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   9474篇
  免费   993篇
  国内免费   18篇
耳鼻咽喉   60篇
儿科学   292篇
妇产科学   192篇
基础医学   1245篇
口腔科学   208篇
临床医学   1086篇
内科学   1793篇
皮肤病学   89篇
神经病学   747篇
特种医学   292篇
外国民族医学   1篇
外科学   1948篇
综合类   320篇
一般理论   13篇
预防医学   923篇
眼科学   167篇
药学   568篇
中国医学   7篇
肿瘤学   534篇
  2023年   84篇
  2022年   107篇
  2021年   227篇
  2020年   142篇
  2019年   211篇
  2018年   251篇
  2017年   191篇
  2016年   163篇
  2015年   198篇
  2014年   295篇
  2013年   412篇
  2012年   542篇
  2011年   561篇
  2010年   337篇
  2009年   274篇
  2008年   439篇
  2007年   491篇
  2006年   452篇
  2005年   407篇
  2004年   396篇
  2003年   380篇
  2002年   361篇
  2001年   225篇
  2000年   214篇
  1999年   194篇
  1998年   117篇
  1997年   105篇
  1996年   79篇
  1995年   80篇
  1994年   78篇
  1993年   57篇
  1992年   179篇
  1991年   173篇
  1990年   157篇
  1989年   126篇
  1988年   128篇
  1987年   106篇
  1986年   129篇
  1985年   117篇
  1984年   94篇
  1983年   82篇
  1982年   59篇
  1981年   50篇
  1979年   85篇
  1978年   77篇
  1976年   52篇
  1975年   55篇
  1974年   57篇
  1973年   73篇
  1972年   70篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
44.
Background: The effects of epidural needle design, angle, and bevel orientation on cerebrospinal fluid leak after puncture have not been reported. The impact of these factors on leak rate was examined using a dural sac model. Dural trauma was examined using scanning electron microscopy.

Methods: Human cadaveric dura, mounted on a cylindrical model, was punctured with epidural needles using a micromanipulator. Tissue was punctured at 15 cm H2O (left lateral decubitus) system pressure, and leak was measured at 25 cm H2O (semisitting) pressure. Leak rates and trauma were compared for the following: (1) six different epidural needles at 90[degrees], bevel parallel to the dural long axis; (2) 18-gauge Tuohy and 18-gauge Special Sprotte(R) epidural needles, 30[degrees]versus 90[degrees]; (3) 18-gauge Tuohy, bevel perpendicular versus parallel to the dural long axis.

Results: With the 90[degrees] puncture, bevel parallel, the greatest leak occurred with a 17-gauge Hustead (516 +/- 319 ml/15 min), and the smallest leak occurred with a 20-gauge Tuohy (100 +/- 112 ml/15 min; P = 0.0018). A 20-gauge Tuohy puncture led to statistically significant reductions in leak (P value range, 0.0001-0.0024) compared with all needles except the Special Sprotte(R). With the 30[degrees]versus 90[degrees] angle, 30[degrees] punctures with an 18-gauge Tuohy produced nonstatistically significant leak reductions compared with the 18-gauge Tuohy at 90[degrees]. The puncture angle made no difference for the Special Sprotte(R). Nonsignificant reductions were found for the Special Sprotte(R) compared with the Tuohy. With the 18-gauge Tuohy bevel orientation, perpendicular orientation produced nonstatistically significant reductions in leak compared with parallel orientation.  相似文献   

45.
A review of the international literature on staffing in childcare centres in five English language countries and Denmark reveals both remarkable similarities and interesting differences in the childcare workforce. The paper compares characteristics of the workforce; their training and professional membership. It also compares conditions of work in each country, including salaries, staff benefits, and features of the working environment such as job satisfaction and staff turnover. Findings indicate that childcare workers tend to be young and female; that a relatively high proportion of untrained staff work in childcare centres; that, except in Denmark, the level of extrinsic benefits is startlingly low. Workers are paid relatively little compared to the average pay for women in their countries but the workforce does not benefit from enhanced conditions of work to compensate for low pay. However, the level of intrinsic satisfaction with the work is high. Caring for children is a satisfying form of employment, even if it offers a limited career structure.  相似文献   
46.
Students (N = 377) from four Cape Town township high schools were surveyed to obtain information on their knowledge of and attitudes towards the acquired immunodeficiency syndrome (AIDS), and on their sexual behaviour. The study was undertaken to provide information for planning an AIDS education intervention. Three-quarters of students reported that they had had sexual intercourse. Most students had heard of AIDS, and the majority of these knew that it was infectious. More than half of the students were confused or lacked knowledge about the modes of transmission. Two-thirds of the students believed AIDS could be prevented, but knowledge of prevention strategies was superficial. Of the sexually active students only 11.4% had ever used a condom, and of all students 39.6% stated that they would use a condom in the future. Two-thirds of the students were not aware that there is no cure for AIDS. Students did not acknowledge that AIDS could affect them directly, and attributed the problem to prostitutes and 'promiscuous' people in 36.4% of responses, and to 'white' people in 23.8% of responses. Students expressed intolerance, fear and rejection of people with AIDS, and only 6.4% would accept an affected person into their class. Almost all the students wanted AIDS education at school, and most of these requested that the school nurse facilitate this education. It is concluded that appropriate AIDS prevention education is urgently required for both high school and junior school students.  相似文献   
47.
48.
49.
This data would suggest that psychiatric training programs may not be organized according to the interest or needs of many trainees. The emphasis on fulltime research in neurobiological psychiatry is centre stage in most programs, and yet according to our survey, few residents view this as a desirable career path. Our data from 8 years of trainees at the University of Toronto indicates that a new model of training streams would best suit the needs of the trainee, the profession and the community. This report is a continuation of a study into the recruitment process. An earlier report was published in the Canadian Journal of Psychiatry Vol. 29, December 1984. Our present data is on two groups of trainees as well as from faculty.  相似文献   
50.
This paper examines medical malpractice law as it applies to medically necessary oral health care. The basic legal concepts and reported cases involving medically necessary oral health care are reviewed. It is concluded that dental professionals and consumer advocates must advance their educational and legislative advocacy efforts so that health professional colleagues and the public will become aware of the importance of these services and insurers will routinely include coverage of medically necessary oral health care in their medical and dental policies. While failure to provide medically necessary oral health care can be violative of patient rights and legally actionable, medical malpractice litigation should always be the behavior modifier of last resort.  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