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Pharmaceutical Chemistry Journal - An HPLC-MS method for simultaneous quantitative determination of a novel gestagenic pharmaceutical and two of its metabolites in rat and rabbit blood sera was...  相似文献   
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The paper presents results of the investigation with 8 male subjects 25 to 36 y.o. attesting the existence of relation between stress tolerance evidenced from the data about tracking function during extended continuous wakefulness and the sympathetic activity assessed by heart rate values. Based on there results, the higher stress tolerance, the lower baseline sympathicotonia and the stronger sympathetic reactions to adequate stimuli.  相似文献   
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Overall 1580 children from the regions with unsafe radiation situation were examined comprehensively at different times after the accident. The data obtained were correlated to the results of examining 610 children of the control group. The basic group children manifested a higher incidence of diverse alterations on the part of many organs and systems, which was accompanied by an increase of free radical processes signs of destabilization of cellular membranes, activation of blood cell metabolism, suppression of the T cell component of immunity in the presence of vegetovascular dysfunction. A tendency was noted toward normalization of these alterations seen over time after the accident. No clear-cut dose-effect dependence was found.  相似文献   
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Both variants of HIV-1 reported in the literature: slow/low and rapid/high types, were detected among the strains isolated from the subjects examined in 4 foci of HIV-1 infection in the south of the RSFSR and Byelorussia. All the 17 strains isolated in the southern RSFSR foci belonged to the slow/low type and had a low and unstable replication potential in donor peripheral blood mononuclear cells and in MT-4 cell line. All of them were isolated from subjects with asymptomatic infection and from children with initial clinical manifestations of the disease. Only one strain isolated in Byelorussia belonged to the rapid/high type. Its replicative activity was very similar to that of the classical HIV-1--HTLV-IIIB strain. Long-term (up to 7 months) propagation of slow/low strains did not result in any increase of their replicative activity. The capacity to form syncytia was found not only in the rapid/high type strains but also in the majority of slow/low strains under study.  相似文献   
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Pharmaceutical Chemistry Journal -  相似文献   
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The article deals with the results of studying regional microcirculation in 550 patients with chronic arterial insufficiency. Radioisotope study of blood flow in the muscles with isotopes 131I or 133Xe before and after muscular exertion, morpho-histological++ study of biopsies from a skeletal muscle, histochemical and ultrastructural study of the microcirculatory channel were carried out. Analysis of the findings made it possible to distinguish, according to the changes in circulation in the tissues, three clinical groups of patients (compensated, subcompensated, and decompensated), to determine the indications and contraindications for various types of reconstructive operations, and to prognosticate with high authenticity the outcome of the disease.  相似文献   
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Kinase-related protein (KRP) and caldesmon are abundant myosin-binding proteins of smooth muscle. KRP induces the assembly of unphosphorylated smooth muscle myosin filaments in the presence of ATP by promoting the unfolded state of myosin. Based upon electron microscopy data, it was suggested that caldesmon also possessed a KRP-like activity (Katayama et al., 1995, J Biol Chem 270: 3919–3925). However, the nature of its activity remains obscure since caldesmon does not affect the equilibrium between the folded and unfolded state of myosin. Therefore, to gain some insight into this problem we compared the effects of KRP and caldesmon, separately, and together on myosin filaments using turbidity measurements, protein sedimentation and electron microscopy. Turbidity assays demonstrated that KRP reduced myosin filament aggregation, while caldesmon had no effect. Additionally, neither caldesmon nor its N-terminal myosin binding domain (N152) induced myosin polymerization at subthreshold Mg2+ concentrations in the presence of ATP, whereas the filament promoting action of KRP was enhanced by Mg2+. Moreover, the amino-terminal myosin binding fragment of caldesmon, like the whole protein, antagonizes Mg2+-induced myosin filament formation. In electron microscopy experiments, caldesmon shortened myosin filaments in the presence of Mg2+ and KRP, but N152 failed to change their appearance from control. Therefore, the primary distinction between caldesmon and KRP appears to be that caldesmon interacts with myosin to limit filament extension, while KRP induces filament propagation into defined polymers. Transfection of tagged-KRP into fibroblasts and overlay of fibroblast cytoskeletons with Cy3KRP demonstrated that KRP colocalizes with myosin structures in vivo. We propose a new model that through their independent binding to myosin and differential effects on myosin dynamics, caldesmon and KRP can, in concert, control the length and polymerization state of myosin filaments. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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