体外培养周期型马来丝虫感染期幼虫

关于体外培养周期型马来丝虫(periodic Brugia malayi)感染期幼虫(L_3),近年来国内外有一些报道,系应用含哺乳动物组织细胞系或原代细胞的培养系统培养彭亨丝虫和马来丝虫L_3,可使其幼虫发育至Ⅳ期蚴(L-4)或早期成虫(Chen and Howells,1979; Wong et al.,1982;Mak et al.,1983;郑惠君等,1984)。但未见应用含人体组织细胞系的体外培养系统培养布鲁属丝虫L_3的报道。本研究     

人肝癌细胞表皮生长因子受体以及佛波酯对它的调度

Using radioligand binding assay, the presence of epidermal growth factor (EGF) receptors in cells of two human liver cancer cell lines, BEL-7402 and SMMC-7721, was demonstrated. The ligand binding data were analyzed by a computer program. The dissociation constants (KD) of the ligand-receptor binding complex at equilibrium for 7402 and 7721 cells were 1.2 nM and 0.8 nM respectively, and their number of EGF receptors per cell were 6.2 x 10(4) and 2.5 x 10(4) respectively. After the treatment of cells with phorbol 12-myristate 13-acetate (PMA), no change either in the affinity or in the number of EGF receptors was found in 7721 cells. However, in the case of 7402 cells, while the number of receptors, like 7721 cells, remained unchanged, the affinity of EGF receptors displayed a time dependent modulation after PMA treatment. It dropped within the first hour to a KD value of 3.0 nM and then gradually returned to the normal control value at 48 hours or even slightly higher than normal (0.95 nM) at 96 hours of treatment. The modulation or down-regulation of EGF receptors by PMA in 7402 cells was paralleled by the simultaneous inhibition of DNA synthesis in these cells as evidenced from their reduction of 3H-TdR uptake. It is not clear what is the basis for the differences found between 7402 cells and 7721 cells in their number of EGF receptors per cell and their responsiveness to PMA treatment. It might be related to their difference in autocrine secretion of alpha-transforming growth factors.(ABSTRACT TRUNCATED AT 250 WORDS)     

成人及新生儿颅骨铜和锌含量的初步研究

本文系用原子吸收光谱法测定了西安地区10例成人尸体和15例新生儿尸体的颅盖骨内Cu和zn的含量。结果求得成人颅骨中Cu正常含量(均数±标准差)为4.48±3.78mg/kg(干组织重);zn为597.05±472.54mg/kg。新生儿颅骨中Cu和zn的含量分别为1.96±0.76mg/kg;1160.38±859.71mg/kg。结果表明,成人颅骨内Cu含量高于新生儿,而成人颅骨内Zn含量显著低于新生儿。     

人胎脑胶质细胞自发分泌白细胞介素6

自1986年获取人白细胞介素6(IL-6)分子克隆以来,IL-6研究已深入生物医学领域的各个分支。已证明IL-6在免疫系统、造血系统、肝脏代谢等分化发育及功能表达中担负关键的作用。1987年发现建株的星形细胞瘤和胶质细胞瘤在LPS或IL-1刺激后可以表达IL-6 mRNA。1988年发现IL-6可以促进嗜铬细胞瘤(一种检测神经生长因子的细胞模型)向神经元分化,从而揭开了研究IL-6促神经母细胞分化效应的序幕。鉴于上述证据均为间接性证据,尚无法直接证明人中枢神经系     

Construction and packaging of pseudotype retrovirus containing human N—ras cDNA antisense sequence and its biological effects on human hepatoma cells

N-ras is one of the transforming genes in human hepatic cancer cells.It has been found that N-ras was overexpressed at the mRNA and protein level in hepatoma cells.In order to explore the biological roles of N-ras in human hepatic carcinogenesis and the potential application in control of cancer cell growth,a preudotype retrovirus containing antisense sequence of human N-ras was constructed and packaged.A recombinant retrovirus vector containing antisense or sense sequences of N-ras cDNA was constructed by pZIP-NeoSV(X)1.The pseudotype virus was packaged ang rescued by transfection and infection in PA317 and ψ 2 helper cells.It has been demonstrated that the pseudotype retrovirus containing antisense N-ras sequence did inhibit the growth of human PLC/PRF/5 hepatoma cells accompanied with inhibition of p21 expression,while the retrovirus containing sense sequence had none.The pseudotype virus had no effect on human diploid fibroblasts.     

人黑色素瘤细胞分泌的组织纤溶酶原激活剂(t-PA)的纯化

 本文报道了培养的人黑色素瘤细胞分泌的组织纤溶酶原激活剂(t-PA)的纯化方法。Bowes株人黑色素瘤细胞的分泌产物,经CM-Sephadex C--50层析,赖氨酸-Sepharose 4B,苯甲眯-sepharose 4B亲和层析后,即可得到纯化470倍的蛋白纯品。样品经聚丙烯酰胺凝胶电泳鉴定为均一单带,测得其分子量约为72kD。纯化的t-PA与尿激酶相比较,发现前者有更高亲和纤维蛋白的能力。     

人的恶性高热和猪的应激综合征

人的恶性高热和猪的应激综合征是临床症状极其相似、遗传方式不同的两种代谢障碍性疾病,它们直接威胁着人类的生命安全和畜牧业生产。随着医学和基因工程技术的发展,有关专家对这两种病的认识在９０年代初取得了突破性进展。本文在回溯这两种疾病的历史背景的基础上,将...     

人巨细胞病毒小鼠模型的建立

采用HCMV-AD_(169)株实验感染昆明系和BALB/C系小鼠,攻毒后感染急性期BALB/C系小鼠的死亡率(28.57％)高于昆明系小鼠(5.26％)。两种不同品系小鼠的临床症状和HCMV导致的病理损害脑钙化无明显差异。昆明小鼠的发病率(94.74％)高于BALB/C小鼠。     

人分裂细胞核抗原基因片段的筛选、测序及对启动子的分析

经６．６×１０５个克隆筛选,从装在λ噬菌体载体Ｃｈａｒｏｎ３０中的人基因库中筛选到了一个含人分裂细胞核抗原（ＰＣＮＡ）基因的克隆。经Ｓｏｕｔｈｅｒｎ杂交分析插入基因长约１４ｋｂ,有较长的５＇上游区,但３＇端缺少一部分。经亚克隆和测序已确定从５＇上游１２６３ｂｐ到３＇端与λ载体接点共４９６９ｂｐＰＣＮＡ基因片段的核苷酸序列。将ＰＣＮＡ基因启动子核苷酸序列与ＤＮＡ聚合酶α,拓扑异构酶Ⅱα,胸苷酸激酶基因的启动子进行比较有３０％以上同源性,具有“看家基因”特征。在转录起始点的５＇上游几百ｂｐ的范围内都有与ＣＡＴ,ＳＰ１,Ｅ２Ｆ,ＮＦＨＢ,Ｏｃｔ１和ＡＴＦ等转录因子的结合位点相似的核苷酸序列。