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511.
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
512.
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
513.
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
514.
515.
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
516.
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
517.
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
518.
Antibodies to paired helical filaments in Alzheimer's disease do not recognize normal brain proteins 总被引:8,自引:0,他引:8
During ageing of the human brain, and particularly in senile dementia of the Alzheimer type (AD), many neurones progressively accumulate abnormal cytoplasmic fibres, called paired helical filaments (PHF). Each such fibre consists of a pair of intermediate (10 nm) filaments twisted into a double helix with a periodicity of 160 nm. PHF accumulate in large perikaryal masses, called neurofibrillary tangles, and are also found in degenerating cortical neurites that form neurite plaques. The density of PHF-containing neurites and cell bodies correlates with the degree of dementia and the extent of loss of cholinergic neurotransmitter function in AD. Recently, we demonstrated that PHF from human cerebral cortex are large, rigid polymers with unusual molecular properties, including insolubility in SDS, urea and other denaturing solvents and apparent resistance to protease digestion. These properties have so far prevented complete purification and analysis of the constituents of PHF. Based on their insolubility, we have developed a new method of preparing highly enriched PHF fractions and have raised an antiserum that is highly specific for PHF. We report here that this antiserum specifically labels PHF, free of any associated normal fibrous proteins and, unexpectedly, it reacts with neither neurofilaments nor any other normal cytoskeletal protein in brain sections or on immunoblotted gels. These anti-PHF antibodies have been used for the specific detection of Alzheimer-type PHF and in the search for cross-reacting antigens in various tissues, and are suitable for immunoaffinity purification of PHF. Our results indicate that PHF contain determinants that are not shared with normal neuronal fibrous proteins. 相似文献
519.
Y. Arlot-Bonnemains A. Van-Wormhoudt P. Favrel M. Fouchereau-Péron G. Milhaud M. S. Moukhtar 《Cellular and molecular life sciences : CMLS》1986,42(4):419-420
Summary A molecule immunologically related to salmon calcitonin has been detected in the hemolymph of the shrimpPalaemon serratus. Its concentration varies inversely with the calcium level during the molt cycle; a maximum (14 ng/ml) is found in the post-molt stage and a minimum (0.5 ng/ml) during the premolt stage. 相似文献
520.
High level radioactive nuclides in Japan in May 总被引:1,自引:0,他引:1