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   46937篇
  免费   3939篇
  国内免费   110篇
医药卫生   50986篇
  2024年   41篇
  2023年   397篇
  2022年   333篇
  2021年   1265篇
  2020年   941篇
  2019年   1398篇
  2018年   1538篇
  2017年   1204篇
  2016年   1333篇
  2015年   1403篇
  2014年   1788篇
  2013年   2633篇
  2012年   3679篇
  2011年   3786篇
  2010年   2076篇
  2009年   1841篇
  2008年   3061篇
  2007年   3150篇
  2006年   3091篇
  2005年   2912篇
  2004年   2825篇
  2003年   2599篇
  2002年   2337篇
  2001年   373篇
  2000年   275篇
  1999年   322篇
  1998年   523篇
  1997年   394篇
  1996年   352篇
  1995年   341篇
  1994年   272篇
  1993年   269篇
  1992年   201篇
  1991年   167篇
  1990年   151篇
  1989年   119篇
  1988年   130篇
  1987年   90篇
  1986年   99篇
  1985年   102篇
  1984年   100篇
  1983年   100篇
  1982年   125篇
  1981年   121篇
  1980年   99篇
  1979年   64篇
  1978年   67篇
  1977年   48篇
  1976年   47篇
  1972年   36篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
1.
2.
3.
4.
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   
5.
6.
7.
8.
9.
10.
Melatonin receptors play important roles in the regulation of circadian and seasonal rhythms, sleep, retinal functions, the immune system, depression, and type 2 diabetes development. Melatonin receptors are approved drug targets for insomnia, non‐24‐hour sleep‐wake disorders, and major depressive disorders. In mammals, two melatonin receptors (MTRs) exist, MT1 and MT2, belonging to the G protein‐coupled receptor (GPCR) superfamily. Similar to most other GPCRs, reliable antibodies recognizing melatonin receptors proved to be difficult to obtain. Here, we describe the development of the first monoclonal antibodies (mABs) for mouse MT1 and MT2. Purified antibodies were extensively characterized for specific reactivity with mouse, rat, and human MT1 and MT2 by Western blot, immunoprecipitation, immunofluorescence, and proximity ligation assay. Several mABs were specific for either mouse MT1 or MT2. None of the mABs cross‐reacted with rat MTRs, and some were able to react with human MTRs. The specificity of the selected mABs was validated by immunofluorescence microscopy in three established locations (retina, suprachiasmatic nuclei, pituitary gland) for MTR expression in mice using MTR‐KO mice as control. MT2 expression was not detected in mouse insulinoma MIN6 cells or pancreatic beta‐cells. Collectively, we report the first monoclonal antibodies recognizing recombinant and native mouse melatonin receptors that will be valuable tools for future studies.  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-23

京公网安备 11010802026262号