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   2348979篇
  免费   173105篇
  国内免费   3320篇
耳鼻咽喉   32050篇
儿科学   75906篇
妇产科学   62699篇
基础医学   348268篇
口腔科学   63636篇
临床医学   211407篇
内科学   457539篇
皮肤病学   51730篇
神经病学   185330篇
特种医学   88010篇
外国民族医学   489篇
外科学   353915篇
综合类   47509篇
现状与发展   12篇
一般理论   848篇
预防医学   182761篇
眼科学   54339篇
药学   175112篇
  11篇
中国医学   4575篇
肿瘤学   129258篇
  2021年   18996篇
  2019年   19550篇
  2018年   27082篇
  2017年   20363篇
  2016年   22757篇
  2015年   25655篇
  2014年   36124篇
  2013年   53980篇
  2012年   74711篇
  2011年   79453篇
  2010年   47077篇
  2009年   44586篇
  2008年   74647篇
  2007年   79518篇
  2006年   80328篇
  2005年   77814篇
  2004年   74402篇
  2003年   71721篇
  2002年   69391篇
  2001年   108755篇
  2000年   111465篇
  1999年   93506篇
  1998年   27003篇
  1997年   23662篇
  1996年   24059篇
  1995年   22720篇
  1994年   20896篇
  1993年   19717篇
  1992年   72010篇
  1991年   70073篇
  1990年   68398篇
  1989年   65673篇
  1988年   60304篇
  1987年   59137篇
  1986年   55227篇
  1985年   53015篇
  1984年   39321篇
  1983年   33401篇
  1982年   19863篇
  1979年   35868篇
  1978年   25654篇
  1977年   21230篇
  1976年   20333篇
  1975年   21817篇
  1974年   26149篇
  1973年   24802篇
  1972年   23201篇
  1971年   22038篇
  1970年   20247篇
  1969年   19316篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
The percentage uptake of [123I]metaiodobenzylguanidine (MIBG) by tumors of the paraganglion system is compared with the number of neurosecretory granules (assessed by both light and electron microscopy) in the subsequently resected tumors in six patients. Iodine-123 MIBG was injected intravenously; the tumor uptake of [123I]MIBG varied between 0.001% and 0.14% of the injected dose per gram of tumor tissue at 22 hr. The number of neurosecretory granules in tissue sections was scored on a scale of I-III. A direct proportional correlation was found between the percentage uptake of [123I]MIBG by the tumor and the number of neurosecretory granules in the tissue sections but not with plasma or urinary catecholamines. This technique for imaging reflects the storage status of the tumor better than plasma and urinary catecholamine measurements.  相似文献   
962.
Neuroblastoma: the role of MR imaging   总被引:1,自引:0,他引:1  
Thirty-five MR examinations were performed in 17 children with neuroblastoma during the course of their diagnostic evaluation and treatment. Findings were confirmed by correlation with the results of other imaging techniques, biopsies, and surgical and autopsy findings. MR accurately detected the lesions and their extent in all patients. It correctly evaluated the possibility of resectability and showed metastases, response to treatment and development of complications. MR appears to be a reliable technique for the diagnosis, staging, and follow-up of children with neuroblastoma.  相似文献   
963.
964.
965.
Ten knees with early tissue breakdown after knee arthroplasty resulting in exposed prostheses were treated with different plastic surgical techniques. Six knees were successfully covered: four using a gastrocnemius musculocutaneous flap, one using a fasciocutaneous flap, and one using split-skin grafts. Four knees failed: two using local skin flaps and two using split-skin grafts. A gastrocnemius musculocutaneous flap seems to provide a reliable coverage of the exposed knee joint.  相似文献   
966.
967.
968.
969.
Summary A group of thirty children with nasal fractures was evaluated retrospectively by means of a questionnaire and hospital records. Age at the time of injury ranged from age 3 to 12 (mean = 8.6) years and mean follow-up period was 9 years. Eight patients reported some degree of nasal obstruction post reduction, but only one patient required submucous resection and two patients underwent septorhinoplasty for appearance. No patients reported class III malocclusion, or required orthodontic treatment or maxillofacial corrective surgery for maxillary hypoplasia. We concluded that a childhood nasal fracture treated by closed reduction does not have deleterious effects on facial or nasal growth.This work was supported in part by the Brigham Surgical Group Foundation, Inc., Boston, Massachusetts, USA  相似文献   
970.
Summary A new modification of microvenous anastomosis, which has increased patency rates while simultaneously decreasing the difficulty of the procedure, is presented in this paper. The primary purpose of this study was to compare the classical and the temporary stent techniques of microvenous anastomosis. Because of problems such as mixing and tangling of strings during insertion and tying of the last four sutures while applying the temporary stent technique, we decided to modify the procedure. The silastic tube was removed through an incision (venotomy), distant from the actual suture line. This modified technique and the other above mentioned techniques were carried out on rat femoral veins. The results indicate that this modification has increased patency rates, shortened the time of anastomosis and facilitated the procedure.  相似文献   
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