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471.
Alternative splicing of murine T-cell receptor beta-chain transcripts 总被引:12,自引:0,他引:12
472.
杨文泽 《西南师范大学学报(自然科学版)》1988,(4)
本文削弱了《内-外-∑群与极小非∑群》(陈重穆)一文中定理10.10A:条件而得到相同的结果,即定理 设G是有限群,p是|G|的素因子,且对|G|的任一素因子q有p(?)q-1 ),P是G的p-Sylow子群.若对于P的任一非平凡循环子群P,N_G(P)与C_G(P)都有正规p-补,则G为p-幂零群. 相似文献
473.
X-linked nephrogenic diabetes insipidus (NDI) is a rare disorder in which the kidney is insensitive to the antidiuretic hormone, vasopressin. It has been proposed that the kidney-specific V2 vasopressin receptor, a G protein-coupled receptor, is defective in this disorder as both the disease and the receptor map to Xq28. We report six unique mutations in the V2 receptor gene of five unrelated NDI patients, with one patient having two mutations. The most severely affected patient has a nonsense mutation which would terminate the protein in transmembrane domain III. Other mutations include three missense mutations, a frameshift and one small in-frame deletion. These results represent one of the first examples of recessive mutations affecting a G protein-coupled receptor. 相似文献
474.
M. Takahashi S. Saga S. Nagayoshi M. Imai Y. Tsutsui K. Kato M. Hoshino 《Cellular and molecular life sciences : CMLS》1981,37(2):189-190
Summary A highly sensitive sandwich enzyme immunoassay for the mouse mammary tumor virus (MMTV) is described. The assay can detect 3 ng/ml of MMTV. The enzyme used is ß-D-galactosidase fromEscherichia coli and the solid phase used is a piece of silicon rubber. 相似文献
475.
F. S. El-Feraly Y. M. Chan M. A. El-Sohly C. E. Turner 《Cellular and molecular life sciences : CMLS》1979,35(9):1131-1132
Summary Total synthesis of cannabispiran (1) was accomplished by a biomimetic-type cyclization of the bibenzyl2, using K3Fe(CN)6 or MoOCl4.Acknowledgment. Supported in part by the Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi. 相似文献
476.
Low voltage myocardial automaticity (LVA) was investigated by pharmacological modulations of the presynaptic and postsynaptic processes. The sensitivity of LVA both to inhibitor and stimulator of neurotransmitter release suggests its involvement in LVA genesis. Moreover, LVA is blocked by the inhibition of the cyclic AMP system, supporting the participation of the c-AMP-dependent membrane phosphorylation in calcium-mediated cardiac electrogenesis. 相似文献
477.
478.
Summary Renal glucose-6-phosphatase activity was found to be significantly elevated by fluoride administration (NaF 35 mg/kg, i.p.). The elevation of the enzyme activity was markedly suppressed by adrenalectomy.This work was supported in part by the Scientific Research Foundation (Grant 7014-267337) from the Education and Culture Ministry of Japan. 相似文献
479.
L Bueno R Garcia-Villar Y Ruckebusch 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,285(16):1463-1466
Identification of two distinct rhythms of the colonic slow waves at a mean frequency of 5 and 18 cycles/min. Evidence is provided for an origin of the faster rhythm from the mascularis mucosae. 相似文献
480.
Primary structure of Torpedo californica acetylcholinesterase deduced from its cDNA sequence 总被引:11,自引:0,他引:11
M Schumacher S Camp Y Maulet M Newton K MacPhee-Quigley S S Taylor T Friedmann P Taylor 《Nature》1986,319(6052):407-409
Acetylcholinesterase, an essential enzyme of the nervous system, rapidly terminates the action of acetylcholine released into the synapse. Acetylcholinesterase is also found (in lower abundance) in extrajunctional areas of muscle and nerve and on erythrocyte membranes. Hydrodynamic analyses of the native enzyme and characterization of its dissociated subunits have revealed multiple enzyme forms which can be divided into two classes: dimensionally asymmetric forms which are usually found within the synapse and contain a collagen-like structural subunit disulphide-linked to the catalytic subunits; and globular forms which appear to be widely distributed on the outer surface of cell membranes. Both forms have been characterized in the ray Torpedo californica and, although their catalytic behaviours seem to be identical, they differ slightly in amino-acid composition, peptide maps and reactivity with certain monoclonal antibodies. Here, we report the complete amino-acid sequence of an acetylcholinesterase inferred from the sequence of a complementary DNA clone. The 575-residue protein shows significant homology with the C-terminal portion of thyroglobulin. 相似文献