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   74363篇
  免费   7129篇
  国内免费   201篇
耳鼻咽喉   620篇
儿科学   2776篇
妇产科学   1950篇
基础医学   10991篇
口腔科学   1574篇
临床医学   9951篇
内科学   14491篇
皮肤病学   1395篇
神经病学   7645篇
特种医学   2082篇
外科学   7703篇
综合类   624篇
现状与发展   1篇
一般理论   77篇
预防医学   8273篇
眼科学   1049篇
药学   4737篇
  2篇
中国医学   99篇
肿瘤学   5653篇
  2023年   671篇
  2022年   752篇
  2021年   1951篇
  2020年   1465篇
  2019年   2113篇
  2018年   2460篇
  2017年   2022篇
  2016年   2131篇
  2015年   2191篇
  2014年   2799篇
  2013年   4127篇
  2012年   5593篇
  2011年   5798篇
  2010年   3144篇
  2009年   2625篇
  2008年   4643篇
  2007年   4789篇
  2006年   4531篇
  2005年   4403篇
  2004年   4159篇
  2003年   3906篇
  2002年   3444篇
  2001年   913篇
  2000年   868篇
  1999年   757篇
  1998年   804篇
  1997年   652篇
  1996年   596篇
  1995年   584篇
  1994年   503篇
  1993年   455篇
  1992年   446篇
  1991年   381篇
  1990年   382篇
  1989年   343篇
  1988年   323篇
  1987年   267篇
  1986年   288篇
  1985年   286篇
  1984年   299篇
  1983年   252篇
  1982年   257篇
  1981年   250篇
  1980年   220篇
  1979年   196篇
  1978年   161篇
  1977年   131篇
  1976年   126篇
  1975年   127篇
  1974年   118篇
排序方式: 共有10000条查询结果,搜索用时 859 毫秒
1.
2.
Tamoxifen prevents recurrence of breast cancer and is suggested for preventive risk-reducing therapy. Tamoxifen reduces mammographic density, a proxy for therapy response, but little is known about its effects in remodelling normal breast tissue. Our study, a substudy within the double-blinded dose-determination trial KARISMA, investigated tamoxifen-specific changes in breast tissue composition and histological markers in healthy women. We included 83 healthy women randomised to 6 months daily intake of 20, 10, 5, 2.5, 1 mg of tamoxifen or placebo. The groups were combined to “no dose” (0-1 mg), “low-dose” (2.5-5 mg) or “high-dose” (10-20 mg) of tamoxifen. Ultrasound-guided biopsies were collected before and after tamoxifen exposure. In each biopsy, epithelial, stromal and adipose tissues was quantified, and expression of epithelial and stromal Ki67, oestrogen receptor (ER) and progesterone receptor (PR) analysed. Mammographic density using STRATUS was measured at baseline and end-of-tamoxifen-exposure. We found that different doses of tamoxifen reduced mammographic density and glandular-epithelial area in premenopausal women and associated with reduced epithelium and increased adipose tissue. High-dose tamoxifen also decreased epithelial ER and PR expressions in premenopausal women. Premenopausal women with the greatest reduction in proliferation also had the greatest epithelial reduction. In postmenopausal women, high-dose tamoxifen decreased the epithelial area with no measurable density decrease. Tamoxifen at both low and high doses influences breast tissue composition and expression of histological markers in the normal breast. Our findings connect epithelial proliferation with tissue remodelling in premenopausal women and provide novel insights to understanding biological mechanisms of primary prevention with tamoxifen.  相似文献   
3.
4.
5.
6.
ContextIt is especially important that patients are well informed when making high-stakes, preference-sensitive decisions like those on the Physician Orders for Life-Sustaining Treatment (POLST) form. However, there is currently no way to easily evaluate whether patients understand key concepts when making these important decisions.ObjectivesTo develop a POLST knowledge survey.MethodsExpert (n = 62) ratings of key POLST facts were used to select items for a POLST knowledge survey. The survey was administered to nursing facility residents (n = 97) and surrogate decision-makers (n = 112). A subset (n = 135) were re-administered the survey after a standardized advance care planning discussion to assess the scale's responsiveness to change.ResultsThe 19-item survey demonstrated adequate reliability (α = 0.72.). Residents' scores (x = 11.4, standard deviation 3.3) were significantly lower than surrogate scores (x = 14.7, standard deviation 2.5) (P < 0.001). Scores for both groups increased significantly after administration of a standardized advance care planning discussion (P < 0.001). Although being a surrogate, age, race, education, cognitive functioning, and health literacy were significantly associated with higher POLST Knowledge Survey scores in univariate analyses, only being a surrogate (P < 0.001) and being white (P = 0.028) remained significantly associated with higher scores in multivariate analyses.ConclusionThe 19-item POLST Knowledge Survey demonstrated adequate reliability and responsiveness to change. Findings suggest the survey could be used to identify knowledge deficits and provide targeted education to ensure adequate understanding of key clinical decisions when completing POLST.  相似文献   
7.
8.
9.
Annals of Nuclear Medicine - The Response Evaluation Criteria In Solid Tumors (RECIST) is the most used radiological method for evaluating response after peptide receptor radionuclide therapy...  相似文献   
10.
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