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G Hagner 《Immunobiology》1984,167(4):389-397
The erythroleukemic K562 cell line was induced to erythroid differentiation by a variety of agents, including hemin, bleomycin, and cytosine arabinoside. The sensitivity of induced cells to binding and lysis by non-sensitized peripheral blood mononuclear cells (MNC) in agarose was studied in relation to the target cell division rate. Differentiated K562 cells formed a lower proportion of conjugates with MNC, when compared with non-induced controls. The reduction correlated significantly with the level of differentiation, irrespective of the inducer and the proliferative status. The differentiation-induced alterations of lysis, however, were strongly influenced by the modification of target cell growth rate which was caused by the differentiating agent. These data suggest that target cell differentiation has distinct effects upon the steps of recognition and lysis by natural killer cells.  相似文献   
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The use of the original haemolytic plaque reduction technique to measure cytotoxic T lymphocytes (CTL) has been developed further as a rapid screening assay, particularly suitable for limiting dilution analyses. Using hybridoma cells as targets, the cytotoxicity has been measured by the loss of haemolytic plaque formation and by the reduction of the amount of haemolytic monoclonal antibody secreted from viable target cells into the assay supernatants. The assessment of large numbers of cytotoxic samples has been greatly facilitated by quantitating the amount of haemoglobin released in the assay with an automated microELISA multiscanner and by scoring visually using a modification of the spot test. Using these new techniques, relatively high frequency estimates of cytotoxic cell precursors in an allogeneic response (1 in 462 spleen cells) and an anti-fluorescein response (1 in 3970 spleen cells) were obtained.  相似文献   
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中药配伍是中医药临床应用的精华之一,合理配伍是保障中药临床用药有效性和安全性的重要措施。配伍后减毒增效机制的研究是诠释中药配伍合理性的关键内容。中药配伍机制研究正处于从体外到体内、成分到靶标、单一技术到多学科融合研究技术的转变历程,因此提出以“体外成分、体内过程、直接靶标”研究为基础,“中药配伍药理机制研究”为目的,从不同角度和不同层面探索中药配伍后作用机制的研究策略。  相似文献   
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抗癌作用新靶点及其抑制剂的研究进展   总被引:2,自引:0,他引:2  
针对靶点分子或某种发生发展机制来设计抗肿瘤药物的研究工作已取得了相当大的成就.这类药物的特异性强,疗效显著,因此,针对这些新靶点进行药物设计可以使抗肿瘤药物的研究产生一次新的革命.本综述旨在讨论目前抗肿瘤药物研究的潜在的新靶点以及它们相应的抑制剂或拮抗剂.  相似文献   
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目的:探讨立体定向技术和多靶点组合对难治性精神病的治疗意义,综合评估临床疗效。方法:在立体定向基础上,应用CT、电阻值和微电极电生理进行核团定位,对80例难治性精神病患者,采用杏仁核、内侧隔区、扣带回等多靶点组合射频热凝治疗。应用临床疗效总评量表(clinicalgrobalimpressionsscale,CGl)、简明精神病评定量表(briefpsychiatricratingscale,BPRS)、阴性和阳性综合量表(thepostitveandnegativesyndrome,PNSS)精神病评定量表在术后6个月对治疗效果进行评定。结果:依据减分率标准,80例患者中,显著进步46例,进步31,无变化3例。手术前后量表评分有显著差异(P<0.05)无严重并发症和后遗症发生。结论:多靶点组合的立体定向技术是难治性精神病的有效治疗方法之一,靶点组合设计和亚核团的准确定位,对提高疗效,降低并发症有较大意义。  相似文献   
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Production cross-sections of the natNi(p,x)60,61Cu, 56,57Ni, 55,56,57,58Co nuclear reactions were measured in five experiments up to 65 MeV by using a stacked foil activation technique. The results were compared with the available literature values, predictions of the nuclear reaction model codes ALICE-IPPE, TALYS-1.4, and extracted data from the TENDL-2012 library. Spline fits were made on the basis of selected data, from which physical yields were calculated and compared with the literature values. The applicability of the natNi(p,x)57Ni, 57Co reactions for thin layer activation (TLA) was investigated. The production rate for 55Co was compared for proton and deuteron induced reactions on Ni.  相似文献   
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《山东中医杂志》2019,(12):1171-1180
目的:基于网络药理学预测射干治疗支气管哮喘的作用机制。方法:通过中药系统药理学技术平台(TCMSP)检索射干化学成分,Swiss Target Prediction数据库得到射干的预测靶点,通过Gene Cards数据库获取哮喘相关靶点将射干的预测靶点与哮喘相关靶点进行映射得到射干治疗哮喘的预测靶点。通过Cytoscape(3.6.0)软件,生成射干治疗哮喘的蛋白与蛋白相互作用(PPI)网络。通过DAVID网站(基因百科全书)进行KEGG通路分析,运用systems Dock网站对预测靶标与其对应的成分进行分子对接。结果:射干活性化合物有17种,筛选出射干可能与哮喘相关的靶点74个,关键靶点共16个,包括雌激素受体α(ESR1)、蛋白激酶C-α(PRKCA)、醛糖还原酶(AR)、蛋白激酶C-delta(PRKCD)、蛋白质激酶C-β(PRKCB)等。通过KEGG通路分析得到128条通路,结合文献检索,筛选出治疗哮喘的可能通路为20条,主要分为以下四类,①气道炎症相关通路:PI3K-Akt信号通路、趋化因子信号通路、MAPK信号通路等;②气道平滑肌相关通路:Ras信号通路、Hippo信号通路、钙信号通路等;③血管增生相关通路:VEGF信号通路;④免疫相关通路:T细胞受体信号通路、Toll样受体信号通路。结论:射干通过多靶点、多通路治疗哮喘,其机制可能与气道炎症相关通路、气道平滑肌相关通路、血管增生相关通路、免疫相关通路的作用相关。  相似文献   
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Hepatocellular carcinoma (HCC) is a complex and heterogeneous tumor most commonly associated with underlying chronic liver disease, especially hepatitis. It is a growing problem in the United States and worldwide. There are two potential ways to prevent HCC. Primary prevention which is based on vaccination or secondary prevention involving agents that slow down carcinogenesis. Several pathways have been thought to play a role in the development of HCC; specifically, those involving vascular endothelial growth factor (VEGF)‐mediated angiogenesis, WNT, phosphatidylinositol 3‐kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR), AMP‐activated protein kinase (AMPK), and c‐MET. Currently, there are only a limited number of drugs which have been proven as effective treatment options for HCC and several clinical trials are testing drugs which target aberrations in the pathways mentioned above. In this review, we discuss currently approved therapies, monotherapies and combination therapy for the treatment of HCC.  相似文献   
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