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101.
V. I. Kaledin S. I. Ilnitskaya E. A. Vasyunina N. A. Popova L. A. Bogdanova M. L. Perepechaeva A. Y. Grishanova 《Biophysics》2015,60(6):970-976
In this work, the biological effects of diethylnitrosamine (DENA) have been studied under controlled conditions of its metabolism in mice of different ages. The results indicate that the general toxic and hepatocarcinogenic effects of DENA are mostly due to the parent compound, whereas the alkylating metabolites cause hepatic cell damage. Our findings cast doubt on the conventional understanding of the exclusive role of mutagenic activation in the carcinogenic action of chemicals. 相似文献
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Karpova L S Popovtseva N M Stolyarova T P Stolyarov K A Mamadaliyev S M Khairullin B M Sandybayev N T Kydyrbayev Zh K Orynbayev M B Ospanov K S Baiserkin B S Boibosinov E U 《Virologica Sinica》2011,(5)
The aim of the work is the comparison of the epidemiology of influenza and acute respiratory virus infections (ARVI) in the Republic of Kazakhstan with the corresponding influenza epidemic in Russia induced by influenza pandemic virus A/California/07/2009 in 2009.Data on influenza and ARVI from the Republic of Kazakhstan and Federal Center of influenza was collected and investigated over the course of several weeks from hospitalized patients with the same diagnosis among all population and in age groups on ... 相似文献
104.
Balaban PM Malyshev AY Ierusalimsky VN Aseyev N Korshunova TA Bravarenko NI Lemak MS Roshchin M Zakharov IS Popova Y Boyle R 《PloS one》2011,6(3):e17710
Background
The mollusk statocyst is a mechanosensing organ detecting the animal''s orientation with respect to gravity. This system has clear similarities to its vertebrate counterparts: a weight-lending mass, an epithelial layer containing small supporting cells and the large sensory hair cells, and an output eliciting compensatory body reflexes to perturbations.Methodology/Principal Findings
In terrestrial gastropod snail we studied the impact of 16- (Foton M-2) and 12-day (Foton M-3) exposure to microgravity in unmanned orbital missions on: (i) the whole animal behavior (Helix lucorum L.), (ii) the statoreceptor responses to tilt in an isolated neural preparation (Helix lucorum L.), and (iii) the differential expression of the Helix pedal peptide (HPep) and the tetrapeptide FMRFamide genes in neural structures (Helix aspersa L.). Experiments were performed 13–42 hours after return to Earth. Latency of body re-orientation to sudden 90° head-down pitch was significantly reduced in postflight snails indicating an enhanced negative gravitaxis response. Statoreceptor responses to tilt in postflight snails were independent of motion direction, in contrast to a directional preference observed in control animals. Positive relation between tilt velocity and firing rate was observed in both control and postflight snails, but the response magnitude was significantly larger in postflight snails indicating an enhanced sensitivity to acceleration. A significant increase in mRNA expression of the gene encoding HPep, a peptide linked to ciliary beating, in statoreceptors was observed in postflight snails; no differential expression of the gene encoding FMRFamide, a possible neurotransmission modulator, was observed.Conclusions/Significance
Upregulation of statocyst function in snails following microgravity exposure parallels that observed in vertebrates suggesting fundamental principles underlie gravi-sensing and the organism''s ability to adapt to gravity changes. This simple animal model offers the possibility to describe general subcellular mechanisms of nervous system''s response to conditions on Earth and in space. 相似文献105.
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Dominance relations and the pituitary-adrenal system in rats 总被引:1,自引:0,他引:1
110.
Pagis L. Ya. Popova L. G. Andreev I. M. Balnokin Yu. V. 《Russian Journal of Plant Physiology》2001,48(3):281-286
Vesicular preparations of plasma membranes (PM) from the microalga Tetraselmis (Platymonas) viridisRouch were used to investigate the ion specificity of the Na+/H+antiporter and Na+-translocating ATPase, two Na+-transporting systems previously identified functionally by our studies of T. viridisPM. The Na+/H+antiporter and Na+-ATPase were shown to translocate, with similar efficiencies, Na+and Li+across the membrane, whereas other cations, such as K+, Rb+, and Cs+, were not transported by these systems. Transport of the latter cations across PM of T. viridisoccurred through the ion channels of PM, which were apparently selective for K+. 相似文献