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Immortal solution of the Ricci flow

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Science china Mathematics 2005年第Z1期48卷 217-224页

作者： RUAN Qihua & CHEN Zhihua department of Applied Mathematics, tongji university, shanghai 200092, china department of Mathematics, Putian college, Putian 351100, china department of Applied Mathematics Tongji University Shanghai China department of Mathematics Putian College Putian China

For any complete noncompact Kahler manifold with nonnegative and bounded holomorphic bisectional curvature, we provide the necessary and sufficient condition for the immortal solution to the Ricci flow.

关键词： Ricci flow, immortal solution, holomorphic bisectional curvature.

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Macro-micromechanical approaches for non-coaxiality of coarse grained soils

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中国科学：技术科学英文版 2011年第S1期54卷 147-153页

作者： QIAN JianGu 1,2,HUANG MaoSong 1,2 & SUN HaiZhong 1,2 1 Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education,tongji university,shanghai 200092,china 2 department of Geotechnical Engineering,tongji university,shanghai 200092,china Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji University Shanghai China department of Geotechnical Engineering Tongji University Shanghai China

For coarse grained soils,their principal stress directions may change when the water level of embankment dam varies *** this loading case,the principal directions of stress and strain rate will become *** an effort to model non-coaxial behavior,a modified three-dimensional non-coaxial model is developed in the context of vertex yield(tangent plasticity) *** Element Method(PFC) incorporating user-defined interparticle contact models is also employed to gain an insight into microscopic mechanism of *** analysis focuses on non-coaxial behaviors under simple shear *** has been shown that the proposed non-coaxial model gives good predictions for non-coaxiality with reference to microscopic observations while the classical coaxial model fails to simulate the non-coaxial *** general,non-coaxiality as a result of the rotation of principal stress,is large at a small shear strain,and inclined to become negligible with increasing shear *** coarse grained soils,their non-coaxiality tends to largely depend on the initial normal pressure,where a larger degree of non-coaxiality can be observed at a higher pressure.

关键词： coarse grained soils non-coaxiality particle flow code simple shear

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Expression of estrogen receptor （ER） -α and -βtranscripts in the neonatal and adult rat cerebral cortex, cerebellum, and olfactory bulb

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Cell Research 2001年第4期11卷 321-324页

作者： GUO XING ZHONG, JUN DA SU, QING WEN SUN, BING HUA JIAO department of biochemistry and Molecular Biology, Second Military medical university, shanghai 200433 School of Life Sciences and medical Engineering, tongji university, shanghai 200092, china Shangha department of biochemistry and Molecular Biology Second Military Medical University Shanghai School of Life Sciences and medical Engineering Tongji University Shanghai China shanghai Institute of Physiology Chinese Academy of Sciences Shanghai China

In the present study expression of estrogen receptor subtype -α(ERα) and -β (ERβ) in the cerebral cortex, cerebellum, and olfactory bulb was investigated and compared between neonatal (1～3-days-old) and adult (250～350g) rats, using reverse transcription-polymerase chain reaction (RT- PCR). No ERα transcripts were detectable in the adult cerebellum and olfactory bulb, whereas very weak expression of ERα was present in the adult cerebral cortex. No significant difference in ERβ transcripts was detectable between the neonatal and adult rats. While transcripts for both ER subtypes were co-expressed in these brain areas of neonatal rats, although ERα expression was significantly weaker than ERβ. Even in the cerebral cortex known to contain both ER subtypes in adult rats, ERα transcripts in neonatal rats were much higher than in adult. These observations provide evidence for the existence of different expression patterns of ERcα/ERβ transcripts in these three brain areas between the neonatal and adult rats, suggesting that each ER subtype may play a distinct role in the regulation of differentiation, development, and functions of the brain by estrogen.

关键词： Cerebellum cerebral cortex estrogen receptor (ER) olfactory bulb RT-PCR.

SIMULATION OF NON-POINT POLLUTANTS EVOLUTION IN COASTAL PLAIN ISLAND-A CASE STUDY OF CHONGMING ISLAND

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Journal of Hydrodynamics 2008年第2期20卷 246-253页

作者： YIN Hai-long JIANG Wen-yan LI Jian-hua college of Environmental Science and Engineering Tongji University Shanghai 200092 China department of Environmental Science East China Normal University Shanghai 200063 China

The coastal plain region usually shows the agricultural dominated industry mode, so more and more attention is paid to non-point pollutants discharge. In this study, the method for assessing the influence of non-point pollutants discharge on river water quality is probed which is concluded as follows：（1） Considering the costal plain island is characterized as nearly even elevation, the conventional gravitational runoff confluence method based on eight-point gravitational flowing directions （DS） is unable to compute the runoff confluence received by the surrounding rivers, so a new method of triangular confluence based on three-points of grid center and the river segments is presented. Further the equations of non-point pollutants loads estimation and non-point pollutants confluence on rivers are presented. （2） The integration mode of non-point pollutants model and river water quality model is presented so as to further assess the non-point pollutants contribution to river water quality. （3） With the Chongming Island, the third largest island in china, as an example, the above-mentioned equations are specified. For this island, the non-point pollutants loads are estimated and linked to the developed water quality model of the river network in the island, and further the non-point pollution evolution in river network is simulated. In this scenario, the non-point pollution contribution to river water quality over the whole island is clearly displayed, and the area where the river water quality is seriously influenced by non-point pollutants discharge is distinctly depicted. This scenario also shows the water quality contribution ratio of non-point pollution to point pollution can be in the range of 55.5% to 44.5% which proves the importance of non-point pollution control in costal plain islands.

关键词： non-point pollution runoffconfluence water quality model Chongming Island

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Reduction of tumorigenicity of SMMC-7721 hepatoma cells by vascular endothelial growth factor antisense gene therapy

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World Journal of Gastroenterology 2001年第1期7卷 22-27页

作者： Yu Cheng Tang Yu Li Guan Xiang Qian department of biochemistry, shanghai Second medical university, shanghai 200025, china department of biochemistry Shanghai Second Medical University Shanghai 200025China. tangyc@***

AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. METHODS: Amplify the 200 VEGF cDNA fragment and insert it into human U6 gene cassette in the reverse orientation transcribing small antisense RNA which could specifically interact with VEGF165, and VEGF121 mRNA. Construct the retroviral vector containing this antisense VEGF U6 cassette and package the replication-deficient recombinant retrovirus. SMMC-7721 cells were transduced with these virus and positive clones were selected with G418. PCR and Southern blot analysis were performed to determine if U6 cassette integrated into the genomic DNA of positive clone. Transfected tumor cells were evaluated for RNA expression by ribonuclease protection assays. The VEGF protein in the supernatant of parental tumor cells and genetically modified tumor cells was determined with ELISA. In vitro and in vivo growth properties of antisense VEGF cell clone in nude mice were analyzed. RESULTS: Restriction enzyme digestion and PCR sequencing verified that the antisense VEGF RNA retroviral vector was successfully *** G418 selection, resistant SMMC-7721 cell clone was picked up. PCR and Southern blot analysis suggested that U6 cassette was integrated into the cell genomic DNA. Stable SMMC-7721 cell clone transduced with U6 antisense RNA cassette could express 200 bp small antisense VEGF RNA and secrete reduced levels of VEGF in culture condition. Production of VEGF by antisense transgene-expressing cells was 65+/-10 ng/L per 10(6) cells, 42045 ng/L per 10(6) cells in sense group and 485+/-30 ng/L per 10(6) cells in the negative control group, (P21 cells and SMMC-7721 cells transfected sense VEGF. The growth rate of the antisense-VEGF cell clone was the same as the control cells. When S.C. was implanted into nude mice, growth of antisense-VEGF c

关键词： Gene Therapy Animals Carcinoma, Hepatocellular Cell Division DNA Polymerase III Endothelial Growth Factors Endothelium, Vascular Enzyme-Linked Immunosorbent Assay Gene Expression Humans Liver Neoplasms Lymphokines Mice Mice, Nude Neovascularization, Pathologic Promoter Regions (Genetics) RNA, Antisense Research Support, Non-U.S. Gov't Transduction, Genetic Tumor Cells, Cultured Vascular Endothelial Growth Factor A Vascular Endothelial Growth Factors

Establishment of a Screening System for Selection of siRNA Target Sites Directed against Hepatitis B Virus Surface Gene

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Acta Biochimica et Biophysica Sinica 2005年第5期37卷 310-316页

作者： Xiu-Min ZHOU~(1.3) Ju-Sheng LIN~1 Yi SHI~3 De-An TIAN~2 Huan-Jun HUANG~2 He-Jun ZHOU~1 You-Xin JIN~3 1 Institute of Liver Diseases. tongji Hospital, tongji medical college, Huazhong university of Science and Technology, Wuhan 430030, china: 2 department of Gastroenterology, tongji Hospital, tongji medical college, Huazhong university of Science and Technology, Wuhan 430030, china 3 State Key Laboratory of Molecular Biology, Institute of biochemistry and Cell Biology,shanghai Institutes for Biological Sciences,Chinese Academy of Sciences, shanghai 200031, china Institute of Liver Diseases Tongji Hospital Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China department of Gastroenterology Tongji Hospital Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China

To study the inhibitory effects of plasmid-derived small interfering RNA(siRNA)andsynthetic siRNA on the expression of the hepatitis B virus surface(HBs)gene,three plasmid-derived siRNAsand one synthetic siRNA that complement the coding region of the HBs gene were *** HBsexpression plasmid pHBs-EGFP was also *** cells were co-transfected with pHBs-EGFPand the above *** HBs mRNA quantities were measured by reverse-transcription PCR,and thelevel of HBs-EGFP fusion protein was quantified by fluorescent *** concentrations of thehepatitis B virus surface antigen(HBsAg)derived from the culture supernatant of transfected HepG2.2.15cells were measured by an enzyme-linked immunosorbent assay(ELISA)*** results showed that thethree plasmid-derived siRNAs and the synthetic siRNA can effectively reduce the quantities of HBs mRNAand *** plasmid-derived siRNA psiRNA1 was found to be the most effective inhibitor of *** can inhibit HBs-EGFP expression by 63.3% and suppress HBs mRNA by 75.6%.To furthersubstantiate the above observations,psiRNA1 was transfected into HepG2.2.15 cells(an HBV secreting cellline).The transfections resulted in almost complete blockage of HBsAg production,whereas control vector-transfected cells secreted high levels of HBsAg 7 days *** conclusion,our data suggeststhat RNA interference(RNAi)is an efficient approach for reducing the level of HBs transcripts and proteinsand for suppressing HBsAg production.

关键词： RNA interference(RNAi) small interference RNA(siRNA) hepatitis B virus surface gene(HBs gene)

Autoantibody against Cardiac β1-Adrenoceptor Induces Apoptosis in Cultured Neonatal Rat Cardiomyocytes

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Acta Biochimica et Biophysica Sinica 2006年第7期38卷 443-449页

作者： Yan GAO~1 Hui-Rong LIU~1 Rong-Rui ZHAO~1 Jian-Ming ZHI~(2*) 1 department of Cardiovascular Physiology Shanxi medical university,Taiyuan 030001,china 2 department of Physiology,shanghai Jiaotong university,college of Basic Medicine,shanghai 200025,china department of Cardiovascular Physiology Shanxi Medical UniversityTaiyuan 030001 China department of Physiology Shanghai Jiaotong University College of Basic MedicineShanghai 200025 China

To clarify whether apoptosis is involved in the injury processes induced by autoantibodyagainst cardiac β1-adrenoceptor,we investigated the biological and apoptotic effects of antibodies on culturedneonatal rat *** rats were immunized with peptides corresponding to the second extra-cellular loop of the β1-adrenoceptor to induce the production of anti-β1-adrenoceptor antibodies in the ***（Ig）G in the sera was detected using synthetic antigen enzyme-linked immunosorbentassay and purified using the diethylaminoethyl cellulose ion exchange *** of cardiomyo-cytes was evaluated using agarose gel electrophoresis and flow *** results showed that thepositive serum IgG greatly increased the beating rates of cardiomyocytes and showed an"agonist-like"***,positive serum IgG induced cardiomyocyte apoptosis after treatment with β1-adrenoceptor overstimulation for *** effects of monoclonal antibody against β-adrenoceptor werealso found to be similar to those of positive serum *** was suggested that the autoantibody could inducecardiomyocyte apoptosis by excessive stimulation of β1-adrenoceptor.

关键词： β1-adrenoceptor rat cardiomyocyte autoantibody apoptosis

Effects of Shark Hepatic Stimulator Substance on the Function and Antioxidant Capacity of Liver Mitochondria in an Animal Model of Acute Liver Injury

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Acta Biochimica et Biophysica Sinica 2005年第8期37卷 507-514页

作者： Qiu-Ling FAN~(1,2) Cai-Guo HUANG~(2*) Yan JIN~2 Bo FENG~2 Hui-Nan MIAO~2 Wen-Jie LI~2 Bing-Hua JIAO~2 Qin-Sheng YUAN~(1*) ~1 State Key Laboratory of Bioreactor Engineering.East china university of Science and Techology,shanghai 200237.china ~2 department of biochemistry and Molecular Biology,Second Military medical university.shanghai 200433.china State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai 200237 China department of biochemistry and Molecular Biology Second Military Medical UniversityShanghai 200433 China

This study was carried out to investigate whether shark hepatic stimulator substance(HSS)can prevent acute liver injury and affect mitochondrial function and antioxidant defenses in a rat model ofthioacetamide(TAA)-induced liver *** acute liver injury was induced by two intraperitoneal injectionsof TAA(400 mg/kg)in a 24 h *** the TAA plus shark HSS group,rats were treated with shark HSS(80 mg/kg)I h prior to each TAA *** this group,serum liver enzyme activities were significantlylower than those in the TAA *** mitochondrial respiratory control ratio was improved,and themitochondrial respiratory enzyme activities were increased in the TAA plus shark HSS *** mitochondrialantioxidant enzyme activities and glutathione level were higher in the TAA plus shark HSS group than in theTAA *** results suggest that the protective effect of shark HSS against TAA-induced acute liverinjury may be a result of the restoration of the mitochondrial respiratory function and antioxidant defensesand decreased oxygen stress.

关键词： shark hepatic stimulator substance acute liver injury mitochondrion respiratory function antioxidant capacity

cDNA Cloning of Two Novel T-superfamily Conotoxins from Conus leopardus

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Acta Biochimica et Biophysica Sinica 2006年第4期38卷 287-291页

作者： Wei-Hua CHEN~(1,2#) Yu-Hong HAN~(2,3#) Qi WANG~(2,3#) Xiao-Wei MIAO~(2,4) Ling OU~1 Xiao-Xia SHAO~2* 1 Bioengineering Institute,East china university of Science and Technology,shanghai 200237,china 2 Institute of Protein Research,tongji university,shanghai 200092,china 3 Institute of biochemistry and Cell Biology,shanghai Institute of Biochemical Sciences,Chinese Academy of Sciences,shanghai 200031,china 4 department of Biological Engineering,School of Life Science,shanghai university,shanghai 200436,china Bioengineering Institute East China University of Science and TechnologyShanghai 200237 China Institute of Protein Research Tongji UniversityShanghai 200092 China Institute of biochemistry and Cell Biology Shanghai Institute of Biochemical Sciences Chinese Academy of SciencesShanghai 200031 China department of Biological Engineering School of Life Science Shanghai UniversityShanghai 200436 China

The full-length cDNAs of two novel T-superfamily conotoxins,Lp5.1 and Lp5.2,were clonedfrom a vermivorous cone snail Conus leopardus using 3'/5'-rapid amplification of cDNA *** cDNA ofLp5.1 encodes a precursor of 65 residues,including a 22-residue signal peptide,a 28-residue propeptide anda 15-residue mature ***5.1 is processed at the common signal site -X-Arg- immediately before themature peptide *** the case of Lp5.2,the precursor includes a 25-residue signal peptide anda 43-residue sequence comprising the propeptide and mature peptide,which is probably cleaved to yield a29-residue propeptide and a 14-residue mature *** these two conotoxins share a similar signalsequence and a conserved disulfide pattern with the known T-superfamily,the pro-region and mature peptidesare of low identity,especially Lp5.2 with an identity as low as 10.7% compared with the reference *** elucidated cDNAs of these two toxins will facilitate a better understanding of the species distribution,the sequence diversity of T-superfamily conotoxins,the special gene structure and the evolution of thesepeptides.

关键词： Conus leopardus T-superfamily conotoxin cDNA cloning