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   1689688篇
  免费   126453篇
  国内免费   3771篇
耳鼻咽喉   21729篇
儿科学   55597篇
妇产科学   46159篇
基础医学   240977篇
口腔科学   48722篇
临床医学   150923篇
内科学   332557篇
皮肤病学   38650篇
神经病学   131020篇
特种医学   63850篇
外国民族医学   242篇
外科学   256931篇
综合类   38889篇
现状与发展   4篇
一般理论   531篇
预防医学   123896篇
眼科学   40098篇
药学   123517篇
  7篇
中国医学   4475篇
肿瘤学   101138篇
  2021年   12765篇
  2019年   13522篇
  2018年   19949篇
  2017年   15212篇
  2016年   16613篇
  2015年   18965篇
  2014年   26212篇
  2013年   37945篇
  2012年   52729篇
  2011年   55418篇
  2010年   32770篇
  2009年   30692篇
  2008年   51518篇
  2007年   54797篇
  2006年   55260篇
  2005年   52540篇
  2004年   50741篇
  2003年   48150篇
  2002年   46371篇
  2001年   91783篇
  2000年   93608篇
  1999年   76963篇
  1998年   19718篇
  1997年   17267篇
  1996年   17391篇
  1995年   16742篇
  1994年   15290篇
  1993年   14073篇
  1992年   57381篇
  1991年   55272篇
  1990年   52971篇
  1989年   50748篇
  1988年   46134篇
  1987年   44940篇
  1986年   42227篇
  1985年   39987篇
  1984年   29349篇
  1983年   24908篇
  1982年   13889篇
  1979年   25473篇
  1978年   17529篇
  1977年   14853篇
  1976年   13833篇
  1975年   14515篇
  1974年   17603篇
  1973年   16908篇
  1972年   15667篇
  1971年   14436篇
  1970年   13416篇
  1969年   12504篇
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
981.
Reported in this paper are postoperative results recorded from 120 patients, 3 years after selective proximal vagotomy for uncomplicated duodenal ulcer. There was no intraoperative lethality and no recurrence in 96.7 per cent of all cases, while Visick grades I on II were recorded from 98.2 per cent. Radiologically and gastroscopically detected pathological processes receded soon. Average postoperative reduction in acid secretion was 66.2 per cent in BAO and 46.8 per cent in MAO. Acid values re-increased thereafter, and three years later reduction rates still amounted to 43.7 per cent in BAO and 28.6 per cent in MAO. Indications for proximal gastric vagotomy are discussed in some detail.  相似文献   
982.
983.
Experience with the 'skew flap' below-knee amputation   总被引:3,自引:0,他引:3  
A review of 353 lower limb amputations over the last 7 years has been performed to assess the results of the skew flap myoplastic below-knee amputation which was introduced in April 1983 because of reported advantages in terms of wound healing and earlier ambulation. Comparing the first 3 1/2 year period with the second, the total number of amputations decreased by 31 per cent. The number of above-knee amputations remained similar in the two periods (82,62), whilst the number of Gritti-Stokes amputations fell from 79 to 21 (0.001 greater than P greater than 0.01). The proportion of below-knee (BK) amputations increased from 50 (23.7 per cent) to 59 (41.5 per cent) (0.01 greater than P greater than 0.025). The groups were comparable in terms of previous vascular surgery and co-existing medical conditions. The time to full stump healing was significantly shorter in the skew flap group compared with the earlier Burgess type BK amputation (P = 0.001), and there was a trend to fewer stump failures in the skew flap group. We therefore feel that the skew flap amputation gives superior results to the Burgess BK amputation in terms of healing and a lower complication rate, allowing a higher proportion of BK amputations to be performed. A prospective randomized trial of the two techniques is in hand to determine the accuracy of this hypothesis.  相似文献   
984.
Topical analgesia for relief of post-circumcision pain   总被引:1,自引:0,他引:1  
  相似文献   
985.
986.
Three evaluation instruments (global, check-list, and criterion referenced) were used by experienced and inexperienced examiners to evaluate dental sealant end products on 40 extracted teeth. Intra- and interexaminer reliabilities were measured. Experienced examiners achieved higher intrarater reliabilities with all three evaluation instruments than did inexperienced examiners. The highest intraexaminer agreement for all examiners occurred with use of the global evaluation. The highest interexaminer reliability was achieved with the second use of the criterion-referenced evaluation by the experienced examiner. Interexaminer reliability was improved for both types of examiners with the criterion-referenced evaluation.  相似文献   
987.
A 65-year-old man with spontaneous rupture of the esophagus survived with a direct suture of the esophagus 15 hours after the onset of symptoms. Endoscopic examination of the esophagus was especially of great help in determining the surgical procedure in this patient, and we want to stress the importance of prompt diagnosis and immediate surgery for this disease.  相似文献   
988.
989.
990.
Effects of dexamethasone on central and peripheral ACTH systems in the rat   总被引:1,自引:0,他引:1  
To investigate the simultaneous effects of dexamethasone on peripheral and central adrenocorticotropic hormone (ACTH) systems, rats were treated with dexamethasone or saline for 4 days. Pituitary, plasma, hypothalamus and cerebrospinal fluid (CSF) were then collected and analyzed for ACTH immunoreactivity. Additionally, hypothalamic tissue extracts were analyzed for corticotropin-releasing hormone (CRH) immunoreactivity. Dexamethasone significantly lowered peripheral levels of ACTH as measured in pituitary and plasma. Hypothalamic ACTH content significantly increased while CSF ACTH significantly decreased with dexamethasone treatment. Hypothalamic CRH concentrations showed a small but statistically insignificant decrease. These results suggest that prolonged exposure to dexamethasone affects central as well as peripheral ACTH activity, corroborate our previous findings in rhesus monkeys of decreased CSF ACTH in response to prolonged dexamethasone treatment, suggest that dexamethasone may inhibit the release of ACTH from hypothalamic neurons into the CSF, and provide evidence that the effect of dexamethasone on pituitary ACTH content is of greater magnitude than its effect on hypothalamic CRH.  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