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991.
高山红景天多糖对小鼠抗柯萨奇B5病毒感染能力的研究 总被引:11,自引:0,他引:11
对感染柯萨奇B5病毒(CVB)小鼠模型研究结果表明,高山红景天多糖对发病小鼠心肌功能改善和免疫功能提高均具有明显的促进作用。增强了小鼠抗CVB5感染的能力,并对由CBV感染性疾病也有一定的防治作用。 相似文献
992.
应用核酸分子杂交技术检测心肌炎组织中的肠道病毒RNA 总被引:4,自引:0,他引:4
用生物素标记pCBIII/35和pCBIII/51肠道病毒属特异性探针,对45心肌炎和心肮病尸检或心肌活检心脏组织进行原位杂交,结果显示:12例(26.6%)存在肠道病毒RNA。柯萨基B3病毒型特异性探针pCBIII/29进一步杂交表明,12例经证实存在肠道病毒RNA的心肌组织中5例(41.7%)出现阳性杂交信号。阳性杂信号主要位于单个或多个心肌细胞的胞浆和心肌的间质组织,偶见竽心肌小血管内皮细胞 相似文献
993.
广西人群DNA修复基因XRCC3多态性与肝细胞癌遗传易感性关联分析 总被引:1,自引:0,他引:1
目的 探讨DNA修复基因X线修复交叉互补因子3(X-ray cross-complementing group 3,XRCC3)基因Thr241Met多态性与黄曲霉毒素B1(aflatoxin B1,AFB1)相关性肝细胞癌(hepatocellular carcinoma,HCC)遗传易感性的相关性.方法 应用PCR技术对AFB1高污染区广西地区257例HCC患者和711名对照人群的XRCC3基因多态性进行检测,进行的病例对照研究.结果 (1)XRCC3 3种基因型(Thr/Thr、Thr/Met、Met/Met)中带有Met者与HCC的易感性相关,且这种相关性与Met数量呈正相关(校正风险值OR分别为2.20和8.56);(2)XRCC3突变基因型多态与血白细胞AFB1-DNA加合物水平在HCC发生过程中存在协同作用(校正OR:2.34~20.44,P<0.01).结论 XRCC3多态性与HCC易感性相关,且这种多态性与AFB1暴露水平在HCC发生中存在协同作用. 相似文献
994.
995.
Relationship between a novel human cytotoxin (factor 2) produced by a B cell line (Karpas 160) and phorbol-myristate-acetate-associated cytotoxicity.
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We found that 160b cells, a subclone of Karpas 160 human B cell line, spontaneously secreted a novel cytotoxin, factor 2 (F2). F2 was also extracted from the cells by 60% ammonium sulphate, 0.5% CHAPS and 0.28% Triton X-114. We were able to show that phorbol myristate acetate (PMA) greatly enhanced the production of F2, and PMA may also account for part of the putative F2 cytotoxic activity to K562 cells in crude preparations. We compared the cytotoxic effect of F2 with PMA-associated F2-like cytotoxicity to K562 cells as well as the adequacy of our schemes to purified F2 with regard to its separation from PMA. We found that it was possible to separate PMA from F2 preparations by gel filtration and Rotofor preparative isoelectric focusing. The fate of PMA was also monitored with 3H-PMA and chromatographic profiles of 3H-PMA were studied using DE52 and gel filtration chromatography. We were able to establish that less than 2.9% of the cytotoxicity to K562 was due to PMA. We also found that the radioactive peaks and cytotoxicity peaks to K562 were not well correlated, indicating that the cytotoxicity was not mainly due to remaining PMA. Activated charcoal removed virtually all F2 and PMA but not tumour necrosis factor activity. Our results also showed that cytotoxicity to K562 resulting from F2 or PMA-associated proteins had different physicochemical properties, indicating that they are different molecular entities. These findings are consistent with the earlier observation that 160 cells produce F2 spontaneously and that PMA can amplify its production significantly. 相似文献
996.
首次及重复感染HCV后抗体及HCV RNA的动态观察 总被引:6,自引:2,他引:6
本文报道对首次感染HCV的14人与重复输入含HCV血的11位感染者进行长达一年半的动态观察,总结出输入大量含HCV血后导致的感染者在自然状态下HCV RNA及抗体变化的规律。7/8再次输入400ml以上含HCV血的感染者,其自身存在的高滴度抗体在受血后1~3个月下降0.5~1.0OD值。首次输出含HCV血的感染者中,11/14的感染者3个月内ALT高于参考值的3倍以上,而再次输入含HCV血的患者中 相似文献
997.
兔中性粒细胞防御素对HL—60细胞毒性及对病毒的直接灭活作用 总被引:1,自引:0,他引:1
本研究从新西兰家兔腹腔渗出中性粒细胞溶酶体内提取酸溶性组分,经制备性AU-PAGE获得纯化的防御素(NP1和NP2),SDS-PAGE测定分子量为3kd左右。以HL-60细胞作靶细胞,当NP1或NP2在100μg/ml浓度时,可杀死60%以上的HL-60细胞。NP1(260μg/ml)还可直接灭活单纯疱疹病毒I型和乙型流感病毒,分别使病毒感染滴度降度98.2%和90%。本研究结果提示,中性粒细胞可 相似文献
998.
D Kabelitz 《Immunobiology》1985,169(4):436-446
We have analyzed the regulatory effects of two classes of tumor promoters, phorbol diesters and indole alkaloids, on human natural killer (NK) cell activity in vitro. In accordance with previous reports, we found that 12-O-tetradecanoylphorbol-13-acetate (TPA) inhibited natural killing against K 562 targets by unseparated mononuclear cells. Here, suppression of NK required the presence of adherent cells (macrophages). Contrary to the results obtained with K 562, tumor promoter-induced suppression of NK activity tested against U 937, another cell line of known NK susceptibility, was independent of the presence of adherent cells. Thus, NK cytotoxicity of effector cells rigorously depleted of adherent and Ia-positive cells was still inhibited when assayed against U 937, while it was generally enhanced when tested against K 562. Identical results were obtained with teleocidin and dihydroteleocidin B, two members of the recently discovered indole alkaloid class of tumor promoters. Therefore, we demonstrate that the regulatory effect of tumor promoters on human NK activity (suppression or stimulation) is determined not only by macrophages at the effector cell level but also by the type of target cell under study. 相似文献
999.
J. M. Vance M. A. Pericak-Vance R. C. Elston P. M. Conneally K. K. Namboodiri R. S. Wappner P. L. Yu John M. Optiz 《American journal of medical genetics. Part A》1980,7(2):131-140
Serum and/or plasma samples from 360 Whites and 126 Blacks were assayed for activity of the lysosomal hydrolase α-N-acetyl-D-glucosaminidase (NAG). The samples from the Blacks had an increased mean (0.50 nm/ml/min) and standard deviation (0.30 nm/ml/min) compared to those from the Whites (0.29 nm/ml/min and 0.10 nm/ml/min, respectively). After loge transformation and admixture analysis, it was possible to demonstrate the presence of 3 distributions of NAG activity in Blacks and at least 2 in Whites. Segregation analysis of the NAG activity of 29 White half-sib twin families indicated that a genetic model for the inheritance of NAG activity provided a better fit (P < 0.01) with the data than the “environmental” model. Thus, the study suggests the presence of a genetic polymorphism for NAG activity in Black and White populations. The presence of alleles for high and low NAG activity in the normal population could lead to incorrect interpretation of serum carrier tests for Sanfilippo syndrome, type B. 相似文献
1000.
Organization of the thalamostriatal projections in the rat, with special emphasis on the ventral striatum 总被引:9,自引:0,他引:9
The organization of the thalamic projections to the ventral striatum in the rat was studied by placing injections of the retrograde tracer cholera toxin subunit B in the ventral striatum and small deposits of the anterograde tracer Phaseolus vulgaris-leucoagglutinin (PHA-L) in individual midline and intralaminar thalamic nuclei. In order to provide a complete map of the midline and intralaminar thalamostriatal projections, PHA-L injections were also made in those parts of the intralaminar nuclei that project to the dorsal striatum. The relationship of thalamic afferent fibres with the compartmental organization of the ventral striatum was assessed by combining PHA-L tracing and enkephalin immunohistochemistry. The various midline and intralaminar thalamic nuclei project to longitudinally oriented striatal sectors. The paraventricular thalamic nucleus sends most of its fibres to medial parts of the nucleus accumbens and the olfactory tubercle, whereas smaller contingents of fibres terminate in the lateral part of the nucleus accumbens and the most ventral, medial, and caudal parts of the caudate-putamen complex. The projections of the parataenial nucleus are directed towards central and ventral parts of the nucleus accumbens and intermediate mediolateral parts of the olfactory tubercle. The intermediodorsal nucleus projects to lateral parts of the nucleus accumbens and the olfactory tubercle and to ventral parts of the caudate-putamen. The projection of the rhomboid nucleus is restricted to the rostrolateral extreme of the striatum. A diffuse projection to the ventral striatum arises from neurons ventral and caudal to the nucleus reuniens rather than from cells inside the nucleus. Fibres from the central medial nucleus terminate centrally and dorsolaterally in the rostral part of the nucleus accumbens and medially in the caudate-putamen. Successively more lateral positions in the caudate-putamen are occupied by fibres from the paracentral and central lateral nuclei, respectively. The lateral part of the parafascicular nucleus projects to the most lateral part of the caudate-putamen, whereas projections from the medial part of this nucleus terminate in the medial part of the caudate-putamen and in the dorsolateral part of the nucleus accumbens. Furthermore, a rostral to caudal gradient in a midline or intralaminar nucleus corresponds to a dorsal to ventral and rostral to caudal gradient in the striatum. In the ventral striatum, thalamic afferent fibres in the "shell" region of the nucleus accumbens avoid areas of high cell density and weak enkephalin immunoreactivity.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献