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   3246425篇
  免费   244935篇
  国内免费   5682篇
耳鼻咽喉   44725篇
儿科学   106221篇
妇产科学   89745篇
基础医学   473777篇
口腔科学   89791篇
临床医学   295753篇
内科学   626837篇
皮肤病学   72992篇
神经病学   260050篇
特种医学   121688篇
外国民族医学   905篇
外科学   487682篇
综合类   72050篇
现状与发展   15篇
一般理论   1198篇
预防医学   256905篇
眼科学   75759篇
药学   238753篇
  10篇
中国医学   6862篇
肿瘤学   175324篇
  2021年   25780篇
  2019年   26604篇
  2018年   36908篇
  2017年   27798篇
  2016年   31391篇
  2015年   35263篇
  2014年   50074篇
  2013年   75117篇
  2012年   102886篇
  2011年   109859篇
  2010年   65033篇
  2009年   61584篇
  2008年   102278篇
  2007年   108771篇
  2006年   109965篇
  2005年   106725篇
  2004年   102291篇
  2003年   98093篇
  2002年   94745篇
  2001年   150358篇
  2000年   154106篇
  1999年   129242篇
  1998年   37794篇
  1997年   33443篇
  1996年   33502篇
  1995年   31642篇
  1994年   29191篇
  1993年   27417篇
  1992年   99468篇
  1991年   96578篇
  1990年   93882篇
  1989年   90439篇
  1988年   83294篇
  1987年   81305篇
  1986年   76234篇
  1985年   73167篇
  1984年   54936篇
  1983年   46680篇
  1982年   28116篇
  1979年   50106篇
  1978年   35583篇
  1977年   29636篇
  1976年   28270篇
  1975年   30008篇
  1974年   36238篇
  1973年   34534篇
  1972年   32547篇
  1971年   30481篇
  1970年   28359篇
  1969年   26813篇
排序方式: 共有10000条查询结果,搜索用时 312 毫秒
41.
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   
42.
43.
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   
44.
45.
ABSTRACT

This project examined 55 picture books featuring transgender, gender expansive or genderqueer protagonists or narrators published between 2008 and 2018. The purpose of the study was to determine how this genre of children’s literature supports and challenges four gender assumptions: the gender binary, gender essentialism, sex/gender congruency and gender stability. Additionally, this critical analysis explored misgendering within this genre and themes of social rejection and acceptance. Protagonists and narrators were permitted a degree of gender nonconformity, however, the majority of picture books missed opportunities for a more complete exploration of gender possibilities.  相似文献   
46.
47.
48.
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   
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