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排序方式: 共有6951条查询结果,搜索用时 15 毫秒
951.
Zusammenfassung Die Hitzesensibilisierung von Weizenwurzelmeristemen kann durch Kältebehandlung oder Kinetinzugaben zumindest teilweise rÜckgängig gemacht werden. 相似文献
952.
953.
Cell and organotypical cultures are used to study the direct effect of serotonin and of ketanserin, a serotonin antagonist, on dermal and epidermal cells of embryonic chick skin. Ketanserin stimulates the increase in cell number and inhibits the differentiation, whereas serotonin stimulates differentiation and inhibits the increase in cell number. 相似文献
954.
955.
Novel mutations in families with unusual and variable disorders of the skeletal muscle sodium channel. 总被引:11,自引:0,他引:11
A I McClatchey D McKenna-Yasek D Cros H G Worthen R W Kuncl S M DeSilva D R Cornblath J F Gusella R H Brown 《Nature genetics》1992,2(2):148-152
Mutations in the skeletal muscle sodium channel gene (SCN4A) have been described in paramyotonia congenita (PMC) and hyperkalaemic periodic paralysis (HPP). We have found two mutations in SCN4A which affect regions of the sodium channel not previously associated with a disease phenotype. Furthermore, affected family members display an unusual mixture of clinical features reminiscent of PMC, HPP and of a third disorder, myotonia congenita (MC). The highly variable individual expression of these symptoms, including in some cases apparent non-penetrance, implies the existence of modifying factors. Mutations in SCN4A can produce a broad range of phenotypes in muscle diseases characterized by episodic abnormalities of membrane excitability. 相似文献
956.
957.
The mechanics of chromosome movement, mitotic spindle assembly and spindle elongation have long been central questions of cell biology. After attachment in prometaphase of a microtubule from one pole, duplicated chromosome pairs travel towards the pole in a rapid but discontinuous motion. This is followed by a slower congression towards the midplate as the chromosome pair orients with each kinetochore attached to the microtubules from the nearest pole. The pairs disjoin at anaphase and translocate to opposite poles and the interpolar distance increases. Here we identify CENP-E as a kinesin-like motor protein (M(r) 312,000) that accumulates in the G2 phase of the cell cycle. CENP-E associates with kinetochores during congression, relocates to the spindle midzone at anaphase, and is quantitatively discarded at the end of the cell division. CENP-E is likely to be one of the motors responsible for mammalian chromosome movement and/or spindle elongation. 相似文献
958.
The administration of ox-spleen homogenate, whether in rats made polycythemic by blood transfusion or in mice polycythemic by hypoxia, elicited a significant stimulatory effect on the rate of erythropoiesis. This activity remained unchanged even if the spleen, before being homogenized, was exhaustively washed with isotonic buffer pH 7.4 up to the total blood elimination. 相似文献
959.
A. J. Baars M. Jansen S. Arnoldussen K. L. de Lussanet de la Sablonière D. D. Breimer 《Cellular and molecular life sciences : CMLS》1982,38(4):426-427
Summary The enzymatically catalyzed conjugation of glutathione with 1-chloro-2,4-dinitrobenzene and styrene-7,8-oxide is inhibited by tetrabromosulfophthalein in a non-competetive way, although tetrabromosulfophthalein itself is a substrate for glutathione S-transferases. Dibromosulfophthalein, which is not a substrate for glutathione S-transferases, inhibits the 1-chloro-2,4-dinitrobenzene conjugation competetively and the styrene-7,8-oxide conjugation non-competetively. 相似文献
960.
Epimastigotes of Trypanosoma cruzi (Tulahuen strain Tul 0 stock) biotransform benznidazole (N-benzyl-2-nitro-1-imidazole acetamide) to reactive metabolites that bind covalently to DNA, proteins and lipids of the parasite. These effects might be related to the trypanocidal action of benznidazole, a chemotherapeutic agent against Chagas' disease. 相似文献