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Profile of the composition fractions in neutron stars

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chinese Science Bulletin 2002年第8期47卷 632-634页

作者： LI Wenfei, ZHANG Fengshou & CHEN Liewencenter of Theoretical Nuclear Physics, national Laboratory of Heavy Ion Accelerator, Lanzhou 730000,{2. Institute of Modern Physics, chinese academy of sciences, Lanzhou 730000,{2. Department of Physics, Shangh center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou China Institute of Modern Physics Chinese Academy of Sciences Lanzhou China Department of Physics Shanghai Jiao Tong University Shanghai China

The composition fractions of β-stable neutron stars and their radial distributions are investigated based on Skyrme-Hartree-Fock theory and Tolman-Oppenheimer-Volkoff (TOV) equation. It is found that a pure neutron interior with a radius of 3.5 km can exist in the neutron stars. When the radius is greater than 3.5 km, the fractions of the proton, electron and μ- appear and increase with the increment of the radius, then decrease after reaching their maximum at the radius of 8 km. These results make it possible to further study the thermal evolution and magnetic properties of the neutron stars.

关键词： neutron stars compositon fractions asymmetric nuclear matter equation of state Tolman-Oppenheimer-Volkoff equation.

Present status and development on biological nitrogen fixation research in china

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chinese Science Bulletin 2003年第10期48卷 954-960页

作者： SHEN Shihua & JING Yuxiang Key Laboratory of Photosynthesis and Plant-Environment MolecularPhysiology, Institute of Botany, chinese academy of sciences, Beijing 100093, china Key Laboratory of Photosynthesis and Plant-Environment Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

This presentation introduces the advances inbiological nitrogen fixation research abroad, in particular,describes the great progress and achievements on itsresearch in{2. as follows: collection of rhizobial resources and establishment of the largest database of Rhizobium inchina, correction and development of Rhizobium taxonomy in international; discovery of a couple of nif genes,identification and unification of linkage among the nif gene operons of Klebsiella pneumoniae, finding of regulative mechanism of positive regulation nif gene and its sensitivity to oxygen, temperature; finding of the activity of nodulation gene nodD3 product in Sinorhizobium meliloti which is notcontrolled by flavonoid produced from its host alfalfa;finding of the association between expression of genes coding the products for carbon utilization and nitrogen metabolism and their regulations; chemical synthesis of nodulationfactor of Sinorhizobium meliloti; constructions of engineered nitrogen fixers and utilization in practice based on theresearch of gene expression and regulation; chemicalsimulation of the structure and function of nitrogenase and bringing forward the model of nitrogenase active {12. for the first time in international and synthesis of modelcompounds which were paid attention by colleagues abroad. Finally, the development of nitrogen fixation research inchina in future has been put forward, suggesting that the nifgene regulation and its role in providing crops with nitrogen element, signal transduction and molecular interactions between Rhizobium and legume, coupling between carbonand nitrogen metabolisms, nitrogen fixation andphotosynthesis, and functional genomics of nitrogen-fixing nodule symbiosis, etc., would be actively worked on.

关键词：现状发展生物固氮技术中国固氮酶基因表达微生物植物相互作用化学模型

Chondrogenic differentiation of mouse embryonic stem cells promoted by mature chondrocytes

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Science china(Life sciences) 2008年第9期51卷 774-778页

作者： XIE Feng, ZHANG WenJie, CHEN FanFan, ZHOU GuangDong, CUI Lei, LIU Wei & CAO YiLin Department of Plastic and Reconstructive Surgery, shanghai 9th People’s Hospital national Tissue Engineering {2. of china, School of Medicine, shanghai JiaoTong University, shanghai 2.0011, china 1. Department of Plastic and Reconstructive Surgery Shanghai 9th People’s Hospital Shanghai 200011 China 2. national Tissue Engineering center of{2. School of Medicine Shanghai JiaoTong University Shanghai 200011 China

In order to direct embryonic stem (ES) cells to differentiate into chondrocytes, a chondrogenic envi-ronment provided by mature chondrocytes was investigated. Flk-1 positive cells sorted from pre-differentiated mouse ES cells were mixed with adult porcine articular chondrocytes, seeded on biodegradable scaffolds, and then implanted subcutaneously into nude mice. The cell-scaffold com-plexes formed cartilage tissues after 4 weeks, which was demonstrated by histology and anti-type II collagen antibody staining. Positive staining of mouse Major Histocompatibility Complex class I molecules confirmed that part of the chondrocytes were derived from mouse ES cells. The current study established a new approach for directing ES cell differentiation.

关键词： chondrocytes co-culture differentiation embryonic stem cells

generation and Characterization of C305,a Murine Neutralizing scFv Antibody That Can Inhibit BLyS Binding to Its Receptor BCMA

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Acta Biochimica et Biophysica Sinica 2005年第6期37卷 415-420页

作者： Mei-Yun LIU~(1.2. Wei HAN~(2.3) Yan-Li DING~(2.3) Tian-Hong ZHOU~1 Rui-Yang TIAN~2.Sheng-Li YANG~2.Hui LIU~2.Yi GONG~2. 1 College of Life Science and Technology,Jinan University. Guangzhou 510632. china 2.shanghai {2. center of Biotechnology.shanghai Institutes for Biological sciences. chinese academy of sciences. shanghai 2.02.3,china 3 School of Pharmaceatical Engineering, Shenyang Pharmaceutical University. Shenyang 110016. china CollegeofLifeScienceandTechnology JinanUniversityGuangzhou510632China

B-lymphocyte stimulator(BLyS)is a member of the tumor necrosis factor(TNF)family anda key regulator of B cell *** single-chain fragment variable(scFv)antibody against BLySbinding to its receptor BCMA has the potential to play a prominent role in autoimmune disease *** display scFv library constructed on pⅢ protein of M13 filamentous phage was screened using *** five rounds of panning,their binding activity was characterized by *** sequencingrevealed that at least two different scFv gene fragments(C305 and D416)were *** two differentscFv gene fragments were expressed to obtain the soluble scFv antibodies,then the soluble scFv antibodieswere characterized by means of competitive ELISA and in vitro neutralization *** results indicatedthat C305 is the neutralizing scFv antibody that can inhibit BLyS binding to its receptor BCMA.

关键词： phage display neutralizing scFv antibody BLyS

Chemical synthesis of a structure gene coding for small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase from tobacco

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chinese Journal of Chemistry 1994年第4期12卷 355-364页

作者： CHEN, Hai-Bao WENG, Jie-Min BAO, Jian-Shaoshanghai Institute of Organic Chemistry, Chinses academy of {2., 354 Fenglin Lu, shanghai 2.0032. china shanghai Institute of Organic Chemistry Chinses Academy of Sciences 354 Fenglin Lu Shanghai 200032 China

A structural gene with 385 bp, which codes for the mature small subunit (rbcS) of ribulose-1,5-bi9phosphate carboxylase/oxygenase from tobacco, has been redesigned according to the codon usage of *** and chemically synthesized. To facilitate the systematic investigation of structure-functional relationship of the rbcS by site-specific mutagenesis, twenty one unique restriction sites distributed throughout the synthetic gene were designed. gene synthesis was started from chemically synthesizing sixteen oligonucleotides each with 2.-66 nucleotides, and these oligonu-cleotides were annealed to form eight duplexes from which 5'- and 3'- two half molecules were formed by stepwise T4 DNA ligase reaction, and then each half molecule was cloned into plasmid pWR13, after that, two half molecules were further confirmed by DNA sequencing, finally both half molecules excised from the cloning plasmid were recombinated to form plasmid pCOTrbcS containing the whole structural gene for tobacco rbcS.

关键词： gene synthesis ribulose-1,5-bisphosphate carboxylase/oxygenase clone.

Screen for stage-specific expression genes between tail bud stage and heartbeat beginning stage in embryogenesis of gynogenetic silver crucian carp

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Cell research 2002年第2期12卷 133-142页

作者： YAO HUA SHI, JUN LIU, JIAN HONG XIA, JIAN FANG GUIState Key laboratory of Freshwater Ecology and Biotechnology, Wuhan center for Developmental Biology, Institute of Hydrobiology, chinese academy of sciences, Wuhan 430072.{2. 1State Key laboratory of Freshwater Ecology and Biotechnology Wuhan Center for Developmental Biology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China 1State Key laboratory of Freshwater Ecology and Biotechnology Wuhan Center for Developmental Biology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China 1State Key laboratory of Freshwater Ecology and Biotechnology Wuhan Center for Developmental Biology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China 1State Key laboratory of Freshwater Ecology and Biotechnology Wuhan Center for Developmental Biology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

A systemic study was initiated to identify stage-specific expression genes in fish embryogenesis by using suppression subtractive hybridization (SSH) technique. In this study, we presented a preliminary result on screen for stage-specific expression genes between tail bud stage (TBS) and heartbeat beginning stage (HBS) in gynogenetic silver crucian carp (Carassius auratus gibelio). Two SSH plasmid libraries specific for TBS embryos and HBS embryos were constructed, and stage-specific expression genes were screened between the two stages. 1963 TBS positive clones and 2.66 HBS positive clones were sampled to PCR amplification, and 1373 TBS and 1809 HBS PCR positive clones were selected to carry out dot blots. 169 TBS dot blot positive clones and 2.2.HBS dot blot positive clones were sequenced. Searching GenBank by using these nucleotide sequences indicated that most of the TBS dot blot positive clones could not be found homologous sequences in the database, while known genes were mainly detected from HBS d

关键词： SSH embryonic development differential expression genes gynogenesis silver crucian carp.

p53 Promoter-based Reporter gene in vitro Assays for Quick Assessment of Agents with Genotoxic Potential

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Acta Biochimica et Biophysica Sinica 2007年第3期39卷 181-186页

作者： Huaixing LI~(2.) Ke SHI~(1#) Ruiwen CHEN~1 Yan HE~1 Dan WU~1 Shuhan SUN~1* 1 Department of Medical genetics.Division of Basic Medical sciences,Second Military Medical University,{2. 2.0433,china 2.Institute for Nutritional sciences.{2. Institutes of Biological sciences,chinese academy of sciences,{2. 2.0031,china DepartmentofMedicalgenetics DivisionofBasicMedicalSciencesSecondMilitaryMedicalUniversityShanghai200433China InstituteforNutritionalsciences ShanghaiInstitutesofBiologicalSciencesChineseAcademyofSciencesShanghai

The p53 promoter-based green fluorescent protein(GFP)and luciferase reporter gene assayshave been established for detecting DNA damage induced by genotoxic *** evaluate the system,NIH3T3 cells transfected with either pHP53-GFP or pMP53-GFP construct were treated with mitomycin *** of the GFP reporter gene was significantly and specifically induced in the cellsexposed to mitomycin or *** we treated NIH3T3 cells harboring pHP53-Luc or pMP53-Luc vector with mitomycin,5-fluorouracil or cisplatin at various ***,exposure of thecells to these agents with genotoxic potentials resulted in a dose-dependent induction in luciferase reportergene ***,these in vitro reporter gene assays could provide an ideal system for quick assess-ment or screening of agents with genotoxic potential.

关键词： p53 promoter luciferase green fluorescence protein(GFP) genotoxic agent

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神经钙粘着蛋白在P19神经元分化中的作用

生物化学与生物物理学报 1999年第5期31卷 610-613页

作者：高翔杨靖边玮景乃禾中国科学院上海生物化学研究所!上海2.0031 上海生命科学研究中心上海200031中国科学院上海生物化学研究所!上海200031

利用ＲＴ ＰＣＲ技术，我们检测了Ｐ１９细胞体外神经元分化过程中神经钙粘着蛋白（Ｎｃａｄｈｅｒｉｎ）的表达模式。结果显示，该基因在上述过程中存在上调和下调过程，与体内中枢神经系统发育过程的表达模式十分相... 详细信息

利用ＲＴ ＰＣＲ技术，我们检测了Ｐ１９细胞体外神经元分化过程中神经钙粘着蛋白（Ｎｃａｄｈｅｒｉｎ）的表达模式。结果显示，该基因在上述过程中存在上调和下调过程，与体内中枢神经系统发育过程的表达模式十分相近。在此基础上，我们将神经钙粘着蛋白基因ｃＤＮＡ全长转入Ｐ１９细胞，通过药物筛选，得到了稳定表达神经钙粘着蛋白的细胞株。转基因细胞株不经ＲＡ诱导，就能自发向神经元方向分化，并表达神经元特异的分子标记物ＮＦ１６０。以上结果提示：神经钙粘着蛋白可引起Ｐ１９细胞在体外自发向神经方向分化，在Ｐ１９神经元的分化过程中起重要作用。

关键词：神经钙粘着蛋白 P19神经

Relationships of Aegilops tauschii revealed by DNA fingerprints:The evidence for agriculture exchange between china and the West

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Progress in Natural Science:Materials International 2008年第12期18卷 1525-1531页

作者： Huiting Wei~a Jun Li~a Zhengsong Peng~b Baorong Lu~c Zhijun Zhao~d Wuyun Yang~a a Crop research Institute,Sichuan academy of Agricultural {2.,Chengdu 610066,china b Life Science College,china West Normal University,Nanchong 637002.china c The Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering,Institute of Biodiversity Science,Fudan University,shanghai 2.0433,china d chinese academy of Social Science,Beijing 110710,china [a]Crop research Institute Sichuan Academy of Agricultural Sciences Chengdu 610066 China [b]Life Science College China West Normal University Nanchong 637002 China [c]The Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Institute of Biodiversity Science Fudan University Shanghai 200433 China [d]chinese academy of Social Science Beijing 110710 China

genetic diversity and relationships of wild goat grass (Aegilops tauschii Cosson) from Iran and Xinjiang,west china,as well as its weedy type from the Yellow River region of Shaanxi and Henan provinces in china were analyzed by simple sequence repeat (SSR) fingerprints.A high level of genetic diversity in Aegilops tauschii accessions from Iran was observed,and the richness of genetic diversity was followed by accessions from Shaanxi,Henan,and *** weedy type of Aegilops tauschii showed a close genetic relationship with the wild type from different regions in *** results indicated that the weedy Aegilops tauschii found in the Yellow River region was most likely introduced from Iran—the diversity center of Aegilops *** weedy Aegilops tauschii populations found in the Yellow River region may be brought into the central part of china as a weed species together with common wheat (Triticum aestivum L.) from the West during various periods of time in *** finding has provided strong evidence for the introduction of common wheat from the West into china via the Silk Road,and also demonstrated the important role of the Silk Road in the exchange of agri- culture and other relevant technologies between china and the West.

关键词： The Silk Road Aegilops tauschii Common wheat SSR fingerprints genetic diversity Affinity Crop dispersion