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Sertoli和Leydig细胞的相互作用及其PA/PAI-1表达的调节 Sertoli和Leydig细胞的相互作用及其PA/PAI-1表达的调节
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1995-08-10 DOI: 10.1360/ZB1995-25-8-852
刘以训 杜群 刘奎 周红明 胡召元, Du Qun Liu Kui Zhou Gong-Meng Hu Shao-Yuan Liu Si-Xun
{"title":"Sertoli和Leydig细胞的相互作用及其PA/PAI-1表达的调节","authors":"刘以训 杜群 刘奎 周红明 胡召元, Du Qun Liu Kui Zhou Gong-Meng Hu Shao-Yuan Liu Si-Xun","doi":"10.1360/ZB1995-25-8-852","DOIUrl":"https://doi.org/10.1360/ZB1995-25-8-852","url":null,"abstract":"用细胞培养,SDS-凝胶电泳,纤蛋白铺盖和反向纤蛋白自显影等技术研究了大鼠睾丸支持细胞(Sc)和间质细胞(Lc)的相互作用。实验结果表明,Sc产生两种纤溶酶原激活因子(PA),即组织型PA(tPA)和尿激酶型PA(uPA)及一种PA的抑制因子(PAI-1)。tPA及PAI-1的分泌受FSH,forskolin(FK)。双丁酰环腺苷酸(dbcAMP),GnRH及生长因子(EGF,FGF)的调节;但不受hCG和雄烯二酮(△~4)的影响;FSH也刺激Sc产生PAI-1。本项研究证明大鼠Sc能同时产生tPA,uPA和PAI-1;而Lc和Sc的相互作用是tPA和PAI-1表达的重要条件。","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"104 1","pages":"852-857"},"PeriodicalIF":0.0,"publicationDate":"1995-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87809737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
深海沉积中的几种“特殊”原生沉积构造 深海沉积中的几种“特殊”原生沉积构造
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1995-08-10 DOI: 10.1360/ZB1995-25-8-890
晋慧娟 李育慈, Li Hui-Juan
{"title":"深海沉积中的几种“特殊”原生沉积构造","authors":"晋慧娟 李育慈, Li Hui-Juan","doi":"10.1360/ZB1995-25-8-890","DOIUrl":"https://doi.org/10.1360/ZB1995-25-8-890","url":null,"abstract":"新疆准噶尔盆地周边海西造山带和西秦岭海西-印支造山带深海沉积中,发现了诸多长期以来被误认为仅形成于浅水环境的原生沉积构造,如:大型交错层理、各种小水流波痕、小型丘状交错层理、透镜状层理和韵律层理。文中对上述原生沉积构造的形态特征、形成环境和形成机制进行了系统研究。这些原生沉积构造可同时出现于深海、滨、浅海等环境中的事实表明,原生沉积构造特别是单一的原生沉积构造,并不能作为沉积环境解释的直接依据,重塑古环境必须重视各种相标志的综合解释。","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"160 1","pages":"890-897"},"PeriodicalIF":0.0,"publicationDate":"1995-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73367183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
CH 3 +H 2 O→CH 4 +OH的反应途径及动态学理论研究 CH 3 +H 2 O→CH 4 +OH的反应途径及动态学理论研究
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1995-08-10 DOI: 10.1360/ZB1995-25-8-816
刘若庄 马思渝, Liu Re-Peng Ma Sai-Yu
{"title":"CH 3 +H 2 O→CH 4 +OH的反应途径及动态学理论研究","authors":"刘若庄 马思渝, Liu Re-Peng Ma Sai-Yu","doi":"10.1360/ZB1995-25-8-816","DOIUrl":"https://doi.org/10.1360/ZB1995-25-8-816","url":null,"abstract":"用从头算方法计算了反应CH 3 +H 2 O→CH 4 +OH的反应途径、沿反应途径的动态学性质及正则变分过渡态理论的速率常数。结果表明,电子相关能对反应活化位垒影响较大,反应存在返回效应和隧道效应。","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"97 1","pages":"816-821"},"PeriodicalIF":0.0,"publicationDate":"1995-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80199634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Multiobjective optimization of neural network. 神经网络的多目标优化。
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1995-08-01
J Wang, W Lü
{"title":"Multiobjective optimization of neural network.","authors":"J Wang,&nbsp;W Lü","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A theoretical model of multiobjective optimization neural network (MONN) and a new learning algorithm are presented. Experiment results show their effectiveness and advantage.</p>","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"38 8","pages":"971-8"},"PeriodicalIF":0.0,"publicationDate":"1995-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19705368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Analysis of heterogeneity of gene products (interferon) expressed in yeast. 基因产物(干扰素)在酵母中表达的异质性分析。
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1995-08-01
H Wang, B Gao, P Chen, L Dong, Y Li
{"title":"Analysis of heterogeneity of gene products (interferon) expressed in yeast.","authors":"H Wang,&nbsp;B Gao,&nbsp;P Chen,&nbsp;L Dong,&nbsp;Y Li","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>FPLC, SDS-PAGE and Western blot techniques are used to analyse the heterogeneity of interferon alpha A (IFN-alpha A) expressed in yeast. The heterogeneity consists of (i) the presence of IFN polymer, (ii) partial processing of signal leader peptide and (iii) internal degradation. The reasons for heterogeneity of gene products in expression system of yeast are analysed. The methods of avoiding heterogeneity, such as depolymerization, adding inhibitors of protease to the culture supernatant, the oligonucleotide-directed deletion mutagenesis and improvements of fermentation, are discussed.</p>","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"38 8","pages":"954-62"},"PeriodicalIF":0.0,"publicationDate":"1995-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19705367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
与浓度相关的扩散系数 D t 的求取 与浓度相关的扩散系数 D t 的求取
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1995-07-10 DOI: 10.1360/ZB1995-25-7-704
郑禄彬陈国权蔡光宇王清遐 刘中民, Zheng Lu-Ban Chen Guo-Quan Ca Guang-Yu Wang Qing-Xia Liu Zhong-Min
{"title":"与浓度相关的扩散系数 D t 的求取","authors":"郑禄彬陈国权蔡光宇王清遐 刘中民, Zheng Lu-Ban Chen Guo-Quan Ca Guang-Yu Wang Qing-Xia Liu Zhong-Min","doi":"10.1360/ZB1995-25-7-704","DOIUrl":"https://doi.org/10.1360/ZB1995-25-7-704","url":null,"abstract":"在扩散系数为常数的扩散理论的基础上,引入不定函数 F t 描述与浓度相关的扩散过程,导出了利用吸附曲线求取不同时间扩散系数 F t 的公式并对 D t 和 D t 的物理意义进行了分析。 D t 不同于积分扩散系数和微分扩散系数,从扩散过程中 D t 随时间或扩散物质的量的变化可以得到更多的有关分子运动行为的信息。以分子筛吸附体系为例,验证了理论结果的正确性,并获得了C 6 —C 8 正构烷烃在ZSM-5分子筛两类不同孔道中的扩散系数数据。","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"37 1","pages":"704-709"},"PeriodicalIF":0.0,"publicationDate":"1995-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76457137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
通过O,O-亚苯基磷酰氯与α-氨基酸三甲基硅基衍生物的反应观察五配位磷 通过O,O-亚苯基磷酰氯与α-氨基酸三甲基硅基衍生物的反应观察五配位磷
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1995-07-10 DOI: 10.1360/ZB1995-25-7-683
王倩, 赵玉芬, 安逢龙, 毛应群, 王芹珠
{"title":"通过O,O-亚苯基磷酰氯与α-氨基酸三甲基硅基衍生物的反应观察五配位磷","authors":"王倩, 赵玉芬, 安逢龙, 毛应群, 王芹珠","doi":"10.1360/ZB1995-25-7-683","DOIUrl":"https://doi.org/10.1360/ZB1995-25-7-683","url":null,"abstract":"利用O,O-亚苯基磷酰氯与α-氨基酸三甲基硅基衍生物的反应观察到五配位的分子内磷酸-羧酸混酐化合物Ⅵ,发现这种结构的形成需要分子内胺基、羧基以及磷的协同参与,而且只限于α-氨基酸,从而证明N-磷酰氨基酸的自催化反应是通过分子内磷酸-羧酸混酐中间体Ⅱ来实现的,形成Ⅱ的速度决定了自催化反应活性的大小。","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"29 1","pages":"683-688"},"PeriodicalIF":0.0,"publicationDate":"1995-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74552432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Regulation of human clotting factor IX cDNA expression in transgenic mice. 人凝血因子IX cDNA在转基因小鼠中的表达调控。
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1995-07-01
Y Hu, X Qiu, J Xue, Z Liu
{"title":"Regulation of human clotting factor IX cDNA expression in transgenic mice.","authors":"Y Hu,&nbsp;X Qiu,&nbsp;J Xue,&nbsp;Z Liu","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>To study the expression of human clotting factor IX cDNA in transgenic mice, which is an essential work on gene therapy for hemophilia B, 3 recombinant constructions containing different lengths of human clotting factor IX cDNA have been introduced into the cultured cells. All of the recombinant constructions were found to be expressed well in vitro. They were then microinjected into the male pronuclei of the fertilized mouse eggs respectively for generating transgenic mice. Unfortunately, none of them was expressed in any transgenic mice. These results show that the expression of the human clotting factor IX cDNA in the transgenic mice can be determined by cis regulatory element(s). As compared with the results from other related works, it is suggested that the cis regulatory element(s) is resided in the 5'-end non-coding region.</p>","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"38 7","pages":"825-33"},"PeriodicalIF":0.0,"publicationDate":"1995-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18630254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
类Mannich反应合成N-对甲苯磺酰基-α-氨基膦酸二乙酯 类Mannich反应合成N-对甲苯磺酰基-α-氨基膦酸二乙酯
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1995-06-20 DOI: 10.1360/ZB1995-25-6-591
陈茹玉, 戴庆, 张殿坤, 杨秀凤
{"title":"类Mannich反应合成N-对甲苯磺酰基-α-氨基膦酸二乙酯","authors":"陈茹玉, 戴庆, 张殿坤, 杨秀凤","doi":"10.1360/ZB1995-25-6-591","DOIUrl":"https://doi.org/10.1360/ZB1995-25-6-591","url":null,"abstract":"以乙酰氯为溶剂,通过芳醛与对甲苯磺酰胺及亚磷酸二乙酯的类Mannich反应合成了N-对甲苯磺酰基-α-氨基膦酸二乙酯类化合物.研究了该反应的机理.对产物的构象进行了讨论,并得到了X-单晶衍射的证实,初步生物活性测定表明,产物中有些具有除草活性.","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"3 1","pages":"591-595"},"PeriodicalIF":0.0,"publicationDate":"1995-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82516106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
簇-表面类比:钯原子簇的从头算 簇-表面类比:钯原子簇的从头算
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1995-06-15 DOI: 10.1360/ZB1995-25-6-573
徐昕, 王南钦, 吕鑫, 陈明旦, 张乾二
{"title":"簇-表面类比:钯原子簇的从头算","authors":"徐昕, 王南钦, 吕鑫, 陈明旦, 张乾二","doi":"10.1360/ZB1995-25-6-573","DOIUrl":"https://doi.org/10.1360/ZB1995-25-6-573","url":null,"abstract":"提出了金属态原则.通过引入大块固体的自由电子理论,构造了金属态基组.以钯原子簇为例,分别采用原子态基组和金属态基组,按基态原则、最低自旋态原则和金属态原则进行了从头算研究.根据大块金属的电子组态、d带宽度、Fermi能级等物理性质,比较了各种计算方案的计算效果.结果表明:利用金属态原则,较小的簇就可以体现不少大块固体的性质.","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"252 1","pages":"573-578"},"PeriodicalIF":0.0,"publicationDate":"1995-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73246840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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