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尿激酶受体的结构与功能研究进展 总被引:2,自引:0,他引:2
尿激酶受体(uPAR)是纤溶系统的重要成份,与uPAR作用后和体内多种生理病理过程关系密切。本综述uPAR的分子型式与结构特症,uPAR对细胞表面某些蛋白质水解的介导,激活生长因子,以及介导uPAR-PAI复合物的内吞清除和信号转导等功能。由此进一步阐明体内纤溶系统的作用及其在肿瘤治疗中的临床意义。 相似文献
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纤溶酶原在金黄色葡萄球菌感染中的作用 总被引:1,自引:0,他引:1
金黄色葡萄球菌菌体表面有多种纤溶酶原受体,包括次黄嘌呤单核苷酸脱氢酶、核糖核苷酸还原酶、α-烯醇化酶和3-磷酸甘油醛脱氢酶等,它们均可以与纤溶酶原结合。与细菌结合的纤溶酶原可被宿主的纤溶酶原激活剂(组织型纤溶酶原激活剂和尿激酶型纤溶酶原激活剂)或葡萄菌属的纤溶酶原激活剂(葡激酶)激活为纤溶酶。细菌表面的纤溶酶有利于其降解宿主胞外基质,穿越组织屏障,因此哺乳动物的纤溶酶原可能在金黄色葡萄球菌感染宿主过程中起重要作用。 相似文献
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葡萄球菌激酶作为新型溶栓剂的研究进展 总被引:2,自引:0,他引:2
近年来对溶栓剂的研究取得了很好的成果,主要集中在单链尿激酶型纤溶酶原激活剂(scuPA),组织型纤溶酶原激活剂(tPA),葡萄球菌激酶(SaK)等。葡萄球菌激酶(SaK)是一种激活溶纤维蛋白的制剂,它与纤溶酶原(Plg)形成1∶1的复合体,使后者转变为纤溶酶(Pli)后激活其他分子变为Pli。从葡激酶的溶栓作用机制,包括与纤溶酶(原)等因子的结合作用,葡激酶的高级结构,抗原性等问题以及近年来有关葡激酶作为新一代溶栓的研究进展进行了综述,并指出进一步利用蛋白质工程,对葡激酶进行分子改造的设想。 相似文献
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单链尿激酶型纤溶酶原激活物的结构和性质 总被引:2,自引:0,他引:2
单链尿激酸型纤溶酶原激活物(scuPA)是一种丝氨酸蛋白酶,由411个氨基酸组成单一多肽链结构,是尿激酶的前体形式。它可特异地激活血栓局部的纤溶酶而启动纤溶系统,并与组织型纤溶酶原激活物(tPA)有协同作用,是一种有广泛前途的溶栓物质。 相似文献
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免疫亲和层析法纯化单链尿激酶型纤溶酶原激活剂 总被引:1,自引:0,他引:1
尿激酶原 (Pro urokinase ,pro UK) ,也称单链尿激酶型纤溶酶原激活剂 (Single chainurokinase typeplasminogenactivator,scu PA) ,与t PA一样是第二代溶栓药物。给药时 ,保持无活性的酶原状态 ,只激活被纤维蛋白吸附的纤溶酶原 ,而对游离的纤溶酶原没有作用 ,即只在血栓表面才能活化转变为双链尿激酶 (Two chainurokinase typeplasminogenactivator,tcu PA或UK) ,因而具有较高的特异性溶血栓作用[1 ] 。尿激酶原… 相似文献
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张宇清 《国外医学:分子生物学分册》2000,22(6):359-363
纤溶酶原激活剂抑制物2型(PAI-2)是一种多功能蛋白质,除了能有效抑制尿激酶(uPA)和双链组织型纤溶酶原激活物(tPA)而调节纤溶活性外,还参与了很多其它的生理病理过程,例如组织重建、胚胎发育、感染、免疫系统发育、肿瘤浸润和迁移等。更有研究表明胞内型PAI-2在抑制细胞凋亡方面也发挥着重要作用。本文就近年来PAI-2抑制细胞凋亡的研究进展作一综述。 相似文献
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纤溶酶原(PLG)经激活为纤溶酶(PLM)后,除了发挥纤溶和栓溶作用,还广泛参与胚胎发育、组织重构、伤口愈合等生理过程.近年来研究显示:PLM还与炎症、自身免疫、肿瘤和神经变性等存在紧密联系,而且已在细胞表面发现十几种PLG受体(PLGR)、结合蛋白.我们综述了这些受体和结合蛋白的结构、信号通路和致病机制方面的研究进展,从而为进一步理解纤溶系统的功能、发展新的诊疗方法提供思路. 相似文献
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尿激酶型纤溶酶原激活剂的研究 总被引:1,自引:0,他引:1
尿激酶型纤溶酶原激活剂u-PA(urokinase-type plasminogen activator)属于丝氨酸蛋白酶类,能激活细胞外基质中丰富的纤溶酶原生成纤溶酶,从而催化细胞外基质降解,对纤溶和癌细胞侵染及扩散等一系列生理和病理过程中发生的胞外蛋白水解起重要调节作用。 人u-PA基因位于第10号染色体之上,表达产生一个约54kD的单链糖基化多肽——尿激酶原。尿激酶原经纤溶酶在其158位赖氨酸 相似文献
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In experiments on Black Sea skates (Raja clavata), the potential of the receptor epithelium of the ampullae of Lorenzini and spike activity of single nerve fibers connected to them were investigated during electrical and temperature stimulation. Usually the potential within the canal was between 0 and –2 mV, and the input resistance of the ampulla 250–400 k. Heating of the region of the receptor epithelium was accompanied by a negative wave of potential, an increase in input resistance, and inhibition of spike activity. With worsening of the animal's condition the transepithelial potential became positive (up to +10 mV) but the input resistance of the ampulla during stimulation with a positive current was nonlinear in some cases: a regenerative spike of positive polarity appeared in the channel. During heating, the spike response was sometimes reversed in sign. It is suggested that fluctuations of the transepithelial potential and spike responses to temperature stimulation reflect changes in the potential difference on the basal membrane of the receptor cells, which is described by a relationship of the Nernst's or Goldman's equation type.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. I. M. Sechenov, Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Pacific Institute of Oceanology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Neirofiziologiya, Vol. 12, No. 1, pp. 67–74, January–February, 1980. 相似文献
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N. P. Vesselkin Yu. V. Natochin 《Journal of Evolutionary Biochemistry and Physiology》2010,46(6):592-603
Evolution of living organisms is closely connected with evolution of structure of the system of regulations and its mechanisms.
The functional ground of regulations is chemical signalization. As early as in unicellular organisms there is a set of signal
mechanisms providing their life activity and orientation in space and time. Subsequent evolution of ways of chemical signalization
followed the way of development of delivery pathways of chemical signal and development of mechanisms of its regulation. The
mechanism of chemical regulation of the signal interaction is discussed by the example of the specialized system of transduction
of signal from neuron to neuron, of effect of hormone on the epithelial cell and modulation of this effect. These mechanisms
are considered as the most important ways of the fine and precise adaptation of chemical signalization underlying functioning
of physiological systems and organs of the living organism 相似文献
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