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111.
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113.
H. Singh K. K. Bhutani R. K. Malhotra D. Paul 《Cellular and molecular life sciences : CMLS》1978,34(5):557-558
Summary The tetrazole analogues of progesterone and testosterone, namely, 7a-aza-B-homo-4-pregneno[7a, 7-d]tetrazole-3,20-dione (5) and 3-oxo-7a-aza-B-homo-4-androsteno[7a, 7-d]tetrazol-17-yl acetate (8), have been prepared which are worthy of biological testing.Part XLIII in the series Steroids and Related Studies. For Part XLII see H. Singh and K.K. Bhutani, Indian J. Chem. in press. 相似文献
114.
Y. Singh V. K. Chaudhary S. R. Tyagi R. Bhatnagar U. K. Misra 《Cellular and molecular life sciences : CMLS》1988,44(9):758-759
Summary Rats fed on a rice diet deficient in lysine and threonine showed increased activities of CDP-Choline pathway enzymes and incorporation of (methyl-3H)-choline into hepatic microsomal phosphatidylcholine, compared to rats fed on the same diet supplemented with lysine and threonine. However, the amount of microsomal phosphatidylcholine was significantly decreased in rats fed a deficient rice diet. These results suggest an enhanced phosphatidylcholine catabolism in rats fed on a rice diet deficient in lysine and threonine. Malathion administration reduced the amount of phosphatidylcholine in all the groups. 相似文献
115.
Isolation and structure of the strong cell growth and tubulin inhibitor combretastatin A-4 总被引:7,自引:0,他引:7
The African tree Combretum caffrum (Combretacae) has been found to contain a powerful inhibitor of tubulin polymerization (IC50 2-3 microM), the growth of murine lymphocytic leukemia (L 1210 and P 388 with ED50 approximately 0.003 microM and human colon cancer cell lines [(e.g. LoVo (ED50 = 0.005 microgram/ml), HT 29 (ED50 0.02 microgram/ml, Colo 205 (ED50 = 0.07 microgram/ml), DLD-1 (ED50 = 0.005 microgram/ml) and HCT-15 (ED50 = 0.0009 microgram/ml] designated combretastatin A-4 (1c). The structure assigned by spectral techniques was confirmed by synthesis. 相似文献
116.
During Acanthocheilonema viteae infection, the specific activity of gamma-glutamyltranspeptidase (gamma-GT) increased in peritoneal exudate cells and bone marrow and decreased in lymph nodes of Mastomys natalensis throughout the course of infection. However, though there was an increase in specific activity of gamma-GT in thymus and spleen during the prepatent phase of A. viteae infection, the level either returned to normal or decreased during the latent phase of infection. A close correlation was observed between the host's immune status during A. viteae infection and the level of gamma-GT in lymphoid tissues. 相似文献
117.
Summary Acetylcholinesterase (AChE) activity was studied in the glycogen bodies of the spinal cords of 2 birds namelyStreptopelia senegalensis andPasser domesticus. A possible functional significance of AChE in the light of relative enzymatic localization especially in Hoffmann-Kolliker
nuclei (motor cell groups), substantia gelatinosa and other regions of gray matter of 2 avian glycogen bodies has been discussed. 相似文献
118.
Identification of a host protein essential for assembly of immature HIV-1 capsids. 总被引:18,自引:0,他引:18
Concepcion Zimmerman Kevin C Klein Patti K Kiser Aalok R Singh Bonnie L Firestein Shannyn C Riba Jaisri R Lingappa 《Nature》2002,415(6867):88-92
To form an immature HIV-1 capsid, 1,500 HIV-1 Gag (p55) polypeptides must assemble properly along the host cell plasma membrane. Insect cells and many higher eukaryotic cell types support efficient capsid assembly, but yeast and murine cells do not, indicating that host machinery is required for immature HIV-1 capsid formation. Additionally, in a cell-free system that reconstitutes HIV-1 capsid formation, post-translational assembly events require ATP and a subcellular fraction, suggesting a requirement for a cellular ATP-binding protein. Here we identify such a protein (HP68), described previously as an RNase L inhibitor, and demonstrate that it associates post-translationally with HIV-1 Gag in a cell-free system and human T cells infected with HIV-1. Using a dominant negative mutant of HP68 in mammalian cells and depletion-reconstitution experiments in the cell-free system, we demonstrate that HP68 is essential for post-translational events in immature HIV-1 capsid assembly. Furthermore, in cells the HP68-Gag complex is associated with HIV-1 Vif, which is involved in virion morphogenesis and infectivity. These findings support a critical role for HP68 in post-translational events of HIV-1 assembly and reveal a previously unappreciated dimension of host-viral interaction. 相似文献
119.
R. N. Pal R. C. Batra S. K. Munshi N. K. Mehrotra Raghbir Singh 《Cellular and molecular life sciences : CMLS》1973,29(1):34-36
Zusammenfassung Der Gehalt an freien Aminosäuren von auf Rizinus-, Zizyphus- und Holzapfelblättern ernährten Larven und deren Puppen vonEuproctis fraterna wurde vergleichend untersucht. Zwischen den beiden Stadien werden massgebende Unterschiede festgestellt. Während die Gesamtmenge der Aminosäuren im Larven- und Puppenstadium der mit Rizinus ernährten Insekten ähnlich war, wurden in den Puppen anders ernährter Tiere bedeutend mehr Aminosäuren beobachtet als in Larven. -Aminobuttersäure kam nur im Larvenstadium vor. 相似文献
120.