7101
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7102
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Weetman AP, Zhang L, Webb S, Shine B. Analysis of HLA-DQB and HLA-DPB alleles in Graves' disease by oligonucleotide probing of enzymatically amplified DNA. Clin Endocrinol (Oxf) 1990; 33:65-71. [PMID: 2401099 DOI: 10.1111/j.1365-2265.1990.tb00466.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We have tested the possible association of HLA-DQB and HLA-DPB alleles with Graves' thyrotoxicosis, with or without severe ophthalmopathy, by polymerase chain amplification of genomic DNA and allele-specific oligonucleotide probing. There was no significantly abnormal distribution of DQB alleles compared to 50 control subjects except for a reduced prevalence of DQw 3.1 in the Graves' patients with severe ophthalmopathy (X2 = 6.23, P less than 0.02). HLA-DPB 2.1/8 was found in only 1 of 40 of these patients compared with 15 of the controls (X2 = 11.49, P less than 0.001). Ten of 48 patients with Graves' disease but without clinically significant eye involvement were HLA-DPB 2.1/8 positive, not significantly different from controls, but significantly different from the ophthalmopathy group (X2 = 6.70, P less than 0.01). The other DPB alleles in both groups of Graves' disease patients were the same as controls. These results suggest that HLA-DPB 2.1/8 may confer a protective effect in Graves' disease with respect to ophthalmopathy.
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7103
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Li H, Yang H, Xie S, Zhang L, Li C. Treatment of idiopathic edema with decoction of radix Aucklandiae for promoting flow of QI--analysis of 50 cases. J TRADIT CHIN MED 1990; 10:114-5. [PMID: 2391991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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7104
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Li SG, Ottenhoff TH, Van den Elsen P, Koning F, Zhang L, Mak T, De Vries RR. Human suppressor T cell clones lack CD28. Eur J Immunol 1990; 20:1281-8. [PMID: 2164478 DOI: 10.1002/eji.1830200613] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Previously we showed that certain T cell lines and clones from a lepromatous leprosy patient displayed a dose-dependent suppression of the proliferation of autologous T cells to Mycobacterium leprae (M. leprae) but not mitogen or an unrelated antigen. The latter cells were also cloned and did not display this suppressive activity, were CD4+ and proliferated vigorously to M. leprae presented by autologous HLA-DR molecules. We shall refer to these cells as T helper (Th) cells. Most of the suppressive T cell clones (Ts) were also CD4+ and also proliferated to M. leprae presented by HLA-DR, but much less strongly than Th cells. In this study we report on our search for (a) the mechanism of this apparently antigen-specific suppression by T cells, and (b) a possible phenotypic difference between Th and Ts clones. The two main conclusions are that Ts clones possess a lytic machinery, but that M. leprae-specific suppression and cytotoxicity can be clearly dissociated, and that the only phenotypic difference between Th and Ts is the presence of the CD28 marker on Th and its absence on Ts clones.
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MESH Headings
- Antigens, CD/analysis
- Antigens, Differentiation, T-Lymphocyte/analysis
- Antigens, Differentiation, T-Lymphocyte/biosynthesis
- CD28 Antigens
- CD3 Complex
- Clone Cells
- Flow Cytometry
- Humans
- Leprosy, Borderline/immunology
- Lymphocyte Activation/immunology
- Mycobacterium leprae/immunology
- Phenotype
- Receptors, Antigen, T-Cell/biosynthesis
- T-Lymphocytes, Helper-Inducer/immunology
- T-Lymphocytes, Regulatory/immunology
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7105
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Zhang L, Dyer DC. Characterization of 5-hydroxytryptamine receptors on isolated ovine uterine artery in late pregnancy. J Pharmacol Exp Ther 1990; 253:1236-44. [PMID: 2359025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
5-Hydroxytryptamine (5-HT) and 2,5-dimethoxy-4-methyl-amphetamine (DOM) are potent agonists on isolated ovine uterine arteries in late pregnancy. Similar pA2 values (8.56 and 8.33, respectively) of ketanserin, tested against 5-HT and DOM, indicate that responses produced by both agonists are mediated by the 5-HT2 receptor. The contractions produced by 8-OH-DPAT and 2-methyl-5-HT were also blocked by ketanserin (10(-8) M) with the dissociation constants (KB) being 2.49 and 2.88 nM, respectively. This provides evidence that these agonists are activating 5-HT2 receptors in the ovine uterine artery. DOM was more potent than 5-HT, but had a similar efficacy to that of 5-HT. The greater affinity of DOM may explain its greater potency. The dissociation constants (KA) of 5-HT and DOM acting on 5-HT receptors were determined by analysis of concentration-response data before and after fractional inactivation of receptors with dibenamine. The mean KA values for 5-HT and DOM were 3.7 +/- 0.7 x 10(-7) and 1.8 +/- 0.3 x 10(-7) M, respectively. Assessment of receptor occupancy vs. functional response demonstrated little or no receptor reserve in this tissue. Several other 5-HT receptor agonists caused contractions but were much less potent than 5-HT. The order of potency of these agonists was determined to be DOM greater than 5-HT greater than or equal to alpha-methyl-5-HT much greater than 8-hydroxy-dipropylaminotetralin (8-OH-DPAT) greater than 2-methyl-5-HT greater than 1-(3-chlorophenyl) piperazine (mCPP) greater than m-trifluoromethyl-phenylpiperazine (TFMPP).(ABSTRACT TRUNCATED AT 250 WORDS)
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7106
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Liu B, He Y, Zhang R, Zhang L, Fan P, Peng T, Liu Y. [Effect of high carbohydrate and high fat diets on plasma glucose, insulin and lipids in normal and hypertriglyceridemic subjects]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1990; 21:145-9. [PMID: 2202650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The fasting plasma glucose, insulin and lipids response to high-carbohydrate-low-fat diets and low-carbohydrate-high-fat diets in normal subjects and patients with endogenous hypertriglyceridemia was observed. The normal, high carbohydrate and high fat diets consisted of 60%, 80% and 40% carbohydrate, 25%, 5% and 45% fat and 15% protein of total calorie respectively. The fasting plasma glucose levels increased (P less than 0.01) on day 1, insulin increased on day 3 (P less than 0.01 and P less than 0.05) and TG levels increased on days 3 and 5 after taking high carbohydrate diets both in the normal and hypertriglyceridemic groups. The fasting plasma TC and HDL-C decreased on high carbohydrate diets mainly in the hypertriglyceridemic group. The fasting plasma glucose slightly decreased on day 5, TG decreased on day 1 (P less than 0.05) and TC increased on day 1 and 3 (P less than 0.01) after taking high fat diets, but no differences were observed in insulin levels. Fasting plasma HDL-C levels in the normal group remained unchanged, but significantly decreased 3 days after taking high fat diets in the hypertriglyceridemic group (P less than 0.001). Our results indicate that high carbohydrate intake may be an important cause of hypertriglyceridemia in our country. This diet may cause a slight increase in the blood glucose level, which in turn stimulates an increase in plasma lipids and decrease in HDL-C, which is associated with an increase in the incident of coronary heart disease.(ABSTRACT TRUNCATED AT 250 WORDS)
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7107
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Ren L, Xu J, Ma J, Zhang H, Zhuang B, Zhang L. [Antitumor action of lignum sappan]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1990; 15:306-7, 320. [PMID: 2275786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The aqueous extract of lignum sappan can kill cell lines of HL-60, K562, L929 and Yac-1 at the concentration of 2 microliters/ml. The survival time of mice bearing EAC is increased by 185% (P less than 0.01) by ip 0.2 ml/mouse x 7d. The three-stage sequential test standard can be passed smoothly.
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MESH Headings
- Animals
- Carcinoma, Ehrlich Tumor/drug therapy
- Drugs, Chinese Herbal/pharmacology
- Drugs, Chinese Herbal/therapeutic use
- Fabaceae
- Female
- Humans
- Leukemia, Erythroblastic, Acute/pathology
- Leukemia, Promyelocytic, Acute/pathology
- Male
- Mice
- Neoplasms, Experimental/pathology
- Plants, Medicinal
- Tumor Cells, Cultured/drug effects
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7108
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Zhang L, Barrett JE. Interactions of corticotropin-releasing factor with antidepressant and anxiolytic drugs: behavioral studies with pigeons. Biol Psychiatry 1990; 27:953-67. [PMID: 1970744 DOI: 10.1016/0006-3223(90)90033-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A number of studies have shown significant interactions between neuronal systems involved with corticotropin-releasing factor (CRF) and either the clinical manifestations of depression and anxiety or the effects of antidepressant or anxiolytic drugs. In the present study, effects of CRF were studied alone and in combination with imipramine and with the sedative-hypnotic/anxiolytic drugs pentobarbital and chlordiazepoxide. Interactions of CRF with the novel, atypical anxiolytic buspirone were also examined. Interactions were evaluated through the use of schedule-controlled responding, responding suppressed by punishment, and drug discrimination procedures using the conditioned key-pecking response of pigeons. Effects of CRF were significantly enhanced when given in combination with imipramine with low noneffective imipramine doses potentiating the rate-reducing effects of CRF. Similarly, in pigeons trained to discriminate imipramine from saline, noneffective doses of CRF shifted the imipramine dose-response curve more than twofold to the left. Low doses of imipramine that produced saline key responding, produced imipramine-key responding when coadministered with CRF. The CRF antagonist alpha-helical CRF9-41 did not alter the rate-decreasing effects of imipramine. Effects of CRF on schedule-controlled responding were, however, antagonized by the administration of chlordiazepoxide and pentobarbital but not by buspirone, suggesting that CRF interacts with the GABA/benzodiazepine receptor mechanism complex but not with those systems involved in mediating the effects of buspirone. These results suggest that CRF interacts in significant ways with specific neurotransmitter systems subserving depression and anxiety.
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7109
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Zhang L, Gralla JD. In situ nucleoprotein structure involving origin-proximal SV40 DNA control elements. Nucleic Acids Res 1990; 18:1797-803. [PMID: 2159622 PMCID: PMC330598 DOI: 10.1093/nar/18.7.1797] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Nucleoprotein structures at the SV40 GC-box and adjacent AT-rich region have been probed by nucleases in permeabilized cells at nucleotide level resolution. The patterns of nuclease protection and hypersensitivity in these permeabilized cells that allow initiation of RNA and DNA synthesis are quite different from those observed in isolated nuclei that are inactive. Whereas simple DNA protection by factors is found in nuclei, the pattern in permeabilized cells includes very strong nuclease hypersensitive sites. Their arrangement suggests that the region exists as a higher order nucleoprotein complex in vivo, which is disturbed during the preparation of nuclei. The pattern is also found to be disturbed in permeabilized cells when T-antigen is inactivated by temperature-sensitive mutation. Since T-antigen origin binding sites and the GC-box region have been shown previously to interact functionally, the existence of a higher order structure involving both components provides a likely physical basis for the functional interaction of separate control elements.
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7110
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Liu ZQ, Ma AQ, Zhang L, Yang DY. Intra-cellular electrolyte changes and levels of endogenous digoxin-like substance within the plasma in patients with congestive heart failure. Int J Cardiol 1990; 27:47-53. [PMID: 2159446 DOI: 10.1016/0167-5273(90)90190-g] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In this study, the lymphocytes and erythrocytes from peripheral venous blood were used as the study model from which were measured the cellular contents of potassium, sodium, calcium and magnesium in 50 patients with chronic congestive heart failure and 39 control patients. Levels of endogenous digoxin-like substance in the plasma and activities of Na/K ATPase in red cell membrane wer monitored simultaneously. In the patients with heart failure, the intracellular contents of potassium and magnesium were decreased while those of sodium and calcium were increased significantly. The levels of endogenous digoxin-like substance were much higher in the plasma than those either in healthy controls or in patients with heart disease but without congestive failure (273.7 +/- 35.5 vs 23.3 +/- 2.2 and vs 32.9 +/- 3.6 pg/ml, respectively, P less than 0.001 for both). The activities of Na/K-ATPase were much lower in the patients with heart failure than in the controls. Values for intracellular electrolytes were significantly correlated with the rising levels of digoxin-like substance in the plasma. Non-digitalis inotropic therapy was associated with the recovery of these alterations of heart function, with the levels of the digoxin-like substance decreasing and activity of Na/K-ATPase going up. We conclude that endogenous digoxin-like substance might play a role in the imbalance of intra-cellular electrolytes seen in patients with congestive heart failure. Digoxin may exacerbate the loss of intracellular potassium.
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7111
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Zhang L. [Attention to the nursing archives]. ZHONGHUA HU LI ZA ZHI = CHINESE JOURNAL OF NURSING 1990; 25:161-2. [PMID: 2350824] [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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7112
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Li Q, Zhang L, Wu Z. [Diterpenoid constituents in bulbs of Fritillaria anhuiensis S.C. Chen et S.F. Yin]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1990; 15:170-1, 191. [PMID: 2085405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The bulb of Fritillaria anhuiensis, a substitute for the traditional Chinese medicine Beimu, has been used as antibechic and expectorant. From the either soluble part of the bulb, four constituents were isolated and identified by spectral analysis (IR, MS, 1HNMR, 13CNMR) as beta-sitosterol, daucosterol, ent-kaur-15-en-17-ol and ent-kauran-16 beta, 17-diol.
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7113
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Li Y, Wu M, Zhang L, Zhao Q, Zeng Y. [Establishment of hybridoma cell lines producing monoclonal antibodies against-p30 antigen]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1990; 21:12-6. [PMID: 2365336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BALB/c mice were immunized with the purified p30 antigen. SP2/0 myeloma cells and immune spleen cells were fused with 50% PEG (Sigma, MW 3,350-4,000). The cell fusion rate was 93.95%, and the antibody producing rate 21.01%. The technique of limiting dilution was used for cloning of the hybridoma cells. Two hybridoma cell lines E8 and G1 secreting McAb against p30 antigen were obtained. The number of chromosome of both E8 and G1 cell lines was 98.7 +/- 6.54 and 97.7 +/- 7.77, respectively. Results of the PAGE of the ascites generated by the hybridoma cell lines E8 and G1 showed a thick protein band at the gamma-region which was absent from the ascites generated by the SP 2/0 myeloma cells. The immunoglobulin of the McAb E8 and G1 belonged to IgG2 subclass. The results of the immunohistochemical method using the horseradish peroxidase conjugated antibody showed that both E8 and G1 McAb only reacted with epithelial cells of the normal human prostatic glands and their ducts, but did not cross-react with other thirty-four different kinds of normal human tissues. The results of inhibiting ELISA test showed that both E8 and G1 McAb were only inhibited by the human seminal plasma and p30, weakly inhibited by the adult male's urine, but were not inhibited by other eight different kinds of human body fluids and secretions as well as semen from eight different species of animals. It was concluded that McAb of E8 and G1 were organ and species specific.(ABSTRACT TRUNCATED AT 250 WORDS)
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7114
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Chen S, Zhang L. [The fully loaded nursing circuit chart in use]. ZHONGHUA HU LI ZA ZHI = CHINESE JOURNAL OF NURSING 1990; 25:113-4. [PMID: 2322961] [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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7115
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Wang SH, Song Q, Clayman BP, Peng JL, Zhang L, Shelton RN. Energy gaps of Nd1.85Ce0.15CuO4-y and Nd1.85Th0.15CuO4-y determined by far-infrared spectroscopy. PHYSICAL REVIEW LETTERS 1990; 64:1067-1070. [PMID: 10042154 DOI: 10.1103/physrevlett.64.1067] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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7116
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Yang G, Zhang L, Fan L. [Anti-angina effect of puerarin and its effect on plasma thromboxane A2 and prostacyclin]. ZHONG XI YI JIE HE ZA ZHI = CHINESE JOURNAL OF MODERN DEVELOPMENTS IN TRADITIONAL MEDICINE 1990; 10:82-4, 68. [PMID: 2364466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Plasma concentrations of thromboxane B2 (TXB2) and 6-keto-prostaglandin Fl alpha(6-K-PGFl alpha), the stable nonenzymatic metabolites of TXA2 and prostacyclin were assayed in 30 patients suffering from angina pectoris before and after administration of puerarin. In addition, serum lipids and HDL were also measured at the same time. 20 healthy subjects were chosen as the control group. Two weeks before and during administration of puerarin, aspirin, calcium-antagonists, all kinds of hypotensors and drugs relieving chest pain of angina pectoris were strictly prohibited. Puerarin was intravenously given, 500 mg daily for 7 days, which was considered as a therapeutic course. Besides relieving of chest pain, decreasing of heart rate and reduction of blood pressure clinically, it was also found that plasma 6-K-PGFl alpha concentrations were significantly elevated from 38.32 +/- 15.40 to 158. 79 +/- 98.62 pg (P less than 0.01) after administration of puerarin, but there was no significantly difference between plasma TXB2 concentrations before and after administering the drug. In addition, serum HDL was apparently enhanced as compared with that before the administration of puerarin (P less than 0.01). The results indicated that puerarin has the function of anti-angina, reducing both systolic and diastolic blood pressure and diminishing myocardial oxygen consumption.
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7117
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Zhang L, Rinke de Wit TF, Li SG, van Rood JJ, Claas FH. Subtypes of HLA-A1 defined on the basis of CTL precursor frequencies. Hum Immunol 1990; 27:80-9. [PMID: 2298611 DOI: 10.1016/0198-8859(90)90105-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Recently we have shown that limiting dilution analysis can be used to detect cytotoxic T-cell precursor frequencies directed against individual HLA class I antigens. Using the same protocol, we have been able to define two subtypes of HLA-A1, which are indistinguishable by conventional typing sera as well as by cell-mediated lympholysis. One-dimensional isoelectric focusing analysis of the variants did not show any overall charge differences. However, family studies indicated that these HLA-A1 subtypes are genetically determined and can be distinguished on the bases of T-cell precursor frequencies in HLA-A1-negative blood donors.
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7118
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Zhang L. [Magnetic resonance imaging in hypertrophic cardiomyopathy (preliminary experience of 6 cases)]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 1990; 18:13-4, 60-1. [PMID: 2397688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Preliminary experience of magnetic resonance imaging (MRI) in 6 cases of hypertrophic cardiomyopathy (HCM) is described in this article. MRI can provided pertinent pathoanatomic information of this entity and it is of definite value in the diagnostic evaluation of HCM. The relative value of different imaging techniques (such as echocardiography, CT and angiography, etc) in the diagnosis of HCM are also briefly discussed.
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7119
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Yin W, Lu J, Zhang L, Liu G, Liu S. A model for urbanizing rural population and development measures: survey of a large specialized market in Xiliu town, Liaoning province. CHINESE JOURNAL OF POPULATION SCIENCE 1990; 2:25-33. [PMID: 12283756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
The authors present an urbanization model using the example of Xiliu town in Liaoning province, China. Xiliu has developed from a rural commune into a large-scale clothing market during the period since 1979. "The purpose...is to show, by means of a survey conducted in the town, the characteristics and formative factors of the model and to discuss the prospect of and measures for furthering this development."
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7120
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7121
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Hou JL, Lou KX, Zhang L. [Immunohistochemical analysis of HLA class I antigens of the hepatocyte membrane in hepatitis B virus carriers]. ZHONGHUA NEI KE ZA ZHI 1990; 29:29-31, 61. [PMID: 2205450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
HLA class I antigens on hepatocyte membrane were studied in liver biopsies from 46 patients with chronic hepatitis B virus infection by using immunoenzyme technique. The results revealed that the density of HLA class I antigens displayed on hepatocyte membrane in HBeAg positive carriers with minor hepatic inflammatory activity (the high replicative phase) was lower than that in patients with chronic active liver diseases (the low replicative phase) (P less than 0.005), but higher than that in patients with anti-HBe positivity and minor hepatic inflammatory activity (the nonreplicative phase) (P less than 0.05). In a follow-up of 21 HBeAg positive chronic HBV carriers, we found that five of the seven cases with high-density HLA class I antigens showed display of antigens on hepatocyte membrane, whereas only one of the 14 cases with lowdensity antigens were seroconverted from HBe antigen to antibody within one year. These findings suggest that the display on HLA class I antigens on hepatocyte membrane is enhanced and the cytotoxic T lymphacytes can recognize and lyze the infected hepatocytes.
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7122
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Zhang L, Gralla JD. In situ nucleoprotein structure at the SV40 major late promoter: melted and wrapped DNA flank the start site. Genes Dev 1989; 3:1814-22. [PMID: 2558048 DOI: 10.1101/gad.3.11.1814] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
New in situ probing methods have been developed and used to probe the nucleoprotein structures at the SV40 major late promoter in infected monkey cells. The region that contains the three proximal transcription elements was probed with DNase I and micrococcal nuclease in transcriptionally active, permeabilized cells, and with the single-strand selective reagent KMnO4 in intact cells. The downstream element is included in a region of enhanced DNase I reactivity at 10- to 11-bp intervals for approximately 140 bp, presumably because of DNA wrapping around a specifically positioned nucleosome particle. The two other proximal DNA elements appear to be mostly melted, with a protecting factor bound primarily to the template DNA strand. The protecting factor directly borders the wrapped particle. These observations provide an initial description of parts of the biological transcription machinery and suggest that the SV40 major late promoter elements are part of a higher order nucleoprotein complex that involves wrapped and melted DNA.
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7123
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Zhang L, Zhao WK. [Solvent extraction and high performance liquid chromatography with electrochemical detection for determination of plasma catecholamines]. ZHONGGUO YAO LI XUE BAO = ACTA PHARMACOLOGICA SINICA 1989; 10:572-5. [PMID: 2641860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
This paper describes a technique for selectively extracting plasma catecholamines prior to quantification by HPLC-EC. The extraction system was a two-stage process. The first stage involve the complex formation between diphenylbrorate and catechol (diol) groups in alkaline medium. The second stage was a liquid-liquid extraction. The complex combined with tetraoctylammonium bromide to form an ion-pair formation into organic solvent. The catecholamines in turn was extracted with acid. This technique provided a very specific extraction procedure which resulted in chromatograms with few interfering compounds and gave absolute recoveries (100-103%) of norepinephrine, epinephrine and dopamine. Meanwhile, the plasma catecholamines were concentrated and the detective sensitivity was increased. A good linear relationship was found between the concentrations and ratio of peak heights of the catecholamines from 0.125-2 ng. The correlation coefficients ranged from 0.998-0.999. The coefficients of variation of the intra- and inter-assay were within 3 and 6% respectively. The results show that the procedure is very simple and fast. The method is valuable not only for clinical diagnosis but also for laboratory research.
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7124
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Zhang L, Xing LP, Demers L, Washington J, Kauffman GL. Central neurotensin inhibits gastric acid secretion: an adrenergic mechanism in rats. Gastroenterology 1989; 97:1130-4. [PMID: 2551763 DOI: 10.1016/0016-5085(89)91682-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Although parenteral neurotensin (NT) inhibits stimulated gastric acid secretion, published reports on the effect of centrally administered NT on gastric acid secretion are conflicting. This study provides evidence suggesting that, in chronic gastric fistula rats, intracerebroventricularly administered NT (15-60 micrograms) significantly reduces both basal and pentagastrin-, 2-deoxy-D-glucose-, and carbachol-but not histamine-stimulated gastric acid secretion. Using radioimmunoassay, the concentration of plasma immunoreactive NT increased from 30 to 200 pg/ml at 30 and 60 min, respectively after a single intracerebroventricular (i.c.v.) administration of NT at a dose of 60 micrograms. These serum NT concentrations can be reproduced by a constant NT i.v. infusion at 2 micrograms/kg.h. This parenteral infusion dose does not inhibit acid secretion as does i.c.v. NT. Pretreatment with the i.c.v. dopamine-2 receptor antagonists haloperidol or domperidone totally abolishes the inhibitory effect of i.c.v. NT on pentagastrin-stimulated gastric acid secretion. In contrast, pretreatment with the specific dopamine-1 receptor antagonist SCH 23900 or the specific dopamine-2 receptor antagonist sulpiride does not affect i.c.v. NT-induced inhibition of pentagastrin-stimulated gastric acid secretion. Pretreatment (intracerebroventricularly) with the alpha-adrenergic antagonist phentolamine blocks the antisecretory effect of i.c.v. NT. Administration of 3.0 micrograms NT per side directly into nucleus accumbens (NACB), using a stereotaxic technique, significantly reduces basal gastric acid secretion. This effect of central NT is blocked by pretreatment with intra-NACB haloperidol (0.5 microgram per side). These findings suggest that NT acts centrally to inhibit gastric acid secretion, an effect that may occur within NACB and be mediated by central nervous system alpha-adrenergic receptor activation.
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7125
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Vandekerckhove BA, van Bree S, Zhang L, Datema G, Zantvoort F, Claas FH. Increase of donor-specific cytotoxic T lymphocyte precursors after transfusion. Transplantation 1989; 48:672-5. [PMID: 2799922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Cytotoxic T lymphocyte precursor (CTLp) frequencies were determined in the blood of 10 patients before and after transfusion. The male patients were selected from those on the waiting list for a heart or kidney transplantation, who had received no previous blood transfusions and had no panel-reactive antibodies. Both the limiting dilution curves obtained before as well as after transfusion were linear and applied to zero-order kinetics, indicating that only cytotoxic T cells were limiting in the assay. In 9 out of 10 patients CTLp frequencies against the blood donor antigens significantly increased (up to 107 times) compared to the CTLp frequencies measured before transplantation. The CTLp frequencies against controls, sharing no HLA antigens with the blood transfusion donor, were only slightly increased (up to 5 times) in 7 patients and decreased in 3.
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