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   257909篇
  免费   12423篇
  国内免费   531篇
耳鼻咽喉   3306篇
儿科学   7851篇
妇产科学   5258篇
基础医学   37164篇
口腔科学   6663篇
临床医学   20590篇
内科学   57108篇
皮肤病学   6852篇
神经病学   22919篇
特种医学   7602篇
外国民族医学   101篇
外科学   31280篇
综合类   1031篇
一般理论   70篇
预防医学   23514篇
眼科学   5030篇
药学   18043篇
中国医学   818篇
肿瘤学   15663篇
  2023年   1485篇
  2022年   1528篇
  2021年   4516篇
  2020年   2711篇
  2019年   4693篇
  2018年   8275篇
  2017年   5479篇
  2016年   5624篇
  2015年   6288篇
  2014年   6795篇
  2013年   10629篇
  2012年   18044篇
  2011年   18118篇
  2010年   9117篇
  2009年   6926篇
  2008年   15306篇
  2007年   16247篇
  2006年   14912篇
  2005年   14677篇
  2004年   13695篇
  2003年   12414篇
  2002年   11669篇
  2001年   6257篇
  2000年   6303篇
  1999年   5634篇
  1998年   1022篇
  1997年   849篇
  1996年   793篇
  1995年   700篇
  1992年   3256篇
  1991年   2926篇
  1990年   2770篇
  1989年   2534篇
  1988年   2406篇
  1987年   2214篇
  1986年   2116篇
  1985年   1918篇
  1984年   1432篇
  1983年   1211篇
  1979年   1220篇
  1978年   857篇
  1977年   806篇
  1975年   805篇
  1974年   991篇
  1973年   1001篇
  1972年   936篇
  1971年   924篇
  1970年   866篇
  1969年   910篇
  1968年   790篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Background Chromium allergy has traditionally been caused by occupational skin contact with cement. In 1983, Danish legislation made the addition of ferrous sulphate compulsory in cement to reduce the water‐soluble chromium content to not more than 2 ppm. An effect from this intervention has previously been demonstrated among Danish construction workers. Objectives To investigate the development of chromium allergy among patients with dermatitis tested between 1985 and 2007 in Denmark. Furthermore, to determine causative exposures in patients with chromium allergy. Patients and methods A retrospective analysis of patch test data was performed (n = 16 228) and charts from patients with chromium allergy were reviewed. Comparisons were made using a χ2 test. Logistic regression analyses were used to test for associations. Results The prevalence of chromium allergy decreased significantly from 3·6% in 1985 to 1% in 1995 (Ptrend < 0·001) but increased to 3·3% in 2007 (Ptrend < 0·001). The frequency of clinically relevant cement exposure decreased significantly among patients with chromium allergy from 12·7% in 1989–1994 to 3·0% (P < 0·01) in 1995–2007, whereas the frequency of relevant leather exposure increased significantly from 24·1% during 1989–1994 to 45·5% during 1995–2007 (P < 0·02). Conclusions Chromium allergy is currently increasing in Denmark due to leather exposure.  相似文献   
72.
Pain control is one of the most challenging aspects in the management of chronic pancreatitis. Total pancreatectomy can successfully relieve the intractable abdominal pain in these patients but will inevitably result in insulin-dependent diabetes. Islet autotransplantation aims to preserve, as far as possible, the insulin secretory function of the islet cell mass thereby reducing (or even removing) the requirement for exogenous insulin administration after a total pancreactomy. Despite the relatively small number of centres able to perform these procedures, there are important technical variations in the details of their approaches. The aim of this review is to provide details of the current surgical practice for total pancreatectomy combined with islet autotransplantation, and outline the potential advantages and disadvantages of the variations adopted in each centre.  相似文献   
73.
74.
75.
Protracted or recurrent pain and inflammation in the early neonatal period may cause long-lasting changes in central neural function. However, more research is necessary to better characterize the long-term behavioral sequelae of such exposure in the neonatal period. Objectives: (1) to study whether timing of postnatal exposure to persistent inflammation alters responsiveness to thermal pain in the adult animal; (2) to assess whether animals experiencing early postnatal chronic inflammation display altered anxiety related behavior; (3) to study the importance of genetic background. Newborn mice (outbred strain, CD1 and F1 hybrid strain, B6C3F1) received an injection of Complete Freund's Adjuvant (CFA) or saline on either postnatal day 1 or 14 (PND1; PND14) into the left hind paw. Pain to radiant heat and anxiety were examined in 12-week-old adult animals. Adult baseline PWL was significantly decreased in CD1 mice exposed to CFA on PND 1 and 14 as compared to their saline treated counterparts. B6C3F1 mice exposed to CFA on PND14 showed markedly reduced baseline PWL compared to the PND14 saline group. Persistent inflammation experienced by B6C3F1 mice on PND1 failed to affect baseline adult thermal responsiveness. Adult mice, CD1 and B6C3F1, displayed low anxiety traits only if they had been exposed to persistent inflammation on PND1 and not on PND14. Our research suggests a role for genetic background in modulating long-term behavioral consequences of neonatal persistent inflammation: the data support the hypothesis that pain experienced very early in life differentially affects adult behavioral and emotional responsiveness in outbred (CD1) and hybrid mice (B6C3F1).  相似文献   
76.
77.
78.
79.
80.
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