排序方式: 共有74条查询结果,搜索用时 78 毫秒
1.
2.
Tatiana Y Prudnikova Liudmila A Mostovich Natalia V Domanitskaya Tatiana V Pavlova Vladimir I Kashuba Eugene R Zabarovsky Elvira V Grigorieva 《Cancer cell international》2010,10(1):27
Background
D-glucuronyl C5-epimerase (GLCE) is one of the key enzymes in the biosynthesis of heparansulfate proteoglycans. Down-regulation of GLCE expression in human breast tumours suggests a possible involvement of the gene in carcinogenesis. In this study, an effect of GLCE ectopic expression on cell proliferation and viability of breast carcinoma cells MCF7 in vitro and its potential molecular mechanisms were investigated. 相似文献3.
We consider the active shell as a single-cell or epithelial sheet surface that, sharing basic properties of stretched elastic shells, is capable of active planar movement owing to recruiting of the new surface elements. As model examples of their morphogenesis, we consider the growth and differentiation of single-cell hairs (trichomes) in plants of the genus Draba, and the epiboly and formation of the dorsoventral polarity in loach. The essential feature of the active shell behavior at both cellular and supracellular levels is regular deviating from the spatially homogeneous form, which is a primary cause of originating of the active mechanical stresses inside the shell in addition to its passive stretching by the intrinsic forces. Analyzing the quantitative morphological data, we derive the equations in which the temporal self-oscillations and spatial differentiation are distinguishable only at the parametric level depending on the proportion of active to passive stresses. In contrast to the ordinary activator-inhibitor systems, the self-oscillation dynamics is principally non-local and, consequently, one-parametric, the shell surface curvature being an analog of the inhibitor, while its spatial variance being an analog of the activator of shaping. Analyzing variability and evolution of the hair cell branching, we argue that the linear ontogeny (succession of the developmental stages) is a secondary evolutionary phenomenon originating from cyclic self-organizing algorithms of the active shell shaping. 相似文献
4.
O. I. Kiselev V. M. Blinov M. M. Pisareva V. A. Ternovoy A. P. Agafonov D. V. Saraev M. Ju. Eropkin T. G. Lobova V. A. Grigorieva M. P. Grudinin 《Molecular Biology》2008,42(1):70-78
In the second half of 2005, a large-scale outbreak of influenza in poultry and wild birds was caused by a highly pathogenic H5N1 influenza virus in Russia. The level of pathogenicity is a polygenic trait, and most individual genes contribute to the influenza A virus pathogenicity in birds, animals, and humans. The full-length nucleotide sequences were determined for H5N1 strains isolated in the Kurgan region (Western Siberia). The structure of viral proteins was analyzed using the deduced amino acid sequences. The receptor-binding site of hemagglutinin (HA) in strains A/chicken/Kurgan/05/2005 and A/duck/Kurgan/08/2005 was typical for avian influenza viruses and contained Glu and Gly at positions 226 and 228, respectively. The structure of the basic amino acid cluster located within the HA cleavage site was identical in all isolates: QGERRRKKR. According to the neuraminidase structure, all H5N1 isolates from the Kurgan region were assigned to the Z genotype. Amino acid residues typical for the avian influenza virus were revealed in 30 out of 32 positions of M1, M2, NP, PA, and PB2, determining the host range specificity. One of the strains contained Lys at position 627 of PB2. Isolates from the Kurgan region were shown to have a remantadine-sensitive genotype. Both strains contained Glu at position 92 of NS1, indicating that the virus is interferon-resistant. Phylogenetic analysis related the Kurgan isolates to subclade 2 of clade 2 of highly pathogenic H5N1 influenza viruses. 相似文献
5.
6.
L. A. Lyapina T. Yu. Obergan M. E. Grigorieva E. S. Maistrenko 《Moscow University Biological Sciences Bulletin》2013,68(3):91-94
In the present work, the formation of the proline-heparin complex has been established. The way to synthesize the complex in vitro has been developed. The complex synthesized with the molar ratio of proline to heparin of 3: 1 extended the time of formation of a fibrin clot, reduced platelet aggregation, and showed a lytic effect towards nonstabilized fibrin in vitro conditions. Ten minutes after intravenous administration of the proline-heparin complex, there was an increase in levels of fibrin-depolymerization, anticoagulant, antifibrin-stabilizing and antiplatelet activity in blood of animals, whereas its components, proline and heparin, did not have such effects. 相似文献
7.
M. Schletterer L. Füreder V. V. Kuzovlev Y. N. Zhenikov I. L. Grigorieva 《Hydrobiologia》2014,729(1):175-189
The Volga, the largest river in Europe, has experienced multiple stressors from human activities. Recently we showed that its upper course (about 500 km, from its source to Tver) still has large sections with low impact and a natural type-specific potamal flora and fauna. Our present research in the East European lowlands aim to define reference conditions for mid-sized to large lowland rivers in order to build a basis for future management and conservation. Three monitoring sites were selected based on the results from intensive sampling in 2005. In subsequent field campaigns between 2006 and 2010 regular surveys were carried out each year in summer and additional ones in spring. A taxon-rich macroinvertebrate fauna, including several rare potamal relict species, was recorded and the data was used to provide an overview of annual and interannual variation in community indices and metrics. The conditions described for the headwaters of the Volga River system can be used as a reference state for medium-sized and large lowland rivers in regions where reference sites of these types are lacking. 相似文献
8.
9.
10.
Travel to distant places where the climate is different to that at home involves a period of short-term acclimatization adjustment
following arrival during which the traveler might experience thermally-induced physiological strain. This may be expressed
as an “acclimatization thermal loading” (ATL). The first signs of this show up in the respiratory organs. In the current study,
the Acclimatization Thermal Strain Index (ATSI) is developed and used for assessment of ATL for recreational travel over a
range of climatic conditions. ATSI estimates the impact of short-term acclimatization calculated as the ratio of a difference
between respiratory heat losses at the traveler’s home location to respiratory heat losses at the trip destination upon first
arriving there. The Russian Far East region is used as a case study. The research focuses on the effects of travel from two
locations in the study region. The results show that ATSI values can be significantly different when considering places of
trip origin. For example, travel from Anadyr to other locations within the Russian Far East could lead to large ATSI in summer.
In contrast, ATSI values are small for travel almost anywhere in the region during winter, but this is against a backdrop
of extreme cold for the region as a whole. Here, the diversity of climatic conditions of both heat and cold means short-term
adjustment to conditions could be stressful or worse for those who travel to participate in outdoor activities. 相似文献