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A comparative evaluation of rheographic changes in regional pulmonary hemodynamics and renin-angiotensin and kinin-kallikrein activities was carried out on 9 volunteers exposed to antiorthostatic hypokinesia (-8 degrees) for 14 days. It was found that pulmonary circulation shifted in the apical direction due to increase in arterial tonicity and phasic variations of venous lumen. During the study blood renin increased significantly (P less than 0.05) whereas prekallikrein and kallikrein inhibitor varied insignificantly. It was concluded that the renin-angiotensin system played and important role in the changes of functional topography of pulmonary circulation in simulated microgravity conditions.  相似文献   
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Summary: A new principle for the design of dendritic macromolecules – the ionic binding of linear chain polyelectrolyte with oppositely charged focal ionogenic groups of dendrons – has been developed. The majority of the dendritic ionic complexes (DICs) are prepared with poly(styrenesulfonic acid) (PSS) as a polymeric core and L ‐aspartic acid dendrons of different generations. Two series of DICs were prepared using PSS and aspartic dendrons bearing terminal (located at the external periphery) methoxycarbonyl and hexyloxycarbonyl groups (C1‐n and C6‐n respectively where n is the generation number). Ionic binding of about 100% was found for dendrons of Generation 1–3. The solubility of the DICs was examined and the DICs prepared were studied by IR spectroscopy, 1H NMR and viscometry.

Dendritic ionic complexes prepared using poly(styrenesulfonic acid) acid and aspartic dendrons bearing terminal methoxycarbonyl and hexyloxycarbonyl groups.  相似文献   

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We studied the effects of cis-dichlorodiammine platinum (II) on different pathways of cell death in cultured Ehrlich ascites carcinoma in vitro and on subsequent growth of transplanted tumor in vivo. One-hour incubation with the cytostatic modulated apoptosis in cell culture. However, exposure of cell culture to a minimal effective concentration of cis-platinum(II)diammine dichloride promoted the growth of transplanted tumor.  相似文献   
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The multicomponent VP-4 vaccine from Klebsiella pneumonia, Staphyloccocus aureus, Proteus vulgaris, Escherichia coli antigens was used to prevent acute respiratory diseases (ARD) at preschoolchildren's establishments. Prevention was effected during an influenza epidemic with a drastic rise in the incidence of ARD. The VP-4 use involved 3 nasal and 6-9 oral administrations of the drug at an interval of 3-4 days. The duration of the course was 26 +/- 4 days. The preventive action of VP-4 on the incidence of ARD was followed up for 14 months after vaccination. One group comprised 89 vaccinated children, a matched group included 69 children whose age was 2 to 6 years. Immunoprophylaxis was found to promote a reduction in the number of children who had 4 ARD episodes or more during the whole follow-up. Administration of VP-4 prevented the development of repeated episodes ARD in a group of children aged 2-3 years and in frequently ill children who had 3 infections or more in the previous year. The slight reactogenicity of the drug and its long-term preventive effect allow this method of immunoprophylaxis to be recommended for frequently ill children, for those at high risk, and for those in the junior age group (under 4 years) before going to preschoolchildren's establishments.  相似文献   
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个体化下肢小腿假肢接受腔设计的生物力学评价技术研究   总被引:3,自引:0,他引:3  
作为传递体重、固定假肢的部件 ,接受腔对于小腿假肢使用的舒适性和方便程度有决定性的作用。本研究建立了基于有限元应力分析的小腿假肢生物力学评价技术平台 ,实现了小腿残端 /接受腔 3D几何建模与信息交互、三维有限元自动建模及应力分析。 3D模型与信息交互的实现基于得到广泛支持的OpenGL技术 ,有限元模型的构建采用了专门针对小腿残端 /接受腔结构特点的自动建模方法 ,通过构建档案数据库系统作为整个系统的操作平台。该技术平台可与现有的CAD/CAM系统相结合 ,为接受腔的个体化设计提供生物力学定量化依据。其临床应用将改善传统的设计流程 ,提高设计效率。同时 ,它也是未来构建接受腔设计专家 /智能系统的基础。  相似文献   
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The metabolic state of rat liver was studiedin vivo 1, 6, and 18 h after single hyperthermia (42°C). It was shown that intracellular compensatory reactions involved in restoration of the energy state and realization of endogenous cytoprotective mechanisms play a role during recovery. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 4, pp. 414–416, April, 2000  相似文献   
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