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141.
A specific beta-agonist, isoproterenol, increased the intracellular content of cyclic AMP and decreased the radiosensitivity of Chinese hamster fibroblasts. Beta-antagonist, propranolol, blocked the manifestation of the effect of isoproterenol. Isoproterenol did not affect either the intracellular level of cyclic AMP or the radiosensitivity of B-82 cells which had no beta-adrenoreceptors. 相似文献
142.
The risk of malignancy in large congenital nevi 总被引:4,自引:0,他引:4
E N Kaplan 《Plastic and reconstructive surgery》1974,53(4):421-428
143.
N S Weiss 《American journal of human genetics》1972,24(1):65-70
144.
V. S. Oganov O. L. Vinogradova N. S. Dudov V. S. Baranov A. S. Minenkov A. V. Bakulin V. E. Novikov O. E. Kabitskaya M. V. Moskalenko A. S. Glotov O. S. Glotov D. V. Popov 《Human physiology》2008,34(2):182-190
The association of the polymorphism of the VDR, Col1a1, and CALCR genes with a form of osteoporosis frequently occurring as a consequence of intense physical exercise in athletes was studied. Biochemical parameters of bone remodeling and its neuroendocrine regulation, as well as the bone masses, of 22 amateur athletes were determined immediately before a strenuous nine-week training cycle (TC) and eight months later. The possible association of these factors with the polymorphism of the genes coding for bone tissue proteins was studied. Long-term intense physical training was found to be associated with a significant activation of bone tissue resorption accompanied by continued rapid synthesis. Nevertheless, and in spite of the strong activation of resorption caused by the TC, the athletes exhibited no osteoporosis (even eight months after the discontinuation of the TC); some of them, however, displayed an individual tendency to osteopenia. According to the results of genetic analysis, this was associated with the polymorphism of predisposition genes (genotype TT of the VDR gene and the functionally weakened s allele of the Col1a1 gene). 相似文献
145.
146.
Summary The conditions required for the production of a polylysine-coated gold (PL-G) complex, which shows optimal sensitivity for the demonstration of tissue anionic sites, expressed under different conditions of pH have been investigated. Problems encountered with this complex have been compared with those found with other methods of conjugation of polylysine to colloidal gold. The performance of a bovine serum albumin (BSA)-stabilized PL-G complex was examined against other PL-G conjugates, including complexes that are commercially available, for the detection of heterogeneous glomerular anionic site populations, expressed at pH 2.5 and pH 7.0. 相似文献
147.
A new brain protein is described which forms an insoluble complex with tubulin, with concomitant stoichiometric hydrolysis of GTP. The complex contains a maximum of one tubulin-binding protein (MW 52,500) per two tubulin dimers. The tubulin-binding protein (TBP) does not compete with colchicine, but in the presence of microtubule-associated proteins tubulin appeared less accessible to it. Proteins such as TBP might sequester tubulin and thereby function either to inhibit indiscriminate polymerization, or to promote ordered nucleation by maintaining high local concentrations. 相似文献
148.
149.
A Kh Kogan N I Losev A N Kudrin A Mieégombyn 《Biulleten' eksperimental'no? biologii i meditsiny》1984,97(3):270-272
The changes in the size of the myocardial injury area during reperfusion after the coronary occlusion-induced ischemia lasting 30 minutes are phasic in nature. Until 3.5 h the injured area increases and after 23.5 h relatively diminishes. After a more prolonged ischemia such manifestations are either unmarked or absent. Ischemia lasting from 30 min to 4 hours followed by reperfusion, as compared with ischemia of the same duration without reperfusion, normally gives rise to the formation of an area of injury, which is less or occasionally equal in size. The data obtained and reported indicate that in the area of coronary occlusion there are groups of cardiomyocytes that differ as regards the resistance to ischemia. 相似文献
150.
M Kh Ga?nutdinov S I Mirmakhmudova N M Mullagalieva Ia Kh Turakulov 《Biulleten' eksperimental'no? biologii i meditsiny》1984,97(3):293-295
Addition of a thermostable cytoplasmic fraction leads to the uncoupling of oxidative phosphorylation of the mitochondria. In hyperthyrosis such an effect manifests itself more powerfully than in the control. Addition of the thermostable cytoplasmic fraction induces electrogenic phosphate transport via the mitochondrial membrane. In hyperthyrosis, the activity of the thermostable inducer of phosphate transport in the cytoplasm increases. The functioning of the phosphate cycle may be the cause of the uncoupling of oxidative phosphorylation of the mitochondria during the disease in question. 相似文献