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   3516007篇
  免费   271428篇
  国内免费   6869篇
耳鼻咽喉   49733篇
儿科学   112114篇
妇产科学   94658篇
基础医学   495683篇
口腔科学   103113篇
临床医学   320706篇
内科学   681202篇
皮肤病学   74893篇
神经病学   286185篇
特种医学   136550篇
外国民族医学   1084篇
外科学   531050篇
综合类   83991篇
现状与发展   5篇
一般理论   1394篇
预防医学   278430篇
眼科学   84216篇
药学   262364篇
  11篇
中国医学   7484篇
肿瘤学   189438篇
  2018年   37568篇
  2017年   28714篇
  2016年   31765篇
  2015年   35995篇
  2014年   51157篇
  2013年   76919篇
  2012年   104751篇
  2011年   110733篇
  2010年   65581篇
  2009年   61939篇
  2008年   104119篇
  2007年   110911篇
  2006年   111864篇
  2005年   108518篇
  2004年   104542篇
  2003年   100304篇
  2002年   98094篇
  2001年   166754篇
  2000年   172007篇
  1999年   144795篇
  1998年   41123篇
  1997年   36679篇
  1996年   36343篇
  1995年   35161篇
  1994年   32822篇
  1993年   30424篇
  1992年   114834篇
  1991年   111169篇
  1990年   107272篇
  1989年   103617篇
  1988年   95684篇
  1987年   93982篇
  1986年   88846篇
  1985年   84752篇
  1984年   63812篇
  1983年   54376篇
  1982年   32215篇
  1981年   28770篇
  1979年   58790篇
  1978年   41064篇
  1977年   34890篇
  1976年   32650篇
  1975年   34467篇
  1974年   42421篇
  1973年   40474篇
  1972年   37889篇
  1971年   34987篇
  1970年   32871篇
  1969年   30587篇
  1968年   28086篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Summary: The mosaic (Atp7a mo-ms ) is an X-linked, lethal mutation in mice. In mosaic mutant males, many clinical features characteristic of defective copper metabolism have been observed and they die at the age of 15 days, exhibiting strongsimilarities to the brindled and macular mutants. About 4% of the mutant males live to sexual maturity and some of them are fertile. In this paper, alterationsin the structure of the kidney from adult mutants are described. Owing to an inherited defect of efflux, copper is accumulated in the kidney of the mutants up to a toxic level and this leads to severe damage of the renal cortex. Pathological changes in the kidney mostly affected the structure of the renal corpuscle and renaltubules.  相似文献   
992.
993.
994.
995.
OBJECTIVE: To determine whether under-reporting of rheumatic fever occurs at hospital, municipal, provincial and national levels of the South African health system. BACKGROUND: Information on the incidence of rheumatic fever (RF) and the prevalence of rheumatic heart disease (RHD) is required for the prevention of valvular heart disease in developing countries. In South Africa, RF was made a notifiable condition in 1989. It has recently been suggested that the reporting of RF cases may be incomplete, possibly because of underreporting by health care professionals and deficient administration of the disease notification system in South Africa. METHOD AND RESULTS: We assessed whether underreporting of RF cases occurs by comparing the numbers of RF cases reported per year at hospital, municipal, provincial and national levels from 1990 to 2004. There was a fall in the number of RF cases reported per year at national and provincial level over the 15 years of observation. A detailed analysis of the number of RF cases reported at hospital, municipal and provincial level for a 5-year period showed that more cases were diagnosed in one hospital (serving a smaller population) than were captured at municipal and provincial level (serving a larger population), suggesting underreporting by health care professionals. There were discrepancies in the number of cases reported at municipal, provincial and national level, suggesting poor administration of the notification system. CONCLUSION: There appears to be underreporting of RF cases by health care professionals, and poor administration of the RF notification system. Health care professionals need to be educated about the statutory requirement to notify all RF cases in South Africa. An effective national disease notification system is required.  相似文献   
996.
997.
998.
Objective. The safety and efficacy of intrathecal (IT) ziconotide was studied in a randomized, double‐blind, placebo‐controlled trial. Materials and Methods. Patients (169 ziconotide, 86 placebo) with severe chronic nonmalignant pain unresponsive to conventional therapy and a visual analog scale of pain intensity (VASPI score) ≥ 50 mm were treated over a 6‐day period in an inpatient hospital setting. Initial starting dose was 0.4 µg/hour and was titrated to analgesia or intolerance (maximum dose 7.0 µg/hour). The starting and maximum doses were reduced to 0.1 µg/hour and 2.4 µg/hour, respectively, due to adverse events (AEs). Results. The mean percent reduction in VASPI score from baseline was 31.2% and 6.0% for ziconotide‐ and placebo‐treated patients, respectively (p ≤ 0.001). During the initial titration phase, a significantly greater percentage of patients in the ziconotide group compared to the placebo group reported AEs, including abnormal gait, amblyopia, dizziness, nausea, nystagmus, pain, urinary retention, and vomiting. Conclusion. Ziconotide provided significant analgesia in patients for whom conventional therapy failed. However, there was a considerable incidence of ziconotide‐associated AEs due to the rapid titration and high doses administered.  相似文献   
999.
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