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   26159篇
  免费   2577篇
  国内免费   32篇
耳鼻咽喉   227篇
儿科学   1004篇
妇产科学   835篇
基础医学   3579篇
口腔科学   572篇
临床医学   3218篇
内科学   5063篇
皮肤病学   276篇
神经病学   2103篇
特种医学   673篇
外国民族医学   3篇
外科学   3356篇
综合类   658篇
一般理论   56篇
预防医学   3441篇
眼科学   383篇
药学   1867篇
中国医学   31篇
肿瘤学   1423篇
  2023年   167篇
  2022年   234篇
  2021年   587篇
  2020年   352篇
  2019年   557篇
  2018年   566篇
  2017年   455篇
  2016年   423篇
  2015年   468篇
  2014年   705篇
  2013年   1019篇
  2012年   1429篇
  2011年   1527篇
  2010年   744篇
  2009年   722篇
  2008年   1181篇
  2007年   1265篇
  2006年   1193篇
  2005年   1232篇
  2004年   1083篇
  2003年   1019篇
  2002年   916篇
  2001年   702篇
  2000年   745篇
  1999年   629篇
  1998年   299篇
  1997年   243篇
  1996年   243篇
  1995年   232篇
  1994年   179篇
  1993年   175篇
  1992年   499篇
  1991年   528篇
  1990年   496篇
  1989年   467篇
  1988年   393篇
  1987年   431篇
  1986年   402篇
  1985年   376篇
  1984年   315篇
  1983年   270篇
  1982年   173篇
  1981年   162篇
  1979年   233篇
  1978年   175篇
  1977年   191篇
  1974年   209篇
  1973年   188篇
  1972年   168篇
  1970年   167篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
In both adults and children with diabetes, technologies such as continuous subcutaneous insulin infusion using insulin pumps and continuous glucose monitoring can help improve diabetes control, reduce hypoglycaemia and improve quality of life. Access to these technologies in the UK is very variable. Some technologies are recommended by the National Institute for Health and Care Excellence, while others have not been appraised, and new technologies are emerging all the time. Additionally, different guidelines for adults and children further complicate access to diabetes technology in the transition from paediatric to adult care. Against this background, Diabetes UK and NHS England have brought together a multidisciplinary group of experts, including clinicians and people with diabetes, to develop this consensus guideline, combining the different technologies into a common pathway to aid clinical and policy decision‐making. We created a pathway that supports the incremental addition of technology as monotherapy and then dual therapy in the same way that we incrementally add in therapeutic agents to support people with Type 2 diabetes to achieve their personalized glycaemic targets. The pathway emphasizes the importance of structured education, specialist support and appropriate access to psychological therapies, as essential pillars for optimized use of diabetes‐related technology, and recommends the re‐evaluation of its use when the individual is unable either to use the technology appropriately or to achieve the intended outcomes. This pathway is endorsed by UK‐wide clinical and patient associations and we recommend that providers and commissioners use it to ensure the right individual with diabetes has access to the right technology in a timely way to help achieve better outcomes.  相似文献   
5.
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   
6.
7.
8.
To evaluate morbidity associated with surgical lengthening of the gastrocnemius, medical records were reviewed retrospectively for 126 patients (mean age, 49.7 years; range, 8-78 years) who had undergone open gastrocnemius recession. Ten patients had isolated recession; 116 had gastrocnemius recession with an additional foot or ankle procedure on the ipsilateral limb. During a mean follow-up period of 19 months (range, 6-50 months), all patients were examined for any postoperative complications associated with the recession. Complications were defined as the presence of postoperative infection, wound dehiscence, nerve problems, decreased muscle strength, scar problems, or calcaneus gait (overlengthening). Uncomplicated outcome was defined as absence of all these complications and return to regular activity, both occurring during a follow-up of at least 6 months. Postsurgical complications developed in 9 (6%) of the 126 patients: 6 (4%) had scar problems, 2 (1.33%) had wound dehiscence, 2 (1.33%) had infection, 3 (2%) had nerve problems, and 1 (0.67%) developed complex regional pain syndrome. No patient complained of either a limp or gait disturbance. Neither persistent decrease in muscle strength nor calcaneus gait was seen. These data suggest that the open gastrocnemius recession procedure has low associated morbidity.  相似文献   
9.
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   
10.
Background: Previous studies have shown that propofol and sevoflurane enhance the function of [gamma]-aminobutyric acid type A (GABAA) receptors. However, it is not known whether these two drugs modulate the same molecular pathways. In addition, little is known about receptor function in the presence of both propofol and sevoflurane. The aim of this study was to better understand the interactions of propofol and sevoflurane with the GABAA receptor.

Methods: Wild-type [alpha]1, [beta]2, [gamma]2s GABAA receptor subunit complementary DNAs were transfected into human embryonic kidney cells grown on glass coverslips using a calcium phosphate transfection method. After transfection (36-72 h), cells were whole cell patch clamped and exposed to combinations of the following: 0.3-1,000 [mu]m [gamma]-aminobutyric acid (GABA), 0-10 [mu]m propofol, and 0-1,650 [mu]m sevoflurane. Chemicals were delivered to the cells using two 10-channel infusion pumps and a rapid solution exchanger.

Results: Both propofol and sevoflurane alone enhanced the amplitude of GABAA receptor responses to submaximal concentrations of GABA in a dose-dependent manner. The enhancement was underpinned by an increase in the apparent affinity of the receptor for GABA. Coapplication of both anesthetics further enhanced the apparent affinity of the receptor for GABA.  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