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21.
It is shown that oxipine (mexidol; a 3-hydroxypyridine-derived antioxidant) injected intravenously into rabbits in a dose of 10 or 25 mg/kg alleviates the severity of the anaphylactic reaction, lowers the anaphylactic index, and considerably reduces the percentage of anaphylaxic shock-induced mortality. The preparation causes changes in the ratio of the total lipid to phospholipid fractions of lymphocytes, which has distinctive features in intact, primed, and challenged animals. It is thought that the antiallergic effects of oxipine are connected with both inhibition of free-radical oxidation and with the ability of the preparation to alter receptor properties of the allergy target cells due to its effect on the lipid ensembles of the cell membranes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, No 4, pp. 384–386, April, 1995 Presented by P. V. Sergeev, Member of the Russian Academy of Medical Sciences  相似文献   
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The karyotype of meadow fescueFestuca pratensis Huds. (2n=14) has been studied by means of fluorescence banding techniques. At-enriched heterochromatic bands were revealed in the metaphase chromosomes 1–6. A single GC-rich band was associated with the chromosome 2 secondary constriction. Delay of condensation of the heterochromatic regions was discovered. The heterochromatic bands reported are markers which allow identification of all meadow fescue chromosomes.  相似文献   
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Nonstructural protein 3 (NS3) of human hepatitis C virus (HCV) is a conserved multi-functional protein essential for replication and translation of viral RNA and polyprotein processing. Early T-cell response against NS3 is capable of restricting viremia. We aimed at characterizing the immunogenicity in gene immunization of the conserved regions of NS3 critical for protein folding and activity. C57BL/6 mice were injected with NS3 gene of Russian HCV 1b isolate 274933RU. Immunization did not exert any overt histological changes and had no long-term effects on the immune status of NS3 gene-recipients. The immune response in NS3 gene-recipients was screened by antibody ELISA, T-cell proliferation test and immune assays for specific cytokine production. T-lymphocytes of NS3 gene-recipients proliferated in response to peptides representing conserved regions of protease and ATPase/helicase. Stimulated T-lymphocytes produced IL-2, and in response to protease-derived peptides, also IFN-gamma. Potent and long-lasting antibody response was raised against conserved NS3 regions including "Greek-key" motif of protease, motifs II, V and polynucleotide-binding domains of ATPase/helicase. Thus, gene immunization effectively targeted conserved regions critical for NS3 protease and helicase function. In type and specificity, immune response of NS3 gene-immunized mice mimicked immunity achieved in the acute self-limiting HCV infection of human and primates and in virus-exposed healthy individuals, indicating promiscuity of NS3 as immunogen.  相似文献   
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俄罗斯不同气候地区不同功能水体中克雷伯菌属广泛分布。克雷伯菌属可见于遭受生物、化学污染的集中供水的地表水源,无防护的地下蓄水层,缺乏有效清洁、消毒系统的饮用水。研究表明,水体中的克雷伯菌属具有致病性和毒性,对现代药物和消毒剂(氯、紫外线)具有抗性,很容易穿透进入地下蓄水层。克雷伯菌属细菌有很强的致病性(粘附力、侵袭力、磷酸酯酶、卵磷脂酶、脱氧核糖核酸酶、溶血活性),含有致病性遗传标记cnf-1。克雷伯菌属(100 CFU/dm3)可引起急性肠道感染。在不检测总大肠菌群的情况下,检测水体尤其是饮用水中的克雷伯菌属,可以评估所用水的流行病学危险。  相似文献   
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V M Smirnov 《Kardiologiia》1983,23(10):96-98
Mechanisms of cardiac acceleration in response to vagal stimulation under some experimental conditions were investigated. The stimulation of one (left or right) or both vagal nerves in pigeons was not shown to produce the acceleration phenomenon either in the presence of atropine effects and stimuli of varying intensity, or with weak and sparse stimulation of intact pigeons.  相似文献   
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Immunomorphological staining of specimens prepared from human carotid arteries with anti-collagen type I antibodies reveals large amounts of type I collagen in the subendothelium of lipid fibrous plaques. Collagen type I-containing structures, once in direct contact with blood after plaque rupture, can serve as potential targets for selective delivery of liposomes and erythrocytes to these areas. To verify this rationale, [14C]cholesterol oleate-containing liposomes were conjugated with bovine or human anti-collagen type I antibodies or human plasma fibronectin. Biotin derivatives of human anti-collagen type I antibody were coupled to human erythrocytes. Modified liposomes and erythrocytes were perfused in situ through segments of bovine, rabbit, or human arteries partially denuded with a balloon catheter prior to perfusion. After perfusion, the control and denuded areas were excised and subjected to scanning electron microscopic analysis and measurements of associated radioactivity. It was found that conjugates of liposomes or erythrocytes with anti-collagen type I antibodies or fibronectin are selectively bound by endothelium-free zones of arterial segments. Carrier-directed targeting of drug-laden liposomes and erythrocytes to thrombosis-prone areas of arterial lumen is discussed.  相似文献   
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