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   174770篇
  免费   934篇
  国内免费   4篇
耳鼻咽喉   1128篇
儿科学   6612篇
妇产科学   2996篇
基础医学   16439篇
口腔科学   1528篇
临床医学   12279篇
内科学   30578篇
皮肤病学   666篇
神经病学   16353篇
特种医学   8882篇
外科学   28716篇
综合类   2328篇
一般理论   3篇
预防医学   18058篇
眼科学   2761篇
药学   9430篇
中国医学   626篇
肿瘤学   16325篇
  2021年   27篇
  2020年   27篇
  2019年   20篇
  2018年   21933篇
  2017年   17364篇
  2016年   19517篇
  2015年   890篇
  2014年   776篇
  2013年   752篇
  2012年   6911篇
  2011年   20941篇
  2010年   18775篇
  2009年   11477篇
  2008年   19435篇
  2007年   21642篇
  2006年   474篇
  2005年   2103篇
  2004年   3304篇
  2003年   4279篇
  2002年   2424篇
  2001年   264篇
  2000年   407篇
  1999年   159篇
  1998年   198篇
  1997年   198篇
  1996年   85篇
  1995年   99篇
  1994年   94篇
  1993年   58篇
  1992年   36篇
  1991年   83篇
  1990年   132篇
  1989年   78篇
  1988年   53篇
  1987年   44篇
  1986年   26篇
  1985年   31篇
  1984年   22篇
  1983年   21篇
  1982年   28篇
  1980年   43篇
  1974年   22篇
  1969年   20篇
  1939年   20篇
  1938年   61篇
  1937年   25篇
  1935年   22篇
  1934年   30篇
  1932年   56篇
  1930年   46篇
排序方式: 共有10000条查询结果,搜索用时 797 毫秒
11.
12.
Contraceptive use is an important strategy for the prevention of unwanted pregnancy and avoidance of induced abortion. Of all the contraception methods, emergency contraceptive (EC) offers the last chance to achieve this. However, few studies have documented the use of EC among young people in Ghana. This study explored knowledge and usage of EC as well as the factors associated with it among University of Cape Coast students. Data were obtained on the knowledge and usage of ECs among University of Cape Coast students in 2013. Logistic regression analysis was used to investigate the association between students’ socio-demographic characteristics and EC knowledge and use. More male students (72 %) than females (59 %) were sexually active. Fifty-seven percent of the respondents had ever heard of EC and 36 % had ever used EC. Although males were more likely to be sexually active, females were more likely to have knowledge of EC use compared to males. The study underscores the need to increase awareness regarding EC among University students in order to offer them the opportunity that EC provides if other forms of contraceptives are missed.  相似文献   
13.
14.
Gastroesophageal reflux is the most common benign disorder of the esophagus and laparoscopic Nissen fundoplication has become the standard surgical treatment for its treatment. In our area, where the use of bougie calibration is debatable, postoperative dysphagia is encountered often after this surgery although it is usually not permanent. The aim of this study was to investigate the effect of using a soft silicone tube 39 F in diameter for esophageal calibration during laparoscopic Nissen fundoplication on the incidence of postoperative dysphagia. We divided cases scheduled to undergo laparoscopic Nissen fundoplication between January 2009 and November 2010 into two groups, each consisting 25 patients. Esophageal calibration with a 39 F silicone orogastric tube was used for the first group while there was no operative calibration in the second group. The surgical duration was recorded; the presence and severity of the postoperative dysphagia was calculated by using a dysphagia severity scoring system during the 1-year postoperative follow-up. The dysphagia severity scores were significantly lower in group 1 than group 2 on the postoperative second day and at the end of the first week and first month. We did not find a significant difference at the end of the 6-month and first year. There was also no significant difference regarding surgery duration. The use of a soft orogastric tube 39 F in diameter for esophagus calibration during laparoscopic Nissen fundoplication has significantly decreased the incidence of postoperative transient dysphagia without affecting the duration of surgery. Although dysphagia gradually resolves in the majority of patients, a safe and easy calibration method for its prevention is worth developing, and we believe that the use of our method in larger series could be beneficial.  相似文献   
15.
16.
17.
18.
19.
20.
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