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   2342261篇
  免费   175192篇
  国内免费   3289篇
耳鼻咽喉   32170篇
儿科学   75881篇
妇产科学   62722篇
基础医学   347889篇
口腔科学   63742篇
临床医学   210683篇
内科学   454999篇
皮肤病学   51737篇
神经病学   185247篇
特种医学   88065篇
外国民族医学   489篇
外科学   353818篇
综合类   47405篇
现状与发展   12篇
一般理论   848篇
预防医学   182074篇
眼科学   54254篇
药学   175051篇
  9篇
中国医学   4580篇
肿瘤学   129067篇
  2021年   18958篇
  2019年   19618篇
  2018年   27131篇
  2017年   20425篇
  2016年   22798篇
  2015年   25696篇
  2014年   36163篇
  2013年   54074篇
  2012年   74851篇
  2011年   79577篇
  2010年   47149篇
  2009年   44654篇
  2008年   74759篇
  2007年   79613篇
  2006年   80425篇
  2005年   77921篇
  2004年   74518篇
  2003年   71802篇
  2002年   69482篇
  2001年   108853篇
  2000年   111547篇
  1999年   93574篇
  1998年   27027篇
  1997年   23681篇
  1996年   24078篇
  1995年   22749篇
  1994年   20917篇
  1993年   19617篇
  1992年   71917篇
  1991年   70112篇
  1990年   68428篇
  1989年   65703篇
  1988年   60293篇
  1987年   59132篇
  1986年   55230篇
  1985年   53011篇
  1984年   39271篇
  1983年   33332篇
  1982年   19788篇
  1979年   35816篇
  1978年   25601篇
  1977年   21148篇
  1976年   20271篇
  1975年   21779篇
  1974年   26119篇
  1973年   24787篇
  1972年   23204篇
  1971年   22032篇
  1970年   20247篇
  1969年   19310篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
991.
Pulmonary infection complicating intra-abdominal sepsis is a major clinical problem. An experimental model for intra-abdominal sepsis was created with implantation of gelatin capsules, containing 3 x 10(8) cfu E. coli strain no. 2554, in the peritoneal cavity of 20 rats (10 animals received and 10 did not receive antibiotic therapy with ceftriaxone) in order to verify the role of the primary site of infection in the pathogenesis of pneumonia. Ten rats were sacrificed to determine the relative pulmonary weight and 10 were submitted to simple laparotomy and insertion of a germ-free capsule (sham-operated group). In this group of animals there was only one death (10%). All the rats that received antibiotic therapy survived until sacrifice while all the rats that did not receive ceftriaxone died, 7 within the 2nd and 3 on the 6th postoperative day. Pneumonia and peritonitis developed only in the animals that did not receive ceftriaxone. Bacteriological findings of material obtained from peritoneal and pleural cavities revealed the same strain of E. coli used for the experiment, suggesting that bacteria involved in the pleuro-pulmonary infections may originate in the primary site of infection and that antibiotic therapy started at the moment of contamination, can prevent this major complication.  相似文献   
992.
993.
994.
995.
996.
LUMBOVERTEBRAL SYNDROME AFTER EXTRADURAL BLOOD PATCH   总被引:2,自引:1,他引:1  
We describe a patient who developed an immobilizing lumbovertebralsyndrome after an extradural blood patch and who was hospitalizedwith a. suspected extradural abscess. An infectious aetiologyof the persistent backache could be excluded and the patientrecovered with analgesics and physiotherapy. The probable aetiologyis discussed.  相似文献   
997.
998.
Abstract: Establishment of mixed bone marrow chimerism in pig-to-primate transplantation, as a means of inducing specific immune tolerance, will require that both immune and nonimmune barriers be overcome. As a preliminary step in evaluating nonimmune barriers in this system, we have developed an in vitro model of engraftment in which long-term culture of porcine bone marrow-derived hematopoietic cells is supported on preformed primate bone marrow stromal layers. In the absence of cytokine supplementation, primate stromal cells were unable to support long-term porcine hematopoiesis in these cultures. Supplementation with porcine Steel Factor was required for long-term maintenance of hematopoietic progenitor cell content and total hematopoietic activity. Addition of porcine IL-3, in combination with porcine Steel Factor, increased long-term progenitor cell content and hematopoietic activity on primate stroma to levels comparable to that obtained in cultures on porcine stroma. The combination of porcine GM-CSF and Steel Factor increased progenitor cell content and hematopoietic activity early in the cultures, but had little effect in long-term cultures. The Steel Factor and IL-3 combination was species-specific in its action in these cultures, as the corresponding human cytokines were unable to effectively support long-term porcine hematopoiesis. Likewise, the combination of porcine cytokines had only minimal effects on long-term bone marrow culture of primate CD34+ cells I on primate stroma.  相似文献   
999.
To date, only 10 cases of distal penile gangrene in patients with chronic renal failure have been reported. This rare condition is believed to result from progressive vascular calcification due to secondary hyperparathyroidism in patients with chronic renal failure. We report an additional case of distal penile gangrene in a 41-year-old man who presented with chronic renal disease and pulmonary tuberculosis. Since some authors have emphasized that aggressive surgical treatment in such cases has a significant mortality rate, we took a more conservative approach to treatment.  相似文献   
1000.
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