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   1411111篇
  免费   115906篇
  国内免费   3342篇
耳鼻咽喉   18386篇
儿科学   46758篇
妇产科学   41141篇
基础医学   201170篇
口腔科学   37789篇
临床医学   126139篇
内科学   284607篇
皮肤病学   33726篇
神经病学   116990篇
特种医学   53877篇
外国民族医学   464篇
外科学   210736篇
综合类   32826篇
现状与发展   3篇
一般理论   487篇
预防医学   110085篇
眼科学   31643篇
药学   98873篇
  1篇
中国医学   3364篇
肿瘤学   81294篇
  2021年   11059篇
  2019年   11795篇
  2018年   16718篇
  2017年   12768篇
  2016年   14389篇
  2015年   16123篇
  2014年   22722篇
  2013年   33577篇
  2012年   45642篇
  2011年   48177篇
  2010年   28308篇
  2009年   27171篇
  2008年   44485篇
  2007年   46970篇
  2006年   47542篇
  2005年   45987篇
  2004年   43875篇
  2003年   41809篇
  2002年   40319篇
  2001年   73070篇
  2000年   74603篇
  1999年   61602篇
  1998年   17010篇
  1997年   15448篇
  1996年   15607篇
  1995年   14797篇
  1994年   13411篇
  1993年   12601篇
  1992年   45861篇
  1991年   43501篇
  1990年   41527篇
  1989年   39578篇
  1988年   36204篇
  1987年   35376篇
  1986年   32881篇
  1985年   31293篇
  1984年   23835篇
  1983年   20036篇
  1982年   12215篇
  1981年   10784篇
  1979年   20709篇
  1978年   14585篇
  1977年   12095篇
  1976年   11368篇
  1975年   11622篇
  1974年   13993篇
  1973年   13536篇
  1972年   12638篇
  1971年   11476篇
  1970年   10912篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
21.
Introduction: The Hedgehog (HH) pathway constitutes a collection of signaling molecules which critically influence embryogenesis. In adults, however, the HH pathway remains integral to the proliferation, maintenance, and apoptosis of adult stem cells including hematopoietic stem cells.

Areas covered: We discuss the current understanding of the HH pathway as it relates to normal hematopoiesis, the pathology of acute myeloid leukemia (AML), the rationale for and data from combination therapies including HH pathway inhibitors, and ultimately the prospects that might offer promise in targeting this pathway in AML.

Expert opinion: Efforts to target the HH pathway have been focused on impeding this disposition and restoring chemosensitivity to conventional myeloid neoplasm therapies. The year 2018 saw the first approval of a HH pathway inhibitor (glasdegib) for AML, though for an older population and in combination with an uncommonly-used therapy. Several other clinical trials with agents targeting modulators of HH signaling in AML and MDS are underway. Further study and understanding of the interplay between the numerous aspects of HH signaling and how it relates to the augmented survival of AML will provide a more reliable substrate for therapeutic strategies in patients with this poor-risk disease.  相似文献   

22.
23.
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   
24.
25.
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   
26.
27.
28.
29.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   
30.
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