CONCLUSION The results suggested that valsartan has some renal protective effect on diabetes in rats, partly through down-regulating TGF beta(1) expression and reducing deposition of glomerular ECM.
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158
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Wen H, Li W, Peng G, Chi Y. [Content variety of alisol B 23-acetate in Rhiozma Alismatis reaped at different time]. ZHONG YAO CAI = ZHONGYAOCAI = JOURNAL OF CHINESE MEDICINAL MATERIALS 1998; 21:595-6. [PMID: 12569673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Alisol B 23-acetate in Rhizoma Alismatis reaped at different time was determinated by RP-HPLC. The result indicated that the content of those reaped in April is obviously higher than those reaped from Jan. to March.
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159
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Wu H, Wen H, Guo R, Ye D. [Effect of ginger-processing on the contents of guanosine in Pinelliae rhizoma (banxia)]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1998; 23:661-3, 702-3. [PMID: 11599344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
OBJECTIVE To compare the guanosine contents in various products of Pinellia Rhizoma processed by different amounts of ginger and alum. METHOD Using the technology of HPLC. RESULT The guanosine contents in the two products of Pinellia Rhizoma processed in line with the pharmacopoeial method and orthogonal method respectively are very close to each other and change every little as compared with raw Pinellia Rhizoma. But the contents in the products of Pinelliae Rhizoma processed in other ways (digged in alum solution or in ginger Juice decocted with ginger juice, etc.) are much less than those of raw Pinellia Rhizoma. CONCLUSION There are no obvious differences in guanosine contents between Pinellia Rhizoma processed by orthogonal technology and Pinellia Rhizoma processed by pharmacopoeial method. Processing technology has considerable influence on the water soluble components of Pinellia Phizoma.
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160
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Cohen H, Paolillo E, Bonifacino R, Botta B, Parada L, Cabrera P, Snowden K, Gasser R, Tessier R, Dibarboure L, Wen H, Allan JC, Soto de Alfaro H, Rogan MT, Craig PS. Human cystic echinococcosis in a Uruguayan community: a sonographic, serologic, and epidemiologic study. Am J Trop Med Hyg 1998; 59:620-7. [PMID: 9790441 DOI: 10.4269/ajtmh.1998.59.620] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
A prevalence and transmission study of human cystic echinococcosis (CE), due to infection with the dog tapeworm Echinococcus granulosus, was undertaken in the village of La Paloma in central Uruguay. The human population was registered and screened for CE by abdominal ultrasound scan as well as a number of serologic tests. Dogs were screened for E. granulosus infection by arecoline purgation as well as specific coproantigen testing. The total prevalence of human CE (new cases and those with a previous history) was 5.6% (64 of 1,149); 3.6% (40) of the cases were new ultrasound detected asymptomatic cases (mean age = 45 years). Age prevalence increased from 1.1% in the 4-6-year-old group to > 11% in the > 60-year-old group; the 20-29-year-old group had a significantly higher CE rate of 7.4%, compared with younger and older age groups, and there was no difference between sexes. A CE rate of 3.9% (20 of 514) was also recorded by ultrasound for new cases in the population residing outside the village. Most of the hydatid cysts were located in the liver presenting as either univesicular cysts or a solid mass, and of those 71% and 63%, respectively, with such cyst presentations were seropositive against E. granulosus cyst fluid antigens. Two of eight individuals who were filter paper blood spot seropositive, but ultrasound scan negative, were subsequently diagnosed respectively with pulmonary hydatidosis after radiography, and hepatic hydatidosis after computed tomography scan. Of 36 households with a CE patient, 32 were single cases while four households each harbored two CE cases. This did not represent a clustered distribution within families (23 of 117). Almost 20% of the dogs from La Paloma were found infected with E. granulosus after purge examination, with a mean worm number of 67 (range = 1-1,020). An additional eight dogs that were purge negative were Echinococcus coproantigen positive. The study showed that human CE is highly endemic in Uruguay, with one of the highest local prevalence rates in the world. Transmission appears to occur readily within well-developed towns, as well as on rural sheep ranches. Mass screening by ultrasound scanning with confirmatory serologic testing is an effective approach to case detection at the community level.
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161
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Wen H, Balaban R. Authors' Reply. IEEE Trans Biomed Eng 1998. [DOI: 10.1109/tbme.1998.720208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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162
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Wen H, Balaban RS. Ultrasonic imaging of the electroacoustic effect in macromolecular gels. ULTRASONIC IMAGING 1998; 20:288-97. [PMID: 10197349 PMCID: PMC3100654 DOI: 10.1177/016173469802000405] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The electroacoustic effect occurs in electrolytes and colloidal suspensions. It describes the phenomenon in which a voltage applied to the sample produces an acoustic signal or vice versa. The basic mechanism is that charged particles in the sample have various mobilities due to different masses and viscosities. Under an external voltage they respond differently to the electrical force. This results in an overall acoustic vibration. The electroacoustic effect has been the basis for many measurement tools of solutions and other materials. In this note a method to image macromolecular gel samples using the electroacoustic effect at ultrasound frequencies is presented. Radiofrequency electrical excitation produces ultrasonic signal due to spatial changes in the electroacoustic some amplitude of the sample, which is used to construct an image similar to ultrasonography. This method is demonstrated in agar gel and egg-white protein phantoms. The image contrast mechanism is also discussed.
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163
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Abstract
Hall effect imaging is a noninvasive imaging method that combines ultrasound with a strong magnetic field to investigate the electrical properties of tissue. Although technical development is at an early stage, its value for detecting or characterizing pathologies in the breast and other organs is promising. In vitro studies in the past showed that tissue electrical properties are closely related to its physiology and morphology. Hall effect imaging may become a new tool to study these electrical properties in the body and potentially provide unique diagnostic information.
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164
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Wiesler DG, Wen H, Wolff SD, Balaban RS. Reduction of field of view in MRI using a surface-spoiling local gradient insert. J Magn Reson Imaging 1998; 8:981-8. [PMID: 9702901 DOI: 10.1002/jmri.1880080429] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Herein is presented a method for suppressing the magnetic resonance signal to a controlled depth by applying a spatially heterogeneous spoiler field between the slice-select and readout pulses. Eliminating the signal from near-surface regions allows one to shrink the field of view without introducing aliasing artifacts, thereby decreasing imaging time over a smaller defined volume. A unique planar magnetic gradient coil was constructed to generate the spoiler field. Phantom and human subject studies showed that the signal can be suppressed to controlled distances of up to 90 mm from the coil, with modest requirements on power supplies, pulse sequences, and materials, and with no increase in imaging time.
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165
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Wen H, Wiesler DG, Tveten A, Danver B, Dandridge A. High-sensitivity fiber-optic ultrasound sensors for medical imaging applications. ULTRASONIC IMAGING 1998; 20:103-112. [PMID: 9691368 PMCID: PMC2892210 DOI: 10.1177/016173469802000202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
This paper presents several designs of high-sensitivity, compact fiber-optic ultrasound sensors that may be used for medical imaging applications. These sensors translate ultrasonic pulses into strains in single-mode optical fibers, which are measured with fiber-based laser interferometers at high precision. The sensors are simpler and less expensive to make than piezoelectric sensors, and are not susceptible to electromagnetic interference. It is possible to make focal sensors with these designs, and several schemes are discussed. Because of the minimum blending radius of optical fibers, the designs are suitable for single element sensors rather than for arrays.
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166
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Zhou HX, Wen H, Wang YH, Delattre P, Quere JP, Vuitton DA, Craig PS, Giraudoux P. Experimental susceptibility of Spermophilus erythrogenys to Echinococcus multilocularis. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 1998; 92:335-7. [PMID: 9713550 DOI: 10.1080/00034989859915] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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167
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Abstract
This paper presents a new imaging method based on the classical Hall effect (HE), which describes the origin of a detectable voltage from a conductive object moving in a magnetic field. HE images are formed using ultrasound imaging techniques in a magnetic field. These images reflect the electrical properties of the sample. To demonstrate the feasibility of this method, images of plastic and biological samples are collected. The contrast mechanism and signal-to-noise issues are discussed. Since electrical parameters vary widely among tissue types and pathological states, HE imaging may be a useful tool for biological research and medical diagnosis.
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Abstract
The aim was to evaluate efficacy and tolerance of a short-schedule treatment regimen using a small dose of itraconazole in pulse intermittently. The open study evaluated the pulse therapy consisting of monthly 1-week cycles of oral itraconazole 200 mg daily for 2-3 consecutive months in 42 patients with onychomycosis. After active therapy, patients were evaluated for a maximum period of 1 year. Twelve of 42 patients were considered as being clinically cured, 17 were markedly improved, 11 were improved and two were failures. A mycological examination at the final visit was performed on all patients. Thirty-five were negative and seven were positive. This short treatment was well tolerated, with no adverse reactions, and may offer a new option for treatment of onychomycosis.
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169
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Jaffer FA, Wen H, Jezzard P, Balaban RS, Wolff SD. Centric ordering is superior to gradient moment nulling for motion artifact reduction in EPI. J Magn Reson Imaging 1997; 7:1122-31. [PMID: 9400858 DOI: 10.1002/jmri.1880070627] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Echo-planar imaging (EPI) is sensitive to motion despite its rapid data acquisition rate. Compared with traditional imaging techniques, it is more sensitive to motion or flow in the phase-encode direction, which can cause image artifacts such as ghosting, misregistration, and loss of spatial resolution. Consequently, EPI of dynamic structures (eg, the cardiovascular system) could benefit from methods that eliminate these artifacts. In this paper, two methods of artifact reduction for motion in the phase-encode direction are evaluated. First, the k-space trajectory is evaluated by comparing centric with top-down ordered sequences. Next, velocity gradient moment nulling (GMN) of the phase-encode direction is evaluated for each trajectory. Computer simulations and experiments in flow phantoms and rabbits in vivo show that uncompensated centric ordering produces the highest image quality. This is probably due to a shorter readout duration, which reduces T2* relaxation losses and off-resonance effects, and to the linear geometry of phantoms and vessels, which can obscure centric blurring artifacts.
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170
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Wen H, Li W, Wu H, Qiu L. [Influence of processing on atractylenolide III content in Atractylodes macrocephala Koids]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1997; 22:662-3, 702. [PMID: 11243181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
The atractylenolide III content in different processed products of Atractylodes macrocephala was determined by HPLC. The result has shown that the content in the processed products appears higher than that in the crude herb, with the yellow-fried product being the highest.
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Abstract
Cystic echinococcosis has been recorded in 21 out of China's 31 provinces, autonomous regions and municipalities (approximately 87% of territory). It constitutes one of the major public health problems, especially in several northwestern provinces and autonomous regions. This paper reviews the general situation, diagnosis, treatment, education and control programmes and international cooperation. Special attention is given to the Xinjiang, an endemic area about one sixth of the country's area with a human population of approximately 16 million.
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172
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Viviani MA, Wen H, Roverselli A, Caldarelli-Stefano R, Cogliati M, Ferrante P, Tortorano AM. Identification by polymerase chain reaction fingerprinting of Cryptococcus neoformans serotype AD. JOURNAL OF MEDICAL AND VETERINARY MYCOLOGY : BI-MONTHLY PUBLICATION OF THE INTERNATIONAL SOCIETY FOR HUMAN AND ANIMAL MYCOLOGY 1997; 35:355-60. [PMID: 9402529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Seventy-three Cryptococcus neoformans isolates and eight other yeast strains were studied. Fingerprints produced by priming with (GACA)4 differentiated C. neoformans from all other yeasts tested and identified the five C. neoformans serotypes. Four major bands of molecular size 800, 540, 475 and 410 bp were recognized for serotypes A, AD and D. Two of them were specific for serotype A and the other two for serotype D isolates. Serotype AD strains were identified by five different genotypic patterns in which at least one of the two bands specific for serotype A and D were present in different combinations. On repeated and simultaneously performed genotype and serotype testing of nine strains, the genotypic pattern did not change, whereas serotyping was unstable in three cases. PCR-fingerprinting using (GACA)4 as a primer proved more stable than serology in discriminating among C. neoformans serotypes A, D and AD and was able to distinguish among serotype AD strains.
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Wen H, Sun W, Guo Y. [The clinical and pathological characteristics of epithelial ovarian carcinoma in patients with age under 40]. ZHONGHUA FU CHAN KE ZA ZHI 1997; 32:548-51. [PMID: 9639757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To investigate the clinical and pathological characteristics of epithelial ovarian carcinoma in patients with age under 40. METHODS From Jan 1978 to Dec 1992, 54 cases with epithelial ovarian carcinoma under 40 years old were admitted to our hospital and enrolled in the study group, another 54 patients suffered from the same disease with age over 40 in the same period were served as control. Comparison analysis for clinical and pathologic data of 2 groups was performed using SPSS and SURVALC statistics software. RESULTS Main complaint because of either pelvic mass or abdominal mass found by chance was more common in study group (46.3%) than that in control group (27.8%). whereas because of symptoms was less common in study group (53.7%) than in control group (72.2%). Other parameters such as early stage (I and II) rate (61.1%), unilateral tumor rate (68.5%), average maximum diameter of tumor (13.6 cm), highly differentiated rate (50%) and the possibility for tumor reductive surgery were higher in study group than in control group. The difference of histological pattern and chemotherapy between 2 groups was not significant. Single variate analysis showed that the prognosis was better in study group. The 2-year and 5-year survival rates were 69.8% and 50.2% respectively. No recurrence was found in the 8 patients in whom the contralateral healthy ovary remained. However multiple variate analysis indicated that age was not a prognostic factor. CONCLUSION Epithelial ovarian carcinoma was prone to be lower degree malignancy in patients under 40 years therefore the prognosis of them was better. It might be resonable to have healthy ovary left in some select cases.
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174
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Liu G, Guo D, Zhong R, Yao Z, Wen H, He W, Hu W. [Determination on the glycosyl sequence of gypenoside A by TLC-FABMS]. ZHONG YAO CAI = ZHONGYAOCAI = JOURNAL OF CHINESE MEDICINAL MATERIALS 1997; 20:398-400. [PMID: 12572416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
The glycosyl sequence of gypenoside A (A) isolated from Gynostemma pentaphyllum Makino was determinated by TLC-FABMS. The gypenoside A was hydrolysed with cellulase and the hydrolysate showed eight spots on a TLC plate, and the FABMS analysis of these spots indicated they corresponded to gypenoside A, A-Rham, A-Glu, A-Rham-Glu, A-Rham-Glu, A-Glu-Glu, A-Rham-2Glu, A-Rham-2Glu in order. Two chains can be determined to be Rham-Glu, and Glu-Glu, respectively. So the glycosyl sequence of gypenoside A was identical of gypenoside XLIII.
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175
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Shambesh MK, Craig PS, Wen H, Rogan MT, Paolillo E. IgG1 and IgG4 serum antibody responses in asymptomatic and clinically expressed cystic echinococcosis patients. Acta Trop 1997; 64:53-63. [PMID: 9095288 DOI: 10.1016/s0001-706x(96)00637-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
IgG1 and IgG4 subclass antibody responses were investigated in two clinically different groups of hepatic cystic echinococcosis (CE) patients. One group consisted of surgically proven CE cases (clinically expressed hospitalized cases) and a second group comprised asymptomatic CE patients (first time community detected cases) diagnosed by portable ultrasound and serology in four different endemic communities. Fifty eight sera from surgically proven CE patients and 133 sera from asymptomatic ultrasound diagnosed CE cases were screened by ELISA using purified human hydatid cyst fluid antigen B for total specific IgG, IgG1 and IgG4 antibodies. Fifty sera from healthy individuals from within endemic regions were used as control negatives. Compared to control negatives total IgG antibody levels were elevated in both surgically proven (85%) and asymptomatic CE cases (77%) but there was no significant difference between the two groups. IgG1 subclass antibody levels were also elevated in both surgically proven (55%) and asymptomatic cases (58%) compared to endemic controls and similarly the difference in this response was not significant between these two groups. In contrast the prevalence of IgG4 antibodies in surgically confirmed chronic CE patients was greater (71%) than the respective IgG1 antibody levels (55%). The greatest difference in specific antibody response, between advanced surgically confirmed CE patients and ultrasound detected asymptomatic CE cases, was observed for IgG4 antibody levels which were detected in 71% of symptomatic compared to only 23% of asymptomatic patients (P < 0.0001). These observations confirm that IgG4 is an important diagnostic parameter for clinically expressed cystic echinococcosis in humans and suggest that a switch from a predominant IgG1 response to IgG4 might occur in CE patients as the disease progresses.
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Singerman RW, Denison TJ, Wen H, Balaban RS. Simulation of B1 field distribution and intrinsic signal-to-noise in cardiac MRI as a function of static magnetic field. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 1997; 125:72-83. [PMID: 9245362 DOI: 10.1006/jmre.1996.1073] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Two issues that pertain to the optimal static magnetic field for cardiac MRI were addressed: intrinsic signal-to-noise ratio (ISNR) and radiofrequency power deposition. From 1.5 to 9.5 T, proton Larmor frequencies of 63 to 400 MHz, numerical simulations were performed of the RF fields from a surface coil and a body coil loaded by a heterogeneous, three-dimensional, symmetric model of the human chest. The RF field distribution, the power required to produce the RF field, and the ISNR at the center of the heart were computed. The model was validated by comparison with experimental data up to 4 T. The RF field distortion was quantified and found to increase linearly up to 6 T due mostly to dielectric resonance modes. Body coil simulations beyond 6 T showed the onset of higher-order modes at the center of the heart. A range of expected RF power requirements was constructed as a function of field up to 9.5 T for surface coils and up to 6.8 T for body coils. Over this range of static field, ISNR for a constant coil geometry was bracketed by an upper limit that was slightly greater than linear with field and a lower limit that was slightly less than linear with field. The RF power and ISNR showed a strong dependence on chest thickness at 1.5 and 4.0 T. Additionally, independent of chest thickness, the model predicts a lower limit of a factor of 5 increase in RF power as the static field is increased from 1.5 to 4 T. Implications for imaging with other nuclei are discussed. Methods for checking the self-consistency of electrodynamic simulations are presented.
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Watson-Jones DL, Craig PS, Badamochir D, Rogan MT, Wen H, Hind B. A pilot, serological survey for cystic echinococcosis in north-western Mongolia. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 1997; 91:173-7. [PMID: 9307659 DOI: 10.1080/00034983.1997.11813127] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The seroprevalence of cystic echinococcosis in north-western Mongolia was determined in a cross-sectional study of 334 semi-nomadic pastoralists in their summer grazing areas. Overall, 5.2% of the subjects were found to be strongly seropositive for antibodies to Echinococcus granulosus antigen B by ELISA. Only 10% of the adult subjects (aged > or = 15 years) had heard of the disease and only 5% recognized hydatid cysts in their livestock (in contrast to the neighbouring province in China, where 76% had seen and recognized cysts in the organs of slaughtered animals). The close association between Mongolian pastoralists, their dogs and livestock is likely to encourage ready transmission of the parasite in a region where home slaughter is practised and offal for various scavengers, including domestic dogs. Further information is needed to determine the prevalence of infection in other intermediate hosts and in dogs and the clinical importance of the disease in this remote region.
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178
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Wen H, Sun W, Guo Y. [Prognosis and prognostic factor analysis epithelial ovarian cancer]. ZHONGHUA FU CHAN KE ZA ZHI 1997; 32:159-62. [PMID: 9596891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To investigate the prognosis change and prognostic factors of advanced epithelial ovarian cancer in recent over twenty years. METHODS One hundred and fourty patients with advanced epithelial ovarian cancer were analyzed. They were divided into two groups based on their operation time. 56 patients operated before Jan. 1980 were included in the first group, and the other 84 patients in the second group. Kaplan-Meier survival curves of the two groups were calculated, and Cox model was used to evaluate the prognostic factors of the disease at univariate and multivariate levels using SPSS and SURVCALC software. RESULTS There was no pathological difference in between the two groups, but the patients in the second group received more aggressive chemotherapy. The overall 1-, 2-, and 5-year survival rates were 61.2%, 32.1%, and 8.5%, respectively. In the first group they were 42.3%, 29.6% and 4.5% respectively and in the second group 69.3%, 36.2%, and 11.2% respectively. The prognosis of the patients in the second group was better than that in the first group, P < 0.05. Univariate analysis revealed that stage, grade, residual tumor size and chemotherapy were significant predictors of patients' outcome. COX regression analysis identified that they were all independent prognostic factors. The patients with advanced, low grade, residual tumor (> 2 cm) had poor prognosis. The prognosis of the patients who received equal or more than four, especially six cycles combined chemotherapy was improved. CONCLUSION The prognosis of the patients with advanced ovarian cancer has improved in recent over 10 years, higher optimal cytoreductive rate and equal or more than six cycles combined chemotherapy are important measures for the better prognosis of advanced ovarian cancer.
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Wen H, Denison TJ, Singerman RW, Balaban RS. The intrinsic signal-to-noise ratio in human cardiac imaging at 1.5, 3, and 4 T. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 1997; 125:65-71. [PMID: 9245361 PMCID: PMC2896425 DOI: 10.1006/jmre.1996.1072] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Cardiac imaging is inherently demanding on the signal-to-noise performance of the MR scanner and may benefit from high field strengths. However, the complex behavior of the radiofrequency field in the human body at high frequencies makes model-based analyses difficult. This study aims to obtain reliable comparisons of the signal-to-noise profile in the human chest in vivo at 1.5, 3, and 4 T. By using an RF-field-mapping method, it is shown that the intrinsic signal-to-noise increases with the field strength up to 4 T with a less than linear relation. The RF field profile is markedly distorted at 4 T, and the onset of this distortion is dependent on the body size. The high power deposition and the consequences of the RF field distortion are discussed.
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180
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Ito A, Wen H, Craig PS, Ma L, Nakao M, Horii T, Pang XL, Okamoto M, Itoh M, Osawa Y, Wang XG, Liu YH. Antibody responses against Em18 and Em16 serodiagnostic markers in alveolar and cystic echinococcosis patients from northwest China. JAPANESE JOURNAL OF MEDICAL SCIENCE & BIOLOGY 1997; 50:19-26. [PMID: 9354966 DOI: 10.7883/yoken1952.50.19] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Western blot analysis was carried out in order to evaluate new serodiagnostic markers, Em18 and Em16, for differentiation of alveolar echinococcosis (AE) from cystic echinococcosis (CE) using 36 serum samples from hydatid patients from Xinjiang, China, where AE and CE are both endemic and one double infection case has been reported. All AE cases except one (5/6) who exhibited a calcified lesion and a single case of double infection showed antibody responses against Em18 and Em16. Some of CE patient sera (6/22) showed antibody response against Em16 except one who showed that against Em18. Analyses of IgG subclass responses against Em18 and Em16 were carried out using all serum samples showing antibody responses against Em18 and/or Em16 (seven CE, five AE, and one AE + CE) and additional samples of three CE and 22 AE from Sichuan, China. IgG4 was the most predominant antibody subclass. Em18 and Em16 were recognized by both IgG4 and IgG1 (in most cases) or by either IgG4 or IgG1 (in minor cases) or by IgG3 (in very rare cases). Neither Em18 nor Em16 was recognized by IgG2 antibodies. The usefulness of Em18 and Em16 as potential new markers for serological differentiation of human AE and CE, respectively, is discussed.
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181
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Su Y, Wen H, Zhan G, Zou Z, Li Y. [Plasma and skin tissue endothelin in patients with psoriasis vulgaris]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 1997; 22:530-2. [PMID: 10072997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
Abstract
The levels of plasma endothelin in 46 patients with psoriasis vulgaris and the levels of endothelin in skin tissue of 25 cases were determined by RIA. The results showed that: (1) The plasma levels of endothelin in patients with psoriasis vulgaris was significantly increased compared with that of the controls (P < 0.01), so was the active stage group compared with the stable stage group (P < 0.01); (2) The level of endothelin in skin lesions of patients was significantly higher than that of the uninvolved skin. These findings suggest that endothelin might play a role in the pathogenesis of psoriasis vulgaris.
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Viviani M, Wen H, Roverselli A, Caldarelli-Stefano R, Cogliati M, Ferrante P, Tortorano A. Identification by polymerase chain reaction fingerprinting ofCryptococcus neoformansserotype AD. Med Mycol 1997. [DOI: 10.1080/02681219780001411] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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183
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You Z, Guo Y, Wen H. [Mutations of p53 gene exons 5 to 8 in human ovarian cancer and its clinical significance]. ZHONGHUA FU CHAN KE ZA ZHI 1996; 31:660-3. [PMID: 9387525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVES To detect p53 mutations in human ovarian cancer and to look for correlations between p53 mutation and clinicopathologic features. METHODS Mutations in exons 5-8 of p53 gene in 41 patients with primary ovarian cancer were screened by polymerase chain reaction-single strand conformation polymorphism analysis with non-isotopic silver staining method. RESULTS Mutations of p53 were found in 17 cases (41.5%); p53 mutation was not correlated with the age, the FIGO stage and the histologic type of the patients. However, it was associated with grade and lymph node metastasis in a univariate analysis. CONCLUSION Mutations of p53 occur commonly in human ovarian cancer. p53 mutation is an early event in ovarian carcinogenesis and may serve as a genetic marker for early diagnosis and prognosis.
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184
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Xu H, Wen H. [Clinical observing and nursing of the restoration after reconstruction defect of the front of foot]. ZHONGHUA HU LI ZA ZHI = CHINESE JOURNAL OF NURSING 1996; 31:519-20. [PMID: 9295520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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185
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Jaffer FA, Wen H, Balaban RS, Wolff SD. A method to improve the B0 homogeneity of the heart in vivo. Magn Reson Med 1996; 36:375-83. [PMID: 8875407 DOI: 10.1002/mrm.1910360308] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A homogeneous static (B0) magnetic field is required for many NMR experiments such as echo planar imaging, localized spectroscopy, and spiral scan imaging. Although semi-automated techniques have been described to improve the B0 field homogeneity, none has been applied to the in vivo heart. The acquisition of cardiac field maps is complicated by motion, blood flow, and chemical shift artifact from epicardial fat. To overcome these problems, an ungated three-dimensional (3D) chemical shift image (CSI) was collected to generate a time and motion-averaged B0 field map. B0 heterogeneity in the heart was minimized by using a previous algorithm that solves for the optimal shim coil currents for an input field map, using up to third-order current-bounded shims (1). The method improved the B0 homogenelty of the heart in all 11 normal volunteers studied. After application of the algorithm to the unshimmed cardiac field maps, the standard deviation of proton frequency decreased by 43%, the magnitude 1H spectral linewidth decreased by 24%, and the peak-peak gradient decreased by 35%. Simulations of the high-order (second- and third-order) shims in B0 field correction of the heart show that high order shims are important, resulting for nearly half of the improvement in homogeneity for several subjects. The T2* of the left ventricular anterior wall before and after field correction was determined at 4.0 Tesis. Finally, results show that cardiac shimming is of benefit in cardiac 31P NMR spectroscopy and cardiac echo planar imaging.
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186
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Wen H, New RR, Muhmut M, Wang JH, Wang YH, Zhang JH, Shao YM, Craig PS. Pharmacology and efficacy of liposome-entrapped albendazole in experimental secondary alveolar echinococcosis and effect of co-administration with cimetidine. Parasitology 1996; 113 ( Pt 2):111-21. [PMID: 8760312 DOI: 10.1017/s003118200006635x] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Encapsulation of the benzimidazole albendazole in multilamellar liposomes results in a preparation in which this normally insoluble anti-hydatid drug is well solublilized in aqueous media. The high entrapment efficiency observed (75-87%) and the stability of the formulation make this a promising delivery vehicle for improved chemotherapy with albendazole. In particular, the high degree of association with phospholipid may give rise to increased oral bioavailability. Oral administration of albendazole in liposomes led to increased concentration and/or altered metabolism of albendazole sulphoxide (ABZSX) in liver and/or plasma in non-infected Wistar rats. Results from experiments using cotton rats (Sigmodon hispidus) infected with metacestodes of Echinococcus multilocularis show that entrapment within liposomes clearly increases the uptake of albendazole via the oral route. This was reflected by increased levels of albendazole and the two major metabolites in plasma, liver and cyst homogenate when a dose of liposomal albendazole (35 mg/kg) was given orally compared to free albendazole at 50 mg/kg. There was a 75-94% reduction in biomass of the metacestode and a significant increase in survival time for the animals treated with liposome entrapped albendazole. A clear difference in distribution of albendazole and its metabolites in the liver and the metacestode tissues in the presence of cimetidine indicated that the latter has a profound effect on the metabolism of albendazole. There appeared to be a synergistic interaction between albendazole and cimetidine, since the metabolism of albendazole was markedly altered in the combined cimetidine/ liposome-albendazole group, and higher therapeutic effect was observed. These findings indicate potential both for improvement of treatment of larval E. multilocularis infection and for reduction of albendazole dose levels.
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187
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Duewell S, Wolff SD, Wen H, Balaban RS, Jezzard P. MR imaging contrast in human brain tissue: assessment and optimization at 4 T. Radiology 1996; 199:780-6. [PMID: 8638005 DOI: 10.1148/radiology.199.3.8638005] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE To evaluate multiple magnetic resonance (MR) imaging sequences for their ability to provide T1 and T2-weighted images at a field strength of 4 T, and to validate previously obtained relaxation time measurements. MATERIALS AND METHODS Different spin-echo, inversion-recovery (IR), gradient-recalled acquisition in the steady state (GRASS), and magnetization transfer contrast-enhanced GRASS sequences were evaluated in a single section, each in at least four volunteers. Also, interleaved echo-planar imaging (IEPI) and interleaved gradient-recalled echo (IGRE) sequences were analyzed and compared with standard sequences. RESULTS Predicted contrast behavior, according to MR relaxation time measurements, was found to agree well with that of the validation experiments. Fair T1 contrast can be achieved on MR images at 4 T, contrary to early predictions. Under other conditions, however, such as partially spin-density-weighted parameters, lower contrast is observed at the high field strength when compared with conventional field strengths. CONCLUSION The longer T1 values at higher field strengths have a substantial effect on image contrast. Depending on the sequence and parameters chosen, good image contrast can be realized at 4 T. IEPI and hybrid IR IGRE sequences are useful in shortening the prolonged examination times owing to the longer T1 values at higher field strengths.
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188
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Li J, He W, Yao J, Wen H. Possibility of observing the changes of cerebrospinal fluid pulse waves as a substitute for volume pressure test. Chin Med J (Engl) 1996; 109:411-3. [PMID: 9208503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
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189
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Wen H, Jaffer FA, Denison TJ, Duewell S, Chesnick AS, Balaban RS. The evaluation of dielectric resonators containing H2O or D2O as RF coils for high-field MR imaging and spectroscopy. JOURNAL OF MAGNETIC RESONANCE. SERIES B 1996; 110:117-23. [PMID: 8819760 PMCID: PMC2889621 DOI: 10.1006/jmrb.1996.0019] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Electromagnetic resonators consisting of low-loss dielectric material and/or metallic boundaries are widely used in microwave technologies. These dielectric resonators usually have high Q factors and well-defined field distributions. Magnetic resonance imaging was shown as a way of visualizing the magnetic field distribution of the resonant modes of these resonators, if the dielectric body contains NMR sensitive nuclei. Dielectric resonators have also been proposed as RF coils for magnetic resonance experiments. The feasibility of this idea in high-field MR is discussed here. Specifically, the dielectric resonances of cylindrical water columns were characterized at 170.7 MHz (4 T 1H Larmor frequency), and evaluated as NMR transmit and receive coils. The dielectric resonance of a cylindrical volume of D2O was used to image a hand at 170.7 MHz. This study demonstrated that MRI is an effective way of visualizing the magnetic field in dielectric structures such as a water cylinder, and can potentially be generalized to solid-state dielectric devices. The possible applications of dielectric resonators other than simple cylindrical volumes in MRI and MR solution spectroscopy at high field strengths are also discussed.
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190
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Wen H, Jaffer FA. An in vivo automated shimming method taking into account shim current constraints. Magn Reson Med 1995; 34:898-904. [PMID: 8598818 PMCID: PMC2896433 DOI: 10.1002/mrm.1910340616] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/1994] [Accepted: 06/30/1995] [Indexed: 01/31/2023]
Abstract
Many in vivo imaging techniques require magnetic field homogeneity in the volume of interest. Shim coils of the second and third order spherical harmonics have been used successfully to compensate for complicated field variations caused by the human anatomy itself. The available currents of these coils are invariably limited. In this note we demonstrate that these limits significantly affect the optimal shim condition. We propose an automated in vivo shimming method for arbitrary volumes of interest using 3-dimensional (3D) field maps. This method is a modification of previous works using least-squares criteria. The main difference is that a constrained optimization is performed in vivo under the current limits of the shim coils, which improved the field homogeneity significantly over simple truncations of the least-squares solutions. This shimming method was used with head scans of five normal volunteers on a 4.0 tesla scanner. A fast double-echo sequence was used to obtain field maps, and a new field uniformity measure was derived for this method. The field mapping sequence was tested against a standard single-echo Dixon sequence used by previous investigators, and the stability of the shimming method was tested by repeated studies on the same subject.
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191
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Liu Y, Zhou Y, Wen H. [Diagnosis and treatment of postmenopausal uterine bleeding by hysteroscopy]. ZHONGHUA FU CHAN KE ZA ZHI 1995; 30:732-4. [PMID: 8728918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
OBJECTIVES To evaluate the value of hysteroscopy in diagnosis and treatment of patients with postmenopausal uterine bleeding. METHODS One hundred and thirty-five patients with postmenopausal bleeding hospitalized in our department from July 1990 to July 1994 were examined by hysteroscopy. The results of 124 cases were compared with pathological findings obtained during uterine curettage. Thirty-nine patients were operated simultaneously under hysteroscopy. RESULTS Under hysteroscopy, atrophic endometrium, endometrial polyps, cervical polyps, endometrial carcinoma, endometrial hyperplasia, submucous myoma were diagnosed in 62 cases (45.9%), 25 cases (18.5%), 13 cases (9.6%), 13 cases (9.6%), 11 cases (8.2%) and 5 cases (3.7%) respectively. The remaining 6 (4.5%) had IUD insertion. These findings were confirmed pathologically in 115 out of 124 cases (92.7%). There were 9 cases misdiagnosed by hysteroscopy. 6 cases had false negative results during previous curettage. Twenty-two cases of endometrial polyps, 13 cases of cervical polyps and 4 cases of pediculated submucous myoma were removed hysteroscopically without any complication. CONCLUSIONS Hysteroscopy is an effective method for identifying the causes of postmenopausal uterine bleeding, which is superior to curettage of uterus. For some selected patients hysteroscopic operations can be performed at the same time.
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192
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Ong KC, Wen H, Chesnick AS, Duewell S, Jaffer FA, Balaban RS. Radiofrequency shielding of surface coils at 4.0 T. J Magn Reson Imaging 1995; 5:773-7. [PMID: 8748501 DOI: 10.1002/jmri.1880050626] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Because radiation loss associated with a radiofrequency (RF) coil increases as roughly the fourth power of the frequency, this loss mechanism may become important in high-field studies above 2.0 T. In this study, the contribution of radiation losses at 4.0 T were determined in a rectangular surface coil using an RF shield to modify the radiation losses. The effect of this shield was determined on coil Q, B1 distribution, and signal to noise as a function of distance between the coil and the shield. Phantoms and human tissue were evaluated to characterize the loss mechanisms. The results demonstrate a large radiation loss in the unshielded surface coil. However, the radiation losses in vivo were not dominant owing to a large inductive loss occurring from dielectric currents in the body at 170 MHz.
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193
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Wen H, Bresson-Hadni S, Vuitton DA, Lenys D, Yang BM, Ding ZX, Craig PS. Analysis of immunoglobulin G subclass in the serum antibody responses of alveolar echinococcosis patients after surgical treatment and chemotherapy as an aid to assessing the outcome. Trans R Soc Trop Med Hyg 1995; 89:692-7. [PMID: 8594699 DOI: 10.1016/0035-9203(95)90449-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Immunoglobulin G (IgG) subclass-specific antibody responses were evaluated for the follow-up of alveolar echinococcosis (AE) patients. Seventy-four sequentially collected sera from 25 Chinese and French AE cases who underwent surgery including hepatectomy, liver transplant and/or chemotherapy were analysed quantitatively and qualitatively during the clinical follow-up period. These AE patients were classified in 4 groups--cured, improved, stabilized, or aggravated. Serum antibody levels of the subclasses IgG1 and IgG4 were significantly higher in the AE patients than in healthy controls. IgG1 and IgG4 isotypes in AE patients were the most sensitive IgG antibody response in an enzyme-linked immunosorbent assay (ELISA) and in binding to antigens of 44kDa, 35kDa, 21kDa and 17.5kDa in an Echinococcus multilocularis protoscolex extract after Western blotting. In AE cases classed as cured or improved, IgG subclass antibody levels tended to decrease earlier than total IgG levels, especially IgG4 antibody levels which became negative within one year after successful treatment. IgG4 antibody levels also decreased in most of the improved cases. Increasing or unchanged levels of IgG4 and IgG1 antibodies were demonstrated in both stabilized and aggravated AE cases using both ELISA and immunoblot assays. Reappearance of specific IgG4 antibodies was a strong indication of recurrence, especially in liver transplant patients. Combined quantitative and qualitative assessment of IgG1 and IgG4 antibodies may be potentially useful for the serological follow-up of human AE.
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Wen H, Craig PS, Ito A, Vuitton DA, Bresson-Hadni S, Allan JC, Rogan MT, Paollilo E, Shambesh M. Immunoblot evaluation of IgG and IgG-subclass antibody responses for immunodiagnosis of human alveolar echinococcosis. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 1995; 89:485-95. [PMID: 7495362 DOI: 10.1080/00034983.1995.11812981] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Antigen binding of total-IgG and IgG-subclass antibodies from patients with alveolar or cystic echinococcosis (AE and CE) was assessed by immunoblotting. Antigen extracts were prepared from Echinococcus multilocularis protoscoleces (EmP) or from homogenized E. multilocularis metacestode tissue (EmCH). Antigens of approximately 44, 35, 21, 17.5 and 16.5 were recognized by total-IgG and IgG1- and IgG4-subclass antibodies in some of 50 human AE sera from China, Japan or France. The 44- and 35-kDa polypeptides, present in both EmP and EmCH extracts, were recognized by total-IgG antibodies in sera from 82% and 66% of the AE patients, respectively. However, over 30% cross-reactivity occurred between these two antigens and sera from CE and Taenia solium cysticercosis patients. The immunoblot specificities of the 27-, 21- and 17.5-kDa antigens in EmP for E. multilocularis infection were 73%, 88% and 93%, respectively. Recognition of the 17.5-kDa antigen in the EmP immunoblot was much higher for the Japanese AE cases (11/13; 85%) than for the French (9/19; 47%) or Chinese (9/18; 50%) AE cases. None of the CE cases from Uruguay or Libya, where human AE has not been reported, was seropositive for the 17.5-kDa antigen. Antibodies from three (7.3%) of the 41 Chinese CE cases recognized the 17.5-kDa antigen. Within the 13 Japanese AE sera, the combined detection by IgG1, IgG4 and total-IgG antibodies of the 27-, 21- and 17.5-kDa antigens in either EmP or EmCH immunoblots was greater than that by each class/subclass alone, increasing the overall sensitivity for AE patients. A combined ELISA/immunoblot approach, including IgG-subclass detection using E. multilocularis protocolex or cyst extracts, could be useful for the differential diagnosis of human alveolar echinococcosis. An algorithm for such an approach is given.
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Duewell SH, Ceckler TL, Ong K, Wen H, Jaffer FA, Chesnick SA, Balaban RS. Musculoskeletal MR imaging at 4 T and at 1.5 T: comparison of relaxation times and image contrast. Radiology 1995; 196:551-5. [PMID: 7617876 DOI: 10.1148/radiology.196.2.7617876] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
PURPOSE To evaluate the relaxation time-based contrast between the main tissues of the musculoskeletal system as measured in the human knee with magnetic resonance imaging at 4 T and 1.5 T. MATERIALS AND METHODS Five volunteers underwent 4-T and 1.5-T imaging. Inversion-recovery series were used to measure T1 values, and T2 values were measured with a spin-echo sequence. RESULTS T1 values increased in all tissues with 4-T imaging. Values increased in muscle from 1 to 1.8 seconds, in fat from 0.3 to 0.4 seconds, and in cartilage from 0.8 to 1.5 seconds. T2 values were 10%-20% shorter in all tissues at 4 T. CONCLUSION Advantages of 4-T imaging compared with 1.5-T imaging include a higher signal-to-noise ratio and an improved signal difference-to-noise ratio. However, any improvement in signal-to-noise ratio at high field strengths can partially be reduced by the increase in the T1 value. The slightly shorter T2 values at 4 T do not affect image contrast.
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Berlin CI, Hood LJ, Hurley AE, Wen H, Kemp DT. Binaural noise suppresses linear click-evoked otoacoustic emissions more than ipsilateral or contralateral noise. Hear Res 1995; 87:96-103. [PMID: 8567448 DOI: 10.1016/0378-5955(95)00082-f] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We studied the efferent suppression of click-evoked otoacoustic emissions with 65 dB SPL of white noise presented to left, right, or sometimes both, ears for 408 ms. Each burst of noise preceded a series of four unipolar 80 microseconds 65 dB peak Sound Pressure clicks, presented to the left ear only. The first click of the four-click group followed the end of the noise by either 1, 2, 5, 10, 20, 50, 100 or 200 ms; each subsequent click was offset by 20 additional ms via an ILO88 system with special programming modifications. Conditions were alternated so that a 'without noise' condition preceded a 'with noise' condition for three repetitions of 600 clicks per trial. Seven subjects with normal hearing participated in the study, and three of the seven participated in a test-retest reliability study. Results showed the greatest suppression followed binaural stimulation ending within one to five ms of the first click in the pulse train. Somewhat less suppression was seen following ipsilateral stimulation. The least amount of suppression was seen following contralateral stimulation, suggesting that previous research using contralateral stimulation may underestimate efferent effects. We saw no effects when the end of the noise was 100 ms or more away from the beginning of the click train.
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197
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Shambesh MK, Craig PS, Gusbi AM, Echtuish EF, Wen H. Immunoblot evaluation of the 100 and 130 kDa antigens in camel hydatid cyst fluid for the serodiagnosis of human cystic echinococcosis in Libya. Trans R Soc Trop Med Hyg 1995; 89:276-9. [PMID: 7660432 DOI: 10.1016/0035-9203(95)90538-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Two high molecular weight antigens with molecular masses approximately 100 kDa and 130 kDa were identified by immunoblotting camel hydatid cyst fluid, with 94% sensitivity in sera from surgically confirmed Libyan cystic echinococcosis cases. 40% of sera from surgically confirmed alveolar echinococcosis cases cross-reacted with the 100 and 130 kDa antigens, as did 5.3% of sera from human Taenia solium cysticercosis patients. No cross-reaction occurred with sera from human schistosomiasis mansoni or onchocerciasis patients. In addition, all sera from patients with non-hydatid space-occupying lesions (i.e. simple liver cysts, kidney cysts, lung tuberculosis, pulmonary carcinoma, pulmonary empyema, and lung abscess) were seronegative against the same antigens, as were control serum samples from healthy individuals. The 100 and 130 kDa antigens were strongly recognized by sera from cystic echinococcosis patients when camel or horse hydatid cyst fluid was used in immunoblotting but were only weakly recognized if sheep or human hydatid cyst fluid was used. Camel hydatid cyst fluid could be an important source of diagnostic antigens for human cystic echinococcosis in the Middle East endemic region.
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198
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Chen RA, Wen H. [Clinical study on treatment of male infertility with shengjing pill]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 1995; 15:205-8. [PMID: 7647540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
202 cases of male infertility were treated with Shengjing Pill. After treatment, quantity and quality of sperm were significantly improved (P < 0.001), levels of follicle stimulating hormone (FSH), luteinizing hormone (LH) and testosterone (T) were enhanced to normal in 96 patients (P < 0.001), levels of anti-sperm-antibody was reduced to normal in 45 cases (P < 0.001), of 148 follow-ups. Their 116 spouses became pregnant and have borne 108 well-developed babies.
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199
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Wen H, Craig PS. Immunoglobulin G subclass responses in human cystic and alveolar echinococcosis. Am J Trop Med Hyg 1994; 51:741-8. [PMID: 7810806 DOI: 10.4269/ajtmh.1994.51.741] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Immunoglobulin G (IgG) subclass-specific antibody responses were investigated in both human cystic echinococcosis (CE) and alveolar echinococcosis (AE) by enzyme-linked immunosorbent assay (ELISA) and Western blotting. Sera were tested from 81 CE and 50 AE surgically confirmed cases using partially purified hydatid cyst fluid antigen B (EgB), and crude hydatid cyst fluid (EgCF) from Echinococcus granulosus and a protoscolex extract (EmP) prepared from E. multilocularis metacestodes. Eighty-nine percent of CE patients and 94% of AE patients were seropositive for total IgG antibodies. The dominant IgG antibody isotype in both CE and AE was IgG4, for which 73% of CE and 84% of AE cases were seropositive in the ELISA. Anti-Echinococcus IgG1 antibodies were detected in 58% of CE and 84% of AE patients. Sensitivity for IgG2 and IgG3 was significantly lower for both CE and AE patients. The IgG4 antibodies in CE patients predominantly recognized the E. granulosus antigen B subunits, i.e., at 20, 16 and 12 kD, while IgG1 antibodies primarily bound to the 38-kD subunit of antigen 5 from E. granulosus hydatid fluid. The possible functional significance of an IgG4 response and the potential use of combined assessment of total IgG, IgG1, and IgG4 antibodies in serologic diagnosis and follow-up for human echinococcosis are discussed.
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Kalyanasundari M, Panchanatheswaran K, Parthasarathi V, Robinson WT, Wen H. Benzoylmethylenetriphenylphosphorane, C26H21OP. Acta Crystallogr C 1994. [DOI: 10.1107/s0108270194001137] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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