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   4459071篇
  免费   358950篇
  国内免费   15319篇
耳鼻咽喉   62102篇
儿科学   143926篇
妇产科学   118224篇
基础医学   678406篇
口腔科学   121713篇
临床医学   403229篇
内科学   812137篇
皮肤病学   110585篇
神经病学   369028篇
特种医学   175831篇
外国民族医学   888篇
外科学   684766篇
综合类   129565篇
现状与发展   23篇
一般理论   2575篇
预防医学   365003篇
眼科学   106253篇
药学   313571篇
  23篇
中国医学   12647篇
肿瘤学   222845篇
  2021年   56251篇
  2020年   35807篇
  2019年   59049篇
  2018年   74648篇
  2017年   56739篇
  2016年   62841篇
  2015年   75948篇
  2014年   110364篇
  2013年   176055篇
  2012年   123288篇
  2011年   128335篇
  2010年   126448篇
  2009年   127644篇
  2008年   114960篇
  2007年   122535篇
  2006年   130783篇
  2005年   125505篇
  2004年   126963篇
  2003年   116731篇
  2002年   106096篇
  2001年   173733篇
  2000年   169553篇
  1999年   155092篇
  1998年   73220篇
  1997年   68486篇
  1996年   66373篇
  1995年   61806篇
  1994年   55968篇
  1993年   51907篇
  1992年   112398篇
  1991年   108219篇
  1990年   103541篇
  1989年   100740篇
  1988年   92784篇
  1987年   90809篇
  1986年   85540篇
  1985年   83638篇
  1984年   69491篇
  1983年   61591篇
  1982年   48498篇
  1981年   45259篇
  1980年   42300篇
  1979年   59022篇
  1978年   47209篇
  1977年   42296篇
  1976年   38970篇
  1975年   39117篇
  1974年   42767篇
  1973年   40997篇
  1972年   38290篇
排序方式: 共有10000条查询结果,搜索用时 718 毫秒
101.
102.
103.
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   
104.
105.
106.
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   
107.
We review the spectrum of cutaneous disorders associated with inflammatory and neoplastic plasmacytic pathology. Because plasma cells are derived from B‐lymphocytes our overview includes discussion of certain lymphoplasmacytic proliferations. It is structured along histopathological lines, addressing conditions characterized by (a) cutaneous plasma cell infiltrates, (b) deposits of plasma cell products or their derivatives in the skin and (c) miscellaneous, poorly understood cutaneous complications of plasmacytic disorders. Lesions arising primarily in the skin and those due to cutaneous involvement by multisystem disorders are addressed. The range includes a spectrum of tumefactive and circulatory manifestations. We highlight key clinical and pathological features of the different conditions and outline recent advances in our understanding of these entities. By emphasizing the dermatopathological characteristics of this spectrum of disorders we hope to hone the diagnostic accuracy of practitioners in the field.  相似文献   
108.
109.
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   
110.
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