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   1422729篇
  免费   104644篇
  国内免费   3293篇
耳鼻咽喉   18477篇
儿科学   46619篇
妇产科学   41054篇
基础医学   201051篇
口腔科学   37747篇
临床医学   126280篇
内科学   285135篇
皮肤病学   33432篇
神经病学   117287篇
特种医学   53901篇
外国民族医学   464篇
外科学   210814篇
综合类   32758篇
现状与发展   3篇
一般理论   487篇
预防医学   110135篇
眼科学   31558篇
药学   98666篇
  38篇
中国医学   3350篇
肿瘤学   81410篇
  2021年   11061篇
  2019年   12127篇
  2018年   16637篇
  2017年   12719篇
  2016年   14320篇
  2015年   16031篇
  2014年   22592篇
  2013年   33411篇
  2012年   45425篇
  2011年   47951篇
  2010年   28178篇
  2009年   27060篇
  2008年   44333篇
  2007年   46844篇
  2006年   47396篇
  2005年   45870篇
  2004年   43759篇
  2003年   41711篇
  2002年   40207篇
  2001年   73018篇
  2000年   74550篇
  1999年   61579篇
  1998年   16996篇
  1997年   15437篇
  1996年   15587篇
  1995年   14797篇
  1994年   13402篇
  1993年   12589篇
  1992年   45856篇
  1991年   43500篇
  1990年   41516篇
  1989年   39568篇
  1988年   36199篇
  1987年   35360篇
  1986年   32875篇
  1985年   31286篇
  1984年   23839篇
  1983年   20029篇
  1982年   12214篇
  1981年   10786篇
  1979年   20712篇
  1978年   14585篇
  1977年   12093篇
  1976年   11370篇
  1975年   11624篇
  1974年   14000篇
  1973年   13539篇
  1972年   12643篇
  1971年   11471篇
  1970年   10914篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
In a prospective study, we sought to determine acceptability of linkage of administrative and clinical trial data among Canadian patients and Research Ethics Boards (REBs). The goal is to develop a more harmonized approach to data, with potential to improve clinical trial conduct through enhanced data quality collected at reduced cost and inconvenience for patients. On completion of the original LY.12 randomized clinical trial in lymphoma (NCT00078949), participants were invited to enrol in the Long-term Innovative Follow-up Extension (LIFE) component. Those consenting to do so provided comprehensive identifying information to facilitate linkage with their administrative data. We prospectively designed a global assessment of this innovative approach to clinical trial follow-up including rates of REB approval and patient consent. The pre-specified benchmark for patient acceptability was 80%. Of 16 REBs who reviewed the research protocol, 14 (89%) provided approval; two in Quebec declined due to small patient numbers. Of 140 patients invited to participate, 115 (82%, 95% CI 76 to 88%) from across 9 Canadian provinces provided consent and their full name, date of birth, health insurance number and postal code to facilitate linkage with their administrative data for long-term follow-up. Linkage of clinical trial and administrative data is feasible and acceptable. Further collaborative work including many stakeholders is required to develop an optimized secure approach to research. A more coordinated national approach to health data could facilitate more rapid testing and identification of new effective treatments across multiple jurisdictions and diseases from diabetes to COVID-19.  相似文献   
42.
43.
44.
45.
46.
Naunyn-Schmiedeberg's Archives of Pharmacology - Ochratoxin A (OTA) and aristolochic acid (AA) are toxins that can frequently contaminate cereals and cereals-based products. The present study...  相似文献   
47.
48.
49.
50.
Antibodies are molecules that exhibit diverse conformational changes on different timescales, and there is ongoing interest to better understand the relationship between antibody conformational dynamics and storage stability. Physical stability data for an IgG4 monoclonal antibody (mAb-D) were gathered through traditional forced degradation (temperature and stirring stresses) and accelerated stability studies, in the presence of different additives and solution conditions, as measured by differential scanning calorimetry, size exclusion chromatography, and microflow imaging. The results were correlated with hydrogen exchange mass spectrometry (HX-MS) data gathered for mAb-D in the same formulations. Certain parameters of the HX-MS data, including hydrogen exchange in specific peptide segments in the CH2 domain, were found to correlate with stabilization and destabilization of additives on mAb-D during thermal stress. No such correlations between mAb physical stability and HX-MS readouts were observed under agitation stress. These results demonstrate that HX-MS can be set up as a streamlined methodology (using minimal material and focusing on key peptide segments at key time points) to screen excipients for their ability to physically stabilize mAbs. However, useful correlations between HX-MS and either accelerated or real-time stability studies will be dependent on a particular mAb's degradation pathway(s) and the type of stresses used.  相似文献   
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