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   39143篇
  免费   2545篇
  国内免费   97篇
耳鼻咽喉   453篇
儿科学   1443篇
妇产科学   965篇
基础医学   4810篇
口腔科学   465篇
临床医学   6536篇
内科学   6751篇
皮肤病学   403篇
神经病学   3742篇
特种医学   804篇
外国民族医学   1篇
外科学   3603篇
综合类   367篇
一般理论   49篇
预防医学   5533篇
眼科学   408篇
药学   2424篇
中国医学   44篇
肿瘤学   2984篇
  2024年   30篇
  2023年   323篇
  2022年   450篇
  2021年   851篇
  2020年   606篇
  2019年   942篇
  2018年   1095篇
  2017年   814篇
  2016年   854篇
  2015年   954篇
  2014年   1337篇
  2013年   2101篇
  2012年   3046篇
  2011年   3239篇
  2010年   1722篇
  2009年   1553篇
  2008年   2804篇
  2007年   2809篇
  2006年   2743篇
  2005年   2693篇
  2004年   2486篇
  2003年   2209篇
  2002年   2122篇
  2001年   256篇
  2000年   230篇
  1999年   282篇
  1998年   441篇
  1997年   339篇
  1996年   263篇
  1995年   212篇
  1994年   218篇
  1993年   214篇
  1992年   139篇
  1991年   121篇
  1990年   106篇
  1989年   107篇
  1988年   91篇
  1987年   87篇
  1986年   95篇
  1985年   88篇
  1984年   101篇
  1983年   82篇
  1982年   92篇
  1981年   100篇
  1980年   71篇
  1979年   42篇
  1978年   31篇
  1977年   39篇
  1976年   22篇
  1975年   25篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
PurposeUnderstanding the value of genetic screening and testing for monogenic disorders requires high-quality, methodologically robust economic evaluations. This systematic review sought to assess the methodological quality among such studies and examined opportunities for improvement.MethodsWe searched PubMed, Cochrane, Embase, and Web of Science for economic evaluations of genetic screening/testing (2013-2019). Methodological rigor and adherence to best practices were systematically assessed using the British Medical Journal checklist.ResultsAcross the 47 identified studies, there were substantial variations in modeling approaches, reporting detail, and sophistication. Models ranged from simple decision trees to individual-level microsimulations that compared between 2 and >20 alternative interventions. Many studies failed to report sufficient detail to enable replication or did not justify modeling assumptions, especially for costing methods and utility values. Meta-analyses, systematic reviews, or calibration were rarely used to derive parameter estimates. Nearly all studies conducted some sensitivity analysis, and more sophisticated studies implemented probabilistic sensitivity/uncertainty analysis, threshold analysis, and value of information analysis.ConclusionWe describe a heterogeneous body of work and present recommendations and exemplar studies across the methodological domains of (1) perspective, scope, and parameter selection; (2) use of uncertainty/sensitivity analyses; and (3) reporting transparency for improvement in the economic evaluation of genetic screening/testing.  相似文献   
2.
3.
4.
5.
6.
7.
8.
9.
Obtaining accurate assessment data from adolescents in treatment aids clinical decision making and facilitates more accurate outcome evaluations. However, findings could be biased due to underreported substance use and mental health symptoms. This article compares self-reports of youth in non-White matched client–assessor dyads and those in nonmatched dyads. There were no differences on self-reported substance use, but matched youth reported significantly fewer attention deficit/hyperactivity disorder symptoms versus the comparison group. One possible reason for these findings is the effect of in-group stereotype threat. Future studies should examine the potential effect that in-group stereotyping and perceived racism have on the therapeutic relationship.  相似文献   
10.
Recent work suggests that while voluntary episodic memory declines with age, involuntary episodic memory, which comes to mind spontaneously without intention, remains relatively intact. However, the neurophysiology underlying these differences has yet to be established. The current study used electroencephalography (EEG) to investigate voluntary and involuntary retrieval in older and younger adults. Participants first encoded sounds, half of which were paired with pictures, the other half unpaired. EEG was then recorded as they listened to the sounds, with participants in the involuntary group performing a sound localization cover task, and those in the voluntary group additionally attempting to recall the associated pictures. Participants later reported which sounds brought the paired picture to mind during the localization task. Reaction times on the localization task were slower for voluntary than involuntary retrieval and for paired than unpaired sounds, possibly reflecting increased attentional demands of voluntary retrieval and interference from reactivation of the associated pictures respectively. For the EEG analyses, young adults showed greater alpha event-related desynchronization (ERD) during voluntary than involuntary retrieval at frontal and occipital sites, while older adults showed pronounced alpha ERD regardless of intention. Additionally, older adults showed greater ERD for paired than unpaired sounds at occipital sites, likely reflecting visual reactivation of the associated pictures. Young adults did not show this alpha ERD memory effect. Taken together, these data suggest that involuntary memory is largely preserved with age, but this may be due to older adults' greater recruitment of top-down control even when demand for such control is limited.  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