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31.
G. B. Singh Swaran Nityanand R. C. Srimal V. A. Rao P. C. Jain B. N. Dhawan 《Cellular and molecular life sciences : CMLS》1973,29(12):1529-1530
Zusammenfassung Centpyraquin (3-(-p-fluorobenzyl propyl) 2,3,4,4a,5,6-hexahydro-1(H)-pyrazino (1,2-a) quinoline hydrochloride) zeigte hypotensive Aktivität bei narkotisierten wie auch bei wachen Katzen. Es senkt auch den Blutdruck bei Ratten mit nephrogenem Hochdurck. Die Hypotension scheint auf einem peripheren Mechanismus zu beruhen.
Thanks are due to Drs.M. L. Dhar andN. Anand for their interest in the work.
Communication No. 1600 from the Central Drug Research Institute; Lucknow. 相似文献
Thanks are due to Drs.M. L. Dhar andN. Anand for their interest in the work.
Communication No. 1600 from the Central Drug Research Institute; Lucknow. 相似文献
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Zusammenfassung Nachweis, dass die Blattbehandlung mit subletaler Konzentration von Simazin, Propazin, Igran und Prometon die Protein-Synthese bei Erbse und Mais vermehrt. Die Blattbehandlung mit Simazin zerstörte die Ultrastruktur des Samenlappens bei der Erbse.
This study was supported by the Agriculture Research Service, USDA, Grant No. 12-14-100-9903, administered by the Human Nutrition Division, Beltsville, Maryland. 相似文献
This study was supported by the Agriculture Research Service, USDA, Grant No. 12-14-100-9903, administered by the Human Nutrition Division, Beltsville, Maryland. 相似文献
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Free energy perturbation calculations on binding and catalysis after mutating Asn 155 in subtilisin 总被引:1,自引:0,他引:1
Site-directed mutagenesis is a very powerful approach to altering the biological functions of proteins, the structural stability of proteins and the interactions of proteins with other molecules. Several experimental studies in recent years have been directed at estimating the changes in catalytic properties, (rates of binding and catalysis) in site-directed mutants of enzymes compared to the native enzymes. Simulation approaches to the study of complex molecules have also become more powerful, in no small measure owing to the increase in computer power. These simulations have often allowed results of experiments to be rationalized and understood mechanistically. A new approach called the free-energy pertubation method, which uses statistical mechanics and molecular dynamics can often be used for quantitative calculation of free energy differences. We have applied such a technique to calculate the differential free energy of binding and free energy of activation for catalysis of a tripeptide substrate by native subtilisin and a subtilisin mutant (Asn 155----Ala 155). Our studies lead to a calculated difference in free energy of binding which is relatively small, but a calculated change in free energy of catalysis which is substantial. These energies are very close to those determined experimentally (J. A. Wells and D. A. Estell, personal communication), which were not known to us until the simulations were completed. This demonstrates the predictive power and utility of theoretical simulation methods in studies of the effects of site-specific mutagenesis on both enzyme binding and catalysis. 相似文献
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Accumulation of a heat shock-like protein during differentiation of human erythroid cell line K562 总被引:2,自引:0,他引:2
The human erythroid cell line K562 provides a model system for studying erythroid differentiation and eukaryotic gene regulation. These cells express glycophorin A, spectrin and i antigen. They accumulate embryonic and fetal haemoglobins on induction of erythroid differentiation with haemin, sodium butyrate or hydroxyurea. In the present study, the protein composition of K562 cells during haemin-mediated induction of erythroid maturation was analysed by two-dimensional gel electrophoresis. Under conditions in which haemin did not effect cell viability and proliferation, a protein of approximately 70,000 molecular weight (MW) accumulated in the differentiated K562 cells. The accumulation appears to be due to an increase in the rate of RNA synthesis for this protein. The protein is related in sequence to a 70,000-MW heat shock protein. An antigenically related protein was also demonstrated in human bone marrow and accumulates at particular stages of human erythroid maturation. 相似文献
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Summary The treatment of onion root meristems with the pesticide Sevin [carbaryl (1-naphthyl n-methyl carbamate)] induces an accumulation of interphase nuclei with a larger diameter, and a subsequent decrease in the index of smaller nuclei. It is concluded that Sevin depresses mitosis by arresting cells at G2 without affecting DNA synthesis.The authors are grateful to Prof. K. S. Bilgrami, Head of the Postgraduate Department of Botany, Bhagalpur University, for providing facilities and to Prof. B.N. Mookerjee for his valued suggestions. 相似文献
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