检索结果-南通市图书馆

Isolation, characterization and functional analysis of a cdc48 homologue from tobacco BY-2 cells

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Progress in Natural science:Materials International 2007年第2期17卷 156-162页

作者： CHEN Zhiling, YU Yi, LIU Lina and XIA Guixian ( college of life science, Capital normal university, Beijing 100037, china Institute of Microbiology, Chinese Academy of sciences, Beijing 100080, china) [a]college of life science Capital Normal University Beijing China [b]Institute of Microbiology Chinese Academy of Sciences Beijing China

The fission yeast Schizosaccharomyces pombe was used to identify genes from tobacco BY-2 cells that may play roles in cell cycle regulation. A cDNA encoding a protein homologous to the yeast CDC48 was isolated and the gene was designated as NtCDC48 . The cDNA contains an open reading frame coding for a predicted protein of 808 amino acids which comprises of two typical ATPase modules (aa 245-374 and aa 518-646) . Overexpression of NtCDC48 in tobacco BY-2 cells led to an increase in the mitotic index as well as to the formation of diffused mitotic spindles. NtCDC48-GFP fusion proteins are distributed ubiquitously through Gl to M phases, yet their subcellular localization varied regularly along with the cell cycle progression. These results indicate that NtCDC48 may play an important role in the regulation of cell cycle in BY-2 cells.

关键词： tobacco BY-2 suspension cells NtCDC48 spindle cell cycle.

Nuclear Magnetic Resonance Studies on Huwentoxin-Ⅺ from the Chinese Bird Spider Ornithoctonus huwena:15N Labeling and Sequence-specific 1H,15N Nuclear Magnetic Resonance Assignments

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Biochimica et Biophysica Sinica 2006年第7期 457-466页

作者： Kuan PENG~1 Ying LIN~1 Song-Ping LIANG~(1,2*) 1 college of life science,Peking university,Beijing 100871,china 2 college of life science,Hunan normal university,Changsha 410081,china

Huwentoxin-XI purified from the Chinese bird spider Ornithoctonus huwena is a toxin withboth antiprotease activity and potassium channel blocking *** determine its solution structure,huwentoxin-Ⅺ was expressed in a yeast eukaryotic expression system and studied by ***15N labelingstrategy was used to facilitate the process of resonance *** nearly complete sequence-specificassignments of proton and nitrogen resonances were obtained by analyzing a series of two-dimensional（2D）and three-dimensional（3D）spectra,including DQF-COSY,TOCSY,NOESY,15N-1H HSQC,15N-1H HNHA,15N-1H HNHB,15N-1H TOCSY-HSQC and15N-1H NOESY-HSQC *** structure analysis ofhuwentoxin-Ⅺ showed that it mainly contains an N-terminal 310-helix from Thr3 to Arg5 and a C-terminalα-helix from Gln45 to Cys52,plus a triple-stranded antiparallel β-sheet of Glul 8-Asn23,Thr26-Ile31 *** studies provide a solid basis for the final structure determination of huwentoxin-Ⅺ.

关键词： huwentoxin-XI toxin nuclear magnetic resonance 15N labeling sequence-specific assignment

Application of Genetic Programming in Predicting Infinite Dilution Activity Coefficients of Organic Compounds in Water

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2003年第9期14卷 987-990页

作者： Yi Lin CAO, Huan Ying LI college of chemistry and Environmental science, Henan normal university, Xinxiang 453002 college of chemistry and Environmental science Henan Normal University

In this paper, we calculated 37 structural descriptors of 174 organic compounds. The 154 molecules were used to derive quantitative structure - infinite dilution activity confficient relationship by genetic programming, the other 20 compounds were used to test the model. The result showed that molecular partition property and three-dimensional structural descriptors have significant influence on the infinite dilution activity coefficients.

关键词： Infinite dilution activity coefficients genetic programming.

Cyclometalated platinum(Ⅱ) complexes with sterically bulky camphor-derived groups as β-diketonate ancillary ligand:a new route to efficiently reducing π-π interactions and Pt-Pt interactions

在线全文

学校读者我要写书评

暂无评论

science china chemistry 2010年第1期53卷 167-172页

作者： LUO KaiJun,XIE Yu,XU LingLing,WANG JiangWei,ZHANG LiFang & ZHAO KeQing college of chemistry and Materials science,Sichuan normal university,Chengdu 610068,china college of chemistry and Materials science Sichuan Normal University Chengdu China

A new series of mono-cyclometalated square planar platinum(Ⅱ) complexes have been synthesized and the single-crystal X-ray structures of complex 1 and 2 have been *** complexes have the general formula ppyPt(O^O),where ppy is 2-phenylpyridyl,and O^O is β-diketonate ancillary ligands with the acyl substituent group in position 3 of(D)-(+)-***,like the many Pt(Ⅱ) complexes with square-planar geometry,these complexes have plane stacking modes in crystal structure,the sterically bulky camphor-derived groups compel extensive slipping of the molecular stacking planes,resulting in the negligible overlapping of the aromatic ring fragments between molecules and the considerable Pt-Pt *** resolved spectra and a little shifted emission in solid state of complexes show that there is significant reduction of π-π interactions and Pt-Pt interactions,and suggest these complexes may be good candidates for doped phosphorescent organic light emitting diodes(PhOLEDs) and even for nondoped PhOLEDs.

关键词： sterically bulky camphor derivatives crystal structure π-π interactions cyclometalated Pt(Ⅱ) complexes

Sequencing and analysis of the complete mitochondrial DNA of Russell's snapper (***)

在线全文

学校读者我要写书评

暂无评论

Progress in Natural science:Materials International 2008年第10期18卷 1233-1238页

作者： Yusong Guo~(a,1) Zhongduo Wang~(a,b,1) Chuwu Liu~(a,*) Yun Liu~b ~a Fisheries college,Guangdong Ocean university,Zhanjiang 524025,china ~b college of life science,Hunan normal university,Changsha 410081,china Fisheries college Guangdong Ocean University Zhanjiang 524025 China college of life science Hunan Normal University Changsha 410081 China

The entire mitochondrial DNA sequence (mitogenome) of Russell’s snapper (Lutjanus russellii) was determined using long PCR and primer-walking methodology,representing the first complete mitogenome accessioned for Lutjanid fishes (16,505 bp,GenBank Acces- sion ***514208).The mitogenome was similar in gene composition and order to those of other vertebrates,having 37 structural genes,i.e.,two ribosomal RNAs,22 transfer RNAs,and 13 protein-coding *** analyses based on the mtDNA sequence of Russell’s snapper supported a close relationship between Lutjaninae and Caesioninae,consistent with taxonomic hypotheses based on *** studies utilizing mitogenomes are needed to resolve high-level relationships among snappers.

关键词： Lutjanus russellii Mitochondrial DNA Mitogenome Complete mtDNA sequence Long PCR

SYNTHESIS AND PROPERTIES OF NEW MESOGEN-JACKETED LIQUID CRYSTALLINE POLYMERS

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer science 2000年第2期18卷 139-148页

作者： Qi-ding Mi Qi-feng Zhou Department of Polymer science & Engineering, college of chemistry Peking university, Beijing 100871, china Peking Univ Coll Chem Dept Polymer Sci & Engn Beijing 100871 Peoples R China

Some new mesogen-jacketed liquid crystalline polymers (MJLCP) with polymer backbones, spacers, and mesogenic units of different structures were synthesized by radical polymerization. The mesomorphic behavior of these polymers was examined using differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Their liquid crystallinity is influenced by the variation of polymer backbone, spacer, mesogenic unit and its terminal groups. The results show that 1) a more flexible polymer main-chain is more favorable to the formation of a liquid crystal phase, while 2) a flexible spacer will decrease the 'Jacket Effect' and the liquid crystallinity and 3) a subtle modification of the terminal groups on the mesogenic unit may also have a significant influence on properties of the polymers.

关键词： mesogen-jacketed liquid crystalline polymers polymer backbones spacers mesogenic units liquid crystallinity

The best quadrature based on given Hermite information for the Sobolev class KW^r[a,b]

在线全文

学校读者我要写书评

暂无评论

science china Mathematics 2006年第8期49卷 1146-1152页

作者： WANG Xinghua & YANG Shijun Department of Mathematics, zhejiang university, Hangzhou 310028, china Department of Mathematics, Hangzhou normal college, Hangzhou 310036, china Department of Mathematics Zhejiang University Hangzhou 310028 China Department of Mathematics Hangzhou Normal College Hangzhou 310036 China

As usual, denote by KWr[a,b] the Sobolev class consisting of every function whose (r-1)th derivative is absolutely continuous on the interval [a,b] and rth derivative is bounded by K a.e. In [a,b]. For a function f ∈ KWr[a,b], its values and derivatives up to r-1 order at a set of nodes x are known. These values are said to be the given Hermite *** work reports the results on the best quadrature based on the given Hermite information for the class KWr[a,b]. Existence and concrete construction issue of the best quadrature are settled down by a perfect spline interpolation. It turns out that the best quadrature depends on a system of algebraic equations satisfied by a set of free nodes of the interpolation perfect spline. From our another new result, it is shown that the system can be converted in a closed form to two single-variable polynomial equations, each being of degree approximately r/2. As a by-product,the best interpolation formula for the class KWr[a,b] is also obtained.

关键词： Sobolev class, Hermite information, perfect spline, optimal recovery, best quadrature.

Scenario simulation and forecast of land use/cover in northern china

在线全文

学校读者我要写书评

暂无评论

Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3 & HE ChunYang 3 1 college of Geographical science, Chongqing normal university, Chongqing 400047, china 2 college of Resources and Environmental science, Chongqing university, Chongqing 400044, china 3 college of Resources science & Technology, Beijing normal university, Beijing 100875, china college of Geographical science Chongqing Normal University Chongqing 400047 China college of Resources and Environmental science Chongqing University Chongqing 400044 China college of Resources science & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

Cloning, sequencing and expression of the coat protein gene of Cocksfoot mottle virus

在线全文

学校读者我要写书评

暂无评论

Progress in Natural science:Materials International 2007年第2期17卷 222-225页

作者： DONG Zhi, GUO Xiaoyu, ZHANG Hailong and ZHANG Feiyun ( college of life science, Capital normal university, Beijing 100037, china college of Resources Environment and Tourism, Capital normal university, Beijing 100037, china Beijing Key Laboratory for Resources Environment and Geography Information System, Beijing 100037, china) [a]college of life science Capital Normal University Beijing China [b]college of Resources Environment and Tourism Capital Normal University Beijing China [c]Beijing Key Laboratory for Resources Environment and Geography Information System Beijing China

The coat protein (CP) gene of Cocksfoot mottle virus (CfMV) was amplified by RT-PCR and inserted into expression vector pGEX-4T-1, and the resulting plasmid was designated as pGEXCfMV-JANCP. The fusion protein GST-CP was expressed in BL21 (DE3) pLysS after IPTG induction. The results of SDS-PAGE and Western blot analysis showed that the CfMV-CP gene was efficiently expressed in E. coli BL21 (DE3) pLysS through IPTG induction and the 56.0 kD protein was obtained.

关键词： Cocksfoot mottle virus sequence analysis prokaryotic expression.