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Calcium channel blocking activity of calycosin,a major active component of Astragali Radix,on rat aorta

Acta Pharmacologica Sinica 2006年第8期27卷 1007-1012页

作者： Xiu-li WU~2.Yin-ye WANG~(2.4) Jun CHENG~3.Yu-ying ZHAO~3.~2.epartment of {3. and Cellular Pharmacology:~3.epartment of Natural Medicinal chemistry,School of Pharmaceutical Sciences,{2.,beijing 100083.china Department of molecular and Cellular Pharmacology School of Pharmaceutical Sciences Peking University Beijing China Department of Natural Medicinal chemistry School of Pharmaceutical Sciences Peking University Beijing China

Aim:To investigate the vasoactivity of calycosin,a major active component ofAstragali ***:Experiments were performed on isolated rat thoracicaortic rings pre-contracted with phenylephrine(PHE)or ***:Calycosinproduced a concentration-dependent relaxation on the tissue pre-contractedusing PHE with 4.46±0.13.of pD2.nd 95.85%±2.67% of Emax;or using KCl with4.2.±0.05 of pD2.nd 99.06%±2.15% of Emax,and displaced downwards the con-centration-response curves of aortic rings to PHE or *** relaxant effect ofcalycosin on denuded endothelium aortic rings was the same as on intact endot-helium aortic rings,and its vasorelaxant effect was not influenced by L-NAME *** Ca2.-free solution,calycosin(3. μmol/L)did not have an effecton PHE (1×10-6mol/L)-induced aortic ring *** effects of calycosinand nifedipine where somewhat different;calycosin decreased aortic ring con-tractions induced by the two agonists,but nifedipine displayed a more potentinhibitory effect on KCl-induced contractions than on PHE-induced contractions,and the vascular relaxing effects of calycosin and nifidipine were additive on PHE-induced contraction but not ***:Calycosin is a *** action is endothelium-independent and is unrelated to intracellular Ca2.*** is a noncompetitive Ca2.channel *** effect of calycosin on Ca2.chan-nel blockade may be different from that of *** study demon-strated a novel pharmacological activity of calycosin,and supplied a theoreticfoundation for Astragali Radix application.

关键词： catycosin rat aorta vasodilation calcium channel

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MECHANICAL PERTURBATION INDUCED molecular ALIGNMENTS IN A SIDE-CHAIN LIQUID CRYSTALLINE POLYACETYLENE, POLY{10-[4-(4'-METHOXYPHENOXY-CARBOML)PHENOXYCARBONYL]-1-DECYNE}

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Chinese Journal of Polymer Science 1999年第3期17卷 289-294页

作者： Ben-zhong Tang Xiang-xing Kong Xin-de Feng Department of chemistry, Hong Kong university of Science & Technology, Clear Water Bay, Kowloon, Hong Kong, {2. Department of Polymer Science & {3., college of chemistry, peking university, beijing 100871, {2. Department of chemistry Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong Department of Polymer Science and engineering College of Chemistry Peking University Beijing 100871 China

A new liquid crystalline polyacetylene containing a phenyl benzoate mesogen (5) is synthesized,whose mesomorphic properties are found to be easily 'tunab1e' by simple mechanical perturbation. Thepolymerization of 10- [ 4 - (4' -methoxyphenoxycarbonyl )phenoxycarbonyl] - 1 -decyne (4 ) in itiated by theWCl_6-Ph_4Sn/dioxane complex yields polymer 5 with a M_w of 2.400. The molecular structure of 5 ischaracterized by NMR, IR, and UV spectroscopy and its liquid crystalline behavior is investigated by DSC,POM, and XRD analysis. Upon mechanical perturbation, 5 exhibits unusual agitation-induced high-strengthdisclinations, shear-induced inversion walls, and solidification-induced banded textures. Such phenomenahave been observed in the main-chain liquid crystalline polymers with rigid backbones, but have seldom beenreported for the side-chain liquid crystalline polymers with flexible backbones, suggesting that the rigidpolyacetylene backbone of 5 plays a constructive role in inducing the novel molecular alignments.

关键词： Liquid crystals Side-chain liquid crystalline polymers Polyacetylenes High-strength disclinations Inversion walls Banded textures molecular alignments

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CAPILLARY ZONE ELECTROPHORESIS AND MICELLAR ELECTROKINETIC CAPILLARY CHROMATOGRAPHY OF SOME PROTECTED AMINO ACIDS AND PEPTIDES

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Chinese Chemical Letters 1994年第9期5卷 765-766页

作者： LI ZHANG Rong Hul YANG Sheng JIN(School of chemistry and molecular {2., {3., beijing 100871)

The possibililles of capillary zone clectrophoresis (CZE) and micellar electrokinetic capillary chromatography (MECC) were investigated for the qualitatiee analysis of ten prolected amino acids and peptides. The resul...

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Investigation of 'chazi'(damaged-enamels)on Chenghua doucai Porcelains

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Science china(Technological Sciences) 2009年第6期52卷 1722-1729页

作者： DU Feng1 & SU BaoRu2.1 Institute of chemistry & molecular {2.,Qingdao university of Science & Technology,Qingdao,china 2.college of Information Science & Technology,Qingdao university of Science & Technology,Qingdao,china Institute of chemistry & molecular {2. Qingdao University of Science & Technology Qingdao China college of Information Science & Technology Qingdao University of Science & Technology Qingdao China

At the end of the 1950s,Sun Yingzhou considered that the 'chazi'(damaged colour)on Chenghua doucai imperial porcelain as a defect was originally produced in firing process during Chenghua period(1465―1487).Researchers in china have accepted his *** any fragment with the 'chazi' has never been found in several tons of Chenghua imperial sherds excavated from Ming imperial kiln site in *** china,few scholars have questioned the formation of 'chazi',and further investigated *** researchers at the Research Laboratory in the British Museum,employing unde-structive EDXRF,have analyzed the chemical composition of the 'chazi'(damaged colour)on a Chen-ghua doucai stem cup in the museum,and they have confirmed that the 'chazi'(damaged colour)was caused by the fire of the Jianfu palace in the Forbidden City in *** on their research,the authors studied the colour chemical principle of the 'chazi's' formation *** to the ceramic technology principle,scientific reasoning for the 'chazi' was carried *** the help of the history of Qing court,the brainteaser of the 'chazi' was totally uncovered,the misunderstanding for the 'chazi' has also been *** research also suggests that employing modern science and technology is a direction to study Chinese ancient ceramic further.

关键词： Chenghua doucai porcelains court eunuchs the set on fire at the Jianfu palace ’chazi’(damaged-enamels) the British Museum colour chemical principle archaeology using science and technology

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核开关结构、机制及应用新进展

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生物化学与生物物理进展 2010年第1期37卷 7-13页

作者：何珊来鲁华北京大学化学与分子工程学院北京100871

核开关(riboswitch)是Breaker等在2.02.发现的一种全新的转录后调节机制.它可以通过小分子与mRNA结合来直接调控基因的表达,不需要任何蛋白质的参与.与常见的经由蛋白质的调控方式相比,riboswitch响应更迅速,对细胞内代谢物的变化更敏... 详细信息

核开关(riboswitch)是Breaker等在2.02.发现的一种全新的转录后调节机制.它可以通过小分子与mRNA结合来直接调控基因的表达,不需要任何蛋白质的参与.与常见的经由蛋白质的调控方式相比,riboswitch响应更迅速,对细胞内代谢物的变化更敏感.它的发现为RNA研究展示了新的领域.目前在这个领域,既有基础研究,如riboswitch晶体结构解析、作用机制和动力学研究,又有前沿应用研究,如基于riboswitch的生物传感器和药物设计.Topp等通过设计riboswitch成功地改变了大肠杆菌的趋化性,这为合成生物学和人工生物网络的设计提供了新思路.目前对于riboswitch结构、机制及动力学的研究为基于riboswitch的合理药物设计奠定了基础,有望针对这一新的机制开发新一代抗菌药物.

关键词：核开关(riboswitch) 基因调控药物设计合成生物学

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Polycistronic strategy for cyanobacterial expression vector construction: Co-transcription of a human gene and a selective marker gene

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Progress in Natural Science:Materials International 2005年第9期15卷 798-803页

作者： ZHANG Yukun1, SHI Dingji2. ZHAO Feifei1, YU Meimin1 and RU Binggen1(1. college of Life Science, peking university, {2., china 2. college of Marine Sciences & engineering, Tianjin university of Science & Technology, Tianjin 3.0450, china) college of Life Science Peking University Beijing 100871 China college of Marine Sciences and engineering Tianjin University of Science and Technology Tianjin 300450 China

A polycistronic expression vector, pKGA-NTF1, was constructed for the cyanobacterium. Within this vector, the spectinomycin/streptomycin resistance gene (aadA) facilitated the selection of transformants when co-transcribed with favorite genes. A natural glnA gene was selected as the platform to introduce the plasmid into a neutral site of the Synechococcus sp. PCC 7002.chromosome. Function of the vector was demonstrated by the insertion of a modified human Trefoil factor 3.gene (NTF1) to upstream of the aadA gene and by the analyses of the transformed strains. Antibiotics resistance assays showed that the dicistronic expression cassette conferred high spectinomycin resistance to both the E. coli cells and the Synechococcus cells. PCR analysis and Western-blot analysis were carried out to confirm the integration and expression of the NTF1 gene, respectively. Through simple molecular manipulations, the artificial polycistronic structure described here can be conveniently used to express other favorable genes or operons in cyanobacteria, and to study the cyanobacterial gene expression as well.

关键词： cyanobacterial transformation human Trefoil factor 3 polycistronic expression Synechococcus sp. PCC 7002 vector construction.

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Sensing characterization of Sn/In/Ti nanocomplex oxides for CO, CH_4 and NO_2

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Science china(Technological Sciences) 2007年第1期50卷 18-26页

作者： BAI ShouLi1, TONG ZhangFa2. LI DianQing1, HUANG XiaoWei3. LUO RuiXian1 & CHEN AiFan1 1 State Key Laboratory of Chemical Resource engineering, beijing {2. of Chemical Technology, beijing 10002., china 2.School of chemistry and Chemical engineering, Guangxi {2., Nanning 53.004, china 3.college of Biochemical engineering, beijing Union {2., beijing 10002., china State Key Laboratory of Chemical Resource engineering Beijing University of Chemical Technology Beijing China School of chemistry and Chemical engineering Guangxi University Nanning China college of Biochemical engineering Beijing Union University Beijing China

The nanocomplex oxides of Sn-In and Sn-In-Ti were prepared by controlled co-precipitation method as sensing materials of semiconductor gas sensors for detection of CO, CH4 and NO2. Through manipulating the Sn/In cation ratio, metal salt total concentration, precipitation pH value and aging time, the nanocrystalline powders were successfully derived with chemical homogeneity and superior thermal stability, compared with the single component oxides. The particle size and morphology, surface area, and thermal and phase stabilities were characterized using TEM, TG-DTA, BET and XRD. The sensing tests showed that the Sn-In com-posites exhibit high sensitivity and selectivity for CO and NO2. The introduction of TiO2.enhanced CH4 sensitivity and selectivity, particularly, additives of Pd and Al2.3.as a dopant and surface modification greatly enhanced the sensing properties. The sensitivity depended on the composition of composites, calcination temperature and operating temperature. The optimal values were (2.%In2.3. 75%SnO2.-2.%TiO2.for ternary composite, 600 and 3.0℃, respectively. Temperature-programmed de-sorption (TPD) studies were employed to explain the gas adsorption behavior dis-played by the surface of nanocomposites and X-ray photoelectron spectroscopic (XPS) analysis was used to confirm the electronic interactions existing between oxide components. The sensing mechanism of the nanocomposites was attributed to chemical and electronic synergistic effects.

关键词： SnO2.In2.3.TiO2 nanocomposites CO NO2 CH4 gas sensing

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DESIGN，SYNTHESIS　AND　ACTIVITIES　OF　ANALOGS　AND　SEGMENTS　OF　THE　PAPAVER　SOMNIFERUM　POLLEN　PEPTIDE　PSPP2.1

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Chinese Chemical Letters 1995年第11期6卷 941-942页

作者： Jia Xi XU Sheng JIN (School of chemistry and molecular {2., {3., beijing 100871)(National Laboratory of Applied Organic chemistry at Lanzhou university, Lanzhou 73.000)Meng Shen CAI (School of Pharmaceutical Sciences, beijing Medical beijing Univ Sch Chem & Mol Engn Beijing 100871 Peoples R China Lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China beijing Med Univ Sch Pharmaceut Sci Beijing 100083 Peoples R China

Four analogs and three segments of the Papaver somniferum pollen peptide 2.(PSPP2.were desiged and synthesized by using Merrifield solid phase peptide synthesis method. Their antitumour activities were detrminde by the tetrazolium salt MTT (3.(4,5-dimethylthiazol-2.yl)-2.5diphenyl tetraolium bromide) method and the relationship of tructure -activity was discussed.

关键词： PSPP2.1 PEPTIDE POLLEN SOMNIFERUM ANALOGS ACTIVITIES

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Micro-plate magnetic chemiluminescence immunoassay and its applications in carcinoembryonic antigen analysis

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Science china chemistry 2010年第4期53卷 812-819页

作者： LI ZhiYong1, ZHANG QianYun2. ZHAO LiXia1, LI ZhenJia3. HU GuoMao3. LIN Jin-Ming2.& WANG Shan4 1State Key Laboratory of Environmental chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, {3. 100085, {2. 2.epartment of chemistry, Tsinghua university, {3. 100084, {2. 3.3. Chemclin Biotech Co., Ltd., {3. Academy of Science and Technology, {3. 100094, {2. 4School of chemistry and Chemical {12., Xianyang Normal college, Xianyang 712.00, {2. State Key Laboratory of Environmental chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China Department of chemistry Tsinghua University Beijing China beijing Chemclin Biotech Co. Ltd. Beijing Academy of Science and Technology Beijing China School of chemistry and Chemical engineering of Xianyang Normal {2. Xianyang China

A micro-plate magnetic chemiluminescence immunoassay was developed for rapid and high throughput detection of carcinoembryonic antigens (CEA) in human sera. This method was based on a sandwich immunoreaction of fluorescein isothiocyanate (FITC)-labeled anti-CEA antibodies, CEA antigens, and horseradish peroxidase (HRP)-conjugated anti-CEA antibodies in mi- cro-plate. The immunomagnetic particles coated with anti-FITC antibodies were used as the solid phase for the immunoassay. The separation procedure was carried out by a magnetic plate adaptor and the luminol-hydrogen peroxide (H2.2.-HRP system was employed for the chemiluminescence detection. The proposed method combined the advantages of the micro-plate reactor and magnetic particle separation technology with the linear range of 5-2.0 ng mL·1. The detection limit of CEA was 0.61 ng mL·1. The coefficient of the variation was less than 7% and 13. for intra-assay and inter-assay precision, respectively. Compared with the commercial micro-plate chemiluminescent kit, the proposed method showed a good correlation.

关键词： micro-plate magnetic chemiluminescence immunoassay carcinoembryonic antigen tumor marker

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Formation of super-concentrated hydrochloric acid in the third phase in tertiary amine N2.5-PtCl_6^(2.)-HCl system and its influences on the Pt microemulsion extraction

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Science china chemistry 2009年第11期52卷 1825-1834页

作者： HUANG Kun1,CHEN Jing1,ZHANG ChengFeng1,2.LI ZhiHong3.PAN QingHua1,SUN Yan1,LIU ShaoXuan1,LIU XueXin2.LI WeiHong1,YANG ZhanLan1,WENG ShiFu1,HU TianDou3.XU YiZhuang1 & WU JinGuang1 1 college of chemistry and molecular engineering,{3.,{2.,china 2.Institute of chemistry,Chinese Academy of Sciences,beijing 100190,china 3.Institute of High Energy Physics,Chinese Academy of Sciences,beijing 100049,china college of chemistry and molecular engineering Peking University Beijing China Institute of chemistry Chinese Academy of Sciences Beijing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China

In this paper,we have investigated the formation of the third-phase in tertiary amine(N2.5)-PtCl62.-HCl system and the microscopic phase structural evolution of platinum-loaded organic phases before and after the occurrence of the *** third-phase is characterized by various spectroscopic techniques,and the small angle X-ray scattering(SAXS) experiments demonstrate the appearance of nano-aggregates,i.e.,water-in-oil reversed micelles,in the third *** experimental results indicate that(1) formation of the third phase is related to the aggregation behaviors of nano-reversed micelles in which a super-concentrated hydrochloric acid formed with the H+ to H2. molar ratio being much higher than that of the conventional 3. wt% saturated hydrochloric acid.(2. The occurrence of the super-concentrated HCl results in a great amount of H+ and Cl-ions enriched and confined within the nano-water pools of W/O reversed micelles in third ***,the coordination behaviors of platinum complex ions in that super-concentrated hydrochloric acid are very different from their corresponding behaviors in bulk aqueous *** is possible that H+ ions participate in the formation of such complexes as HmPtCl6z+ in the super-concentrated hydrochloric acid.(3. The relative contents of various HmPtCl6z+ complexes are different corresponding to the H+ ion concentrations in confined nanowater *** association ability of the acidified tertiary amine N2.5 molecules(R3.H+) with various HmPtCl6z+ complexes plays an important role in affecting the platinum extraction behaviors.

关键词： solvent extraction third phase super-concentrated hydrochloric acid tertiary amine platinum

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