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   32831篇
  免费   2904篇
  国内免费   37篇
耳鼻咽喉   241篇
儿科学   1110篇
妇产科学   1021篇
基础医学   4413篇
口腔科学   434篇
临床医学   4237篇
内科学   6409篇
皮肤病学   364篇
神经病学   2743篇
特种医学   821篇
外科学   3902篇
综合类   727篇
一般理论   59篇
预防医学   4284篇
眼科学   470篇
药学   2323篇
中国医学   30篇
肿瘤学   2184篇
  2023年   191篇
  2022年   261篇
  2021年   641篇
  2020年   414篇
  2019年   668篇
  2018年   723篇
  2017年   567篇
  2016年   568篇
  2015年   658篇
  2014年   903篇
  2013年   1385篇
  2012年   2004篇
  2011年   2084篇
  2010年   1089篇
  2009年   1027篇
  2008年   1681篇
  2007年   1887篇
  2006年   1753篇
  2005年   1804篇
  2004年   1599篇
  2003年   1560篇
  2002年   1398篇
  2001年   694篇
  2000年   691篇
  1999年   653篇
  1998年   391篇
  1997年   316篇
  1996年   314篇
  1995年   303篇
  1994年   245篇
  1993年   229篇
  1992年   479篇
  1991年   512篇
  1990年   481篇
  1989年   435篇
  1988年   387篇
  1987年   414篇
  1986年   378篇
  1985年   359篇
  1984年   323篇
  1983年   267篇
  1982年   190篇
  1981年   182篇
  1980年   138篇
  1979年   208篇
  1978年   162篇
  1977年   158篇
  1976年   140篇
  1974年   191篇
  1973年   168篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
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   
4.
5.
6.
7.
8.
Gender inequality is at the core of the HIV patterns that are evident in sub-Saharan Africa. Gender-based violence (GBV) and lack of economic opportunity are important structural determinants of HIV risk. We piloted a microfinance and health promotion intervention among social networks of primarily young men in Dar es Salaam. Twenty-two individuals participated in the microfinance component and 30 peer leaders were recruited and trained in the peer health leadership component. We collected and analysed observational data from trainings, monitoring data on loan repayment, and reports of peer conversations to assess the feasibility and acceptability of the intervention. Eighteen of the loan recipients (82%) paid back their loans, and of these 15 (83%) received a second, larger loan. Among the loan defaulters, one died, one had chronic health problems, and two disappeared, one of whom was imprisoned for theft. The majority of conversations reported by peer health leaders focused on condoms, sexual partner selection, and HIV testing. Few peer leaders reported conversations about GBV. We demonstrated the feasibility and acceptability of this innovative HIV and GBV prevention intervention. The lessons learned from this pilot have informed the implementation of a cluster-randomised trial of the microfinance and peer health leadership intervention.  相似文献   
9.
10.
The severity of illness in transplant patients and the complexity of transplant operations results in significant postoperative morbidity and mortality. Remarkable efforts have been made by transplant physicians to study and improve organ allocation, graft and patient survival, immunosuppression and the long-term management of post-transplant complications. Less effort has been spent studying the actual transplant operation and systems of acute transplant care. The National Surgical Quality Improvement Program (NSQIP) has provided a standardized approach to quality improvement and has demonstrated significant potential for a reduction in postoperative morbidity and mortality in other surgical disciplines. Medical centers are under increasing pressure to measure surgical quality and the nexus of transplant surgical quality improvement should not lie in the hands of CMS or JACHO, but rather it should be created and developed within the transplant community. The time has come for a national transplant surgical quality improvement program based on the NSQIP infrastructure. Such a proactive approach toward quality improvement from the transplant community is an excellent investment for patients, providers and health care payers.  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