首页 | 官方网站   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   22313篇
  免费   5985篇
  国内免费   41篇
医药卫生   28339篇
  2024年   136篇
  2023年   1114篇
  2022年   407篇
  2021年   826篇
  2020年   1316篇
  2019年   602篇
  2018年   1262篇
  2017年   1308篇
  2016年   1575篇
  2015年   1541篇
  2014年   2131篇
  2013年   2434篇
  2012年   1115篇
  2011年   1030篇
  2010年   1353篇
  2009年   1731篇
  2008年   948篇
  2007年   760篇
  2006年   1066篇
  2005年   666篇
  2004年   562篇
  2003年   472篇
  2002年   431篇
  2001年   348篇
  2000年   316篇
  1999年   322篇
  1998年   366篇
  1997年   284篇
  1996年   261篇
  1995年   226篇
  1994年   172篇
  1993年   142篇
  1992年   130篇
  1991年   113篇
  1990年   121篇
  1989年   98篇
  1988年   77篇
  1987年   60篇
  1986年   71篇
  1985年   63篇
  1984年   56篇
  1983年   52篇
  1982年   22篇
  1981年   23篇
  1980年   29篇
  1979年   24篇
  1978年   20篇
  1977年   23篇
  1976年   21篇
  1975年   20篇
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
91.
92.
The World Wide Web creates new challenges and opportunities for medical educators. Prominent among these are the lack of consistent standards by which to evaluate web-based educational tools. We present the instrument that was used to review web-based innovations in medical education submissions to the 2003 Society of General Internal Medicine (SGIM) national meeting, and discuss the process used by the SGIM web-based clinical curriculum interest group to develop the instrument. The 5 highest-ranked submissions are summarized with commentary from the reviewers.  相似文献   
93.
This breakout session at the Academic Emergency Medicine 2006 Consensus Conference examined how baseline overcrowding impedes the ability of emergency departments to respond to sudden, unexpected surges in demand for patient care. Differences between daily and catastrophic surge were discussed, and the need to invoke a hospital-wide response to surge was explored.  相似文献   
94.
Acrochordons (skin tags) are often considered clinically insignificant cutaneous redundancies that should be removed and destroyed with no histopathologic analysis performed. One rarely finds another neoplasm within an acrochordon. We describe a patient with an acrochordon that contained a squamous cell carcinoma that had features resembling a keratoacanthoma. This is the first time to our knowledge that an invasive squamous cell carcinoma has been described within an acrochordon.  相似文献   
95.
Objectives: To validate the accuracy of using probabilistic linkage for matching de‐identified ambulance records to a state trauma registry. Methods: This was a retrospective cohort analysis. Three thousand nine hundred nineteen true matches between ambulance and state trauma registry data from 1998 to 2003 were identified by deterministic matching on trauma identification number and verified by human review. Two thousand thirty‐eight ambulance records from trauma patients not meeting criteria for a true match, and an identical number of trauma registry records randomly selected from the one local county served by a different EMS provider, were included as nonmatches. There were 17 variables considered for linkage, which included the following: age, gender, race, county, hospital, date, rural setting, call and arrival times, mechanism, penetrating injury, vital signs, intubation, and intoxication. Probabilistic linkage was used to link the two data sets, using seven different combinations of common variables (maximum, 17; minimum, 4). The sensitivity and specificity of identifying true matches and nonmatches (95% confidence intervals [95% CI]) were calculated for each combination of variables. Results: Using all 17 available variables, 3,766 of 3,919 true matches were appropriately linked (sensitivity, 96.1%; 95% CI = 95.4% to 96.7%), with eight mismatches (specificity, 99.6%; 95% CI = 99.2% to 99.8%). Sensitivity fell below 95% with < 15 variables; however, sensitivity was very dependent on the inclusion of variables with high discriminatory power. Specificity remained >98% regardless of the number of variables included. Conclusions: Probabilistic linkage is a valid method for matching ambulance records to a trauma registry without the use of patient identifiers; however, the sensitivity of identifying true matches is critically dependent on the number and type of common variables included in the analysis.  相似文献   
96.
97.
98.
99.
100.
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-23

京公网安备 11010802026262号