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   3529412篇
  免费   305410篇
  国内免费   14201篇
耳鼻咽喉   48074篇
儿科学   112774篇
妇产科学   92560篇
基础医学   563192篇
口腔科学   94009篇
临床医学   317935篇
内科学   630152篇
皮肤病学   93816篇
神经病学   305410篇
特种医学   138585篇
外国民族医学   490篇
外科学   542693篇
综合类   107675篇
现状与发展   24篇
一般理论   2342篇
预防医学   295238篇
眼科学   80875篇
药学   242773篇
  19篇
中国医学   10495篇
肿瘤学   169892篇
  2021年   55275篇
  2020年   35253篇
  2019年   58281篇
  2018年   71798篇
  2017年   54500篇
  2016年   60413篇
  2015年   74167篇
  2014年   108531篇
  2013年   173770篇
  2012年   99886篇
  2011年   100513篇
  2010年   118288篇
  2009年   122721篇
  2008年   87394篇
  2007年   91102篇
  2006年   101616篇
  2005年   96882篇
  2004年   98164篇
  2003年   88698篇
  2002年   78110篇
  2001年   118244篇
  2000年   111684篇
  1999年   107671篇
  1998年   66819篇
  1997年   64376篇
  1996年   62185篇
  1995年   57608篇
  1994年   51575篇
  1993年   48124篇
  1992年   74249篇
  1991年   69934篇
  1990年   65672篇
  1989年   64464篇
  1988年   59431篇
  1987年   58112篇
  1986年   54650篇
  1985年   54455篇
  1984年   49547篇
  1983年   45108篇
  1982年   42209篇
  1981年   39595篇
  1980年   37284篇
  1979年   40258篇
  1978年   35596篇
  1977年   32324篇
  1976年   29654篇
  1975年   27952篇
  1974年   29035篇
  1973年   28046篇
  1972年   26241篇
排序方式: 共有10000条查询结果,搜索用时 296 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