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   3924788篇
  免费   298549篇
  国内免费   6727篇
耳鼻咽喉   56439篇
儿科学   124549篇
妇产科学   105534篇
基础医学   565213篇
口腔科学   112353篇
临床医学   361155篇
内科学   750689篇
皮肤病学   83432篇
神经病学   319487篇
特种医学   151324篇
外国民族医学   1277篇
外科学   590397篇
综合类   89553篇
现状与发展   13篇
一般理论   1601篇
预防医学   317369篇
眼科学   93800篇
药学   294073篇
  14篇
中国医学   7544篇
肿瘤学   204248篇
  2018年   42157篇
  2017年   31988篇
  2016年   35687篇
  2015年   40308篇
  2014年   57647篇
  2013年   87703篇
  2012年   119274篇
  2011年   126807篇
  2010年   75421篇
  2009年   71374篇
  2008年   119379篇
  2007年   127184篇
  2006年   128402篇
  2005年   124790篇
  2004年   120053篇
  2003年   115521篇
  2002年   113150篇
  2001年   175013篇
  2000年   180529篇
  1999年   152760篇
  1998年   45578篇
  1997年   40424篇
  1996年   40012篇
  1995年   38319篇
  1994年   35728篇
  1993年   33545篇
  1992年   121575篇
  1991年   118609篇
  1990年   115271篇
  1989年   111044篇
  1988年   102916篇
  1987年   101064篇
  1986年   95424篇
  1985年   91692篇
  1984年   69243篇
  1983年   59080篇
  1982年   35791篇
  1981年   32040篇
  1979年   64959篇
  1978年   46071篇
  1977年   38665篇
  1976年   36869篇
  1975年   39084篇
  1974年   47649篇
  1973年   45368篇
  1972年   42878篇
  1971年   40116篇
  1970年   37354篇
  1969年   35153篇
  1968年   32289篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
MicroRNAs (miRNAs) play important roles in prostate cancer development. However, it remains unclear how individual miRNAs contribute to the initiation and progression of prostate cancer. Here we show that a basal layer‐enriched miRNA is required for prostate tumorigenesis. We identify miR‐205 as the most highly expressed miRNA and enriched in the basal cells of the prostate. Although miR‐205 is not required for normal prostate development and homeostasis, genetic deletion of miR‐205 in a Pten null tumor model significantly compromises tumor progression and does not promote metastasis. In Pten null basal cells, loss of miR‐205 attenuates pAkt levels and promotes cellular senescence. Furthermore, although overexpression of miR‐205 in prostate cancer cells with luminal phenotypes inhibits cell growth in both human and mouse, miR‐205 has a minimal effect on the growth of a normal human prostate cell line. Taken together, we have provided genetic evidence for a requirement of miR‐205 in the progression of Pten null‐induced prostate cancer.  相似文献   
44.
45.
Secondary tricuspid regurgitation (TR) caused by right ventricular enlargement in the setting of left heart disease/pulmonary hypertension has been well described. In contrast, that associated with right atrial enlargement—atrial functional TR (AF‐TR)—remains largely underappreciated. AF‐TR most often occurs in the setting of lone atrial fibrillation, although it is also seen in its absence (idiopathic AF‐TR). Several recent studies have found that the prevalence, hemodynamic significance, and prognosis of AF‐TR are not inconsequential, suggesting increased physician awareness of this novel clinical entity is warranted. This article discusses the pathogenesis, echocardiographic findings, and treatment of this underappreciated cause of secondary TR.  相似文献   
46.
47.
BackgroundThe aim of this study was to estimate the prevalence of dental prosthetic treatment and to investigate the demographic, social, economic and medical factors associated with the use of fixed and removable dentures in a representative sample of adults living in France.MethodsThe data were obtained from the 2002–2003 Decennial Health Survey, a cross-sectional study of a representative sample of the population living in France, which included 29,679 adults. Information was collected by interview. The variables collected were fixed denture, removable denture, age, gender, number of children, area of residence, nationality, educational attainment, family social status, employment status, annual household income per capita, supplementary insurance, chronic disease, eyesight problems/glasses, hearing problems/hearing aids. Multinomial logistic regression models were used to study the relationship between prosthetic treatment and demographic, socioeconomic and medical characteristics unadjusted, adjusted for age and adjusted for all the characteristics.ResultsThe prevalence of prosthetic treatment was 34.6% (95% confidence interval (CI): [34.1; 35.2]) for fixed prosthetic dentures and 13.8% (95% CI: [13.4; 14.2]) for removable prosthetic dentures. We showed a gradient between educational attainment and removable dentures; the odds ratio adjusted for all the variables (aOR) associated with no or primary education compared to post-secondary education was 2.56; 95% CI: [2.09; 3.13]. When annual household income per capita was low, subjects were less likely to report fixed dentures (aOR = 0.68; 95% CI: [0.62; 0.75]) than those with high annual household income per capita. Individuals without insurance less often reported fixed dentures than those with private insurance. Those reporting chronic disease were less likely to report fixed dentures (aOR = 0.87; 95% CI: [0.79; 0.95]) but more likely to report removable dentures (aOR = 1.29; 95% CI: [1.17; 1.43]) than those without chronic disease.ConclusionThis study reveals social, economic and medical inequalities in fixed and removable prosthetic treatment among adults in France.  相似文献   
48.
49.
50.
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