10301
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Zhu GF, Liu ZH, Wang J. Improved technic for dengue virus micro cell culture. Chin Med J (Engl) 1984; 97:73-4. [PMID: 6428838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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10302
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Wang J, Greene B, Morgan C. Carbon paste electrodes modified with cation-exchange resin in differential pulse voltammetry. Anal Chim Acta 1984. [DOI: 10.1016/s0003-2670(00)84809-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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10303
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Wang J, Galil KA, Setchell BP. Changes in testicular blood flow and testosterone production during aspermatogenesis after irradiation. J Endocrinol 1983; 98:35-46. [PMID: 6408218 DOI: 10.1677/joe.0.0980035] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Exposure of the testes of anaesthetized adult rats to 527 rads of gamma-irradiation caused testis weight to fall slowly at first and then more rapidly from 21 days afterwards, reaching a minimum at 52 days, when spermatogenesis was severely disrupted. The weights of the accessory organs and the concentrations of testosterone in peripheral blood were slightly reduced; the concentrations in blood from the testicular veins were lower than control at shorter intervals after irradiation, but at later times tended to be similar or greater than control. Testicular blood flow per testis followed testis weight closely, and as a result the production of testosterone by the smaller testes (calculated as the product of plasma flow and the veno-arterial difference in testosterone concentration) was markedly reduced especially when the rats had been stimulated with human chorionic gonadotrophin (hCG). Serum FSH and LH rose appreciably as testis weight fell but there was a proportionately greater rise in FSH than LH, in comparison with surgically castrated animals. Increased amounts of extratubular, extracellular fluid were found in the aspermatogenic testes, but injection of hCG still caused increases in capillary permeability and the amount of fluid in the testis. These results indicate that during aspermatogenesis following irradiation (as with heat and efferent duct ligation) the capacity of the testes to secrete testosterone is severely limited by decreased testicular blood flow, not by the ability of the Leydig cells to release testosterone into their immediate environment.
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10304
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Qin WZ, Zhu GD, Yang SM, Han KY, Wang J. Clinical observations on Tripterygium wilfordii in treatment of 26 cases of discoid lupus erythematosus. J TRADIT CHIN MED 1983; 3:131-2. [PMID: 6555446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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10305
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Wang J. Evaluation of differential pulse voltammetry at carbon electrodes. Talanta 1983; 30:317-22. [DOI: 10.1016/0039-9140(83)80073-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/1982] [Accepted: 12/08/1982] [Indexed: 10/18/2022]
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10306
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Presta E, Wang J, Harrison GG, Björntorp P, Harker WH, Van Itallie TB. Measurement of total body electrical conductivity: a new method for estimation of body composition. Am J Clin Nutr 1983; 37:735-9. [PMID: 6846211 DOI: 10.1093/ajcn/37.5.735] [Citation(s) in RCA: 73] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
A new method for the estimation of body composition in human subjects is described which entails the measurement of total body electrical conductivity. The method is based on the principle that the electrical conductivity of lean tissue is far greater than that of fat. Comparative studies in 19 adults of widely varying fatness have demonstrated excellent correlations between the total electrical conductivity of the subjects and both their total body water (r = 0.87) and total body potassium (r = 0.86). This noninvasive method, which is safe, simple, rapid, and convenient, should prove useful in the nutritional assessment of individuals and populations.
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10307
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Bernstein RS, Thornton JC, Yang MU, Wang J, Redmond AM, Pierson RN, Pi-Sunyer FX, Van Itallie TB. Prediction of the resting metabolic rate in obese patients. Am J Clin Nutr 1983; 37:595-602. [PMID: 6340455 DOI: 10.1093/ajcn/37.4.595] [Citation(s) in RCA: 116] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Resting metabolic rate (RMR) was measured in 154 women and 48 men before the beginning of a weight reduction program. In both sexes there were significant univariate correlations between RMR and fat-free mass, body fat, weight, fat cell weight, and fat cell number (from total body water). Women also showed significant correlations between RMR and fat cell number (from total body potassium), free triiodothyronine index, and fasting and postglucose insulin levels. Multiple regression analysis showed that both fat-free mass and fat cell weight and number were significant predictors of RMR. The contribution of fat-free mass was three to five times greater per kg than that of body fat. There was no significant contribution of thyroid hormones or insulin to the prediction of RMR. Fat cell number and fat cell weight were significant predictors of RMR, whether determined from body water, body potassium, or a formula using both water and potassium. There was no significant difference in regression coefficients between men and women. Thus the difference in RMR between the sexes is probably caused by the higher proportion of fat-free mass in men. The effect of age was small and not statistically significant.
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10308
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Rubin JR, Wang J, Sundaralingam M. X-ray diffraction study of the zinc(II) binding sites in yeast phenylalanine transfer RNA. Preferential binding of zinc to guanines in purine-purine sequences. BIOCHIMICA ET BIOPHYSICA ACTA 1983; 756:111-8. [PMID: 6337651 DOI: 10.1016/0304-4165(83)90030-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
An X-ray diffraction study of a zinc(II) complex of tRNAPhe from yeast reveals the present of five zinc-binding sites on the tRNA molecule. Two of the cooperatively bound Mg2+ in the native tRNA structure are replaced by Zn2+. The remaining sites involve direct coordination of zinc to the N7 position of tRNA guanine bases, G15, G43 and HG45. Thus, zinc displays a high specificity for binding to guanine bases in purine-purine sequences.
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10309
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Wang J, Hutchins L, Selim S, Cumming L. Catheter microelectrode assembly for in-vivo and in-vitro voltammetric analysis of body fluids. Talanta 1983; 30:121-3. [DOI: 10.1016/0039-9140(83)80030-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/1982] [Accepted: 09/24/1982] [Indexed: 11/26/2022]
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10310
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Lewis M, Jeffrey A, Wang J, Ladner R, Ptashne M, Pabo CO. Structure of the operator-binding domain of bacteriophage lambda repressor: implications for DNA recognition and gene regulation. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 1983; 47 Pt 1:435-40. [PMID: 6305562 DOI: 10.1101/sqb.1983.047.01.051] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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10311
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Hogan M, Wang J, Austin RH. Triplet anisotropy decay measurements of DNA internal motion. CIBA FOUNDATION SYMPOSIUM 1983; 93:226-245. [PMID: 6551228 DOI: 10.1002/9780470720752.ch13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Triplet anisotropy decay techniques have been used to measure the internal flexibility and overall rotational motions of DNA over a time range of 15 ns to 200 microseconds. Nearly monodisperse DNA fragments with lengths varying from 65 to 600 base pairs were studied using the intercalating dye methylene blue as a triplet probe. The slow end-over-end tumbling of short DNA fragments (less than 165 base pairs) is as predicted for a rigid rod. As expected, a longer DNA fragment (600 base pairs) experiences slow segmental motions of its helix axis. At the earliest times, anisotropy decays more rapidly than expected for a rigid rod, suggesting that, when it is bound, methylene blue monitors fast internal motions of the helix. Since the rod-like end-over-end tumbling rules out fast bending motions (for short DNA fragments), the fast components of DNA anisotropy decay must be due to twisting motions of the helix, occurring with a time constant near 50 ns. The same techniques were used to measure the conformational flexibility of DNA in the nucleosome. It is concluded that, when the DNA helix is wrapped to form a nucleosome, it experiences substantial internal flexibility, occurring with a time constant near 30 ns. The amplitude and time-scale of this motion appear to be similar to that seen in the uncomplexed DNA helix.
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10312
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Abstract
We have used time-resolved triplet state anisotropy decay techniques to measure the conformational flexibility of DNA in the nucleosome. From these measurements we conclude that, in a nucleosome, the DNA helix experiences substantial internal flexibility, which occurs with a time constant near 30 nsec. We find that our data can be fit well by a modified version of the Barkley-Zimm model for DNA motion, allowing only DNA twisting motions and the overall tumbling of the nucleosome. That fit yields a calculated torsional rigidity equal to 1.8 X 10(-19) erg X cm, a value equal to that measured for uncomplexed DNA. We conclude from such similarity that large, fast twisting motions of the DNA helix persist, nearly unaltered, when DNA is wrapped to form a nucleosome.
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10313
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Wang J. [A discussion of some problems on hemoptysis]. ZHONGHUA JIE HE HE HU XI XI JI BING ZA ZHI = CHINESE JOURNAL OF TUBERCULOSIS AND RESPIRATORY DISEASES 1982; 5:294-6. [PMID: 7166094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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10314
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Wang J, Han M, Bao YF, Qu J, Zhang Y. [Detection of malaria antibodies with micro-ELISA]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 1982; 4:319-21. [PMID: 6219770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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10315
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Hu R, Wang J, Lei K. Isolation and properties of L-amino acid oxidase from Ophiophagus hannah venom. SCIENTIA SINICA. SERIES B, CHEMICAL, BIOLOGICAL, AGRICULTURAL, MEDICAL & EARTH SCIENCES 1982; 25:941-52. [PMID: 7146872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
This paper reports the isolation and some properties of L-amino acid oxidase from Ophiophagus hannah venom. The differences between L-amino acid oxidase from Ophiophagus hannah and that from other sources in specific activity, properties and the spectrum of isozymes are noticeable. The result of electrophoresis on polyacrylamide gel shows that this purified enzyme is homogenous. The molecular weight determined by gradient polyacrylamide gel slab (4--30%) is around 15 X 10(4) dalton. The molecular weight of the subunit determined by SDS gradient gel electrophoresis (4--30%) is around 7.3 X 10(4) dalton. Therefore, this enzyme is composed of two subunits. The absorption spectrum reveals that there are two FADs in each molecule. The optimum pH of enzymic reaction is around 8.7--9.0 when L-leucine is used as substrate. The inhibition of the products is noticeable when substrate concentration goes beyond 3mM. This enzyme is heat stable and its activity would not decrease obviously after heating at 55 degrees C for 40 min. A linear relationship between enzyme concentration and reaction rate was noticed when enzyme concentration was below 5.7 micrograms/ml.
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10316
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Hogan M, Wang J, Austin RH, Monitto CL, Hershkowitz S. Molecular motion of DNA as measured by triplet anisotropy decay. Proc Natl Acad Sci U S A 1982; 79:3518-22. [PMID: 6954497 PMCID: PMC346452 DOI: 10.1073/pnas.79.11.3518] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
We have used triplet anisotropy decay techniques to measure the internal flexibility and overall rotational motion of DNA, covering a time range from 15 ns to 200 mus. Nearly monodisperse DNA fragments 65--600 base pairs long were studied by using the intercalating dye methylene blue as a triplet probe. We found that the slow end-over-end tumbling of short DNA fragments (less than or equal to 165 base pairs) is as predicted for a rigid rod. As expected, a longer DNA fragment (600 base pairs) experiences slow segmental motion of its helix axis. We found that, at the earliest times, anisotropy decays more rapidly than expected for a rigid rod, suggesting that, when bound, methylene blue monitors fast internal motion of the helix. Since the rod-like end-over-end tumbling of short fragments rules out fast bending motions, we conclude that the fast components of DNA anisotropy decay are due to twisting motion of the helix, occurring with a time constant near 50 ns.
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10317
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Colt EW, Dunner DL, Wang J, Ross DC, Pierson RN, Fieve RR. Body composition in affective disorder before, during, and after lithium carbonate therapy. ARCHIVES OF GENERAL PSYCHIATRY 1982; 39:577-81. [PMID: 6807255 DOI: 10.1001/archpsyc.1982.04290050051010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The body composition of three unipolar and 17 bipolar patients, studied during the depressive state, was compared with that of 48 controls. The ratio of extracellular to intracellular water content was significantly less in male patients than in male controls: the difference between female patients and female controls was not statistically significant. In patients of both sexes, residual sodium concentration was greater in patients than in controls. The intracellular content of potassium was the same in patients as in controls. In six patients, body composition was studied prior to lithium carbonate therapy, after 17 days of treatment, and 17 days after discontinuing administration of the drug. The significant changes were a decrease in body weight during therapy, and a decrease in body water content and an increase in residual sodium concentration after drug treatment was discontinued.
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10318
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Wang J. Anodic stripping voltammetry as an analytical tool. ENVIRONMENTAL SCIENCE & TECHNOLOGY 1982; 16:104A-9A. [PMID: 22656200 DOI: 10.1021/es00096a724] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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10319
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Pierson RN, Wang J, Colt EW, Neumann P. Body composition measurements in normal man: the potassium, sodium, sulfate and tritium spaces in 58 adults. JOURNAL OF CHRONIC DISEASES 1982; 35:419-28. [PMID: 7076785 DOI: 10.1016/0021-9681(82)90056-x] [Citation(s) in RCA: 77] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The aqueous phase of total body composition varies with sex, and changes with age, necessitating age, sex and method-specific normal values. Consensus has developed for the methods most suited to clinical studies. 3H20 for water, 35SO4 for ECW, 24Na for NAc, and 40K for body potassium were used in 58 normal volunteers aged 19-80, 30 men and 28 women. This report shows significant age regressions in both sexes for total body water and intracellular water, and for both Na and K when referenced to body water. Combination of these findings with the highly age related decrease in total body potassium confirms previous studies that body cell mass decreases with age. Intracellular K+ and Na+ at the zero age intercept are 130 and 14.5 for males, and 124 and 24mEq/1 for females respectively. Secular decrease in K+ and increase in Na+ concentrations in the average cell are suggested although not established. Values for normal body composition, in subjects healthy by all available criteria are in some instances age and sex dependent, but in all parameters except fat show wide normal range (SD = 7% of mean) which derive more from biological variation than from limitations of measurement precision. However, use of body water rather than weight succeeds in narrowing this wide range, and is a more logical denominator which is readily subject to accurate measurement. In serial studies of the same subject, significant changes can be measured which are well within the normal range.
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10320
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10321
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Damber JE, Selstam G, Wang J. Inhibitory effect of estradiol-17 beta on human chorionic gonadotropin-induced increment of testicular blood flow and plasma testosterone concentration in rats. Biol Reprod 1981; 25:555-9. [PMID: 7306640 DOI: 10.1095/biolreprod25.3.555] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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10322
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Yu YP, Jin ZY, Wang J, Chen BZ. Effect of "Qingshen" No. 1 in 50 cases of simple obesity. J TRADIT CHIN MED 1981; 1:55-60. [PMID: 6926693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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10323
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Pabo C, Wang J, Jeffrey A, Itakura K. Co-crystallization of repressor and operator fragments from bacteriophage lambda. Acta Crystallogr A 1981. [DOI: 10.1107/s0108767381098188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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10324
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10325
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Austin L, Shah J, Wang J, Gallagher E, Luckie P. An analysis of ball-and-race milling. Part I. The hardgrove mill. POWDER TECHNOL 1981. [DOI: 10.1016/0032-5910(81)87029-5] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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