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   1427768篇
  免费   97769篇
  国内免费   2014篇
耳鼻咽喉   18669篇
儿科学   47325篇
妇产科学   39947篇
基础医学   210411篇
口腔科学   39666篇
临床医学   130299篇
内科学   276740篇
皮肤病学   31031篇
神经病学   111733篇
特种医学   56088篇
外国民族医学   356篇
外科学   203339篇
综合类   26757篇
现状与发展   3篇
一般理论   570篇
预防医学   118546篇
眼科学   31681篇
药学   103769篇
  8篇
中国医学   2158篇
肿瘤学   78455篇
  2018年   16765篇
  2017年   13990篇
  2016年   14214篇
  2015年   17551篇
  2014年   21905篇
  2013年   30524篇
  2012年   46573篇
  2011年   44141篇
  2010年   24986篇
  2009年   25709篇
  2008年   39501篇
  2007年   42798篇
  2006年   42636篇
  2005年   49217篇
  2004年   49123篇
  2003年   43427篇
  2002年   37871篇
  2001年   59281篇
  2000年   58379篇
  1999年   52553篇
  1998年   13824篇
  1997年   12433篇
  1996年   12905篇
  1995年   12197篇
  1994年   11385篇
  1992年   43390篇
  1991年   43102篇
  1990年   42055篇
  1989年   40615篇
  1988年   37741篇
  1987年   36927篇
  1986年   35193篇
  1985年   32870篇
  1984年   24794篇
  1983年   21469篇
  1982年   12170篇
  1979年   23988篇
  1978年   17272篇
  1977年   14207篇
  1976年   13116篇
  1975年   14819篇
  1974年   18168篇
  1973年   17618篇
  1972年   16795篇
  1971年   15840篇
  1970年   14910篇
  1969年   14138篇
  1968年   13128篇
  1967年   11896篇
  1966年   11200篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.

Aims

Variations of the anatomy of donor hepatic arteries increase the number of arterial anastomoses during liver transplantation and, possibly, the incidence of hepatic artery thrombosis (HAT). In this study, we describe the arterial anatomic variations in liver grafts procured and transplanted by a single center in Greece, the techniques of arterial anastomosis, and their effect on the incidence of early HAT.

Materials and Methods

From January 2013 to December 2017, the arterial anatomy of 116 grafts procured for liver transplantation were recorded, as well as the technique of arterial anastomosis and the incidence of early hepatic artery thrombosis (HAT <30 days).

Results

A single hepatic artery was recorded in 72.41% of the procured grafts, an aberrant left hepatic artery (accessory or replaced) in 18 grafts (15.52%), and an aberrant right hepatic artery (accessory or replaced) in 17 grafts (14.66%), while other variations were observed in less than 1% of the procured livers. Of the 116 primary liver transplantations, 6 patients (5.17%) developed early HAT <30 days. Two of these patients (1.72%) had 1 anastomosis of the hepatic artery and 4 (3.45%) had 2 anastomoses due to anatomic variations.

Conclusions

Anatomic variations of the hepatic artery in liver grafts is a common finding and increase the incidence of early HAT but not to a degree to make these grafts unusable.  相似文献   
93.
Several regulatory bodies have agreed that low-dose radiation used in medical imaging is a weak carcinogen that follows a linear, non-threshold model of cancer risk. While avoiding radiation is the best course of action to mitigate risk, computed tomography (CT) scans are often critical for diagnosis. In addition to the as low as reasonably achievable principle, a more concrete method of dose reduction for common CT imaging exams is the use of a diagnostic reference level (DRL). This paper examines Canada's national DRL values from the recent CT survey and compares it to published provincial DRLs as well as the DRLs in the United Kingdom and the United States of America for the 3 most common CT exams: head, chest, and abdomen/pelvis. Canada compares well on the international scale, but it should consider using more electronic dose monitoring solutions to create a culture of dose optimization.  相似文献   
94.
95.
96.
97.
98.
99.

BACKGROUND

Online physician rating websites are increasingly used by patients to evaluate their doctors. The purpose of this investigation was to evaluate factors associated with better spine surgeon ratings.

METHODS

Orthopedic spine surgeons were randomly selected from the North American Spine Society directory utilizing a random number generator. Surgeon profiles on three physician rating websites, namely, www.HealthGrades.com, www.Vitals.com, and www.RateMDs.com, were analyzed to gather qualitative and quantitative data on patients’ perceptions of the surgeons. Independent variables from the websites were analyzed in relation to overall physician or patient satisfaction rating. Comments were coded by subject into following three categories: professional competence, bedside manner, and practice characteristics.

RESULTS

A total of 250 surgeons were evaluated, and 92% (n=230) of these doctors had at least one rating among the three websites. The surgeons with a higher average rating had significantly better trust (p<.01), scheduling (p<.01), staff (p<.01), helpfulness (p<.01), and punctuality (p<.01) scores but significantly less experience (p<.05). A linear regression model for the average rating of each surgeon (R2 value=0.754) yielded only following three significant variables: trustworthiness (p<.01), experience match (p<.05), and the average number of negative comments on surgeon's professional competence (p<.05). Trustworthiness (β=0.749) was the strongest predictor variable of physician rating, followed by the number of negative professional competence comments (β=?0.132) and experience match (β=?0.112).

CONCLUSIONS

This investigation assessed spine surgeon online patient ratings and categorized factors that patients associate with quality care. Trustworthiness was the most significant predictor of positive ratings, whereas ease of scheduling, quality of staff, helpfulness, and punctuality were also associated with higher patient ratings. Understanding what patients value may help optimize care of spine surgery patients.  相似文献   
100.
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