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991.
Seventy-eight hearts from persons, who had not suffered any cardiovascular disorders during their life time, have been studied. Microcirculatory bed vessels are revealed by impregnation with silver nitrate after V. V. Kuprianov. The values of the capillary diameters obtained are mathematically treated using T. H. Bayes formula. Periods of individual development of the heart are defined when a high functional activity of the capillary bed of the auricles and ventricles is noted. Evidently, this is one of the factors contributing to development of the cardiac ischemic disease.  相似文献   
992.
Abnormal structure of type II collagen in a patients with funnel chest   总被引:1,自引:0,他引:1  
The electrophoretical analysis and CNBr-peptide mapping of the collagens, isolated from the costal cartilage of 30 patients with non-classified and syndromal forms of pex excavatum (funnel chest) (27 patients) and pex carinatum (3 patients) was carried out. In case of one patient with the nonclassified form of funnel chest the electrophoretical mobility of CB 9.7-peptide was found to be decreased. The electrophoretical mobilities of other peptides are not markedly changed. The data obtained allow one to suggest the mutation causing the defect in the region about 160 amino acid residues distant from the C-end of alpha 1 (II) chain of type II collagen of the patient.  相似文献   
993.
甜菜多粘菌形态发育过程研究   总被引:2,自引:0,他引:2  
甜菜多粘菌(Polymyxa betae)是一种专性寄生于甜菜根部的低等真菌,可作为甜菜坏死黄脉病毒(BNYVV)的传播介体并与甜菜丛根病的产生有关。对甜菜多粘菌的研究有助于了解其与所传病毒的生物学关系及其在引致甜菜丛根病中所起的作用。本文观察记录了甜菜多粘菌侵染甜菜根系及其在甜菜根细胞中的发育过程,对甜菜多粘菌各主要发育阶段进行了显微镜观察并发现在其游动孢子中有BNYVV粒体存在。根据观察结果并提出了甜菜多粘菌生活史模式图。  相似文献   
994.
In the in vitro experiments the state of glycolytic processes was studied in the rat brain tissues with development of edema induced by injury and administered nicotine and monoiodoacetate as well as with preliminary introduction of phentolamine, benactyzine, aminazine and trifluoperazine. The brain edema is shown to develop against a background of sharp inhibition of glycolysis independent of the initial content of lactic acid in the incubation medium. Phentolamine, benactyzine and aminazine which prevent from the edema contribute to the normal level of the glycolytic processes. Trifluoperazine ineffective with edema does not prevent from glycolysis inhibition. Inhibition of glycolysis resulting from a decrease in the activity of the corresponding enzymic systems is supposed to be one of the main pathogenetic factors of the brain edema development as it leads to deficit of energy necessary for normal water-electrolytic metabolism in cells.  相似文献   
995.
The reaction of the mixed anhydride of [3H]ATP and mesitylenecarboxylic acid and soluble mitochondrial adenosine triphosphatase is accompanied by the covalent binding of one molecule of the inhibitor to a molecule of the enzyme and results in the inhibition of adenosine triphosphatase activity by more than 90%. The electrophoresis of adenosine triphosphatase modified by reaction with the mixed anhydride of [3H]ATP and mesitylenecarboxylic acid in polyacrylamide gel in the presence of sodium dodecyl sulphate showed that the inhibitor is bound to the beta-subunit of the enzyme. The results suggest that ATP may also bind to the beta-subunit of the adenosine triphosphatase with its triphosphate moiety.  相似文献   
996.
Soluble mitochondrial ATPase from bovine heart (factor F1) loses its activity during ATP hydrolyses. The inactivation is accelerated by moderate pressure, which is generated in an ultracentrifuge cell. The rate of inactivation slows down if the concentration of the substrate (MgATP) is diminished. ATP hydrolysis proceeds at an almost constant rate if the substrate concentration is as low as 0.05 mM. One intersubunit cross-link formed by dimethylsuberimidate per molecule of factor F1, prevents its inactivation during the ATPase reaction both without pressure and in an ultracentrifuge. Sedimentation coefficients measured by the reacting enzyme centrifugation method of both unmodified factor F1 at a low (about 0.05 mM MgATP) substrate concentration and of its dimethylsuberimidate cross-linked form in the presence of 10 mM MgATP, were determined to be s20, w = 12.4 +/- 0.4 S. The value is the same as that obtained by the conventional boundary sedimentation method in the absence of the substrate. This result testifies to the fact that the conformation of reacting factor F1 in solution is similar to that of the enzyme in the absence of the substrate.  相似文献   
997.
The effect of the thymus cells of the C57BL/6 mice on the colony forming ability of the stem hemopoietic cells of the embryonic liver and bone marrow of young (3 months) and old (2 years) mice was studied their joint transplantation into the mice (CBAXXC57BL/6) F1. The stimulating effect of the thymus cells on the colony forming ability of the stem hemopoietic cells of different age depends both on the dose of the stem hemopoietic cells of embryonic liver and the dose of T-lymphocytes. A suggestion is put forward that the stimulating effect of the thymus cells on the colony formation is due to their interaction with the stem cells in the G2 phase of the mitotic cycle.  相似文献   
998.
The study of RNA functions in a cell is based on the methods of labeling and detection of these molecules. In recent years, considerable progress has been made in this area, making it possible to detect RNA in amounts to one molecule with high specificity and to track the dynamics of spatial RNA distribution in the living cell. The review presents the latest developments in the field of in situ hybridization and the use of RNA aptamers and RNA-binding proteins. The prospects of using the CRISPR-Cas system for RNA visualization are discussed in detail.  相似文献   
999.
1000.
包膜尿素在华北平原夏玉米上的应用   总被引:5,自引:0,他引:5  
易镇邪  王璞  陈平平  屠乃美  兰林旺 《生态学报》2008,28(10):4919-4928
通过连续2a的大田试验,比较研究了尿素与包膜尿素对夏播玉米郑单958和农大108产量、水分利用效率(WUE)、氮肥利用率(NUE)与土壤无机氮动态的影响,结果表明:产量与WUE随施氮量增大而增大,两种氮肥间差异不显著;包膜尿素NUE较尿素高,2004年郑单958N90kg/hm^2与农大108N180ks/hm^2条件下提高显著;施氮对土壤无机氮动态的影响具有年际间差异:2004年不施氮条件下一般呈“V”型变化趋势,施氮使其向“N”型或倒“V”型转变,而2005年施氮与不施氮条件下均呈“N”型变化趋势;施氮使土壤无机氮含量明显提高,包膜尿素较尿素效果更明显;土壤无机氮含量,包膜尿素处理以表土层最高,而尿素处理,特别是尿素N180kg/hm^2处理9叶展至吐丝期以下层土壤较高,2004年表现尤为明显。可见在降水量较多的年份,包膜尿素缓释效应明显,能有效控制无机氮的下移。华北平原夏玉米季以包膜尿素替代尿素、以一次性基施替代基肥+追肥是完全可行的,能达到省工、增效、环保目的。  相似文献   
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