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   1296473篇
  免费   85617篇
  国内免费   3277篇
耳鼻咽喉   17292篇
儿科学   44675篇
妇产科学   36649篇
基础医学   185773篇
口腔科学   37227篇
临床医学   111029篇
内科学   252756篇
皮肤病学   30542篇
神经病学   100060篇
特种医学   50662篇
外国民族医学   385篇
外科学   190010篇
综合类   25364篇
一般理论   409篇
预防医学   108244篇
眼科学   29992篇
药学   93860篇
  5篇
中国医学   2737篇
肿瘤学   67696篇
  2019年   9929篇
  2018年   18195篇
  2017年   14529篇
  2016年   14898篇
  2015年   17624篇
  2014年   21175篇
  2013年   29805篇
  2012年   46120篇
  2011年   44200篇
  2010年   24931篇
  2009年   23902篇
  2008年   38183篇
  2007年   41001篇
  2006年   41423篇
  2005年   47253篇
  2004年   47424篇
  2003年   41798篇
  2002年   36001篇
  2001年   54100篇
  2000年   53913篇
  1999年   47851篇
  1998年   12204篇
  1997年   10661篇
  1996年   10789篇
  1995年   10380篇
  1994年   9603篇
  1992年   39126篇
  1991年   38423篇
  1990年   38087篇
  1989年   36472篇
  1988年   33446篇
  1987年   33265篇
  1986年   31255篇
  1985年   29795篇
  1984年   22040篇
  1983年   18493篇
  1982年   10443篇
  1979年   20907篇
  1978年   14709篇
  1977年   12391篇
  1976年   11586篇
  1975年   12894篇
  1974年   15816篇
  1973年   15062篇
  1972年   14098篇
  1971年   13287篇
  1970年   12338篇
  1969年   11636篇
  1968年   10869篇
  1967年   9817篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
Journal of Immigrant and Minority Health - COVID-19 has disproportionally affected underrepresented minorities (URM) and low-income immigrants in the United States. The aim of the study is to...  相似文献   
13.
14.
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   
15.
16.
Introduction: Pharmacovigilance is essential to monitoring the safety profiles of authorized medicines. Compared with small-molecule drugs, biological drugs are more complex, more susceptible to structural variability due to manufacturing processes, and have the potential to induce immune-related reactions, underscoring the importance of safety monitoring for these products. Although highly similar to reference products, biosimilars are not expected to be structurally identical. For these reasons, proper reporting of potential adverse drug reactions (ADRs) using distinguishable names and batch numbers is essential for accurate tracing of all biological drugs. To address the need for robust pharmacovigilance, the European Parliament and Council of the European Union provided legislation regarding pharmacovigilance of biologics in 2010.

Areas covered: This narrative review examines the current state of pharmacovigilance for biologics in the European Union (EU) and discusses relevant information on pharmacovigilance of biosimilars, the current EU pharmacovigilance system, and areas that could be improved.

Expert opinion: Although steps have been taken to improve pharmacovigilance of biologics in the EU, several enhancements can still be made, including additional training for healthcare professionals on ADR reporting, the use of 2D barcodes that enhance traceability, and an open discussion of potentially missed opportunities in the pharmacovigilance of biosimilars.  相似文献   

17.
18.
19.
20.
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