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31.
15只大鼠分别于左肺门区注入辣根过氧化物酶(HRP,5只)、快蓝(FB,5只),右肺内支气管腔内注入FB(5只),在房壁心内神经节发现示踪剂标记神经细胞。三组标记率分别为1.4%、2.5%及0.9%。标记细胞的出现证实心内神经节部分神经细胞亦是支配呼吸系统肺内、外支气管和肺血管壁、肺泡壁的局部神经细胞;提示心内神经节参与了心肺间功能相互联系及协调的调控。 相似文献
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The afferent nervous supply to the thymus gland has been investigated by means of the retrograde transport of horseradish peroxidase. It has been shown that the thymus receives an afferent supply from the nodose ganglia of the vagus and from the dorsal root ganglia C1–C7. The afferent innervation of the right and left thymic lobes is bilaterally organized; the fibers of a small celled population of nodose ganglion neurons cross outside the thymus and those of a larger celled population cross within the thymus gland. The functional implications of these findings are discussed in the context of central nervous system-immune system interactions. 相似文献
34.
用差速离心方法分离提取荷Lewis肺癌小鼠癌组织和肝组织富含溶酶体部分,并以溶酶体标志酶酸性磷酸酶(ACP)的游离酶和总酶活性比值作为观察溶酶体膜稳定性变化的指标,观察了亚硒酸钠对两种组织ACP酶活性和膜稳定性的影响。发现硒对癌组织和肝组织ACP活性的异常升高有抑制作用、稳定溶酶体膜,在癌瘤增殖前期作用明显(P<0.05)。提示这种拮抗效应与硒直接和间接的抗脂质过氧化有关。 相似文献
35.
Takeyuki Kohno Eiji Ishikawa Satoru Sugiyama Syuji Nakamura 《Journal of clinical laboratory analysis》1988,2(1):19-24
A novel enzyme immunoassay of anti-insulin IgG in human serum is described. A serum sample containing anti-insulin IgG was treated with dextran-charcoal at pH 6.0 to remove endogenous insulin and subsequently incubated with dinitrophenyl biotinyl nonspecific rabbit IgG-insulin conjugate. The reaction mixture was further incubated with a rabbit (antidinitrophenyl bovine serum albumin) IgG-coated polystyrene ball to trap the complex formed between anti-insulin IgG and the conjugate. After washing to eliminate nonspecific IgG in the test serum, the polystyrene ball was incubated with dinitrophenyl-L-lysine to elute the complex. The eluate was incubated with an avidin-coated polystyrene ball. Finally, the amount of human anti-insulin IgG in the complex trapped onto the avidin-coated polystyrene ball was measured by incubation with rabbit (antihuman IgG (γ-chain)) Fab'-peroxidase conjugate. This enzyme immunoassay was 1,000-fold more sensitive than the conventional enzyme immunoassay, in which an insulin-bovine serum albumin-coated polystyrene ball was incubated with a serum sample containing anti-insulin IgG and subsequently with rabbit (antihuman IgG (γ-chain)) Fab'-peroxidase conjugate. The principle of the novel enzyme immunoassay can be used to more sensitively measure antibodies for most kinds of haptens and antigens than the conventional enzyme immunoassay. 相似文献
36.
作者观察了在二亚硝基哌嗪(DNP)诱发大鼠鼻咽癌变过程中全血硒浓度和谷胱甘肽过氧化物酶(GSH-PX)活性的变化及硒的作用。实验分5组:①空白对照组(BG);②硒对照组(SG);③DNP对照组(DG);④硒预防组(PG);⑤硒治疗组(TG)。结果显示,于饮水中补硒能提高大鼠血硒浓度和GSH-PX活性,而且能预防鼻咽癌的发生;在实验早期,各给致癌物组酶活性与相应的对照组无差异,后期前者均明显低于后者,且DG血硒浓度明显低于BG,说明肿瘤的形成引起了血中GSH-Px和硒浓度的降低;然而PG和TG血硒与SG无差异,说明血硒浓度的高低易受摄取量的影响,提示在评估肿瘤时,血GSH-PX活性也许比血硒更有用。经分析,大鼠全血GSH-PX活性与硒浓度之间有正相关关系(r=0.61,P相似文献
37.
Wheat germ agglutinin-horseradish peroxidase conjugate was injected in the unilateral superior cervical ganglion (SCG), and the projection pathways of postganglionic sympathetic nerve fibers innervating the cochlea were traced in the rat. The labeled axons advanced along the internal carotid artery (ICA), and a few advanced caudally in the major petrosal nerve (MPN) and entered the facial nerve, while the majority ran rostral to the pterygopalatine ganglion at the point where they crossed the MPN in the carotid canal. The rest of the labeled fibers remained on the surface of the ICA and advanced to the cranial cavity. Most of the labeled fibers along the facial nerve joined the cochlear nerve and finally reached the osseous spiral lamina through the spiral ganglion. Some of the labeled fibers ran along the anterior inferior cerebellar artery from the basilar artery which was previously thought to have been the only pathway. We could not find any labeled fiber on the modiolar artery from anterior inferior cerebellar artery in the cochlea. These observations are consistent with our hypothesis that the sympathetic fibers innervating the neural tissues or related structures follow nerve fibers and meninges as matrices of projection pathways rather than arteries. 相似文献
38.
Evidence to suggest the presence of abnormal metabolism of oxygen free radicals in progressive muscular dystrophy is presented using an animal model. In the superficial pectoral muscles of dystrophic chickens, enzyme activities regulating the metabolism of oxygen free radicals, i.e., catalase, superoxide dismutases and glutathione peroxidase, were significantly elevated within 1 week of hatching. Activities of related enzymes, i.e., glutathione reductase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase were also elevated. In contrast, the specific activity of phosphofructokinase, the rate-limiting enzyme of the glycolytic pathway, was normal during the first 4-week period. These results suggest that there is an increased turnover of oxygen free radicals in the dystrophic muscle. This concept appears important in a further investigation of the pathogenesis and treatment of progressive muscular dystrophies. 相似文献
39.
用尿谷胱甘肽过氧化物酶评定颈椎病的康复疗效 总被引:2,自引:0,他引:2
测定了44例颈椎病患者康复前后尿液中谷胱甘肤过氧化物酶(GSH-Px)活力的变化。患者在治疗前,尿中GSH-Px活力为1080±310U/L((?)±s),与健康对照组相比差异有高度显著性(P<0.001)。推拿和颈牵治疗后尿中GSH—Px活力平均下降38.8%,且下降幅度和疗效之间有着明显的平行关系。据此,我们认为颈椎病的发病可能和体内自由基代谢紊乱有关,同时认为,无创伤的尿GSH—Px活力测定可以作为颈椎病康复疗效评定的客观指标,从而为颈椎病康复疗效的评定提供科学的生化依据。 相似文献
40.
In recent years, a growing interest in the study of peptide antigenicity in relation to the role of flanking sequences and protein topology in processing, presentation, and recognition has been observed. However, the information available on the antigenicity of recombinant fusion proteins and their effect on the selection of antigen receptor repertoires is limited. To analyze the role of molecular topology of T epitopes in a system relevant to human pathology, we have used the bacterially expressed Schistosoma japonicum glutathione S transferase (GST) to construct recombinant antigens containing HIV-1 derived T cell determinants, and human T cell clones specific for these determinants. We found that antigenicity of a given GST—peptide combination was not the same when T cells and antigen presenting cells from different individuals were tested. Our results show that differences in processing and presentation of chimeric proteins are not dictated by the use of diverse restriction elements. We also found that the context in which an antigenic peptide is delivered affects the recruited repertoire as defined according to T cell receptor Vβ usage and fine specificities of selected T cells. 相似文献