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   176491篇
  免费   999篇
  国内免费   21篇
耳鼻咽喉   1129篇
儿科学   6639篇
妇产科学   2999篇
基础医学   16605篇
口腔科学   1598篇
临床医学   12381篇
内科学   31424篇
皮肤病学   663篇
神经病学   16470篇
特种医学   9001篇
外科学   28892篇
综合类   2309篇
预防医学   18050篇
眼科学   2732篇
药学   9522篇
中国医学   625篇
肿瘤学   16472篇
  2022年   30篇
  2021年   69篇
  2020年   39篇
  2019年   54篇
  2018年   21955篇
  2017年   17387篇
  2016年   19525篇
  2015年   925篇
  2014年   830篇
  2013年   800篇
  2012年   7037篇
  2011年   21052篇
  2010年   18828篇
  2009年   11522篇
  2008年   19524篇
  2007年   21743篇
  2006年   581篇
  2005年   2206篇
  2004年   3413篇
  2003年   4358篇
  2002年   2535篇
  2001年   288篇
  2000年   426篇
  1999年   178篇
  1998年   230篇
  1997年   210篇
  1996年   105篇
  1995年   120篇
  1994年   123篇
  1993年   83篇
  1992年   68篇
  1991年   98篇
  1990年   139篇
  1989年   95篇
  1988年   67篇
  1987年   56篇
  1986年   37篇
  1985年   45篇
  1984年   43篇
  1983年   33篇
  1982年   35篇
  1980年   53篇
  1974年   23篇
  1970年   28篇
  1969年   27篇
  1938年   60篇
  1937年   25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 15 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.
We describe our methods and outcomes of multidisciplinary treatments in patients with unresectable hilar cholangiocarcinoma. Fifty‐seven patients with a known outcome were enrolled. Thirty‐four of 57 patients were treated and evaluated by salvage therapy. For salvage therapy, we used internal and external radiotherapy, photodynamic therapy, YAG laser therapy and microwave coagulation therapy. The median survival time was 548 days for the group receiving salvage therapy and 198 days for the group not receiving this treatment. In conclusion, although no randomization of the patients was performed in this retrospective study, our present data provide convincing evidence that salvage therapy is a useful therapeutic approach for unresectable hilar cholangiocarcinomas.  相似文献   
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