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   1922709篇
  免费   134447篇
  国内免费   3790篇
耳鼻咽喉   26300篇
儿科学   63816篇
妇产科学   53252篇
基础医学   275155篇
口腔科学   53807篇
临床医学   172653篇
内科学   366564篇
皮肤病学   44026篇
神经病学   148814篇
特种医学   75174篇
外国民族医学   497篇
外科学   290461篇
综合类   42313篇
现状与发展   1篇
一般理论   626篇
预防医学   142524篇
眼科学   44397篇
药学   146710篇
  9篇
中国医学   4359篇
肿瘤学   109488篇
  2018年   20054篇
  2017年   15637篇
  2016年   17858篇
  2015年   19991篇
  2014年   27344篇
  2013年   40840篇
  2012年   54984篇
  2011年   58390篇
  2010年   34690篇
  2009年   32531篇
  2008年   54345篇
  2007年   57954篇
  2006年   58916篇
  2005年   56364篇
  2004年   54493篇
  2003年   52313篇
  2002年   50493篇
  2001年   96768篇
  2000年   99310篇
  1999年   83019篇
  1998年   21959篇
  1997年   19455篇
  1996年   19466篇
  1995年   18493篇
  1994年   16997篇
  1993年   15997篇
  1992年   64366篇
  1991年   62307篇
  1990年   61500篇
  1989年   59281篇
  1988年   53661篇
  1987年   53100篇
  1986年   49749篇
  1985年   47460篇
  1984年   35026篇
  1983年   29547篇
  1982年   16947篇
  1981年   15049篇
  1979年   31780篇
  1978年   22100篇
  1977年   19351篇
  1976年   17515篇
  1975年   19071篇
  1974年   22606篇
  1973年   21878篇
  1972年   20508篇
  1971年   19173篇
  1970年   17680篇
  1969年   16844篇
  1968年   15303篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
101.
A 17-year-old man presented with signs of peritonitis. Laparotomy revealed gangrene of the stomach without obvious cause. The patient underwent total gastrectomy with esophago-jejunal anastomosis with formation of jejunal pouch. Bacterial culture of the peritoneal fluid grew Strept. pyogenes and E. coli. The patient was discharged on day 21 after a stormy postoperative course.  相似文献   
102.
103.
Carbon monoxide (CO), a byproduct of heme catalysis, was shown to have potent cytoprotective and anti-inflammatory effects. In vivo recipient CO inhalation at low concentrations prevented ischemia/reperfusion (I/R) injury associated with small intestinal transplantation (SITx). This study examined whether ex vivo delivery of CO in University of Wisconsin (UW) solution could ameliorate intestinal I/R injury. Orthotopic syngenic SITx was performed in Lewis rats after 6 h cold preservation in control UW or UW that was bubbled with CO gas (0.1-5%) (CO-UW). Recipient survival with intestinal grafts preserved in 5%, but not 0.1%, CO-UW improved to 86.7% (13/15) from 53% (9/17) with control UW. At 3 h after SITx, grafts stored in 5% CO-UW showed improved intestinal barrier function, less mucosal denudation and reduced inflammatory mediator upregulation compared to those in control UW. Preservation in CO-UW associated with reduced vascular resistance (end preservation), increased graft cyclic guanosine monophosphate levels (1 h), and improved graft blood flow (1 h). Protective effects of CO-UW were reversed by ODQ, an inhibitor of soluble guanylyl cyclase. In vitro culture experiment also showed better preservation of vascular endothelial cells with CO-UW. The study suggests that ex vivo CO delivery into UW solution would be a simple and innovative therapeutic strategy to prevent transplant-induced I/R injury.  相似文献   
104.
105.
The absence of the temporary incisors could be to a genetic illness or to some multiple premature extractions. These extractions are the aftermaths of the carious lesions or some traumatisms underwent by the temporary incisors. Beyond measure the loss of the space, the premature loss some temporary incisors very often assign the relational development of the child and disturb its psychological development and the aesthetic function. Across some cases clinics, the authors show that the replacement of the temporary incisors is the therapeutic ideal solution. Indeed, the child prosthesis, replacing the temporary absent incisors, solves the psychological, aesthetic and relational problems of the child.  相似文献   
106.
107.
108.
Summary The third-stage larvae of Daniconema anguillae Moravec et K?ie, 1987 are found in the eels fins caught from Dringis Lake (Lithuanian National park). The morphology of these larvae is briefly described.  相似文献   
109.
The results of lumbar fusion in chronic low back pain (LBP) patients vary considerably, and there is a need for proper patient selection. Lumbosacral orthoses have been widely used to predict outcome, however, with little scientific support. The aim of the present study was to determine the value of a pantaloon cast test in selecting chronic LBP patients for lumbar fusion or conservative management. First, a systematic review of the literature was carried out in which two independent reviewers identified studies in Medline, Cochrane and Current Contents databases. Three papers met the selection criteria. In the only study with a control group, a significantly better outcome after fusion compared to conservative treatment was found in patients who reported significant pain relief while in a cast (i.e. a positive cast test). The results of lumbar fusion, however, were not significantly different for patients with a positive and those with a negative cast test. In addition to the review, a clinical cohort study of 257 LBP patients, who had been allocated to either lumbar fusion or conservative management by a temporary external transpedicular fixation trial, was performed. Prior to allocation, all had undergone a pantaloon cast test. Patients with no history of prior spine surgery and with a positive pantaloon cast test had a better outcome after lumbar fusion than those treated conservatively (P = 0.002, χ 2 test). In patients with previous spine operations the outcomes were poor and the test was of no value. From the literature and the present patient cohort, it was concluded that only in chronic LBP patients without prior spine surgery, a pantaloon cast test with substantial pain relief suggests a favorable outcome of lumbar fusion compared to conservative management. The test has no value in patients who have had previous spine surgery.  相似文献   
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