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961.
目的 探讨慢性乙型肝炎(CHB)患者肝细胞凋亡与肝组织诱导性一氧化氮合酶(iNOS)、肝脏病理及血清转氮酶水平之间的相关关系.方法 取37例CHB患者和10例正常对照,采用dUTP缺口末端标记技术(TUNEL)检测肝组织中的细胞凋亡情况,免疫组化法检测肝组织iNOS的表达,并常规测定患者肝组织炎症分级和纤维化分期、血清丙氨酸转氨酶(ALT)、HBV DNA水平.结果 所有CHB患者的肝组织中均见到不同程度的TUNEL染色阳性.正常对照肝组织中未见到TUNEL阳性肝细胞.在CHB肝组织中,凋亡指数(A1)与炎症分级(r=0.404,P=0.015)及肝组织iNOS水平(r=0.465,P=0.004)明显相关并有统计学意义,而与血清ALT水平、HBV DNA以及组织学纤维化分期无明显关系.结论 慢性乙型肝炎患者体内氧化应激水平可能是肝细胞凋亡的诱导因素之一,细胞凋亡参与了CHB的肝细胞损伤过程,但并不影响患者的生物化学指标.  相似文献   
962.
目的 为了研究噬菌体D29气溶胶吸入治疗结核分枝杆菌的可行性,测试了噬菌体D29耐雾化能力、喷雾量、气溶胶粒径等气溶胶特性参数.方法 负压实验室气雾柜内发生噬菌体D29气溶胶,TSI3321气溶胶粒径分析仪测试了气溶胶空气动力学直径.Anderson六级空气微生物采样器测试了生物粒子气溶胶中值直径.据雾化前后噬菌体D29的浓度变化及体积变化得到噬菌体D29的雾化时间存活率和雾化量.结果 噬菌体D29气溶胶空气动力学直径为0.872 μm,生物粒子气溶胶中值直径为2.21 μm.噬菌体D29在雾化5、15、30、45、60 min后的存活率分别为89.78%、77.19%、48.86%、33.99%、30.12%.气溶胶的雾化量为232 μl/min.结论 噬菌体D29气溶胶粒径、耐雾化能力及喷雾量等气溶胶参数可以进一步进行动物气溶胶吸入治疗结核分枝杆菌感染方面的研究.  相似文献   
963.
964.
The distribution of HLA antigen frequencies has been studied in patients with affective disorders. There were no significant differences between bipolar patients, unipolar patients, or controls. Preliminary data on HLA antigen distribution in schizophrenic patients are reported. Our negative results in affective disorders are discussed in relation to HLA studies reported from other laboratories, with special reference to some potential methodological problems.  相似文献   
965.
Anterior pituitary cells of the GH line, which secrete prolactin spontaneously, showed spontaneous action potential activity. Thyrotrophin releasing factor, which increases secretion in these cells, caused a prompt increase of action potential frequency. Potassium, another secretagogue, depolarized the cells and sometimes initiated a burst of action potentials at the onset of this effect. The action potentials persisted in tetrodotoxin-containing and Na-free media, but were suppressed by the Ca-channel blocker, methoxyverapamil. Moreover, elevating the extracellular Ca2+ concentration increased the amplitude of the action potentials. These action potentials therefore have a prominent Ca component. This endows them with a particular interest since secretory activity of these cells is known to be dependent on extracellular Ca2+. Ba2+, which can substitute for Ca2+ in maintaining secretion, also substituted for Ca2+ in the maintenance of the action potentials. In addition, Ba2+ prolonged action potentials remarkably: tetraethylammonium was less effective in this regard.The several parallels between known secretory behaviour and electrical phenomena encourage the view that analysis of electrical activity in anterior pituitary cells may provide useful clues to events involved in stimulus-secretion coupling and in the secretory control exerted by the brain.  相似文献   
966.
This report describes a spectrum of respiratory symptoms in workers exposed to trimellitic anhydride (TMA), a biologically reactive chemical used in the plastics industry. Fourteen workers who had worked on a unit which synthesized TMA were evaluated by clinical and immunologic methods. Respiratory syndromes induced by TMA inhalation included asthma and rhinitis of the immediate type, late onset asthma with systemic symptoms, and airway irritation. TMA was shown to couple rapidly to human serum albumin, forming an immunoreactive hapten-protein complex. The workers' immunologic reactivity to this complex could be quantitated and correlated with the three respiratory syndromes. The asthma-rhinitis syndrome was mediated by IgE antibody specific for the TMA hapten. The syndrome of late onset asthma with systemic symptoms was accompanied by elevated levels of TMA-specific IgG antibody. Rheumatoid factor in high titer was found in one worker with IgE-mediated asthma and in two workers with asthma of late onset. Lymphocyte reactivity of TMA-HSA was demonstrated in three workers representative of the three clinical syndromes. Leukocyte histamine release was demonstrated to TMA-HSA in one worker with high levels of IgE antibody specific for TMA-HSA who had severe symptoms of acute rhinitis and asthma.  相似文献   
967.
A laboratory-developed analog signal processor, driven by a conventional polygraph recorder and associated signal conditioning devices, provides automatic heart beat-by-heart beat preprocessing of various cardiovascular functions for input to a laboratory-type minicomputer. The technique of preprocessing individual functions, integrated with the minicomputer system which includes an A/D converter and teletype as input-output peripherals, provides a low-cost data acquisition and reduction system for the on-line computation and analysis of cardiovascular functions in experimental research applications. Such preprocessing more efficiently uses the minicomputer's memory to handle large amounts of information since the digitized data is in the form of one data sample, per function, per heart beat. Preprocessing analog data provides a low density data format and simplified software programs that are ideally suited for the utilization of a minicomputer in this on-line application.  相似文献   
968.
His-tag不影响RSV重组蛋白G1F/M2的免疫原性   总被引:1,自引:0,他引:1  
目的:观察His-tag是否影响RSV重组蛋白G1F/M2的免疫原性。方法:PCR扩增G1和F/M2基因片段,插入表达载体pET-His和pET-DsbA-His中,转化E.coli BL21(DE3),IPTG诱导表达,采用Ni^+螯合亲和层析法纯化得His-G1F/M2和DsbA-His-G1F/M2,将后者用凝血酶消化,再经Ni+螯合亲和层析法纯化得G1F/M2,将His-G1F/M2和G1F/M2免疫BALB/c小鼠,用ELISA测定抗体滴度,MTT法测定细胞毒性T细胞活性(CTL)。结果:两种蛋白在BALB/c小鼠中诱导的RSV特异性抗体和CTL活性无显著差异。结论:His-tag不影响RSV重组蛋白G1F/M2的免疫原性。  相似文献   
969.
目的: 观察丙型肝炎病毒(HCV)核心蛋白(CP)对蛋白激酶R(PKR)表达的影响;定位PKR与CP直接结合的区域。方法: 对Huh-7、转染表达CP的Huh-7及含有全长HCV复制子(replicon) Huh-7细胞株的PKR表达水平及干扰素(IFN)诱导前后replicon Huh-7细胞中HCV结构蛋白和非结构蛋白表达水平作比较;对CP与PKR进行免疫共沉淀试验、谷胱苷肽S转移酶(GST)结合试验。结果: Replicon Huh-7中PKR表达水平高于Huh-7及转染表达CP的Huh-7;IFN诱导后PKR表达增加,且明显抑制HCV结构和非结构蛋白的表达;PKR能与CP直接结合,依赖于PKR的N端1-180氨基酸(aa)。结论: CP能直接作用于PKR N端1-180 aa,导致PKR组成性激活,从而干扰PKR介导的相关信号转导通路。CP与PKR的相互作用是HCV病毒蛋白与细胞蛋白相互作用又一新的模式,在HCV持续感染及肝癌2者发病机制方面可能起重要作用。  相似文献   
970.
Zhang X  Kielian M 《Virology》2005,337(2):344-352
Semliki Forest virus (SFV) membrane fusion is mediated by the viral E1 protein at acidic pH and regulated by the dimeric interaction of E1 with the E2 membrane protein. During low pH-triggered fusion, the E2/E1 heterodimer dissociates, freeing E1 to drive membrane fusion. E2 is synthesized as a precursor, p62, which is processed to mature E2 by the cellular protease furin. Both the dissociation of the p62/E1 dimer and the fusion reaction of p62 virus have a more acidic pH threshold than that of the mature E2 virus. We have previously isolated SFV mutations that allow virus growth in furin-deficient cells. Here we have used such pci mutations to compare the interactions of the p62/E1 and E2/E1 dimers. Our data suggest that there is an important p62/E1 dimer interaction site identified by an E2 R250G mutation and that this interaction is maintained after processing to the mature E2 protein.  相似文献   
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