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   2364737篇
  免费   176853篇
  国内免费   4762篇
耳鼻咽喉   32165篇
儿科学   76069篇
妇产科学   62856篇
基础医学   350514篇
口腔科学   63970篇
临床医学   213997篇
内科学   459397篇
皮肤病学   51918篇
神经病学   186200篇
特种医学   88682篇
外国民族医学   502篇
外科学   355709篇
综合类   51391篇
现状与发展   17篇
一般理论   848篇
预防医学   183491篇
眼科学   54826篇
药学   177262篇
  31篇
中国医学   5751篇
肿瘤学   130756篇
  2021年   20097篇
  2019年   20222篇
  2018年   27832篇
  2017年   21026篇
  2016年   23421篇
  2015年   26670篇
  2014年   37332篇
  2013年   54999篇
  2012年   76217篇
  2011年   81109篇
  2010年   48059篇
  2009年   45330篇
  2008年   75630篇
  2007年   80451篇
  2006年   81325篇
  2005年   78793篇
  2004年   75021篇
  2003年   72276篇
  2002年   69864篇
  2001年   109167篇
  2000年   111904篇
  1999年   93973篇
  1998年   27291篇
  1997年   23951篇
  1996年   24253篇
  1995年   22910篇
  1994年   21104篇
  1993年   19826篇
  1992年   72121篇
  1991年   70187篇
  1990年   68510篇
  1989年   65747篇
  1988年   60384篇
  1987年   59193篇
  1986年   55273篇
  1985年   53059篇
  1984年   39329篇
  1983年   33407篇
  1982年   19873篇
  1979年   35880篇
  1978年   25653篇
  1977年   21232篇
  1976年   20335篇
  1975年   21816篇
  1974年   26151篇
  1973年   24802篇
  1972年   23200篇
  1971年   22037篇
  1970年   20247篇
  1969年   19315篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
33.
34.
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   
35.
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   
36.
37.
38.
<正>随着科技的进步,医疗技术的不断提高,使得诸多影像学检查在临床疾病诊断和治疗工作中发挥了重要作用。20世纪90年代末推出了数字X线成像(digital radiography,DR)成像系统,DR数字影像具有成像质量高,成像速度快,辐射剂量小等优点通过该系统,可以直接将X线信号转换为数字信号,既缩短了拍摄时间,同时由于自带显示系统,医生可以第一时间获得有关患者病情的清晰影像资料,这对于  相似文献   
39.
40.
Graefe's Archive for Clinical and Experimental Ophthalmology - The published online version contains mistake as the author's first name and last name have been interchanged as "Hild...  相似文献   
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