首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   10358篇
  免费   483篇
  国内免费   116篇
耳鼻咽喉   55篇
儿科学   249篇
妇产科学   300篇
基础医学   1134篇
口腔科学   138篇
临床医学   762篇
内科学   2588篇
皮肤病学   274篇
神经病学   1021篇
特种医学   413篇
外科学   1881篇
综合类   28篇
一般理论   1篇
预防医学   342篇
眼科学   141篇
药学   648篇
中国医学   27篇
肿瘤学   955篇
  2024年   16篇
  2023年   79篇
  2022年   235篇
  2021年   294篇
  2020年   187篇
  2019年   216篇
  2018年   289篇
  2017年   200篇
  2016年   264篇
  2015年   341篇
  2014年   420篇
  2013年   555篇
  2012年   853篇
  2011年   814篇
  2010年   539篇
  2009年   437篇
  2008年   709篇
  2007年   722篇
  2006年   643篇
  2005年   630篇
  2004年   600篇
  2003年   479篇
  2002年   453篇
  2001年   59篇
  2000年   46篇
  1999年   51篇
  1998年   91篇
  1997年   60篇
  1996年   61篇
  1995年   55篇
  1994年   63篇
  1993年   45篇
  1992年   44篇
  1991年   49篇
  1990年   34篇
  1989年   35篇
  1988年   32篇
  1987年   26篇
  1986年   28篇
  1985年   17篇
  1984年   33篇
  1983年   24篇
  1982年   16篇
  1981年   12篇
  1980年   12篇
  1979年   7篇
  1978年   12篇
  1977年   8篇
  1974年   8篇
  1969年   5篇
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
121.
122.
123.
124.
125.
Candida guilliermondii (teleomorph Meyerozyma guilliermondii) is an ascomycetous species belonging to the Saccharomycotina CTG clade which has been studied over the last 40 years due to its biotechnological interest, biological control potential and clinical importance. Such a wide range of applications in various areas of fundamental and applied scientific research has progressively made C. guilliermondii an attractive model for exploring the potential of yeast metabolic engineering as well as for elucidating new molecular events supporting pathogenicity and antifungal resistance. All these research fields now take advantage of the establishment of a useful molecular toolbox specifically dedicated to C. guilliermondii genetics including the construction of recipient strains, the development of selectable markers and reporter genes and optimization of transformation protocols. This area of study is further supported by the availability of the complete genome sequence of the reference strain ATCC 6260 and the creation of numerous databases dedicated to gene ontology annotation (metabolic pathways, virulence, and morphogenesis). These genetic tools and genomic resources represent essential prerequisites for further successful development of C. guilliermondii research in medical mycology and in biological control by facilitating the identification of the multiple factors that contribute to its pathogenic potential. These genetic and genomic advances should also expedite future practical uses of C. guilliermondii strains of biotechnological interest by opening a window into a better understanding of the biosynthetic pathways of valuable metabolites.  相似文献   
126.
127.
Tumor necrosis factor alpha (TNFα) in intestinal mucosa plays a key role in the inflammation characterizing Crohn’s disease (CD). Moreover, adhesion molecule syndecan-1 mediates the maintenance of mucosal integrity and supports tissue repair. Therefore, our aim in this study was to correlate simultaneous expression of TNFα and syndecan-1 in patients affected by CD. Biopsies from 10 patients with CD of large bowel and 10 subjects with irritable bowel syndrome (controls) were studied by immunohistochemical detection of both TNFα and syndecan-1 on successive serial sections. Overall labeling index (OLI) was indicated by the percentage of positive stromal (i.e., nonepithelial) cells/1000 counted in randomized fields, whereas selected labeling index (SLI) was represented by the simultaneous evaluation of both molecules in a same single selected field of each specimen. TNFα and syndecan-1 OLI were significantly higher in CD compared with controls, while SLI showed an inverse relationship between the molecules in CD which was not observed in controls. Epithelial syndecan-1 cytoplasmatic staining of superficial epithelium was associated with loss of basolateral staining in the crypts and high stromal TNFα in CD. In conclusion, TNFα and syndecan-1 expression is increased in the intestinal mucosa of patients with CD. However, the expression of the two molecules is inversely related when a single field is considered, these data supporting the possibility of a downregulation exerted by TNFα.  相似文献   
128.
129.
Clinical Oral Investigations - To assess dimensional changes following alveolar ridge preservation using bovine-derived xenograft with 10% collagen and collagen membrane compared to ridge...  相似文献   
130.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号