451
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Zhou G. [The C/D ratio in normal newborns]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 1993; 29:105-7. [PMID: 8404351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The optic disc and the C/D ratio were examined in 122 newborns to find that the features of the C/D ratio were positive skewness distribution with leptokurtosis, a wide variability, lesser values of the mean, the median and the 95% upper limit, and non-correlation with the length of pregnancy and the height and weight of the baby at birth. The authors suggested that C/D > 0.3 or a binocular difference of > 0.2 could be regarded as one of the criteria of newborn glaucoma. It was also found that more greyish glial tissue was on the optic disc. The scope of the physiological optic cup was determined by the naked status of the central retinal vessels in the pale area.
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452
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Reddy HK, Campbell SE, Janicki JS, Zhou G, Weber KT. Coronary microvascular fluid flux and permeability: influence of angiotensin II, aldosterone, and acute arterial hypertension. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 1993; 121:510-21. [PMID: 8445300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Vascular permeability of the coronary and mesenteric circulation is increased in association with the arterial hypertension that accompanies either endogenous activation of the renin-angiotensin-aldosterone system (RAAS) or exogenous administration of angiotensin II (AII). Whether this occurs as a result of increased intravascular pressure or of elevations in plasma concentrations of AII or aldosterone (ALDO) (or both) is unclear. This acute study of filtration-independent coronary fluid exchange and macromolecular permeability was undertaken to address these issues in open-chest, anesthetized dogs. The influence of arterial hypertension, with or without associated elevations in plasma AII or ALDO (or both), on coronary permeability was examined by monitoring the response in cardiac lymph flow, protein concentration, and capillary and intramural coronary artery structure. Experimental groups received a 90-minute intravenous infusion of either AII (n = 8), methoxamine (MX; n = 7), or ALDO plus MX (n = 5) in equipotent doses that raised arterial pressure to comparable levels. When we compared these animals with normotensive, instrumented controls (n = 5), we found that (1) lymph flow was a function of arterial and microvascular pressures in each group; (2) increased protein permeability, myocardial edema, extravasated red cells, and infused colloidal carbon were found in both ventricles with AII, together with endothelial discontinuities and enhanced abluminal capillary endothelial vesicle formation, when plasma ALDO had risen significantly in response to AII; and (3) macromolecular permeability was no different from that in controls after MX or ALDO plus MX. Based on this short-term study of acute arterial hypertension, we would conclude that acute elevations in microvascular pressure increase fluid flux, whereas increased circulating effector hormones of the RAAS, not plasma ALDO or hypertension alone, alter coronary microvascular structure and permeability to macromolecules Responsible mechanisms remain to be defined.
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453
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Zhou G, Anderson DZ. Photorefractive delay line for the visualization and processing of time-dependent signals. OPTICS LETTERS 1993; 18:167-169. [PMID: 19802073 DOI: 10.1364/ol.18.000167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We present an optical time-delay line based on photorefractive beam coupling in a rotating crystal. The delay line can be tapped continuously or at selected positions.We demonstrate a 64-channel device with a BaTiO(3) crystal rotating at 1.5 rpm, which gives approximately a 167-Hz bandwidth and 0.5 s of time delay for each channel.
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454
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Weber KT, Brilla CG, Campbell SE, Guarda E, Zhou G, Sriram K. Myocardial fibrosis: role of angiotensin II and aldosterone. Basic Res Cardiol 1993; 88 Suppl 1:107-24. [PMID: 8395170 DOI: 10.1007/978-3-642-72497-8_8] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In this report we review the replacement (i.e., scarring) and reactive (i.e., perivascular and interstitial fibrosis) fibrous tissue responses found in the myocardium in response to effector hormones of the renin-angiotensin-aldosterone system. Experimental data are presented to indicate: a) endogenous or exogenous elevations in plasma angiotensin II are associated with acute cardiac myocyte necrosis and subsequent microscopic scarring; b) chronic elevations in plasma aldosterone (ALDO), relative to Na+ intake, are associated with a perivascular and interstitial fibrosis of the coronary and systemic circulations and are also seen in response to chronic administration of the mineralocorticoid hormone deoxycorticosterone (DOC); and c) chronic mineralocorticoid excess, due to ALDO or DOC, is associated with enhanced urinary K+ excretion, cardiac myocyte necrosis and scarring. Pharmacologic agents which interfere with these effector hormones (e.g., ACE inhibition and ALDO receptor antagonism) protect the myocardium against this pathologic structural remodeling created by the reactive and replacement (reparative) fibrosis. Evidence is also presented to indicate that chronic ACE inhibition is associated with a regression in reactive myocardial fibrosis. Based on these experimental findings we would suggest that clinical trials are indicated to address the prevention and regression of myocardial fibrosis--an important determinant of pathologic structural remodeling and abnormal myocardial stiffness.
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455
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Zhou G, Xu X, Zhang CT. A weighting method for predicting protein structural class from amino acid composition. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 210:747-9. [PMID: 1483458 DOI: 10.1111/j.1432-1033.1992.tb17476.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A protein is generally classified into one of the following four structural classes: all alpha, all beta, alpha+beta and alpha/beta. In this paper, based on the weighting to the 20 constituent amino acids, a new method is proposed for predicting the structural class of a protein according to its amino acid composition. The 20 weighting parameters, which reflect the different properties of the 20 constituent amino acids, have been obtained from a training set of proteins through the linear-programming approach. The rate of correct prediction for a training set of proteins by means of the new method was 100%, whereas the highest rate of previous methods was 82.8%. Furthermore, the results showed that the more numerous training proteins, the more effective the new method.
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456
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Zhou G, Xiao M, Zhou W. [Glaucomatous hemodynamic changes in central retinal artery and ocular artery]. YAN KE XUE BAO = EYE SCIENCE 1992; 8:156-9. [PMID: 1306494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The hemodynamics of ocular artery (OA) and central retinal artery (CRA) in 100 eyes of 50 normal subjects and 61 eyes of 39 patients with glaucoma were studied with colour doppler image technique. The results showed the hemodynamic characteristics about normal and glaucomatous eyes and that the ischemic change of CRA was one of the high risk factors in glaucomatous visual functional damages. We propose a new classification of glaucomatous hemodynamics and the clinical application of hemodynamic parameters in glaucoma diagnosis. We also, for the first time, make use of hydrodynamic pressure to calculate the retinal perfusion pressure, which explain the phenomena of intraocular pressure increasing with blood flow decreasing and the effect of hyperviscosity as well as cardiovascular disease on glaucoma. A new approach to the research of glaucoma is presented.
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457
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Yu S, Wang Y, Li S, Zhou G, Yu J. [Comparison of constituents in Pueraria thomsonii Benth before and after processing]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1992; 17:534-6, 575. [PMID: 1292491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Determinations of aqueous extract, alcoholic extract, flavonoids and puerarin as well as ten inorganic elements in Pueraria thomsonii have been made before and after processing. The results showed that the above mentioned ingredients all varied in amount.
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458
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Zhou G, Broyles SS, Dixon JE, Zalkin H. Avian glutamine phosphoribosylpyrophosphate amidotransferase propeptide processing and activity are dependent upon essential cysteine residues. J Biol Chem 1992; 267:7936-42. [PMID: 1560022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Avian glutamine phosphoribosylpyrophosphate amidotransferase contains an NH2-terminal propetide-like sequence. NH2-terminal sequence analysis of immunoaffinity purified enzyme from chicken liver indicates that the propeptide is processed and the mature enzyme starts with Cys. Propeptide processing was investigated by site-directed mutagenesis using a system for expression in HeLa cells. Glutamine-dependent activity and processing were abolished by replacement of the conserved cysteine at position 1, whereas NH3-dependent activity was retained. Cys1 is thus inferred to have a role in glutamine-dependent activity and in propeptide processing. Inactive, insoluble enzymes in which the propeptide was not processed were obtained as a result of replacements of cysteines 415 and 488. Cysteine residues at positions 415 and 488 are inferred to be ligands to an Fe-S cluster on the basis of sequence similarity to the enzyme from Bacillus subtilis. Mutation of Cys269 and Cys295 led to loss of enzyme activity and propeptide processing, although solubility was unchanged. The results suggest that incorporation of an Fe-S cluster is needed for native structure, resultant propeptide processing, and glutamine-dependent activity.
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459
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Zhou G, Bintz L, Anderson DZ. Fiber-optic acoustic Fourier transducer for audio sound processing. APPLIED OPTICS 1992; 31:1740-1744. [PMID: 20720812 DOI: 10.1364/ao.31.001740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We demonstrate a fiber-optic acoustic transducer operating in the audio-frequency regime. The device is made of an array of 120 multimode optical fibers and a photorefractive novelty filter. Each fiber in the array acts as a cantilevered mechanical resonator. The resonant frequencies of the fibers logarithmically sample the acoustic spectrum from approximately 100 Hz to 5 kHz. Laser light is injected into all fibers simultaneously and is reflected from the end of each fiber. An optical novelty filter extracts the acoustic information from the reflected light. The output of the novelty filter is essentially a Fourier transform of the acoustic signal. The background intensity in the transducer output corresponds to a driving amplitude of approximately 50 A. We describe holographic storage of complex sound patterns that use a LiNbO(3) crystal and an acoustic transducer.
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460
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Zhou G, Broyles S, Dixon J, Zalkin H. Avian glutamine phosphoribosylpyrophosphate amidotransferase propeptide processing and activity are dependent upon essential cysteine residues. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)42602-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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461
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Qiao Q, Ling Y, Zhou G, Song R. Breast volume measurement in 125 young Chinese women. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1992; 7:44-8. [PMID: 1421362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The authors carried out research on breast volume and body surface anatomy of 125 unmarried young women. As a result, an average breast volume for young Chinese women was obtained (325.36 +/- 12.66 ml), and a table together with several linear equations for calculating breast volume were derived. These will provide plastic surgeons with useful tools for designing mammaplasty procedures.
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462
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Fang Z, Yang Y, Zhou G. [Isolation and identification of chemical constituents from Hedyotis chrysotricha (Palib.) Merr]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1992; 17:98-100, 127. [PMID: 1418534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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463
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Chen L, Hu YY, Zhou G, Wang DS, Goings GE, Page E. [The study on ultrastructure of gap junction of rat atrial myocytes in primary culture]. SHI YAN SHENG WU XUE BAO 1991; 24:343-51. [PMID: 1796718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We have studied the ultrastructure of gap junction of rat atrial myocytes of primary culture in situ embedded by ultramicrotomy. We observed a kind of gap junction-associated vesicles (GJAV), a kind of cluster of particles which are surrounded by plasma membrane, and a concatenate GJAV complexes (CGJAVC) in some big clusters. We found that both of GJAV and CGJAVC are very near the plasma membrane at the intercellular space, and at the same time they are usually adjacent the assembled GJ. So we infered that they are the pre-body or midproduct of the assembled GJ probably. This article analysed these observes and probed into the process about how to assemble the gap junction.
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464
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Yu B, Zhou G, Wang B, Ben Y, Yan H, Shao Y, Wang B. A clinical and laboratory study of ciclopirox olamine (8% Batrafen) in the treatment of onychomycosis. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1991; 6:166-8. [PMID: 1838936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Ciclopirox olamine, a new synthetic substituted pyridone derivative, is an antimycotic agent with activity against a broad spectrum of pathogenic and nonpathogenic fungi. The clinical efficacy and safety of 8% ciclopirox olamine nail liquor were evaluated in 100 cases with finger (or great toe) onychomycosis. After 16 weeks and 24 weeks of treatment for finger and great toe onychomycosis, respectively, the overall therapeutic results were excellent in 36 cases, good in 17, fair in 24, and poor in 23. The period of treatment was extended in 31 cases; among them, 10 cases showed further improvement. As for in vitro inhibitory activity, the MIC of ciclopirox olamine against T. rubrum and C. albicans was 1 to 4 mg/L and 1 to 16 mg/L, respectively. This study indicates that 8% ciclopirox olamine nail liquor, with its satisfactory efficacy and lack of side effects, is a good remedy for onychomycosis.
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465
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Yao Q, Zhou G, Zhu Y, Pan Y, Hu J, Xue H, Zhang Q. [Screening studies on anti-inflammatory function of traditional Chinese herb Gardenia jasminoides Ellis and its possibility in treating soft tissue injuries in animals]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1991; 16:489-93, 513. [PMID: 1804189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This paper reports the study of six fractions and one chemical constituent isolated from the traditional Chinese herb Gardenia jasminoides. The results showed that two fractions (G5.G6,), alcohol extract (G1) and genipoiside(A) had obvious anti-inflammatory effects and were comparatively effective in treating soft tissue injuries in animals.
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466
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Huang BX, Lin SQ, Chen SY, Zhou G, Yin F, Lou ZP, Bi MM. Hair chromium levels in patients with vascular diseases. Biol Trace Elem Res 1991; 29:133-7. [PMID: 1713469 DOI: 10.1007/bf03032690] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The chromium levels in the hair of patients with hyperlipemia and coronary heart disease were found to be similar to those of healthy controls (p greater than 0.2). In patients with cerebral hemorrhage and cerebral thrombosis, significantly higher hair chromium values were observed than in healthy subjects (p less than 0.001). The possible significance of these findings is discussed.
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467
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Zhou G, Qiao Q, Chen GY, Ling YC, Swift R. Clinical experience and surgical anatomy of 32 free anterolateral thigh flap transplantations. BRITISH JOURNAL OF PLASTIC SURGERY 1991; 44:91-6. [PMID: 2018912 DOI: 10.1016/0007-1226(91)90038-l] [Citation(s) in RCA: 117] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The anterolateral thigh flap, first described by Song, is one of the septocutaneous flaps in the thigh. Since November 1985 we have transferred 32 anterolateral thigh flaps successfully without any loss. Six of these flaps were performed in Australia. The vascular pedicles are divided into three types: fasciocutaneous perforator (37.5%-12/32), vertical musculocutaneous perforator (56.2%-18/32) and horizontal musculocutaneous perforator (6.6%-2/32). This paper presents the surgical anatomy of the flap and clinical experience.
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468
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Zhou G. [Experiences in free anterio-lateral femoral skin flap grafting. Report of 32 cases]. ZHONGHUA ZHENG XING SHAO SHANG WAI KE ZA ZHI = ZHONGHUA ZHENG XING SHAO SHANG WAIKF [I.E. WAIKE] ZAZHI = CHINESE JOURNAL OF PLASTIC SURGERY AND BURNS 1990; 6:255-7. [PMID: 2282583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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469
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Zhou G, Jia M. [Pharmacognostical studies on flos Houpo produced in Yunnan Province]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1990; 15:583-7, 624, 638. [PMID: 2268394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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470
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Zhou G. [1-stage reconstruction of microtia associated with hemifacial soft tissue aplasia]. ZHONGHUA ZHENG XING SHAO SHANG WAI KE ZA ZHI = ZHONGHUA ZHENG XING SHAO SHANG WAIKF [I.E. WAIKE] ZAZHI = CHINESE JOURNAL OF PLASTIC SURGERY AND BURNS 1990; 6:20-1, 74. [PMID: 2357629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Four cases of microtia association with hemifacial aplasia were repaired by one-stage reconstruction. The operations included external ear reconstruction and correction of facial deformity with free vascularized dermis fat flaps. All were successful, the results were satisfied. The method and the device of the operation are described in detail. The advantages of the technique are discussed.
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471
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Zhou G, Yang L. [Relation of the changes in hemorheologic indices and the site and size of cerebral infarction]. ZHONGHUA SHEN JING JING SHEN KE ZA ZHI = CHINESE JOURNAL OF NEUROLOGY AND PSYCHIATRY 1990; 23:31-4, 63. [PMID: 2347278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
According to the CT findings, 83 cases of cerebral infarction were divided into two groups. One group consisted of cases with occlusion of the cerebral arterial main trunks and the other of those with occlusion of the penetrating arteries. The HCT and the whole blood viscosity were higher in the former group, whereas the rate of platelet aggregation was higher in the latter group. These results suggested that the physiopathology involved in the formation of the large cerebral infarction in the cerebral cortex and subcortex was different from that of the small infarction in the deep cerebral structures. Besides, it was found that the blood viscosity has positive relationship with the size of the cerebral infarction in the former group. It was presumed that the HCT and the blood viscosity should be reduced immediately for treating the larger cerebral infarction, but to lower the rate of platelet aggregation for treating the small infarction in the deep cerebral structures would be of benefit.
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472
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Zhou G, Ling YC, Qiao Q. Experience using microvascular anastomotic rings for the transplantation of 20 free flaps. Plast Reconstr Surg 1989; 84:822-6. [PMID: 2813594 DOI: 10.1097/00006534-198911000-00020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A new microvascular anastomosis technique was employed with success in 1985-1986 with the result of 18 free-flap survivals and 2 failures. The rate of success in microvascular anastomoses was 90.5 percent (38 of 42). The advantages of this technique are its simplicity, convenience, and safety, and it may shorten the duration of the operation. Our experience in using vascular anastomotic rings is presented.
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473
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Zhu XZ, Zhou G. [Neuropeptide antagonists]. SHENG LI KE XUE JIN ZHAN [PROGRESS IN PHYSIOLOGY] 1989; 20:318-22. [PMID: 2561223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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474
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Koh J, Goudy A, Huang P, Zhou G. A comparison of the hydriding and dehydriding kinetics of LaNI5 hydride. ACTA ACUST UNITED AC 1989. [DOI: 10.1016/0022-5088(89)90536-5] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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475
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Connelly PR, Gill SJ, Miller KI, Zhou G, van Holde KE. Identical linkage and cooperativity of oxygen and carbon monoxide binding to Octopus dofleini hemocyanin. Biochemistry 1989; 28:1835-43. [PMID: 2719937 DOI: 10.1021/bi00430a061] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Employment of high-precision thin-layer methods has enabled detailed functional characterization of oxygen and carbon monoxide binding for (1) the fully assembled form with 70 binding sites and (2) the isolated chains with 7 binding sites of Octopus dofleini hemocyanin. The striking difference in the cooperativities of the two ligands for the assembled decamer is revealed through an examination of the binding capacities and the partition coefficient, determined as functions of the activities of both ligands. A global analysis of the data sets supported a two-state allosteric model assuming an allosteric unit of 7. Higher level allosteric interactions were not indicated. This contrasts to results obtained for arthropod hemocyanins. Oxygen and carbon monoxide experiments performed on the isolated subunit chain confirmed the presence of functional heterogeneity reported previously [Miller, K. (1985) Biochemistry 24, 4582-4586]. The analysis shows two types of binding sites in the ratio of 4:3.
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