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计算机自动结构解析专家系统研究——ESESOC-II结构产生器 计算机自动结构解析专家系统研究——ESESOC-II结构产生器
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1994-10-10 DOI: 10.1360/ZB1994-24-10-1014
胡昌玉, 许禄
{"title":"计算机自动结构解析专家系统研究——ESESOC-II结构产生器","authors":"胡昌玉, 许禄","doi":"10.1360/ZB1994-24-10-1014","DOIUrl":"https://doi.org/10.1360/ZB1994-24-10-1014","url":null,"abstract":"ESESOC-Ⅱ是一个用于含O,N,P,S及卤素等多种杂原子的有机化合物结构自动解析专家系统.它由3个部分组成:数据分析,结构产生器,结构验证。结构产生器是系统的核心部分,它从分子出发,穷举生成结构基元集和结构片断集,最后对接成穷举的、非冗余候选结构。文中详细介绍了结构产生器的结构生成算法。","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"197 1","pages":"1014-1022"},"PeriodicalIF":0.0,"publicationDate":"1994-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77649490","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
Protein crystal growth in microgravity. 微重力下蛋白质晶体的生长。
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1994-10-01
R C Bi, L L Gui, K Shi, Y P Wang, S Z Chen, Q Han, Y L Hu, F L Shen, X T Niu, Z Q Hua
{"title":"Protein crystal growth in microgravity.","authors":"R C Bi,&nbsp;L L Gui,&nbsp;K Shi,&nbsp;Y P Wang,&nbsp;S Z Chen,&nbsp;Q Han,&nbsp;Y L Hu,&nbsp;F L Shen,&nbsp;X T Niu,&nbsp;Z Q Hua","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Protein crystal growth is quite important for the determination of protein structures which are essential to the understanding of life at molecular level as well as to the development of molecular biotechnology. The microgravity environment of space is an ideal place to study the complicated protein crystallization and to grow good-quality protein crystals. A number of crystal-growth experiments of 10 different proteins were carried out in August, 1992 on the Chinese re-entry satellite FSW-2 in space using a tube crystallization equipment made in China. A total of 25 samples from 6 proteins produced crystals, and the effects of microgravity on protein crystal growth were observed, especially for an acidic phospholipase A2 and henegg-white lysozyme which gave better crystals in space than earth-grown crystals in ground control experiments. The results have shown that the microgravity in space favors the improvement of the size, perfection, morphology and internal order of the grown protein crystals.</p>","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"37 10","pages":"1185-91"},"PeriodicalIF":0.0,"publicationDate":"1994-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18864458","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
Connection ensemble model of local neural circuits. 局部神经回路的连接集成模型。
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1994-10-01
G Z Yao, M Wang, L M Tao
{"title":"Connection ensemble model of local neural circuits.","authors":"G Z Yao,&nbsp;M Wang,&nbsp;L M Tao","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A connection ensemble model (CEM) of local neural circuits in central nervous system (CNS) is proposed in this work. Neuronal interactions are investigated at two levels, i.e. the synaptic connection between single neurons and the macro-connections between different neuronal groups. The efficacy of macro-connection is quantitatively determined by the efficacies of constituent synapses, and is asymptotically stable. This model provides a reasonable description for the functional invariance of local neural circuits with structural diversities, which is a widely observed fact in neurobiology. It is expected that the works in CEM model would enrich the current research in neural dynamics.</p>","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"37 10","pages":"1198-1207"},"PeriodicalIF":0.0,"publicationDate":"1994-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18864459","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
A new genetically engineered vaccine for animal growth promotion. 一种新的促进动物生长的基因工程疫苗。
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1994-10-01
W Z Xu, N X Du, G D Li, Y Wang, Z P Li
{"title":"A new genetically engineered vaccine for animal growth promotion.","authors":"W Z Xu,&nbsp;N X Du,&nbsp;G D Li,&nbsp;Y Wang,&nbsp;Z P Li","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The chemically synthesized somatostatin (ss) gene was fused in phase with the 3'-end of hepatitis B virus surface antigen (HBsAg) gene. The fusion gene HBs/ss was then recombined into the genome of vaccinia virus. This recombinant virus (vv-HBs/ss) can express hybrid HBsAg/ss particles which present as determinants on their surfaces, thereby bearing a good immunogenicity. This new strategical vaccine of ss can elicit the production of antibody capable of neutralizing ss in the plasma, and consequently enhance the growth of animals.</p>","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"37 10","pages":"1234-41"},"PeriodicalIF":0.0,"publicationDate":"1994-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18864460","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
甾体植物生长调节剂的研究——XXX.新23-羧基油菜甾体的立体选择性合成 甾体植物生长调节剂的研究——XXX.新23-羧基油菜甾体的立体选择性合成
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1994-09-10 DOI: 10.1360/ZB1994-24-9-897
周维善, 李静, 黄良富
{"title":"甾体植物生长调节剂的研究——XXX.新23-羧基油菜甾体的立体选择性合成","authors":"周维善, 李静, 黄良富","doi":"10.1360/ZB1994-24-9-897","DOIUrl":"https://doi.org/10.1360/ZB1994-24-9-897","url":null,"abstract":"从猪去氧胆酸立体选择性合成新的23-羧基油菜甾体6和7。关键步骤是11和14的α,β-不饱和酯侧链经OsO 4 催化不对称双羟化而高立体选择性地引入天然(22R,23S)-22,23-双羟基。","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"1 1","pages":"897-903"},"PeriodicalIF":0.0,"publicationDate":"1994-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74388885","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
单链抗体PS-9的基因克隆、表达和免疫特性鉴定 单链抗体PS-9的基因克隆、表达和免疫特性鉴定
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1994-09-10 DOI: 10.1360/ZB1994-24-9-937
阎锡蕴, 田波, 李力, 袁玫
{"title":"单链抗体PS-9的基因克隆、表达和免疫特性鉴定","authors":"阎锡蕴, 田波, 李力, 袁玫","doi":"10.1360/ZB1994-24-9-937","DOIUrl":"https://doi.org/10.1360/ZB1994-24-9-937","url":null,"abstract":"成功地构建了鼠抗人胰腺癌单克隆抗体PS-9的单链抗体可变区基因(V H -linker-V L ),并将该基因克隆到噬菌体表达载体pCANTAB5的外壳蛋白g3p基因中,使单链抗体以融合蛋白的形式表达在噬菌体的表面。免疫学鉴定结果表明,这种噬菌体抗体仍保留着亲代抗体的免疫特性,能与人粘液细胞癌LS-174-T细胞表面抗原特异结合。这项研究结果有助于鼠源性单克隆抗体的临床应用以及肿瘤导向诊断和治疗。","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"19 1","pages":"937-941"},"PeriodicalIF":0.0,"publicationDate":"1994-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83716035","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
Expression of human beta E-globin gene with erythroid enhancer in transgenic mice. 带红细胞增强子的人β - e -珠蛋白基因在转基因小鼠中的表达。
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1994-09-01
Q H Liu, D P Liu, Y Z Ding, Q Z Wei, P C Jia, S S Chen, Z Q Liang
{"title":"Expression of human beta E-globin gene with erythroid enhancer in transgenic mice.","authors":"Q H Liu,&nbsp;D P Liu,&nbsp;Y Z Ding,&nbsp;Q Z Wei,&nbsp;P C Jia,&nbsp;S S Chen,&nbsp;Z Q Liang","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The human beta E-globin gene from HbE (beta 26 Glu-->Lys, G-->A) homozygote, a common hemoglobinopathy in China, was injected into the pronuclei of fertilized mouse eggs to prepare transgenic mice. A transgenic mouse bearing 16 copies of construct 5'.HS2 beta E has characteristics of typical transgenic mice. It has been verified that the presence of erythroid enhancer 5'HS2 is necessary for the high level expression of human beta E-globin gene in transgenic mice, indicating that the cis-element 5'HS2 is effective for abnormal beta-globin gene as well. Although the expression level of beta-globin gene was copy number-dependent as reported in previous studies, the average expression level per gene copy (12.1%) in transgenic mice bearing many copies of 5'HS2 beta E (16 copies) was significantly lower than that (79.7%) in transgenic mice bearing fewer copies of the gene (2 copies). The possible mechanisms for this decrease of expression are discussed. Novel hemoglobin tetramers which presumably consist of human beta E-globin chains and mouse endogenous alpha-globin chains have been assembled in transgenic mice.</p>","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"37 9","pages":"1113-8"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18988843","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
Molecular cloning and expression of human interleukin-6 in insect cells. 人白细胞介素-6在昆虫细胞中的分子克隆及表达。
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1994-09-01
C W Zhao, J X Wang, D H Xiao, X K Ma
{"title":"Molecular cloning and expression of human interleukin-6 in insect cells.","authors":"C W Zhao,&nbsp;J X Wang,&nbsp;D H Xiao,&nbsp;X K Ma","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>670-bp hIL-6 cDNA fragments have been amplified by polymerase chain reaction (PCR) using recombinant plasmid pBMIL-6A as templates and two synthetic oligonucleotides containing the optimized translation initiation sequence and restriction sites suitable for cloning as primers. The amplified IL-6 cDNA fragments have then been recombined with a non-fusion expression baculovirus vector pVL1393. The resultant recombinant plasmid pVL. IL-6 together with wtAcMNPV DNAs were transferred into cultured lepidopteran insect cells (Sf9) by calcium phosphate coprecipitation procedure. The recombinant baculoviruses were formed by homologous recombination in vivo between pVL. IL-6 and wtAcMNPV DNAs, screened for plaque assay, and identified by means of dot blotting hybridization. The expressed rhIL-6 was secreted into the culture medium, and its bioactivity was measured through half-maximum H-TdR incorporation into IL-6-dependent cells 7TD1. As a result, the supernatant collected from recombinant baculovirus rAc. IL-6-infected Sf9 cells showed IL-6 activity of 10(6) U/mL. The expression level of rhIL-6 of the supernatant determined by IL-6 ELISA quantitation kit was 1 microgram/mL.</p>","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"37 9","pages":"1073-81"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18988842","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
异氰酸(HNCO)自旋禁阻脱羰反应中的旋-轨偶合效应 异氰酸(HNCO)自旋禁阻脱羰反应中的旋-轨偶合效应
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1994-08-10 DOI: 10.1360/ZB1994-24-8-793
刘若庄 方维海, Liu Wei-hai
{"title":"异氰酸(HNCO)自旋禁阻脱羰反应中的旋-轨偶合效应","authors":"刘若庄 方维海, Liu Wei-hai","doi":"10.1360/ZB1994-24-8-793","DOIUrl":"https://doi.org/10.1360/ZB1994-24-8-793","url":null,"abstract":"用自洽场从头算方法确定了异氰酸自旋禁阻脱羰反应单、三态势能面的零级近似能量极小交叉点(在MRSDCI/6-31G的水平上)。首次将分子中原子近似与有效单电子旋-轨偶合算符结合,在自洽场从头算CI的基础上得到单、三态的旋-轨偶合矩阵元,并用微扰方法据此确定单、三态波函数的混合系数,从而证明在零级近似能量极小交叉点邻域内,必伴随有单、三态的混合,异氰酸脱羰反应过程为:单态(反应物)→混合态(能量极小交叉点邻域)→三态(产物)。将零极近似能量极小交叉点视为反应过渡态,由此算得反应的活化势垒为354.163kJ·mol~(-1),这与实验结果极好的一致。","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"1 1","pages":"793-797"},"PeriodicalIF":0.0,"publicationDate":"1994-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88476495","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
BaFBr∶Eu 2+ 的高温热释发光 BaFBr∶Eu 2+ 的高温热释发光
Science in China. Series B, Chemistry, life sciences & earth sciences Pub Date : 1994-08-10 DOI: 10.1360/ZB1994-24-8-810
陈伟, 苏勉曾
{"title":"BaFBr∶Eu 2+ 的高温热释发光","authors":"陈伟, 苏勉曾","doi":"10.1360/ZB1994-24-8-810","DOIUrl":"https://doi.org/10.1360/ZB1994-24-8-810","url":null,"abstract":"报道了BaFCl:Eu 2+ 晶体的高温热释发光(RT-773K)。发现了3个新的高温热释峰。通过研究发现这3个高温热释峰是由晶体中 F 心的缔合中心 F 2 , F 3 和 F 4 心产生的。还给出了各热释峰的特征参数。并指出BaFCl:Eu 2+ 热释发光过程的复杂性,伴随热释发光过程中还有电子的转移以及缔合中心的分解。","PeriodicalId":21648,"journal":{"name":"Science in China. Series B, Chemistry, life sciences & earth sciences","volume":"1 1","pages":"810-815"},"PeriodicalIF":0.0,"publicationDate":"1994-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89521520","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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