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91.
YY1抑制效应的破坏可促进人乳头瘤病毒16型癌基因的转录   总被引:3,自引:1,他引:3  
董小平  刘红 《病毒学报》1999,15(2):125-129
人乳头瘤病毒16型(HPV16)癌基因的表达受病毒早期启动子P97的控制。位于LCR上YY1蛋白结合位点的破坏可明显提高P97的活性。为了观测YY1位点破坏在全基因组范围内对病毒e6/e7基因转录的影响,将构建的带有LCR特异性突变的重组HPV16全基因组DNA和HPV16野毒株DNA转染至培养细胞,同时组建HPV16E6反向序列RNA体外转录质粒。RNase保护试验证实,突变HPV16DNA在短  相似文献   
92.
用富集文库克隆人胰岛素基因组基因   总被引:1,自引:0,他引:1  
通过构建可富集人胰岛素基因的λ噬菌体文库,克隆了人胰岛素基因组基因.首先从中国人血液白细胞中提取到人基因组DNA,用EcoRⅠ和BglⅡ对基因组DNA进行全酶切,经0.4%琼脂糖凝胶电泳,特异回收9.5kb左右的DNA片段.将该片段与λEMBL3/BamHⅠ臂连接,构建成一个特殊的人基因组λ噬菌体文库(富集文库),效价为2×104.同时采用PCR方法及用引物Ⅰ:5′GGACAGGCTACATCAGGAAGAGG3′,引物Ⅱ:5′CTGCGTCTAATTGCAGTAGTTC3′,从人基因组DNA中扩增出一段含胰岛素基因的1.36kbDNA片段,做为放射性标记探针,对文库进行了噬菌斑原位杂交筛选,从1×104个噬菌斑中筛选到一个含人胰岛素基因组基因的阳性克隆,并进一步完成了亚克隆和该基因1732bpDNA序列的测定.结果该基因的1732bpDNA序列包括部分5′端和3′端与国外发表的人胰岛素α型等位基因的序列相同  相似文献   
93.
林奇  牛映斗 《人类学学报》1989,8(3):245-247
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。  相似文献   
94.
本文利用两株针对HAFP分子不同抗原决定簇的单克隆抗体,鉴定HAFP酶解片断的抗原抗体反应性质,并同完整HAFP分子进行比较。结果表明,酶解片断上失去了一株单克隆抗体所对应的分子部份,完整保留着另一株单克隆抗体所识别的抗原决定簇,从而证实HAFP分子某些抗原结构之间具有可分割性。  相似文献   
95.
In the highly active antiretroviral therapy (HAART) era, hepatocellular carcinoma (HCC) is arising as a common late complication of human immunodeficiency virus (HIV) infection, with a great impact on morbidity and mortality. Though HIV infection alone may not be sufficient to promote hepatocarcinogenesis, the complex interaction of HIV with hepatitis is a main aspect influencing HCC morbidity and mortality.Data about sorafenib effectiveness and safety in HIV-infected patients are limited, particularly for patients who are on HAART. However, in properly selected subgroups, outcomes may be comparable to those of HIV-uninfected patients. Scarce data are available for those other systemic treatments, either tyrosine kinase inhibitors, as well as immune checkpoint inhibitors (ICIs), which have been added to our therapeutic armamentarium. This review examines the influence of HIV infection on HCC development and natural history, summarizes main data on systemic therapies, offers some insight into possible mechanisms of T cell exhaustion and reversal of HIV latency with ICIs and issues about clinical trials enrollment. Nowadays, routine exclusion of HIV-infected patients from clinical trial participation is totally inappropriate, since it leaves a number of patients deprived of life-prolonging therapies.  相似文献   
96.
We have used [2-13C]d-glucose and carbon-13 nuclear magnetic resonance (NMR) spectroscopy to investigate metabolic fluxes through the major pathways of glucose metabolism in intact human erythrocytes and to determine the interactions among these pathways under conditions that perturb metabolism. Using the method described, we have been able to measure fluxes through the pentose phosphate pathway, phosphofructokinase, the 2,3-diphosphoglycerate bypass, and phosphoglycerate kinase, as well as glucose uptake, concurrently and in a single experiment. We have measured these fluxes in normal human erythrocytes under the following conditions: (1) fully oxygenated; (2) treated with methylene blue; and (3) deoxygenated. This method makes it possible to monitor various metabolic effects of stresses in normal and pathological states. Not only has 13C-NMR spectroscopy proved to be a useful method for measuring in vivo flux through the pentose phosphate pathway, but it has also provided additional information about the cycling of metabolites through the non-oxidative portion of the pentose phosphate pathway. Our evidence from experiments with [1-13C]-, [2-13C]-, and [3-13C]d-glucoses indicates that there is an observable reverse flux of fructose 6-phosphate through the reactions catalyzed by transketolase and transaldolase, even in the presence of a net flux through the pentose phosphate pathway.  相似文献   
97.
以人红细胞膜为材料,研究了甲基毒死蜱与膜上乙酰胆碱酯酶(AChE)的相互作用及其与膜脂的关系。结果显示,甲基毒死蜱对人红细胞膜AChE有明显的抑制作用,与膜温育30min,其半数抑制浓度约为0.10 mmol/L。动力学分析表明,其抑制作用为非竞争性。0.2%Triton X-100并不改变AChE对甲基毒死蜱的敏感性,亦即AChE上甲基毒死蜱的作用部位与其所处的脂质微环境无关。  相似文献   
98.
检测Mdrl基因表达水平可预测白血病化疗效果,用原位杂交的方法可检测Mdrl在单个细胞的表达水平。本文用Rt-PCR的方法获得了一段特异的cDNA片段,将其克隆到PGEM4Z载体中,经DNA序列分析证明与文献报道一致,采用地高辛素(DIG)RNA标记试剂盒制备反义RNA探针,已初步用于临床骨髓涂片标本的原位杂交检测。  相似文献   
99.
Reactive oxygen species (ROS) behave as second messengers in signal transduction for a series of receptor/ligand interactions. A major regulatory role is played by hydrogen peroxide (H2O2), more stable and able to freely diffuse through cell membranes. Copper–zinc superoxide dismutase (CuZn-SOD)-1 is a cytosolic enzyme involved in scavenging oxygen radicals to H2O2 and molecular oxygen, thus representing a major cytosolic source of peroxides. Previous studies suggested that superoxide anion and H2O2 generation are involved in T cell receptor (TCR)-dependent signaling. Here, we describe that antigen-dependent activation of human T lymphocytes significantly increased extracellular SOD-1 levels in lymphocyte cultures. This effect was accompanied by the synthesis of SOD-1-specific mRNA and by the induction of microvesicle SOD-1 secretion. It is of note that SOD-1 increased its concentration specifically in T cell population, while no significant changes were observed in the “non-T” cell counterpart. Moreover, confocal microscopy showed that antigen-dependent activation was able to modify SOD-1 intracellular localization in T cells. Indeed, was observed a clear SOD-1 recruitment by TCR clusters. The ROS scavenger N-acetylcysteine (NAC) inhibited this phenomenon. Further studies are needed to define whether SOD-1-dependent superoxide/peroxide balance is relevant for regulation of T cell activation, as well as in the functional cross talk between immune effectors.  相似文献   
100.
目的:测定云南肺癌患者人类白细胞抗原(human leukocyte antigen,HLA)-A、B、DRB1、DQB1等位基因出现频率,探讨HLA各等位基因位点与云南省肺癌发病易感性的相关性。方法:采用病例-对照相关分析方法,选取云南籍肺癌患者和健康个体各30例,应用序列特异性引物聚合酶链反应(polymerase chain reaction-sequence specific primer,PCR-SSP)对HLA-A、HLA-B、HLA-DRB1及HLA-DQB1等位基因频率进行测定,与正常组对比测算相对危险因子(relative risk,RR)。结果:肺癌组的HLA-A~*02频率为90.0%(A~*0201为主),B~*46频率为40.0%,DRB1~*15频率为40.0%,较对照组的43.30%、0%、10.0%明显升高(Pc0.05,RR1)。肺癌组的HLA-A~*31频率为3.30%,A~*33频率为6.70%,B~*27频率为3.30%,B~*52频率为6.70%,DRB1~*03频率为0%,DRB3~*01频率为60.0%,DQB1~*02频率为0%,DQB1~*06频率为0%,较对照组的23.30%、26.70%、26.70%、26.70%、23.30%、86.70%、23.30%、26.70%降低明显,(RR1,Pc0.05)。结论:云南肺癌易感性可能与HLA-A~*02的频率(90%)具有相关性;而HLA-A~*31、HLA-A~*33、HLA-B~*52、HLA-B~*27、HLA-DRB1-~*03、HLA-DRB3~*01、HLA-DQB1~*02及HLA-DQB1~*06在肺癌患者中的频率较低,在云南肺癌发病中可能具有遗传拮抗作用。  相似文献   
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