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Protein & Cell 2015年第7期6卷 541-545页

作者： Huiyue Zhou (1) (2. Hui Zhao (3. Jiayong Zheng (3. Yuan Gao (1) (2. Yanming Zhang (1) Fangqing Zhao (1) Jinfeng Wang (1) 1.Computational Genomics Lab Beijing Institutes of Life Science Chinese Academy of Sciences Beijing 100101 China 2.University of Chinese Academy of Sciences Beijing 100049 China 3.Wenzhou People’s Hospital Wenzhou 325000 China

Dear Editor,Clustered regularly interspaced short palindromic repeats （CRISPR）, which are widely present in prokaryotic genomes （Grissa et al., 2.07）, belong to a family of DNA sequences characterized as short direct repeats （DR） separated by spacers （Jansen et al., 2.02.. CRISPR and CRISPR-asso- ciated （cas） genes are involved in resistance against exogenous sequences, and recognition of infected bacte- riophages depends on the sequence similarity between spacers and targeted phage DNA segments （Barrangou et al., 2.07）. CRISPRs exhibited diversity in different microbial communities, and that may be the response to different phaqe infections （Tyson and Banfield, 2.08）.

关键词： Microbial Community Bacterial Community Periodontal Disease Chronic Periodontitis Cluster Regularly Interspaced Short Palindromic Repeat

Correlations between the ages of Alnus host species and the genetic diversity of associated endosymbiotic Frankia strains from nodules

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Science China(Life sciences) 2005年第z1期48卷 76-81页

作者： DAI Yumei, ZHANG Chenggang, XIONG Zhi & ZHANG Zhongze institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, China Graduate School of the chinese academy of sciences,{3., China School of Forest Resources, Southwest Forestry College, Kunming 6502.4, China 1. institute of Applied Ecology Chinese Academy of Sciences 110016 Shenyang China 2. Graduate School of the chinese academy of sciences 100039 Beijing China 3. School of Forest Resources Southwest Forestry College 650224 Kunming China

Nodule samples were collected from four alder species: Alnus nepalensis, A. sibirica, A. tinctoria and A. mandshurica growing in different environments on Gaoligong Mountains,Yunnan Province of Southwest China and on Changbai Mountains, Jilin Province of Northeast China. PCR-RFLP analysis of the IGS between nifD and nifK genes was directly applied to uncultured Frankia strains in the nodules. A total of 2. restriction patterns were obtained. The Frankia population in the nodules of A. nepalensis had the highest genetic diversity among all four Frankia populations; by contrast, the population in the nodules of A. mandshurica had the lowest degree of divergence; the ones in the nodules of A. sibirica and A. tinctoria were intermediate. A dendrogram, which was constructed based on the genetic distance between the restriction patterns, indicated that Frankia strains from A. sibirica and A. tinctoria had a close genetic relationship. Frankia strains from A. nepalensis might be the ancestor of Frankia strains infecting other Alnus species. From these results and the inference of the ages of Alnus host species, it is deduced that there was a co-evolution between Alnus and its microsymbiont Frankia in China.

关键词： Frankia, Alnus, genetic diversity, co-evolution.

Effects of the intramolecular hydrogen bond of taxoids on their interactions with cytochrome P450s

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Effects of the intramolecular hydrogen bond of taxoids on th...

一个降解染料的希瓦氏菌新种——中国希瓦氏菌

中国药理学会临床药理学专业委员会会议暨第十次全国临床药理学学术会议

作者： ZHANG Yan-yan~(1,2. LIU Yong~1 YANG Ling~1 1 Latboratory of Pharmaceutical Resource Discovery & Dalian institute of Chemical Physics,chinese {2. of {3.,NO.457 Zhongshan Road,Dalian 11602.3}Liaoning,China 2.Graduate School of chinese academy of sciences,beijing 100049,China

AIM:Previous studies identify that C7-OH epimers of taxoids are the thermodynamically more stable isomers due to the strong hydrogen bonding of the C7α-OH to the C4α- acetate acyl *** order to understand the effects of certain structure modification on taxoids’ interactions with human hepatic cytochromes P450 better,the present study attempts to clarify the identity of the CYPs involved in 7- epi-Taxol,7-epi-10-Deacetyl’-Taxol,and their corresipond- ing C7β-*** metabolism and the underlying mech- anisms are also to investigate. METHODS:LC/MS/MS was used to identify the struc- tures of various taxoids metabolites by human liver micro- *** were conducted with CYP isoform spe- cific inhibitors and recombinant human CYP isofonns to as- cribe individual reaction to a single CYP isoform. RESULTS:Two monohydroxylated metabolites(M-1 and M-2.of 7-epi-Taxol were detected by LC/MS,and C3. (M-1),C6(M-2.were proposed as the possible hydroxy- lation sites.7-epi-10-Deacetyl-Taxol was hydroxylated at C6 by human liver microsomes thus making M-3.as the unique primary *** inhibition studies and assays with recombinant human CYPs indicated that C3. (M-1)was generated predominantly by CYP3.4 and C6 (M-2.M-3.by *** with the formation of C6-OH-majorepi-Taxol decreased significantlympounds among all chemotherapeutic drugs,Paclitaxel,the K for C6-hydroxylation of 7-epi-Taxol decreased significantly(13.versus 3.mol/L,8.5 versus 1.7μmol/L)by human liver microsomes and recombinant human ***, the overall metabolism of 7-epi-10-Deacetyl-Taxol in- creased to 2.% in contrast with the low biotransformation rate of 10-deacetyl-Taxol(less than 0.8%). CONCLUSION:These findings suggest the distinct 3. conformation change of taxoids caused by the intromolecu- lar hydrogen bonding may attribute a major role in the sub- strate recognition by CYP2.8 and lead C-6 of taxoids more accessible to the active site.

关键词： Paclitaxel 7-epi-Taxol 7-epi-10-deacetyl-Taxol chiral metabolism cytochrome P450

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微生物学报 2004年第5期44卷 561-566页

作者：许玫英郭俊钟小燕曹渭孙国萍岑英华广东省微生物研究所

从细胞形态、生理生化特性和 16SrRNA基因和gyrB基因序列同源性分析等方面对一株广谱高效染料降解菌D14进行了鉴定。菌株D14的细胞壁革兰氏染色为阴性 ,细胞为杆状 ,大小为 0 6 μm～ 1 0 μm× 1 0 μm～ 4 0 μm ,周身纤毛 ,极生单... 详细信息

从细胞形态、生理生化特性和 16SrRNA基因和gyrB基因序列同源性分析等方面对一株广谱高效染料降解菌D14进行了鉴定。菌株D14的细胞壁革兰氏染色为阴性 ,细胞为杆状 ,大小为 0 6 μm～ 1 0 μm× 1 0 μm～ 4 0 μm ,周身纤毛 ,极生单鞭毛 ,其生长pH范围为pH 7 0～ 10 0 ,最适生长pH为 8 0 ,生长温度范围为 4℃～ 4 0℃ ,最适生长温度为 2.0℃～ 3.℃。该菌株具有还原三价铁 ,液化明胶、Tween 4 0和Tween 80 ,产生H2.S的能力。在乳酸钠存在的条件下 ,能还原硝酸盐、亚硝酸盐、铁氧化物和硫代硫酸钠。可利用D_半乳糖、D_葡萄糖、蔗糖、丙酸钠、L_亮氨酸等多种有机物为碳源。BIOLOG细菌自动鉴定系统鉴定结果表明该菌株应归属于希瓦菌属。 16SrDNA和gyrB基因序列分析结果表明 ,菌株D14与其亲缘关系最近的菌株ShewanellaputrefacienATCC80 71T的 16SrDNA序列相似值为97% (小于 97 7% ) ,gyrB基因序列相似值为 87% (小于 90 % )。菌体所含有的主要脂肪酸为iso_15 :0 ,16 :1ω7c ,15 :0和 16 :0 ,DNA中 (G +C)mol%含量为 4 9 3.结合菌株D14的生理生化特征和分子生物学特性 ,将菌株定为希瓦氏菌属的一个新种 ,命名为中国希瓦氏菌 (Shewanellacinica)D14 T。

关键词：希瓦氏菌属中国希瓦氏菌 16S rDNA gyrB基因

利用mRNA荧光差异显示技术规模化筛选棉纤维特异表达基因

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生物工程学报 2004年第1期20卷 39-42页

作者：孙杰李园莉汪若海夏桂先中国科学院微生物研究所北京100080 中国农业科学院棉花研究所安阳455112

以陆地棉 (GossypiumhirsutumL .)品种TM 1开花后 9d、2.1d、2.7d三个不同发育时期的棉花纤维为材料 ,利用mRNA荧光差异显示 (FDD)技术 ,筛选到 10 9个差异显示的cDNA片段。在此基础上 ,结合两轮反Northern杂交筛选和Northern杂交分析 ... 详细信息

以陆地棉 (GossypiumhirsutumL .)品种TM 1开花后 9d、2.1d、2.7d三个不同发育时期的棉花纤维为材料 ,利用mRNA荧光差异显示 (FDD)技术 ,筛选到 10 9个差异显示的cDNA片段。在此基础上 ,结合两轮反Northern杂交筛选和Northern杂交分析 ,获得了多个仅在棉花纤维细胞中特异表达或在纤维中优先表达基因的cDNA片段 ,序列测定和数据库搜索分析表明 ,这些cDNA片段中的多数还未有报道。本工作为克隆上述基因的全长cDNA ,并进一步研究它们在棉纤维发育中的功能奠定了基础。

关键词：棉花纤维特异表达基因荧光差异显示克隆

CaO-超细高岭土复合固硫剂固硫动力学研究

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燃料化学学报 2004年第4期32卷 424-428页

作者：刘金权武增华王立新清华大学化学系深圳市宝安科技局深圳518101

利用高岭土的加工产品超细高岭土,制备了CaO 超细高岭土复合固硫剂,用热分析法研究其固硫性能和特征,并用等效粒子模型对该固硫剂固硫反应的动力学过程进行模拟和计算,得到了固硫反应的动力学参数。研究表明,CaO 超细高岭土复合固硫剂... 详细信息

利用高岭土的加工产品超细高岭土,制备了CaO 超细高岭土复合固硫剂,用热分析法研究其固硫性能和特征,并用等效粒子模型对该固硫剂固硫反应的动力学过程进行模拟和计算,得到了固硫反应的动力学参数。研究表明,CaO 超细高岭土复合固硫剂有着较好的固硫率,特别是高于1000℃时在固硫反应后期的产物层扩散控制阶段呈现很好的固硫率增长,1009℃下固硫率较CaO提高达2.%。

关键词：复合固硫剂 CaO-超细高岭土固硫反应动力学

Band gap anomaly and topological properties in lead chalcogenides

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chinese Physics B 2016年第3期25卷 27-34页

作者：聂思敏许霄琰徐刚方忠 beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences Beijing 1O0190 China Collaborative Innovation Center of Quantum Matter Beijing 100084 China

Band gap anomaly is a well-known issue in lead chalcogenides PbX （X = S, Se, Te, Po）. Combining ab initio calculations and tight-binding （TB） method, we have studied the band evolution in PbX, and found that the band gap anomaly in PbTe is mainly related to the high on-site energy of Te 5s orbital and the large s-p hopping originated from the irregular extended distribution of Te 5s electrons. Furthermore, our calculations show that PbPo is an indirect band gap （6.5 meV） semiconductor with band inversion at L point, which clearly indicates that PbPo is a topological crystalline insulator （TCI）. The calculated mirror Chern number and surface states double confirm this conclusion.

关键词： band gap anomaly lead chalcogenides indirect band gap semiconductor topological crystallineinsulator

Maximum Principle for the Optimal Control of an Ablation-Transpiration Cooling System with Free Final Time

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Infectious Disease Surveillance in China

第二十四届中国控制会议

作者： Bing Sun~(1,2., Baozhu Guo~1 ~1institute of Systems Science, academy of Mathematics and System {2., Academia Sinica, {3. 100080, China ~2.raduate School of the chinese academy of sciences, {3. 100049, China

＜正＞ This paper is concerned with the optimal control problem of an ablation-transpiration cooling control system with Stefan-Signorini boundary condition. The Pontryagin’s maximum principle of the system is presen... 详细信息

关键词： Ablation-transpiration Stefan-Signorini problem optimal control(OC) Pontryagin’s maximum principle Dubovitskii-Milyutin approach.

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Biomedical and Environmental sciences 1998年第1期11卷 31-37页

作者： ZENG GUANG ZHANG JING-KUN ROU KE-MING, XU CHANG CHENG YING-KAI AND QI GUO-MING(The institute of Epidemiology and Microbiology, chinese {2. ofPreventive Medicine, {3. 100050, China) institute of Epidemiology and Microbiology Chinese Academy of Preventive Medicine Beijing China.

A national system of infectious disease surveillance was established in 1959 in *** it consists of three subunits, namely, national disease reporting system (NDRS), nationwide disease surveillance points (DSPs), and surveillance network for specific infectious diseases. There are 3. notifiable infectious diseases, which are divided into Classes A, B, and C. The functions of the surveillance include explaining the natural history of infectious diseases, describing the distribution of case occurrence, triggering disease-control effort, monitoring epidemic of infectious diseases during natural disasters, predicting and controlling epidemics and providing the base of policy adjustment.

关键词： Infectious Disease Surveillance in China

Maternal Smad3.Deficiency Compromises Decidualization in Mice

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Maternal Smad3 Deficiency Compromises Decidualization in Mic...