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最近我们从全国动物学科研单位和高等院校借调来大批的角蝉科标本,进行系统的分类研究,从中发现有二新属及二新种,均采自云南西双版纳,现在先把它们加以记载。 相似文献
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Glutamate release and synaptic vesicle heterotypic/homotypic fusion were characterized in brain synaptosomes of rats exposed to hypergravity (10 G, 1 h). Stimulated vesicular exocytosis determined as KCl-evoked fluorescence spike of pH-sensitive dye acridine orange (AO) was decreased twice in synaptosomes under hypergravity conditions as compared to control. Sets of measurements demonstrated reduced ability of synaptic vesicles to accumulate AO (10% higher steady-state baseline level of AO fluorescence). Experiments with preloaded l-[14C]glutamate exhibited similar amount of total glutamate accumulated by synaptosomes, equal concentration of ambient glutamate, but the enlarged level of cytoplasmic glutamate measuring as leakage from digitonin-permeabilized synaptosomes in hypergravity. Thus, it may be suggested that +G-induced changes in stimulated vesicular exocytosis were a result of the redistribution of intracellular pool of glutamate, i.e. a decrease in glutamate content of synaptic vesicles and an enrichment of the cytoplasmic glutamate level. To investigate the effect of hypergravity on the last step of exocytosis, i.e. membrane fusion, a cell-free system consisted of synaptic vesicles, plasma membrane vesicles, cytosolic proteins isolated from rat brain synaptosomes was used. It was found that hypergravity reduced the fusion competence of synaptic vesicles and plasma membrane vesicles, whereas synaptosomal cytosolic proteins became more active to promote membrane fusion. The total rate of homo- and heterotypic fusion reaction initiated by Ca2+ or Mg2+/ATP remained unchanged under hypergravity conditions. Thus, hypergravity could induce synaptopathy that was associated with incomplete filling of synaptic vesicles with the neuromediator and changes in exocytotic release. 相似文献
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中国的广翅蜡蝉科附八新种 总被引:1,自引:0,他引:1
广翅蜡蝉科的种类,多数为害木本植物,少数为害禾本科草本植物,有的是果树、森林和农作物的害虫。但关于广翅蜡蝉科的研究,过去很不充分,我国的种类、分布与寄主关系,至今还不清楚。1935年胡经甫的昆虫名录中列入11种(包括3种同物异名),1959年《中国果树病虫志》中列了5种。 我们根据三十年来在全国各地的采集调查,和全国兄弟单位提供的标本,共鉴定出26种。本文着重记录它们的分布及其为害植物,并记载新种8种。 相似文献
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金翅夜蛾亚科八新种及一些种类的订正 总被引:2,自引:0,他引:2
金翅夜蛾亚科的种类,有的在外形上非常相似,因之过去文献记载常有混淆的地方和鉴定上的错误。本文讨论了一些种类的区别,纠正某些错误的记载,并报道8个新种。 所有新种的模式标本都暂在西北农学院昆虫标本室保存。 相似文献
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The present study involves the testing and characterization of synaptic vesicle (SV) docking and fusion as the steps of exocytosis using two different approaches in vitro.The interaction of SVs was determined by the changing of particles size in suspensions by the method of dynamic light scattering (DLS). Fluorescence assay is represented for studying the mechanism of SV membrane fusion. The sizes of membrane particles were shown to increase in the medium containing cytoplasmic proteins of synaptosomes. Therefore, the cytosolic proteins are suggested to promote the SVs into close proximity where they may become stably bound or docked. The specific effect of synaptosomal cytosolic proteins on the interaction of SVs in the cell-free system was demonstrated. The incubation of SVs with liver cytosol proteins or in the bovine serum albumin solution did not lead to the enlargement of the particles size. The fusion reaction of the SVs membranes occurred within the micromolar range of Ca2+ concentrations. Our studies have shown that in vitro process of exocytosis can be divided into Ca2+-independent step, termed docking and followed by fusion step that is triggered by Ca2+. The role of cytosolic proteins of synaptosomes in docking and fusion of SVs in cell-free system was further confirmed. 相似文献
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Oleg Ya Shatursky Kyrylo Yu Manoilov Oksana B. Gorbatiuk Mariya O. Usenko Dariia A. Zhukova Andriy I. Vovk Oleksandr L. Kobzar Irene O. Trikash Tatiana A. Borisova Denys V. Kolibo Serhiy V. Komisarenko 《Biophysical journal》2021,120(12):2577-2591
The geometry of the channel formed by nontoxic derivative of diphtheria toxin CRM197 in lipid bilayer was determined using the dependence of single-channel conductance upon the hydrodynamic radii of different nonelectrolytes. It was found that the cis entrance of CRM197 channel on the side of membrane to which the toxoid was added at pH 4.8 and the trans entrance on the opposite side at pH 6.0 had effective radii of 3.90 and 3.48 Å, respectively. The 3-alkyloxycarbonylmethyl-5-(2-hydroxyethyl)-4-methyl-1,3-thiazolium salts reversibly reduced current via CRM197 channels. The potency of the blockers increased with increasing length of alkyl chain at symmetric pH 6.0 and remained high and stable at pH 4.8 on the cis side. Comparative analysis of CRM197 and amphotericin B pore size with the inhibitory action of thiazolium salts revealed a significant increase in CRM197 pore dimension at pH 6.0. Addition of thiazolium salt with nine carbons alkyl tail increased by ~30% the viability of human carcinoma cells A431 treated with diphtheria toxin. 相似文献
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