检索结果-南通市图书馆

图书馆论坛 2004年第2期24卷 133-137页

作者：肖永英潘妙辉陈小敏中山大学信息管理系广东广州510275 广东省立中山图书馆广东广州510110

阐述了有关广东省公共图书馆信息服务调查研究的目的和方法 ;详细说明本次调查研究的主要内容和结果 ,其中包括作为调查对象的图书馆的基本情况、图书馆信息服务提供的方式。

关键词：广东公共图书馆信息服务社区服务信息咨询联机检索网络服务

Preparative isolation and purification of 1.,1.-dihydroxyeuparin from Radix Eupatorii Chinensis by high-speed counter-current chromatography

在线全文

学校读者我要写书评

暂无评论

Journal of Pharmaceutical Analysis 2012年第4期2卷 258-263页

作者： Mei Yang a,b , Xin-Jun Xu a,b,Chun-Yan Xie a,b , Jie-Yun Huang a,b , Zhi-Sheng Xie a,b , De-Po Yang a,b a School of Pharmaceutical sciences, {1., guangzhou 51.006, China b Guangdong technology Research Center for Advanced Chinese Medicine, guangzhou 51.006, China School of Pharmaceutical sciences Sun Yat-Sen University Guangzhou 510006 China. Guangdong technology Research Center for Advanced Chinese Medicine Guangzhou 510006 China.

An efficient method for the isolation and purification of 1.,1.-dihydroxyeuparin from Radix Eupatorii Chinensis by high speed counter-current chromatography (HSCCC) was established in this paper. The ether extracts of Radix Eupatorii Chinensis were purified by HSCCC with a solvent system of hexyl hydride-ethyl acetate-methanol-water (1.2:1.2, v/v/v/v). The upper phase was used as the stationary phase and the lower phase as the mobile phase. About 8.4 mg of 1., 1.-dihydroxyeuparin was obtained from 200 mg of ether extracts from Radix Eupatorii Chinensis in one-step HSCCC separation, with the purity of 96.71., as determined by HPLC. After methanol- water recrystallization, the purity of 1.,1.-dihydroxyeuparin reached 99.83%. Such a simple and effective method was fairly useful to prepare pure compound as reference substances for related study on Radix Eupatorii Chinensis.

关键词： Radix Eupatorii Chinensis High speed counter- current chromatography (HSCCC) 1.,1.-dihydroxyeuparin

Laminar-specific synaptic plasticity in mouse visual cortex

在线全文

学校读者我要写书评

暂无评论

Laminar-specific synaptic plasticity in mouse visual cortex

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： Bin JIANG Neuroscience Researcher Center,{1. of Physiology,Zhongshan School of Medicine,sun yat-sen university, guangzhou 51.080,China

＜正＞Cortex is a laminated *** to the primary flow of information in the cortex,the layer 4 of cortex receives visual information from LGN,and relays the integrated information into layer 2/*** neurons in layer 4 and layer 2/3 have different shape in somas and dendrites and each cortical layer has specific input and output connections as well as specialized local circuitry,we hypothesize that neurons in different layers may have different properties in synaptic plasticity that are likely tuned to the particular functional requirements of each *** address this,both the excitatory synaptic plasticity and the inhibitory synaptic plasticity were *** whole cell recordings,LTP/LTD of excitatory transmission is induced by pairing protocol while LTD of inhibitory transmission （iLTD） was induced with TBS at the presence of APV and *** findings are:（1. In star pyramidal cells in layer 4 of the visual cortex,LTP and LTD of excitatory synapses become uninducible shortly after eye opening,whereas in pyramidal neurons in layer 2/3 these forms of synaptic plasticity still persist beyond puberty.（2） Visual deprivation by dark rearing does not have any effect on the induction of LTP/LTD in layer 4,while in the layer 2/3 of visual cortex of light-deprived mice,the LTP is enhanced and LTD is diminished.（3） TBS induces LTD of inhibitory transmission （iLTD） in the pyramids in layer 2/3 but does not do so in the star pyramids in layer 4.（4） LTP and LTD of excitatory synapses in layer 4 and layer 2/3 are NMDA- dependent,iLTD is *** results suggest that there was a sequential development of LTP/LTD of excitatory synapses in different ***-mediated iLTD was only induced in layer 2/3 of developing visual cortex,demonstrating a laminar-specific synaptic plasticity in both excitatory transmission and inhibitory transmission.

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

使用约束条件支持领域本体的重用

计算机科学 2004年第4期31卷 104-107页

作者：明仲蔡树彬李师贤中山大学计算机科学系

在利用领域本体知识库(DOKB)中已有领域本体构造新的领域模型或领域本体后,知识工程师需要检查新领域本体以确保其符合规则前提。使用约束条件可以令计算机自动解决这个问题,从而减少知识工程师的工作量,并加快知识的重用过程。

关键词：软件工程领域知识库 CASE 领域本体约束条件计算机

Preparation and characteristics of interfero poly(lactic-co-glycolic acid) microspheres

在线全文

学校读者我要写书评

暂无评论

Preparation and characteristics of interfero poly(lactic-co-...

用于大气污染扩散模拟的虚拟地理环境构建研究

201.年广东省药师周大会

作者： FanYang1.Feng-LanSong1.Yu-Fang Pan1.Zhao-Yang Wang2,Yi-qun Yang1.Yao-Ming Zhao3,Shi-Zhong Liang2 and Yong-Ming Zhang3 1.0} of Pharmacy,Guangdong Pharmaceutical {1.,guangzhou,PR China,2 Institute of Materials,South China {1. of technology,guangzhou,PR China,and 3 department of Pharmacy,The Third Affiliated Hospital,sun yat-sen university,guangzhou,PR China

By a double emulsion solvent evaporation method,interferon-a (IFN-a) microspheres were prepared with poly(lactide-co-glycolide) (PLGA) and their characteristics,such as morphology,drug loading,encapsula-tion efficiency,in vitro release and degradation were *** IFN-a microspheres were prepared by different viscosities from 0.1.–1.1. dL g-1.and concentrations between 5–25% of PLGA,which not only affected the drug loading and encapsulation efficiency of IFN-a microspheres,but also strongly influenced the in vitro *** smooth and porous surface,the drug loading and encapsulation efficiency of the microspheres prepared by 1.% 0.89 dL g-1.PLGA were 7.736% and 77.38%,*** DSC curve of microspheres indicated IFN-a was loaded inside the *** degradation of microspheres was homogeneous and the mass loss was over 80% in 6 *** release profile of microspheres showed a sustained fashion and the IFN-a released from microspheres maintained its bioactivity for 7 days.

关键词： Interferon-a microspheres poly(lactide-co-glycolide) viscosity concentration preparation

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

系统仿真学报 2008年第S1期20卷 176-179,186页

作者：朱军林珲林文实徐丙立西南交通大学土木工程学院测量工程系成都610031 香港中文大学太空与地球信息科学研究所中山大学环境科学与工程学院广州510275

重点开展基于虚拟地理环境的空气污染扩散模拟与交互操作研究,为城市空气污染的管理和时空动态模拟提供一个良好的可视化分析环境。以珠江三角洲空气污染为案例,建立虚拟地理环境原型系统,开展空气污染动态扩散模拟,进行实时交互查询与... 详细信息

重点开展基于虚拟地理环境的空气污染扩散模拟与交互操作研究,为城市空气污染的管理和时空动态模拟提供一个良好的可视化分析环境。以珠江三角洲空气污染为案例,建立虚拟地理环境原型系统,开展空气污染动态扩散模拟,进行实时交互查询与分析,实验结果证明,本文的方案能够逼真地模拟大气污染扩散过程,能较好地揭示城市群间空气污染的相互影响规律。

关键词：虚拟地理环境城市群空气污染动态模拟交互查询

在线全文

学校读者我要写书评

暂无评论

以扩展分区为核心的流程网分析方法

计算机工程与应用 2010年第10期46卷 48-50页

作者：刘显明李师贤李卫华梁文马勇江西省电力信息通讯有限公司技术部南昌330077 中山大学计算机科学系广州510275 广东工业大学计算机学院广州510096

业务流程网是一种用于业务流程建模的新工具。介绍了业务流程网基本概念后,提出一种用于业务流程网状态空间计算的新方法。该方法以自动机研究领域的分区方法为基础,为分区扩展成本信息,从而得到一种扩展分区,进而给出状态空间计算方法... 详细信息

业务流程网是一种用于业务流程建模的新工具。介绍了业务流程网基本概念后,提出一种用于业务流程网状态空间计算的新方法。该方法以自动机研究领域的分区方法为基础,为分区扩展成本信息,从而得到一种扩展分区,进而给出状态空间计算方法,最后证明了:对于有界的业务流程网来说,扩展分区的计算是可终止的,并且最小成本可达问题是可判定的。

关键词：扩展分区业务流程 Petri网状态空间计算

Green tea polyphenol epigallocatechin-3-gallate suppresses rat hepatic stellate cell invasion by inhibition of MMP-2 expression and its activation

在线全文

学校读者我要写书评

暂无评论

Acta Pharmacologica Sinica 2006年第12期27卷 1600-1607页

作者： Mao-chuan ZHEN Xiao-hui HUANG Qian WANG~2 Kai sun Yun-jian LIU Wen LI Long-juan ZHANG Liang-qi CAO Xi-ling CHEN {1. of Hepatobiliary Surgery,the First Affiliated Hospital of {1.,guangzhou 51.080,China departmentofHepatobiliarySurgery theFirstAffiliatedHospitalofSunYat-SenUniversityGuangzhou510080China

Aim:Epigallocatechin-3-gallate(EGCG)is the major component of green teapolyphenols,whose wide range of biological properties includes *** metalloproteinases(MMP)that participate in extracellular matrixdegradation are involved in the development of hepatic *** presentstudy investigates whether EGCG inhibits activation of the major gelatinase matrixmetalloproteinase-2(MMP-2)in rat hepatic stellate cells(HSC).Methods:Theexpression of MMP-2,tissue inhibitors of metalloproteinases-2(TIMP-2),andmembrane-type 1.MMP(MT1.MMP)was assessed by RT-PCR and Western ***-2 activity was evaluated by zymography and MT1.MMP activitywas assessed by an enzymatic *** migration was measured by a woundhealing assay and cell invasion was performed using Transwell cell ***:The expression of MMP-2 mRNA and protein in HSC wassubstantially reduced by EGCG *** treatment also reduced con-canavalin A(ConA)-induced activation of secreted MMP-2 and reduced MT1.MMP activity in a dose-dependent *** addition,EGCG inhibited eitherHSC migration or ***:The abilities of EGCG to suppress MMP-2 activation and HSC invasiveness suggest that EGCG may be useful in the treat-ment and prevention of hepatic fibrosis.

关键词： matrix metalloproteinase hepatic stellate cell green tea migration invasion

Comparative proteomic analysis of human osteosarcoma and SV40-im-mortalized normal osteoblastic cell lines

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 Pharmacologica Sinica 2007年第6期28卷 850-858页

作者： Qian-chen GUO~2,Jing-nan SHEN~(2,5),Song JIN~2,Jin WANG~2,Gang HUANG~2,Long-juan ZHANG~3,Jun-qiang YIN~2,Chang-yeZOU~2,Ming-tao LI~4~2 department of Orthopedic Surgery,~3 Laboratory Center of Surgery and ~4 proteomic Center,{1.,guangzhou 51.080,China departmentofOrthopedicSurgery SunYat-senUniversityGuangzhou510080China LaboratoryCenterofSurgery SunYat-senUniversityGuangzhou510080China ProteomicCenter SunYat-senUniversityGuangzhou510080China

Aim:Comparative proteomics provide a powerful approach in screening for alter-ations in protein levels and post-translational modifications that are associatedwith *** the present study,we aimed to identify candidate biomarkers todistinguish osteosarcoma (OS) cells from normal osteoblastic ***:Weemployed 3OS cell lines (U2OS,IOR/OS9,and SaOS-2),and used the SV40-immor-talized normal osteoblastic cell line (hFOB 1.1.) as the *** differentialprotein levels in OS and osteoblastic cells were identified using 2-D gel electro-phoresis followed by matrix-assisted laser desorption/ionization-time of flightmass spectrometry *** proteins of interest,the levels of which weresignificantly increased in OS cells,were further characterized by Western ***:Twenty-six proteins were identified,the expression level ofwhich was either significantly increased or decreased in the OS cells as comparedto the control *** expression level of the activator of 90 kDa shock proteinATPase homolog 1.(AHA1.,was enhanced 1..4-,24.1.,and 23.8-fold in SaOS-2,IOR/OS9,and U2OS cells,respectively,and the level of the stomatin-like protein 2(SLP-2) was increased by 1..4-and 7.8-fold in IOR/OS9 and U2OS cells,respectively,as compared to normal osteoblastic *** observations were confirmed byWestern blot ***:A differential proteomic analysis was suc-cessfully used to identify AHA 1.and SLP-2 that were significantly overproducedin OS cells as compared to normal osteoblastic cells,suggesting that those pro-teins among others may be effective biomarker candidates for the identification ofOS cells.

关键词： AHA1 differentially-produced protein osteosarcoma proteome SLP-2

Exon-by-exon Screening for RB Germline Mutations Using Heteroduplex-SSCP Analysis

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

眼科学报 1997年第1期13卷 5-11页

作者： Qingjiong Zhang, Kensei Minoda, Ruiping Zeng, Zhongyao Wu Xueshan Xiao, Shiqiang Li, Fengshen ZhangZhongshan Ophthalmic Center department of Medica Genetics{1. of Medical sciences , guangzhou 51.060 , Chinadepartment of Ophthalmology, Teikyo university Ichihara Hospital, Ichihara , Chiba 299 - 01. Japan. Zhongshan Ophthalmic Center Sun Yat-sen University of Medical Sciences Guangzhou 510060 China.

Objective: To disclose the nature of RBI germline mutations in Chinese and to develop a practical and effective way for mutational screening. Methods: Leukocyte DNA was prepared from 8 Chinese patients with hereditary retinoblastoma. PCR combined with nonisotopic heteroduplex-SSCP analysis was used to screen leukocyte DNA for RBI germline mutations, exon-by-exon, without the use of restriction endonuclease digestion. The mutations were finally identified by sequencing. In order to testify the effectiveness of this method, the same method was used to detect other 1. samples which have been previously analyzed by other methods. Results: Heterozygous germline mutations were detected in the leukocyte DNA of 6 out of 8 Chinese patients;G del/codon 46,T del/codon 1.1.,CAGAA del/condon 257 -258, GCAgta→GCAgca/donor of exon 1., C@T/codon 661. and C→T/codon 787. Heteroduplex-SSCP analysis may detect RBI germline mutations in 68% (1.7 25) unselected patients, which is more effective than SSCP(56%) or

关键词：成视网膜细胞瘤突变 SSCP 遗传因素非遗传因素