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91.
Ⅰ型纤溶酶原激活物抑制剂(PAI-1)是一种Mr为50×103的单链糖蛋白,有379个氨基酸残基,3个N型糖基化位点。构建PAI-1糖基化突变体,以便研究糖链的功能。用寡核苷酸定位突变技术将3个糖基化位点209,265,329位进行突变,把3个糖基化位点都发生了突变的PAI-1cDNA组装到真核表达载体pSV2中,得到真核表达质粒pZH-p1-M3E;在二氢叶酸还原酶缺陷型中国仓鼠卵巢细胞(CHOdhfr-)中进行短暂表达,用发色底物法和夹心ELISA方法检测培养液中PAI-1的活性和含量。结果:糖基化位点突变的PAI-1能在CHO细胞中表达,但表达水平及活性较低。非糖基化PAI-1的活性和抗原分别为4.34IU/ml和3.15μg/L结论:用寡核苷酸定位突变方法获得了PAI-1糖基化突变体,并且在CHO细胞中得到表达。  相似文献   
92.
Laryngeal cancer represents an important cause of cancer in France, and the individual effects of alcohol and tobacco on this cancer site are well known. However the problem of the interaction between these agents is less extensively documented, and the role of the high consumptions of alcohol has not been studied frequently. A case-control analysis was undertaken to investigate the joint effect of alcohol and tobacco by comparing 197 glottic and 214 supraglottic cancer cases to 4135 controls representative of the French general population. Heavy drinkers were available from the two groups of cases, the highest alcohol category being equivalent to a consumption of more than 2 litres of wine per day. The relative risks estimated for heavy drinkers and smokers were high, and the results indicated an even stronger effect of alcohol drinking and tobacco smoking on the upper part of the laryngeal region. Additive and multiplicative models were fitted to the data. The multiplicative hypothesis was found to be the most appropriate, implying that the risks associated with alcohol and tobacco multiply when the exposures occur simultaneously. The public health implications of this result and the contribution of heavy drinkers and smokers to the frequency of upper respiratory and digestive tract cancers are discussed.  相似文献   
93.
本文对夹竹桃甙抑制Na~+、K~+-ATP酶的动力学作了探讨,并与乌本甙的作用进行了比较。结果表明:夹竹桃甙抑制Na~+、K~+-ATP酶,在Na~+、K~+浓度改变对均为非竞争性抑制,Na~+/K~+比例6:1时,为混合性抑制,而ATP对夹竹桃甙的作用几无影响。  相似文献   
94.
This is first report about the simultaneous over-expression of both Insulin-like growth factor (IGF-II) and its receptor (IGF-II R) at mRNA level in human primary hepatic Cancer (PHC). In 10 PHC samples from China, IGF-II and IGF-II R were both over-expressed, whereas only a background signal was detected in normal liver. In 5 pairs of PHC and its non-tumorous adjacent liver tissues from South Africa, IGF-II and IGF-II R were also over-expressed in PHC. mRNA expression of IGF-II in all 5 cases and IGF-II R in 4 of 5 cases were higher in cancer than non-tumorous adjacent liver tissues. These results strongly implicate that an autocrine and/or paracrine mechanism might be involved in formation and progression of PHC.  相似文献   
95.
A tissue equivalent phantom was used in the study and absored x-ray doses.It measuring for some important organs of head and neck by four routive sialography methods (panoramic conventional x-ray radioagraphy,tomography,fluoroscope,CT) and also the X-ray absorbed doses of thyroid and len when lead containing loop and spectacles of head containing glass were used for prevention.All the data were processed statistically and a compartive study of absorbed x-ray doses of four sialography methods:Doses of submandibular gland were higher in CT,tomography and fluoroscope among them,CT was the highest indicating that it was superior to other methods for accurately locating that it was superior to other methods for accurately locating the within-gland tumor.Fluoroscope will be use more frequently in clinic,because it can observe the living gland panoramic and normal radiography can be used routinely because they had the minimum doses in measured organs.2.The absorbed x-ray doses of len and thyroid decreased by 93%-% when prevention was taken in CT or fluoroscope,65%-85% doses was decreased in normal radiography or panoramic with prevention.  相似文献   
96.
煤烟型大气污染对儿童肺功能的影响   总被引:4,自引:1,他引:3  
为观察煤烟型大气污染对儿童健康的影响 ,选择了太原市 3个污染程度不同地区的 45 0名儿童进行肺功能测试和问卷调查。研究结果显示 ,儿童呼吸功能表现为重度污染区 <中度污染区 <相对清洁区 ;肺通气功能阻塞性异常率表现为重度污染区 >中度污染区 >相对清洁区 ;Logistic回归分析发现肺通气功能阻塞性异常率与小学生家庭的取暖方式、厨房和卧室是否分开以及污染物的水平有关 ;多元线性回归分析显示重度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 65 80ml、119 2 7ml,中度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 5 7 2 8ml和 114 2 9ml;Ln(SO2 )每升高一个单位 ,FVC和FEF5 0分别减少69 10ml和 119 79ml,Ln(PM1 0 )每升高一个单位 ,FVC、FEF5 0等分别减少了 193 5 0ml和 171 69ml。结果提示 ,太原市煤烟型大气污染对儿童呼吸系统产生了危害。  相似文献   
97.
目的 观察东莨菪碱对大鼠下丘脑室核精氨酸升压素的影响。方法 以不同浓度Scop推挽灌流大鼠下丘脑室旁核 结果 扣留出液中精氨酸升压素含量随推挽时间延长而增多。结论Scop可促进PVN释放内源性AVP,这对了解Scop抗休克的机理有重大的意义。  相似文献   
98.
目的 评价第三代CT定量诊断胆囊结石的准确率及敏感性.方法 120例胆囊结石的病人在使用第三代CT检查后7天内施行胆囊切除手术,术后剖开胆囊,进行结石计数和最大结石的最大径线测量.结果 120例胆囊结石患者,其中87例有确切结石计数和测量结果(72.5%);33例CT检查未发现胆囊结石(27.5%).CT图像中显示的胆囊结石的数目:均数±标准差=3±15个;范围为2~82个与手术发现的数目:均数±标准差=68±316个;范围为2~1326个,两者比较具有显著性差异(P<0.001).CT图像发现的胆囊内最大结石的最大径线值:均数±标准差=1.08±1.06cm,范围为0~2.4cm;与手术测量值均数±标准=1.68±0.14cm范围为0.67~3.1cm,两者比较有显著性差异(P<0.001).结论 用第三代CT进行胆囊结石的定量诊断不够准确,敏感性也有不足.  相似文献   
99.
The effect of (+/-)-, (+)- and (-)-gossypol on testicular lactate dehydrogenase-X (LDH-X) was studied in vitro and in vivo. It was found that racemic gossypol and the two optical enantiomers had similar inhibitory effects on rat testicular LDH-X in vitro. However, neither racemic gossypol nor the enantiomers exhibited an inhibitory effect on testicular LDH-X in vivo. It is concluded that inhibition of testicular LDH-X is not likely to be the mechanism of the antifertility action of gossypol. The inhibition of testicular LDH-X in vitro by all three preparations of gossypol is probably non-specific.  相似文献   
100.
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