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   1450457篇
  免费   118903篇
  国内免费   3423篇
耳鼻咽喉   18753篇
儿科学   48168篇
妇产科学   42192篇
基础医学   205838篇
口腔科学   38142篇
临床医学   131563篇
内科学   291697篇
皮肤病学   34220篇
神经病学   121054篇
特种医学   54646篇
外国民族医学   464篇
外科学   214878篇
综合类   33147篇
现状与发展   4篇
一般理论   570篇
预防医学   116112篇
眼科学   32219篇
药学   101464篇
  1篇
中国医学   3402篇
肿瘤学   84249篇
  2021年   12291篇
  2019年   13157篇
  2018年   18144篇
  2017年   13889篇
  2016年   15571篇
  2015年   17354篇
  2014年   24453篇
  2013年   35930篇
  2012年   49123篇
  2011年   51656篇
  2010年   30217篇
  2009年   28736篇
  2008年   47241篇
  2007年   49769篇
  2006年   50132篇
  2005年   48424篇
  2004年   45931篇
  2003年   43560篇
  2002年   41806篇
  2001年   73204篇
  2000年   74664篇
  1999年   61763篇
  1998年   17262篇
  1997年   15619篇
  1996年   15741篇
  1995年   14929篇
  1994年   13499篇
  1993年   12663篇
  1992年   45902篇
  1991年   43537篇
  1990年   41539篇
  1989年   39607篇
  1988年   36227篇
  1987年   35386篇
  1986年   32891篇
  1985年   31308篇
  1984年   23871篇
  1983年   20067篇
  1982年   12229篇
  1981年   10803篇
  1979年   20716篇
  1978年   14600篇
  1977年   12102篇
  1976年   11383篇
  1975年   11646篇
  1974年   14000篇
  1973年   13555篇
  1972年   12652篇
  1971年   11479篇
  1970年   10921篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Although general suggestions have been made regarding a radiology residency curriculum, no specific list of entities has been offered. Over the past ten years, we have developed a resident-run morning conference in musculoskeletal radiology that is supervised by faculty and covers a specific curriculum. We offer our curriculum as an example that may assist other departments in developing their own curricula.  相似文献   
992.
Lumbar subarachnoid catheterization in rats   总被引:3,自引:0,他引:3  
An animal model was developed for the study of subarachnoid (spinal) anesthesia and analgesia under unanesthetized, unsedated and unrestrained conditions. Sprague-Dawley rats were anesthetized with intraperitoneal ketamine (75-100 mg.kg-1). A PE10 catheter was inserted under direct vision into the lumbar subarachnoid space, through partial laminectomy of L1 or L2 with or without removal of adjacent intervertebral ligament. One week after surgery, correct position of the catheter was verified by subarachnoid injection of 0.03-0.05 ml of 1.5% lidocaine, which produced temporary hind limb paralysis in all but one animal in 28 consecutive operations. There was neither mortality nor major complication, intraoperatively or postoperatively. Only 2 animals developed minor subcutaneous would infections which responded to incision, drainage and debridement.  相似文献   
993.
Sixty drinking water samples collected from various sources in different areas of Delhi during epidemic of cholera and gastroenteritis were analysed for bacteriological standards. Only 27 (45 per cent) samples were found to be satisfactory for human consumption. Remaining thirty-three (55 per cent) samples showed presence of coliform organisms with MPN value ranging from 10 to 1800+ per 100 ml. Among these positive samples, 31 (93.9 per cent) samples contained faecal coli. Twenty out of thirty (66.6 per cent) Hand pump, 9 out of 21 (42.8 per cent) Taps 2 out of 4 (50 per cent) Tube well and 2 out of 5 (40 per cent) of miscellaneous sources showed contamination with coliform organisms.  相似文献   
994.
995.
996.
997.
998.
We carried out a nonrandomized, unblinded study to compare the efficacy of rifampin alone with that of rifampin in combination with trimethoprim in the eradication of the Haemophilus influenzae type b (HIB) carrier state among contacts of patients with invasive HIB infection. The study population comprised 17 index patients admitted to hospital with severe HIB infections and 233 contacts, 43 of whom had nasopharyngeal colonization with HIB of the same biotype as that of the index patient. Rifampin in a daily dose of 20 mg/kg (maximum 600 mg) for 4 days eradicated the carrier state in 86% of cases, as did the combination of rifampin at the same dosage and trimethoprim in a daily dose of 5 mg/kg (maximum 160 mg) for 4 days.  相似文献   
999.
1000.
Intravenous administration of human bone marrow stromal cells (hMSCs) after middle cerebral artery occlusion (MCAo) in rats provides functional benefit. We tested the hypothesis that these functional benefits are derived in part from hMSC production of growth and trophic factors. Quantitative sandwich enzyme‐linked immunosorbent assay (ELISA) of hMSCs cultured with normal and MCAo brain extracts were performed. hMSCs cultured in supernatant derived from ischemic brain extracts increased production of brain‐derived neurotrophic factor (BDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF). These neurotrophins and angiogenic growth factors increased in a post‐ischemia time‐dependent manner. The hMSC capacity to increase expression of growth and trophic factors may be the key to the benefit provided by transplanted hMSCs in the ischemic brain.  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