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301.
302.
V S Tikhonchuk V V Antipov B I Davydov A A Galkin 《Biulleten' eksperimental'no? biologii i meditsiny》1979,88(7):55-57
In the experiments on 2200 mice the thresholds of powder density (PD) and time of irradiation were defined, when the death level did not exceed 0.1%. Dependence between the speed ratio of the destruction/regeneration and PD approached the exponential function. The functional dependences obtained quantitatively characterize the adaptive abilities of the mouse organism exposed to microwave irradiation. 相似文献
303.
304.
The comparison of the reduction kinetics of cytochrome c and nitroxide radical by ascorbate in reversed micelles of aerosol OT in octane was studied. The plot of the dependence of the reduction rate constant on the micelle hydratation is bell-shaped in the case of protein but shows the plateau form for the radical. The reaction rates decreases at high micelle concentrations. The equations have been drawn that connect the experimental rate constants with intramicellar biomolecular rate constant (km) for reagents unsolved in organic phase. In the case of strong hydratated micelles km for the radical reduction is practically equal to the rate constant in aqueous solution. For cytochrome c the ratio of these constants is less than 0.22, that may be explained by protein conformational changes detected by optical methods. For small micelle hydratation the dependence of the cytochrome reduction rate on ascorbate concentration is characterized by plateau. Under these conditions the limited stage of reaction is apparently the transition of the protein to the active conformation. 相似文献
305.
Sery Gonedelé Bi Didier P Sokouri Kouakou Tiékoura Oulo Alla N?Nan Marcel Lolo Félix Gnangbé Assanvo SP N?Guetta 《Bioinformation》2014,10(11):671-678
Cête d׳Ivoire continues to have the highest HIV-1 prevalence rate in West Africa, although the infection number is in constant
decline. The external envelope protein of the viruses is a likely site of selection, and responsible for receptor binding and entry into
host cells, and therefore constitutes an ideal region with which to investigate the evolutionary processes acting on HIV-1. In this
study, we analyse 189 envelope glycoprotein V3 loop region sequences of viruse isolates from 1995 to 2009, from HIV-1 untreated
patients living in Cête d׳Ivoire, to decipher the temporal relationship between disease diversity, divergence and selection. Our
analyses show that the nonsynonymous and synonymous ratio (dN/dS) was lower than 1 for viral populations analysed within 15
years, which showed the sequences did not undergo adequate immune pressure. The phylogenetic tree of the sequences analysed
demonstrated distinctly long internal branches and short external branches, suggesting that only a small number of viruses
infected the new host cell at each transmission. In addition to identifying sites under purifying selection, we also identified neutral
sites that can cause false positive inference of selection. These sites presented form a resource for future studies of selection
pressures acting on HIV-1 enν gene in Cête d׳Ivoire and other West African countries. 相似文献
306.
Gleb S. Budylin Denis A. Davydov Nadezhda V. Zlobina Alexey V. Baev Vyacheslav G. Artyushenko Boris P. Yakimov Evgeny A. Shirshin 《Journal of biophotonics》2022,15(1):e202100268
Quantitative noninvasive assessment of water content in tissues is important for biomedicine. Optical spectroscopy is potentially capable of solving this problem; however, its applicability for clinical diagnostics remains questionable. The presented study compares diffuse reflectance spectroscopy, Raman spectroscopy and multispectral imaging in the characterization of cutaneous edema. The source-detector geometries for each method are selected based on Monte Carlo simulations results to detect the signal from the dermis. Then, the kinetics of the edema development is studied for two models. All methods demonstrate synchronous trends for histamine-induced edema: The water content reaches a maximum of 1 hour after histamine application and then gradually decreases. For the venous occlusion, a 51% increase in water content is observed with Raman spectroscopy. The differences in water content estimation by three methods are explained based on the light propagation model. The obtained results are essential for introducing quantitative optical water measurement technology to the clinics. 相似文献
307.
The study of catalase myocardium activity at stress in adult and old rats has been performed. It has been revealed that the formation of immobilization stress is accompanied by the enzyme activity stimulation. The expression of this effects is more significant in adult animals. Experimental data concerning the possible role of peroxidation lipids in myocardium catalase stress activation and its age modulation are given. 相似文献
308.
309.
The influence of music of a specified intensity on the latency of recognition of even and odd numbers with the involvement
of the left and the right hands, respectively, has been studied. Musical accompaniment decreases the latency of recognition
to a greater extent if the left hand is involved. Apparently, this is related to the activating influence of music on the
right hemisphere in persons who are not professional musicians. The increase in the efficiency of recognition caused by musical
accompaniment is considered to be an expression of the dominant principle. 相似文献
310.
Malonic acid injection causes an increase in the survival of rats with acute hypoxic hypoxia. Endogenic malonic acid is supposed to be of great importance in stimulating tissue resistance to hypoxia. 相似文献