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Chernukha MIu Alekseeva GV Shaginian IA Romanova IuM Stepanova TV Batov AB Gintsburg AL 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2005,(6):46-51
The results of the study of hospital strains of the B. cepacia complex, isolated in hospitals of Moscow, with the use of phenotypical and molecular-genetic methods are presented. The phenotypical methods made it possible to differentiate Russian strains and classify them with a group of genomovars (I, III, IV). As the result the epidemic importance of the strains with epidemic markers, having specific characteristics for every clinic, was determined. The detection of the collection of genes cepI and cepR in the strains made confirmed the epidemic importance of the stains which had, due to the regulatory "quorum sensing" (QS) system, the potential capacity for inducing infection and persisting in the patient's body. The presence of gene cepR in all strains and the absence of gene cepl in 33% of strains gave evidence to suggest that in some strains the activation of the production of pathogenicity factors required the presence of other bacteria having the fully developed QS system. Thus, the new complex approach with the use of phenotypical and molecular-genetic methods permits more precise identification of the source of hospital infection induced by the bacteria of the B. cepacia complex. 相似文献
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研究抗肿瘤药阿霉素对Wnt通路抑制因子FrpHE(frizzled-related protein)和DKK-1(Dickkopf-1)表达的作用.将抗肿瘤药阿霉素加入到人肝癌HepG2(HepG2,含野生型p53;Hep3B,p53缺失)、人大肠癌(Lovo,含野生型p53)和人神经胶质瘤细胞(U251,p53突变)细胞株中.以RT-PCR技术检测阿霉素对Wnt通路抑制因子FrpHE和DKK-1的表达调节作用,以流式细胞术检测在肿瘤细胞中Wnt通路的关键调节因子β-catenin的表达.在加入阿霉素24h后FrpHEmRNA表达水平在人肝癌细胞(HepG2,含野生型p53;Hep3B,p53缺失)中与对照组相比表达水平显著增加.在人大肠癌细胞(Lovo,含野生型p53)和人神经胶质瘤细胞(U251,p53突变型)细胞中,未见FrpHE mRNA表达.DKK-1mRNA表达水平在人肝癌细胞(HepG2,含野生型p53;Hep3B,p53缺失)、人大肠癌细胞(Lovo,含野生型p53)和人神经胶质瘤细胞(U251,p53突变型)中与对照组相比表达水平显著增加.β-catenin的阳性细胞百分比强度和平均荧光量强度与对照组相比,表达水平降低.提示化疗药阿霉素能明显诱导抑制剂FrpHEmRNA和DKK-1mRNA的表达. 相似文献
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A. R. Kotovskaya M. I. Koloteva V. Yu. Luk’yanuk G. P. Stepanova L. M. Filatova S. P. Builov A. F. Zhernavkov L. L. Kondratuk 《Human physiology》2010,36(7):871-876
Analysis of alterations in the cardiac activity on the basis of electrocardiographic (ECG) findings in 29 cosmonauts of flight
and ground professions aged from 29 to 61 years after 34 short (8–30 days) space flights (SFs) between 1982 and 2006 has been
carried out. The ECG data at the stage of clinical selection, clinical-physiological examination (CPE) before a SF, at the
stage of the launch of a spacecraft (SC) into orbit and its landing on Earth and at the stage of postflight CPE have been
analyzed. The analysis of cardiac activity parameters on the basis of ECG data at different stages of observations has led
to the identification of three groups of cosmonauts. There were no significant changes or negative tendencies in the alteration
of ECG data in the first group (55.2% of the total number of cosmonauts) during the observation period from selection to the
end of the SF. The changes that later became more pronounced during the landing on Earth and were retained during postflight
CPE have been found in the second group of cosmonauts (in 34.5% cases) at the time of selection and preflight CPE. Considerable
disturbances in cardiac activity that are dangerous for human health have been found in ECGs in the third group (10.3%) during
the descent from orbit. The data from the study are the first step in the investigation of possible medical risks for the
development and improvement of requirements for the medical selection of crews and the admission of subjects with partial
health insufficiency on SFs. 相似文献
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The electron-microscopic examinations of lymphocytes and neutrophiles in circulating blood of children irradiated during intrauterine development and on posterior stages of ontogenesis were performed in dynamics after accidental period. Some changes in lymphocyte ultrastructure were revealed; namely the increased undulation of nuclear contours with dilated perinuclear space and some reconstructions of their cellular organoids (the increased density of mitochondrial matrix, crist disorganization, dilation of clear space in cisterns of cytoplasmic net, disorders in the structure of electron-dense granules). The peculiarities of neutrophile ultrastructure that are characterized by centre dilated perinuclear space, decrease in glycosomes, disorders in granular structure, vacuole presence, degradation of cytoplasm and nuclear hypersegmentation were determined. 相似文献
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