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1.
HindIII-O/N DNA fragments of vaccinia virus (VV) of the LIVP strain were mapped using thirteen restriction endonucleases. Nucleotide sequences of the HindIII-O fragment (1530 bp) as well as of a site of the HindIII-N genome fragment 353 bp in size were determined. Comparison of restriction maps and nucleotide sequences of VV strains (WR and LIVP) demonstrated that DNA of VV LIVP contained % deletions and 2 insertions. "Reliable" short direct repeats were localized and their possible role in formation of DNA deletions was shown. It was suggested that VV endonuclease and DNA-ligase participate in replication and repair processes. Mechanism of formation of variable sequences of viral genomes is discussed.  相似文献   
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The flavivirus NS3 protein plays an important role in the cleavage and processing of the viral polyprotein and in the synthesis of the viral RNA. NS3 recruits NS2B and NS5 proteins to form complexes possessing protease and replicase activities through protease and nucleoside triphosphatase/helicase domains. We have found that NS3 also induces apoptosis. Expression of the Langat (LGT) virus NS3 protein resulted in a cleavage of cellular DNA and reduced the viability of cells. Coexpression of NS3 with apoptotic inhibitors (CrmA and P35) and addition of caspase peptide substrates (Z-VAD-FMK and Z-IETD-FMK) to NS3-transfected cells blocked NS3-induced apoptosis. In cotransfection experiments, NS3 bound to caspase-8 and enhanced caspase-8-mediated apoptosis. NS3 and caspase-8 colocalized in the cytoplasm of transfected cells. Deletion analysis demonstrated that at least two regions of NS3 contribute to its apoptotic activities. The protease and helicase domains are each able to bind to caspase-8, while the protease domain alone induces apoptosis. The protease domain and tetrahelix region of the helicase domain are required for NS3 to augment caspase-8-mediated apoptosis. Thus, the LGT virus NS3 protein is a multifunctional protein that binds to caspase-8 and induces apoptosis.  相似文献   
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3,4-Di-O-benzyl-6-deoxy-6-diethoxyphosphinyl-1,2-O-isopropylidene-beta-D-fructofuranose (13) was prepared from the known 1,2-O-isopropylidene-6-O-tosyl-beta-D-fructofuranose in five steps. Reduction of 13 with sodium dihydrobis(2-methoxyethoxy)aluminate, followed by the action of hydrochloric acid and then hydrogen peroxide, afforded the 6-deoxy-6-hydroxyphosphinyl-D-fructopyranose derivative. This was converted into the 1,2,3,4,5-penta-O-acetyl-6-deoxy-6-methoxyphosphinyl-D-fructopyranoses, whose structure and conformation were established by 1H NMR spectroscopy.  相似文献   
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The sequence of vaccinia virus (VV) LIVP HindIII N DNA fragment has been determined to be 2215 b.p. Three open reading frames designated LN1, N1 and NO1 and coding polypeptides with the calculated molecular masses (32.5 kDa, 21.8 kDa and 47.8 kDa) were located. mRNAs selected by hybridization with the VV HindIII N were translated in rabbit reticulocyte lysate. Proteins of genes for host range and resistance to alpha-amanitin corresponding to 29 and 47 kDa were detected. Two forms of polypeptides of the ORF LN1 (32 and 29K), and anomalous electrophoresis mobility of the ORF LN1 are discussed.  相似文献   
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葡萄糖及脂肪酸是胰岛β细胞的关键代谢底物,葡萄糖刺激胰岛β细胞分泌胰岛素是维持机体血糖稳态平衡的关键。胰岛素抵抗发生时,β细胞对能量代谢底物的选择失调,加速胰岛β细胞由代偿到胰岛β细胞失代偿的进程,是肥胖胰岛素抵抗最终发展为2型糖尿病的始动因素。核转录因子FoxO1属于Fox家族成员,在胰腺内广泛表达,在β细胞的代谢,发育,增殖过程中发挥着重要的调节作用。鉴于FoxO1在维持胰岛β细胞功能中的关键作用,现着重对FoxO1在胰岛β细胞代谢灵活性受损及失代偿过程发生中的作用调节进行阐述。为其作为调控胰岛β细胞功能的关键靶点提供参考。  相似文献   
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Genealogies of men suffering from alcoholism (574) and healthy men (368) are investigated. It is revealed that persons from endogamous marriages are more frequently found among people suffering from alcoholism than among healthy persons (36.6% and 25.2%). 55% of men of exogamous origin have relatives suffering from alcoholism, 40% of men from endogamous marriages have such relatives. It is supposed that high heterozygosity decreases the risk of alcoholism.  相似文献   
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A total of 106 patients suffering from tumors and inflammatory diseases of the head and neck were investigated. CT was performed in axial and frontal projections using a method of intravenous contrast image enhancement. The purpose of CT was to reveal an abnormal lesion, to detect its initial site, spreading, to make differential diagnosis, and to evaluate therapeutic results. Some limitations of CT in differential diagnosis of small-size tumors were observed. CT can be used for differential diagnosis of tumors and inflammatory processes in the accessory nasal sinuses. CT results were important for a choice of therapeutic methods, radiation therapy design, assessment of efficacy of surgical and radiation therapy, and the detection of tumor recurrences.  相似文献   
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The recognition sequence and cleavage site for restriction endonuclease SsrI have been determined, the latter being 5'-GTT decreases AAC-3'. The enzyme was isolated from Staphylococcus saprophyticus strain and may be used in DNA investigation instead of its isoshizomer HpaI.  相似文献   
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