76
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Lai X, Lin Z, Ward ES, Ober RJ. Noise suppression of point spread functions and its influence on deconvolution of three-dimensional fluorescence microscopy image sets. J Microsc 2005; 217:93-108. [PMID: 15655067 DOI: 10.1111/j.0022-2720.2005.01440.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The point spread function (PSF) is of central importance in the image restoration of three-dimensional image sets acquired by an epifluorescent microscope. Even though it is well known that an experimental PSF is typically more accurate than a theoretical one, the noise content of the experimental PSF is often an obstacle to its use in deconvolution algorithms. In this paper we apply a recently introduced noise suppression method to achieve an effective noise reduction in experimental PSFs. We show with both simulated and experimental three-dimensional image sets that a PSF that is smoothed with this method leads to a significant improvement in the performance of deconvolution algorithms, such as the regularized least-squares algorithm and the accelerated Richardson-Lucy algorithm.
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77
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Luo K, Lai X, Yi CW, Davis KA, Gath KK, Goodman DW. The Growth of Silver on an Ordered Alumina Surface. J Phys Chem B 2005; 109:4064-8. [PMID: 16851464 DOI: 10.1021/jp045948k] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The growth of Ag on an ordered Al2O3 surface was studied by low energy ion scattering spectroscopy (LEIS), scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and temperature programmed desorption (TPD). Three-dimensional (3D) growth of Ag clusters was observed with STM and LEIS, with the cluster size increasing with Ag coverage. The XPS core level binding energies and the Auger parameters indicate a weak interaction between the Ag clusters and the Al2O3 support. Final state effects are determined to be the primary contribution to the Ag core level binding energy shift. Nonzero order kinetics was observed for Ag desorption in TPD with the Ag sublimation energy decreasing with decreasing cluster size.
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78
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De Anda JC, Wang XZ, Lai X, Roberts KJ, Jennings KH, Wilkinson MJ, Watson D, Roberts D. Real-time product morphology monitoring in crystallization using imaging technique. AIChE J 2005. [DOI: 10.1002/aic.10410] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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79
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Lai X, Roberts KJ, Avanci LH, Cardoso LP, Sasaki JM. Habit modification of nearly perfect single crystals of potassium dihydrogen phosphate (KDP) by trivalent manganese ions studied using synchrotron radiation X-ray multiple diffraction in Renninger scanning mode. J Appl Crystallogr 2003. [DOI: 10.1107/s0021889803014766] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The X-ray multiple diffraction technique using synchrotron radiation is applied in the preliminary study of the habit modification of KDP samples as induced by incorporation of the trivalent transition metal cation Mn3+. High-resolution Renninger scans of pure and doped KDP were carried out using 400 as the primary reflection, echoing the fact that these impurity species were segregated in the {100} growth sector. The analysis of the Renninger scans of the doped KDP crystals is consistent with the presence of the impurity species chemically bound within the KDP crystal structure, as confirmed through the suppression of the huge observed peak asymmetry, characteristic of perfect crystals. In addition, an extra Renninger-scan peak measured for the doped material is indicative of the impurity atoms occupying interstitial crystallographic sites in the lattice, a result consistent with X-ray standing-wave measurements. Renninger-scan reflection curve widths and lattice parameter measurements reveal the decrease in crystalline perfection (increased mosaic spread, η) and lattice contraction ofca0.4% in theaandclattice directions at the surface plane for the Mn3+-doped KDP samples in comparison with the undoped crystals.
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80
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Lai X, Shen Y, Zhou D, Sehgal P, Shen L, Simon M, Qiu L, Letvin NL, Chen ZW. Immune biology of macaque lymphocyte populations during mycobacterial infection. Clin Exp Immunol 2003; 133:182-92. [PMID: 12869023 PMCID: PMC1808757 DOI: 10.1046/j.1365-2249.2003.02209.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Immune responses of lymphocyte populations during early phases of mycobacterial infection and reinfection have not been well characterized in humans. A non-human primate model of Mycobacterium bovis bacille Calmette-Guerin (BCG) infection was employed to characterize optimally the immune responses of mycobacteria-specific T cells. Primary BCG infection induced biphasic immune responses, characterized by initial lymphocytopenia and subsequent expansion of CD4+, CD8+ and gammadelta T cell populations in the blood, lymph nodes and the pulmonary compartment. The potency of detectable T cell immune responses appears to be influenced by the timing and route of infection as well as challenge doses of BCG organisms. Systemic BCG infection introduced by intravenous challenge induced a dose-dependent expansion of circulating CD4+, CD8+ and gammadelta T cells whereas, in the pulmonary compartment, the systemic infection resulted in a predominant increase in numbers of gammadelta T cells. In contrast, pulmonary exposure to BCG through the bronchial route induced detectable expansions of CD4+, CD8+ and gammadelta T cell populations in only the lung but not in the blood. A rapid recall expansion of these T cell populations was seen in the macaques reinfected intravenously and bronchially with BCG. The expanded alphabeta and gammadelta T cell populations exhibited their antigen specificity for mycobacterial peptides and non-peptide phospholigands, respectively. Finally, the major expansion of T cells was associated with a resolution of active BCG infection and reinfection. The patterns and kinetics of CD4+, CD8+ and gammadelta T cell immune responses during BCG infection might contribute to characterizing immune protection against tuberculosis and testing new tuberculosis vaccines in primates.
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81
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Wang Q, Zhang PZ, Freymueller JT, Bilham R, Larson KM, Lai X, You X, Niu Z, Wu J, Li Y, Liu J, Yang Z, Chen Q. Present-day crustal deformation in China constrained by global positioning system measurements. Science 2001; 294:574-7. [PMID: 11641493 DOI: 10.1126/science.1063647] [Citation(s) in RCA: 845] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Global Positioning System (GPS) measurements in China indicate that crustal shortening accommodates most of India's penetration into Eurasia. Deformation within the Tibetan Plateau and its margins, the Himalaya, the Altyn Tagh, and the Qilian Shan, absorbs more than 90% of the relative motion between the Indian and Eurasian plates. Internal shortening of the Tibetan plateau itself accounts for more than one-third of the total convergence. However, the Tibetan plateau south of the Kunlun and Ganzi-Mani faults is moving eastward relative to both India and Eurasia. This movement is accommodated through rotation of material around the eastern Syntaxis. The North China and South China blocks, east of the Tibetan Plateau, move coherently east-southeastward at rates of 2 to 8 millimeters per year and 6 to 11 millimeters per year, respectively, with respect to the stable Eurasia.
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82
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Lai X, Li Y, Fan Z, Zhang J, Liu B. An analysis of therapeutic effect of drug acupoint application in 209 cases of allergic asthma. J TRADIT CHIN MED 2001; 21:122-6. [PMID: 11498901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Both therapies of traditional crude herb moxibustion and drug acupoint application were used in 209 cases of allergic asthma to compare their long-term and short-term therapeutic effects and to analyze the relationship between clinic therapeutic effects of both therapies and differential types of the disease. The results showed that the short-term total effective rate in the group of drug acupoint application was higher than that in the group of traditional crude herb moxibustion, the therapeutic effects of drug acupoint application being closely related to differential types. Analysis also shows the best short-term therapeutic effect was in the type of heat in the lung while the poorest effect in the type of deficiency of the kidney-yang.
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83
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Chen ZW, Li Y, Zeng X, Kuroda MJ, Schmitz JE, Shen Y, Lai X, Shen L, Letvin NL. The TCR repertoire of an immunodominant CD8+ T lymphocyte population. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:4525-33. [PMID: 11254709 DOI: 10.4049/jimmunol.166.7.4525] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The TCR repertoire of an epitope-specific CD8(+) T cell population remains poorly characterized. To determine the breadth of the TCR repertoire of a CD8(+) T cell population that recognizes a dominant epitope of the AIDS virus, the CD8(+) T cells recognizing the tetrameric Mamu-A*01/p11C(,CM) complex were isolated from simian immunodeficiency virus (SIV)-infected Mamu-A*01(+) rhesus monkeys. This CD8(+) T cell population exhibited selected usage of TCR V beta families and complementarity-determining region 3 (CDR3) segments. Although the epitope-specific CD8(+) T cell response was clearly polyclonal, a dominance of selected V beta(+) cell subpopulations and clones was seen in the TCR repertoire. Interestingly, some of the selected V beta(+) cell subpopulations and clones maintained their dominance in the TCR repertoire over time after infection with SIV of macaques. Other V beta(+) cell subpopulations declined over time in their relative representation and were replaced by newly evolving clones that became dominant. The present study provides molecular evidence indicating that the TCR repertoire shaped by a single viral epitope is dominated at any point in time by selected V beta(+) cell subpopulations and clones and suggests that dominant V beta(+) cell subpopulations and clones can either be stable or evolve during a chronic infection.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- CD8-Positive T-Lymphocytes/virology
- Clone Cells
- Epitopes, T-Lymphocyte/metabolism
- Gene Products, gag/immunology
- Gene Products, gag/metabolism
- Gene Rearrangement, beta-Chain T-Cell Antigen Receptor
- Histocompatibility Antigens Class I/metabolism
- Immunodominant Epitopes/metabolism
- Macaca mulatta
- Molecular Sequence Data
- Protein Binding/genetics
- Protein Binding/immunology
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/isolation & purification
- Simian Acquired Immunodeficiency Syndrome/immunology
- Simian Immunodeficiency Virus/genetics
- Simian Immunodeficiency Virus/immunology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- T-Lymphocyte Subsets/virology
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84
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Lai X, Chen J, Liu Z, Zhou H. [Primary discussion on the imported materia medica]. ZHONG YAO CAI = ZHONGYAOCAI = JOURNAL OF CHINESE MEDICINAL MATERIALS 2001; 24:136-43. [PMID: 11402733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
The features, with respect to medical use, dosage form, manufacture technology and quality, of licensed imported materia medica and botanical preparation in market were discussed in this paper. The international market competition of Chinese Materia Medica was analyzed, and the countermeasure to resist the imported materia medica was also included.
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85
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Lai X, Chusuei C, Luo K, Guo Q, Goodman D. Imaging ultrathin Al2O3 films with scanning tunneling microscopy. Chem Phys Lett 2000. [DOI: 10.1016/s0009-2614(00)01099-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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86
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Wilson SR, Burns PN, Muradali D, Wilson JA, Lai X. Harmonic hepatic US with microbubble contrast agent: initial experience showing improved characterization of hemangioma, hepatocellular carcinoma, and metastasis. Radiology 2000; 215:153-61. [PMID: 10751481 DOI: 10.1148/radiology.215.1.r00ap08153] [Citation(s) in RCA: 212] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE To characterize blood flow in focal hepatic lesions with harmonic ultrasonographic (US) imaging and a microbubble contrast agent. MATERIALS AND METHODS Thirty patients with known hepatic masses were examined after injection of a perfluorocarbon microbubble agent. Tumor vascularity was assessed with continuous, harmonic gray-scale imaging with a low mechanical index (MI). Tumor vascular volume was assessed with brief, high-MI insonation called interval-delay imaging, which caused microbubble destruction. As the total contrast agent volume in the liver reflects the total vascular volume, quantitation of lesion enhancement relative to normal hepatic enhancement helped determine the vascular volume of the tumor relative to that of normal parenchyma. RESULTS Low-MI continuous harmonic imaging showed lesional vessels in hepatocellular carcinomas, minimal or no vessels in hemangiomas, and variable vascularization in metastases. High-MI interval-delay imaging showed greater enhancement in hepatocellular carcinomas than in normal liver (P <.02) and showed less enhancement in hemangiomas than in normal liver (P <.02). Enhancement in metastases was greater in the margins than in the center; as a result, the lesions appeared smaller (P <.03) and less well defined on the interval-delay images. CONCLUSION Contrast-enhanced harmonic imaging appears superior to conventional Doppler US for hepatic mass characterization. Low-MI continuous and high-MI interval-delay imaging can help assess tumor vascular pattern and microvascular volume.
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87
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Zhu B, Shen X, Li C, Lai X, Li Y, Shi K, Feng H, Wang R. [A molecular cytogenetic study on chromosome anomalies of chronic myeloid leukemia]. ZHONGHUA YI XUE YI CHUAN XUE ZA ZHI = ZHONGHUA YIXUE YICHUANXUE ZAZHI = CHINESE JOURNAL OF MEDICAL GENETICS 2000; 17:116-8. [PMID: 10751535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
OBJECTIVE To study the bcr/abl fusion gene in chronic myeloid leukemia (CML) cases with Philadelphia chromosome(Ph) negative, and variant Ph translocations and other chromosome anomalies. METHODS The status of bcr/abl fusion gene in 8 kinds of chromosome anomalies was tested with dual-color fluorescence in situ hybridization (D-FISH) technique. RESULTS The positive hybridization was demonstrated in 3 cases of variant Ph CML and other 7 cases of standard Ph, respectively. In 2 cases of Ph-negative CML, one case that had karyotype such as 46,XY,t(9;18) showed positive hybridization, the other case with 46,XY,inv(2) showed negative result. CONCLUSION The result demonstrates that D-FISH technique is reliable for detecting bcr/abl fusion gene. The existence of negative bcr/abl fusion gene CML implies that some other initial events inducing CML might have occurred in such cases.
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88
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Xu J, Yang H, Wu J, Lai X, Liu B. [A Carnobacterium-like organism isolated form a patient with multiple bacterial synergistic gangrene]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 2000; 40:21-5. [PMID: 12548873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
An atypical lactic-acid producing gram positive rod Y6 strain was studied in this report, which was isolated form clinic sample of a patient with multiple bacterial synergistic gangrene, and could not be identified by routine method. A 1.5 kb of 16S rDNA of Y6 strain was synthesized and sequenced. Comparative 16S rDNA sequence analyses revealed that stain Y6 is most closely related to the genus of Carnobacterium. The overall similarity value between Y6 strain and Carnobacterium species are 93% to 97%. The signature nucleotides in 16S rDNA primary sequence of strain Y6 and that of genus of Carnobacterium were identical. The biological features of Y6 strain are very similar to that of Carnobacterium, such as lactic acid as main end product of in PYG broth, no gas produced form fermentation of glucose, catalase negative, no motility. Data suggested that Y6 strain is very similar to the genus of Carnobacterium, of which no strain has been isolated form clinical sample so far. Based on the results obtained, we names Y6 strain as Carnobacterium-like organism.
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89
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90
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Correas JM, Burns PN, Lai X, Qi X. Infusion versus bolus of an ultrasound contrast agent: in vivo dose-response measurements of BR1. Invest Radiol 2000; 35:72-9. [PMID: 10639038 DOI: 10.1097/00004424-200001000-00008] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
RATIONALE AND OBJECTIVES To determine the efficacy of an ultrasound contrast agent infusion using Doppler intensitometry estimation of backscatter enhancement in blood. METHODS Multiple intravenous injections of BR1 (SonoVue) were performed in chronic dog studies, using bolus (0.05-2 mL) and infusion (3-40 mL/h during 6 minutes) administration. The pulsed Doppler signal from the femoral artery was recorded and analyzed for mean Doppler power and integrated fractional enhancement. RESULTS For bolus injection, time-intensity curves exhibited a rapid first pass (peak 30 dB for 0.45 mL) followed by a slower washout. Integrated fractional enhancement exhibited a linear relation with the dose (R2 = 0.99). For infusion administration, peak enhancement increased with the infusion rate from 8 to 22 dB. At rates exceeding 30 mL/h, the enhancement was stable with a plateau-like pattern. CONCLUSIONS Infusion of BR1 is easily achieved and allows the duration of enhancement to be increased as long as desired. Stable enhancement is obtained for rates greater than 30 mL/h.
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91
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Luo K, St. Clair TP, Lai X, Goodman DW. Silver Growth on TiO2(110) (1 × 1) and (1 × 2). J Phys Chem B 1999. [DOI: 10.1021/jp993062o] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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92
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Lai X, Feng S, Jin R, Zhang J. The effect of electroacupuncture on auditory P300 potential in mongolism cases. J TRADIT CHIN MED 1999; 19:259-63. [PMID: 10921128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
In treating children with mongolism (Down's syndrome) with electroacupuncture, the latent period of P3 is shortened, which shows that the cerebral reaction to external stimulus in classification, encoding and recognition is accelerated. Along with the elevated P3 amplitude, the cerebrum is more capable of processing the external information, showing improvement of the mental state.
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93
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Wang S, Lai X, Lao J. The third lumbar transverse process syndrome treated by electroacupuncture at huatuojiaji points. J TRADIT CHIN MED 1999; 19:190-4. [PMID: 10921148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
32 cases of the third lumbar transverse process syndrome were treated mainly by electroacupuncture at Huatuojiaji points of the first and second lumbar vertebrae, and another 30 cases of the syndrome by conventional acupuncture as the controls. The results showed that treatment by electroacupuncture at Huatuojiaji points was superior in analgesic effect and clinical total effective rate to that by conventional acupuncture. It is considered that the mechanism of treatment by electroacupuncture at Huatuojiaji points is related to the trunk of posterior ramus of the spinal nerve where the points are located.
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94
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Ding P, Zhen Y, Lai X, Xu H. [Effects of places and stages on the contents of ganoderic acid B from Ganoderma lucidum]. ZHONG YAO CAI = ZHONGYAOCAI = JOURNAL OF CHINESE MEDICINAL MATERIALS 1999; 22:271-2. [PMID: 12575063] [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 paper reports the assay of ganoderic acid B from Ganoderma lucidum in different places and stages by means of HPLC. The results show that contents of ganoderic acid B from different cultured places have differnces, different stages have effect on the amount too.
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95
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Lai X, Zhu W, Yuan G. [Kinetics of the Ca(2+)-activated K+ channel in Ca2+ induced cortex neurons damage]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1999; 30:151-4. [PMID: 12212044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
Ca(2+)-activated K+ channels were studied by using the patch clamp technique of single channel recordings from the primary culture fetal SD rat cortex neurons. Besides their physiologic characters, the effects of increasing cytosolic and cytoplasmic Ca2+ triggered neuronal damage were also studied. The results showed that Kca with conductance around 170PS was predominant in the rat cortex neurons. These channels almost did not open at physiologic intracellular free Ca2+ concentration (10(-8) mol/L), but was extremely activated at intracellular free Ca2+ concentration (10(-6) mol/L). So the open probabilities of the KCa in the cortex neurons obviously depended on the concentration of cytoplasmic Ca2+ and membrane potential. The KCa activated by increasing of intracellular Ca2+ during the early stage of anoxia may be a protective reaction of ischemic neurons.
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96
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Lai X, Torp H. Interpolation methods for time-delay estimation using cross-correlation method for blood velocity measurement. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 1999; 46:277-290. [PMID: 18238424 DOI: 10.1109/58.753016] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The cross-correlation method (CCM) for blood flow velocity measurement using Doppler ultrasound is based on time delay estimation of echoes from pulse-to-pulse. The sampling frequency of the received signal is usually kept as low as possible in order to reduce computational complexity, and the peak in the correlation function is found by interpolating the correlation function. The parabolic-fit interpolation method introduces a bias at low sampling rate to the ultrasound center frequency ratio. In this study, four different methods are suggested to improve the estimation accuracy: (1) Parabolic interpolation with bias-compensation, derived from a theoretical signal model. (2) Parabolic interpolation combined with linear filter interpolation of the correlation function. (3) Parabolic interpolation to the complex correlation function envelope. (4) Matched filter interpolation applied to the correlation function. The new interpolation methods are analyzed both by computer simulated signals and RF-signals recorded from a patient with time delay larger than 1/f(0), where f(0) is the center frequency. The simulation results show that these methods are more accurate than the parabolic-fit method. From the simulation, the worst estimation accuracy is about 1.25% of 1/f(0) for the parabolic-fit interpolation, and it is improved by the above methods to less than 0.5% of 1/f(0) when the sampling rate is 10 MHz, the center frequency is 2.5 MHz and the bandwidth is 1 MHz. This improvement also can be observed in the experimental data. Furthermore, the matched filter interpolation gives the best performance when signal-to-noise ratio (SNR) is low. This is verified both by simulation and experimentation.
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97
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Lai X, Mo F, Jiang G. [Observation of clinical effect of acupuncture on vascular dementia and its influence on superoxide dismutase, lipid peroxide and nitric oxide]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 1998; 18:648-51. [PMID: 11477855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
OBJECTIVE To observe the clinical effect of electroacupuncture and acupuncture on vascular dementia (VaD) and the influence on superoxide dismutase (SOD), lipid peroxide (LPO) and nitric oxide (NO) levels. METHODS Forty-six cases of VaD were randomly divided into two groups, the electroacupuncture group (EA group) and the acupuncture group (AP group). Assessment of Hasgawa's dementia scale (HDS), functional activities questionnaire (FAQ) and neurologic deficit scoring were done before and after treatment, and the changes on SOD, LPO and NO levels were observed. RESULTS After treatment, in the EA group, the HDS elevated, the FAQ lowered, SOD increased and LPO and NO decreased significantly, as compared with before treatment, P < 0.01. But these parameters were not changed significantly in the AP group after treatment. The clinical symptoms were improved in both groups, but the reduction on neurologic deficit score was not significant. The total effective rate of the EA group was higher than that of the AP group. CONCLUSION The immediate effect of electroacupuncture was superior to that of acupuncture, suggesting that the electroacupuncture was more effective in promoting the intelligence recovery than acupuncture.
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98
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Valden M, Lai X, Goodman DW. Onset of catalytic activity of gold clusters on titania with the appearance of nonmetallic properties. Science 1998; 281:1647-50. [PMID: 9733505 DOI: 10.1126/science.281.5383.1647] [Citation(s) in RCA: 2192] [Impact Index Per Article: 84.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Gold clusters ranging in diameter from 1 to 6 nanometers have been prepared on single crystalline surfaces of titania in ultrahigh vacuum to investigate the unusual size dependence of the low-temperature catalytic oxidation of carbon monoxide. Scanning tunneling microscopy/spectroscopy (STM/STS) and elevated pressure reaction kinetics measurements show that the structure sensitivity of this reaction on gold clusters supported on titania is related to a quantum size effect with respect to the thickness of the gold islands; islands with two layers of gold are most effective for catalyzing the oxidation of carbon monoxide. These results suggest that supported clusters, in general, may have unusual catalytic properties as one dimension of the cluster becomes smaller than three atomic spacings.
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99
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Chen L, Qu L, Shi S, Li Z, Lai X. [Differentiation of original plants of xihuangcao by using random amplified polymorphic DNA (RAPD) markers]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1998; 23:328-30, 382. [PMID: 11601294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Four original plants of Xihuangcao have been differentiated from each other by random amplified polymorphic DNA polymorphism. The results show that RAPD technique is an effective method for identification and quality study of Chinese medicinal materials.
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100
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Ingram LO, Gomez PF, Lai X, Moniruzzaman M, Wood BE, Yomano LP, York SW. Metabolic engineering of bacteria for ethanol production. Biotechnol Bioeng 1998. [DOI: 10.1002/(sici)1097-0290(19980420)58:2/3%3c204::aid-bit13%3e3.0.co;2-c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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