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81.
健康人肝组织麦胚凝集素亲和型糖蛋白表达谱分析   总被引:1,自引:0,他引:1  
目的分析健康人肝组织麦胚凝集素(wheatgermagglutinin,WGA)亲和型糖蛋白表达谱。方法从30例健康人肝组织混合样本的总蛋白中用WGA凝集素亲和层析分离纯化糖蛋白,再利用双向电泳结合SYPRO Ruby荧光染色进一步分离WGA亲和型糖蛋白。目的蛋白质点经质谱鉴定后对其进行生物信息学分析及功能分类。结果初步建立WGA亲和型糖蛋白的双向电泳图谱,图谱均点数为(650±50)个,质谱鉴定并去冗余共获116个蛋白。经生物信息学分析104个蛋白具有不同程度的N糖基化位点,最后按Gene Ontology的分类原则进行功能分类。结论凝集素亲和层析结合双向电泳荧光染色、质谱鉴定是一种高通量的检测方法,WGA亲和型糖蛋白表达谱的初步构建为后续研究奠定了基础。  相似文献   
82.
目的 从噬菌体展示随机肽库中筛选与内毒素结合的多肽序列,并进行鉴定.方法 以内毒素脂多糖(lipopolysaccharide,LPS)为靶分子对噬菌体展示随机十二肽库进行4轮亲和筛选,获得与LPS结合的噬菌体克隆,应用结合实验和克隆斑抑制实验进一步确证.挑选结合力强的克隆进行DNA测序,推导出呈现的多肽序列,应用生物信息学软件进行多肽序列分析和同源性分析.结果 经4轮亲和筛选从噬菌体展示随机十二肽库中筛选获得了86个克隆,挑选12个结合力强的克隆进行DNA序列测序及生物信息学分析,结合本项目组的噬菌体展示随机七肽库筛选结果推导出呈现的多肽序列为HWQWPHWSPPP(命名为P11肽).检索相关数据库发现此肽序列未被申请专利,体内约908种蛋白与其结构相匹配,其中包含有与LPS相互作用的位点.结论 通过对噬菌体展示随机肽库的淘选,获得与LPS结合的高亲和性多肽,为进一步以这些多肽为先导物进行定向进化研究提供了实验依据和结构基础.  相似文献   
83.
The purpose of this study was to explore the differentially expressed genes in lymph-node cells (LNC) of lymphomas and reactive lymph node hyperplasia, and to perform an initial bioinformatic analysis on a novel gene, KIAA0372, which is highly expressed in the LNC of lymphomas. mRNA extracted from LNC of lymphomas and reactive lymph node hyperplasia were respectively marked with biotin and hybridized with Gene Expression Chips, resulting in differentially expressed genes. Initial bioinformatic analysis was then performed on a novel gene named KIAA0372, whose function has not yet been explored. Its structure and genomic location, its product’s physical and chemical properties, subcellular localization and functional domains, were also predicted. Further, a systematic evolution analysis was performed on similar proteins from among several species. Using Gene Expression Chips, many differentially expressed genes were uncovered. Efficient bioinformatic analysis has fundamentally determined that KIAA0372 is an extracellular protein which may be involved in TGF-β signaling. Microarray is an efficient and high throughput strategy for detection of differentially expressed genes. And KIAA0372 is thought to be a potential target for tumor research using bioinformatic analysis.  相似文献   
84.
亓涛  姚成  郑磊  王前 《中国现代医学杂志》2006,16(24):3712-3715
目的 以筛选宫颈癌相关IL-18基因SNP位点为例,探讨筛选疾病相关SNP位点的生物信息学策略,并以实验验证.方法 使用SNPper软件从公共数据库dbSNP获得IL-18调控区和编码区的SNPs数据,使用PARSESNP软件进行筛选和分析编码区SNPs是否对基因表达产物产生影响;使用转录因子结合部位预测软件分析调控区SNPs是否对基因转录表达水平产生影响.然后通过病例-对照研究,使用直接测序法验证生物信息学方法结果的有效性.结果 生物信息学策略分析得到3个SNP位点(rs1946518、rs360719和rs187238),预测这些位点可能影响IL-18的转录表达水平,从而影响机体对肿瘤的抵抗作用.病例对照研究直接测序法分析,rs1946518和rs360719与宫颈癌相关;rs187238与宫颈癌无关联.结论 生物信息学策略分析疾病相关SNP位点,虽然存在假阳性等缺点,但仍然廉价可行,可以为疾病与基因关联性研究提供很有价值的信息.  相似文献   
85.
OBJECTIVE To analyze coding SNPs of the HLA-DQA1 gene involved in susceptibility for cervical cancer by a bioinformatics approach, and to choose some SNPs that may have an association with cervical cancer.METHODS By a SNPper tool we extracted SNPs from a public database (dbSNP), exporting them in FASTA formats suitable for subsequent use.Then we used PARSESNP as a tool for the analysis of the cSNPs.RESULTS In the cSNPs of the HLA-DQA1 gene, we find that rs9272693and rs9272703, are made up of missense mutations which convert a codon for one amino acid into a codon for a different amino acid. We chose a PSSM Difference >10 as a lower level for the scores of changes predicted to be deldterious.CONCLUSION We used a bioinformatics approach for cSNPs analysis of the HLA-DQA1 gene. This method can select the variants in a conserved region, and give a PSSM Difference score. But the results need to be verified in cervical cancer patients and a control population.  相似文献   
86.
建立我国现代中药质量标准体系的研究   总被引:5,自引:0,他引:5  
建立创新并具有独立知识产权的中药质量标准体系是开展我国自主医药研究和生产的关键之一。创建中药质量标准体系应遵循以下原则:应能体现中医药理论的特性;应能体现中药的物质基础是有效化合物群;要有利于中药专利的申请;应能体现与时俱进。通过中药指纹图谱的信息获取、信息处理和信息挖掘三方面内容的研究,开展指纹图谱信息与药效活性信息相关性研究,可实现中药化学指纹图谱向中药药效组分指纹图谱的转化,形成中药组效学研究体系。以中药药效组分指纹图谱结合指标成分定量为核心技术和基础的中药质量标准体系的建立,必将增强我国中药领域的自主创新能力。  相似文献   
87.
目的了解ZBTB5基因的序列和表达特征。方法运用生物信息学方法分析该基因的序列特征和染色体定位,分子生物学方法分析其表达特征和亚细胞定位。结果ZBTB5基因的N末端含一个BTB结构域,C末端含2个C2H2锌指结构域;根据人类基因组序列数据库搜索,将ZBTB5基因定位在人类基因组第9染色体上。Northern杂交结果表明,ZBTB5基因在不同组织中表达差异明显。免疫胶体金技术显示该蛋白定位于细胞核。结论该基因可能是一个转录因子。  相似文献   
88.
目的:获得尘螨变应原Der f 2基因及其生物信息学资料.方法:提取粉尘螨总RNA,RT-PCR合成Der f 2的cDNA片段,回收PCR产物并连接至pMD19-T simple,经测序验证后亚克隆入表达载体pET-28a( ),转化大肠杆菌感受态细胞后提取质粒,双酶切鉴定.用ExPaSy,EBI,NCBI网站的在线软件对测序结果进行分析.结果:RT-PCR扩增获得了Der f 2 cDNA片段,酶切、电泳结果表明克隆和亚克隆获得成功.与参考序列相比,测序结果多了87 bp(77~163),但Blastn发现中国广州和德国Reinbek报道的序列中也含此87bp.同源性、相似性、序列比对及分子进化分析提示,该序列与中国广州和德国Reinbek报道的序列亲缘关系较近.推测该变应原由176个氨基酸组成,与附睾分泌蛋白E1具有同源性,信号肽位于1~17aa处,在6~24aa处有一跨膜螺旋.二级结构由a-螺旋(16.57%),延伸链(32.57%)和随机卷曲(50.86%)组成.结论:获得了粉尘螨变应原Der f 2编码基因及其分子特征,为进一步生产基因工程变应原用于临床诊治变态反应性疾病奠定了基础.  相似文献   
89.
The Human Gene Mutation Database (HGMD) constitutes a comprehensive core collection of data on germ-line mutations in nuclear genes underlying or associated with human inherited disease (www.hgmd.org). Data catalogued includes: single base-pair substitutions in coding, regulatory and splicing-relevant regions; micro-deletions and micro-insertions; indels; triplet repeat expansions as well as gross deletions; insertions; duplications; and complex rearrangements. Each mutation is entered into HGMD only once in order to avoid confusion between recurrent and identical-by-descent lesions. By March 2003, the database contained in excess of 39,415 different lesions detected in 1,516 different nuclear genes, with new entries currently accumulating at a rate exceeding 5,000 per annum. Since its inception, HGMD has been expanded to include cDNA reference sequences for more than 87% of listed genes, splice junction sequences, disease-associated and functional polymorphisms, as well as links to data present in publicly available online locus-specific mutation databases. Although HGMD has recently entered into a licensing agreement with Celera Genomics (Rockville, MD), mutation data will continue to be made freely available via the Internet.  相似文献   
90.
Lasko P 《Clinical genetics》2002,62(5):358-367
Approximately three-quarters of human disease loci have counterparts in the fruit fly Drosophila melanogaster. This model organism is therefore extremely valuable for using to understand the role of these loci in normal development, and for unravelling genetic pathways in which these loci take part. Important advantages for Drosophila in such studies are its completed genome, the unparalleled collection of mutations already in existence, the relative ease in which new mutations can be generated, the existence of convenient techniques for inactivating or overexpressing genes in dispensable tissues that are easily observed and measured, and the ability to readily carry out second-site modifier genetics. Recent work in Drosophila on the insulin-signaling pathway, a pathway of profound clinical importance, is reviewed as an illustration of how such research can provide fundamental insights into the functions of this pathway in regulating growth and development. Moreover, Drosophila research is now identifying heretofore unknown regulators of insulin signaling, as well as indicating novel functions for this pathway in suppressing benign tumor formation and regulating life span.  相似文献   
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