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1.
According to modern concepts, a malignant tumor is a complex dynamic system possessing numerous links with both the immediate environment and remote non-malignant tissues and organs. Changes in their redox balance can result in disruption of the normal tissue control. The aim of our study was to compare activity of enzymes influencing the redox state in the tumor tissue, peritumoral area, and nonmalignant tissues (taken by resection line) at various histological tumor variants. We found similar close level of reduced glutathione in the tissues of gastric adenocarcinoma and vulvar squamous cell carcinoma; however, dynamics of this parameter in the tumor surrounding tissues was different. In contrast to gastric adenocarcinoma, vulvar squamous cell carcinoma was characterized by a significant increase in glutathione content in the tumor tissue and increased activity of all investigated enzymes of the glutathione system in the tumor tissue and its peritumoral area as compared with the surrounding non-malignant tissue. These results underlie existence of clear differences in the functioning of the redox regulatory systems in the tumor and surrounding tissues of various histological origin and localization; these differences may be possibly attributed to different mechanisms involved in maintenance of the redox balance in the originally non-malignant tissues.  相似文献   
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Tick-borne encephalitis virus (TBEV) is transmitted to vertebrates by taiga or forest ticks through bites, inducing disease of variable severity. The reasons underlying these differences in the severity of the disease are unknown. In order to identify genetic factors affecting the pathogenicity of virus strains, we have sequenced and compared the complete genomes of 34 Far-Eastern subtype (FE) TBEV strains isolated from patients with different disease severity (Primorye, the Russian Far East). We analyzed the complete genomes of 11 human pathogenic strains isolated from the brains of dead patients with the encephalitic form of the disease (Efd), 4 strains from the blood of patients with the febrile form of TBE (Ffd), and 19 strains from patients with the subclinical form of TBE (Sfd). On the phylogenetic tree, pathogenic Efd strains formed two clusters containing the prototype strains, Senzhang and Sofjin, respectively. Sfd strains formed a third separate cluster, including the Oshima strain. The strains that caused the febrile form of the disease did not form a separate cluster. In the viral proteins, we found 198 positions with at least one amino acid residue substitution, of which only 17 amino acid residue substitutions were correlated with the variable pathogenicity of these strains in humans and they authentically differed between the groups. We considered the role of each amino acid substitution and assumed that the deletion of 111 amino acids in the capsid protein in combination with the amino acid substitutions R16K and S45F in the NS3 protease may affect the budding process of viral particles. These changes may be the major reason for the diminished pathogenicity of TBEV strains. We recommend Sfd strains for testing as attenuation vaccine candidates.  相似文献   
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The genetic diversity of common wheat hybrid lines Triticum aestivum/Triticum durum and Triticum aestivum/Triticum dicoccum (2n = 42, F6–7) using chromosome-specific microsatellite (SSR) markers and C-banding of chromosomes was studied. Cluster analysis of data obtained by 42 SSR markers indicated that the hybrid lines can be broken into three groups according to their origin. There were two cases of complete genetic similarity between lines 1832-2/1841-6 and 208-3/213-1, which were obtained using common wheat as the parental plants. In cross combinations, when the stabilization of the nuclear genome of hexaploid lines occurred against a background of the cytoplasmic genome of tetraploid wheats, there was a high level of divergence between sister lines, in some cases exceeding 50%. The evaluation of the degree of susceptibility of the lines to powdery mildew, leaf and stem rust, and septoria leaf blotch was performed under different environmental conditions. It was shown that resistance to powdery mildew and leaf rust significantly depended on the region where assays were conducted. An evaluation of the field data showed that the lines 195-3, 196-1, and 221-1 with T. durum genetic material displayed complex resistance to fungal pathogens in Western Siberia and the Republic of Belarus. For lines 195-3 and 196-1, one shows a possible contribution of chromosomes 4B and 5B in the formation of complex resistance to diseases. Hybrid lines with complex resistance can be used to expand the genetic diversity of modern common wheat cultivars for genes of immunity.  相似文献   
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Molecular Biology - The factors that affect the labeling of NIH 3T3 murine fibroblasts with Fe3O4-based magnetic nanoparticles (MNPs) were studied using MNPs produced by the gas condensation and...  相似文献   
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This paper discusses the relationships of zonal vegetation boundaries with some climatic indicators. Possible changes in subzonal vegetation boundaries in the territory of European Russia and Western Siberia are forecasted within the framework of one of the global warming scenarios. The revealed regularities make it possible to suggest a mathematical cartographic model of vegetation zonality for the 2046–2065 period.  相似文献   
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The effect on ozone-induced oxidation on the self-assembly of fibrin in the presence of fibrin-stabilizing factor FXIIIa of soluble cross-linked fibrin oligomers was studied in a medium containing moderate urea concentrations. It is established that fibrin oligomers were formed by the protofibrils cross-linked through γ-γ dimers and the fibrils additionally cross-linked by through α-polymers. The oxidation promoted both the accumulation of greater amounts of γ-γ dimers and the formation of protofibrils, fibrils, and their dissociation products emerging with increasing urea concentrations, which have a high molecular weight. It is concluded that the oxidation enhances the axial interactions between D-regions of fibrin molecules.  相似文献   
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Rates of psychopathology are elevated in marginalized and unstably housed persons, underscoring the need for applicable clinical measures for these populations. The Positive and Negative Syndrome Scale (PANSS) is a clinical instrument principally developed for use in schizophrenia to identify the presence and severity of psychopathology symptoms. The current study investigates whether a reliable and valid PANSS factor structure emerges in a marginally housed, heterogeneous sample recruited from the Downtown Eastside of Vancouver where substance use disorders and psychiatric illness are pervasive. Participants (n = 270) underwent structured clinical assessments including the PANSS and then were randomly assigned to either exploratory (EFA) or confirmatory factor analytic (CFA) subsamples. EFA pointed to a novel three factor PANSS. This solution was supported by CFA. All retained items (28 out of 30) load significantly upon hypothesized factors and model goodness of fit analyses are in the acceptable to good range. Each of the three first-order factor constructs, labeled Psychosis/Disorganized, Negative Symptoms/Hostility, and Insight/Awareness, contributed significantly to measurement of a higher-order psychopathology construct. Further, the latent structure of this 3-factor solution appears temporally consistent over one-year. This PANSS factor structure appears valid and reliable for use in persons with multimorbidity, including substance use disorders. The structure is somewhat distinct from existing solutions likely due to the unique characteristics of this marginally housed sample.  相似文献   
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