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   3246345篇
  免费   244940篇
  国内免费   5672篇
耳鼻咽喉   44732篇
儿科学   106234篇
妇产科学   89722篇
基础医学   473753篇
口腔科学   89783篇
临床医学   295767篇
内科学   626814篇
皮肤病学   73005篇
神经病学   260049篇
特种医学   121667篇
外国民族医学   905篇
外科学   487580篇
综合类   72060篇
现状与发展   15篇
一般理论   1198篇
预防医学   256929篇
眼科学   75802篇
药学   238732篇
  10篇
中国医学   6860篇
肿瘤学   175340篇
  2021年   25756篇
  2019年   26587篇
  2018年   36908篇
  2017年   27790篇
  2016年   31377篇
  2015年   35243篇
  2014年   50052篇
  2013年   75095篇
  2012年   102844篇
  2011年   109820篇
  2010年   65016篇
  2009年   61563篇
  2008年   102265篇
  2007年   108769篇
  2006年   109941篇
  2005年   106716篇
  2004年   102282篇
  2003年   98104篇
  2002年   94755篇
  2001年   150364篇
  2000年   154128篇
  1999年   129251篇
  1998年   37793篇
  1997年   33441篇
  1996年   33498篇
  1995年   31634篇
  1994年   29191篇
  1993年   27415篇
  1992年   99462篇
  1991年   96583篇
  1990年   93886篇
  1989年   90444篇
  1988年   83300篇
  1987年   81319篇
  1986年   76245篇
  1985年   73187篇
  1984年   54945篇
  1983年   46689篇
  1982年   28125篇
  1979年   50115篇
  1978年   35587篇
  1977年   29645篇
  1976年   28271篇
  1975年   30018篇
  1974年   36258篇
  1973年   34544篇
  1972年   32553篇
  1971年   30486篇
  1970年   28356篇
  1969年   26818篇
排序方式: 共有10000条查询结果,搜索用时 15 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