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   309730篇
  免费   26712篇
  国内免费   18669篇
耳鼻咽喉   2648篇
儿科学   3865篇
妇产科学   5915篇
基础医学   36431篇
口腔科学   5605篇
临床医学   39534篇
内科学   49918篇
皮肤病学   3492篇
神经病学   17103篇
特种医学   10929篇
外国民族医学   123篇
外科学   33134篇
综合类   45407篇
现状与发展   58篇
一般理论   56篇
预防医学   19893篇
眼科学   8436篇
药学   31510篇
  240篇
中国医学   14749篇
肿瘤学   26065篇
  2024年   981篇
  2023年   4515篇
  2022年   11185篇
  2021年   14616篇
  2020年   10827篇
  2019年   9633篇
  2018年   10237篇
  2017年   9034篇
  2016年   8601篇
  2015年   13013篇
  2014年   16248篇
  2013年   15295篇
  2012年   22590篇
  2011年   24606篇
  2010年   15247篇
  2009年   12196篇
  2008年   16509篇
  2007年   16458篇
  2006年   15695篇
  2005年   15694篇
  2004年   10993篇
  2003年   9793篇
  2002年   8542篇
  2001年   7589篇
  2000年   7799篇
  1999年   8154篇
  1998年   4803篇
  1997年   4784篇
  1996年   3660篇
  1995年   3425篇
  1994年   2923篇
  1993年   1941篇
  1992年   2802篇
  1991年   2452篇
  1990年   2052篇
  1989年   1801篇
  1988年   1540篇
  1987年   1438篇
  1986年   1154篇
  1985年   916篇
  1984年   601篇
  1983年   459篇
  1982年   283篇
  1981年   242篇
  1980年   220篇
  1979年   283篇
  1978年   157篇
  1977年   126篇
  1974年   133篇
  1973年   112篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.

Purpose  

Hepatitis B virus (HBV) is endemic in Bangladesh, and the quality of life (QoL) of these patients remains unknown as there is no instrument available in the native language. In this study, we translated the 56-item Hepatitis Quality of Life Questionnaire (HQLQ) into Bengali and evaluated its validity and reliability.  相似文献   
102.
体育游戏是小学体育教学的重要内容,是教育学生最好的方法之一。我国现代著名教育家陈鹤琴先生说过:"小孩生来是好动的,是以游戏为生命的。"毛泽东同志在给《新体育》一书的题词中写道:"要活动,要游戏,是儿童的天性。"这充分说明了学生对游戏有着特殊的感情。  相似文献   
103.
104.
105.
106.
Background: Malposition of percutaneously inserted chest tubes is considered as a rare complication in critically ill patients. Its incidence, however, remains uncertain. The aims of the study were to assess the true incidence of chest tube malposition in critically ill patients and to identify predicting factors.

Methods: The authors prospectively studied 122 chest tubes percutaneously inserted in 75 consecutive critically ill patients. For clinical reasons independent of the study, thoracic computed tomography scanning was performed in 63 patients, allowing direct visualization of 106 chest tubes. Based on these findings, chest tube position was classified as intrapleural, intrafissural, or intraparenchymal. Factors predicting chest tube malposition were analyzed by univariate and multivariate analysis.

Results: The mean delay between chest tube placement and thoracic scan was 3.5 +/- 2.9 days. Twenty-two chest tubes were diagnosed as being intrafissural (21%), and 10 were diagnosed as being intraparenchymal (9%). The only predicting factor associated with the risk of malposition was the use of a trocar for the percutaneous insertion of the chest tube (P = 0.032).  相似文献   

107.
The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing cell death and tissue damage has been known for over forty years since the invention of lasers. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial in mainstream medicine. The biochemical mechanisms underlying the positive effects are incompletely understood, and the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength, fluence, power density, pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones. A biphasic dose response has been frequently observed where low levels of light have a much better effect on stimulating and repairing tissues than higher levels of light. The so-called Arndt-Schulz curve is frequently used to describe this biphasic dose response. This review will cover the molecular and cellular mechanisms in LLLT, and describe some of our recent results in vitro and in vivo that provide scientific explanations for this biphasic dose response.  相似文献   
108.
Purpose Post operative monitoring is crucial for the success of microsurgical free tissue transfer. Sophisticated and expensive methods are available for monitoring. We propose a novel technique using digital photography and the internet as a reliable and cost effective method to monitor free tissue transfers. Methods 163 micro‐vascular procedures were monitored using this technique over 8 months. Serial photographs taken to show flap color. Capillary refill time, pin prick‐ bleed time and color and hand held Doppler signal was recorded in the movie mode of a standard 5 mega pixel camera with duration of 15 seconds. Data was sent to the surgeon at regular intervals and or as deemed necessary. Results Analysis of the 67 cases is presented. 5 re‐explorations were done. The early diagnosis of venous congestion was possible using this technique. Timely intervention contributed to the success of the re‐explorations and these flaps could be salvaged. The file size of images was in the range of 1 MB–6 MB. The file size of an entire set of images ranged about 7 MB–9 MB. These were sent across the ADSL internet lines. Conclusion The use of the digital images and the internet allow reconstructive surgeons to have a reliable picture of the state of their free tissue transfers. This permits decrease in observer error and saves valuable time which otherwise needs to be spent to verify situations of doubt and offers an ideal solution to the logistic problem of having to visit the patient in case of doubt.  相似文献   
109.
110.
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