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   1209339篇
  免费   84969篇
  国内免费   3063篇
耳鼻咽喉   15764篇
儿科学   40907篇
妇产科学   32752篇
基础医学   175122篇
口腔科学   32997篇
临床医学   107439篇
内科学   239829篇
皮肤病学   28408篇
神经病学   98083篇
特种医学   44811篇
外国民族医学   388篇
外科学   175926篇
综合类   24896篇
一般理论   450篇
预防医学   97284篇
眼科学   26774篇
药学   86546篇
  7篇
中国医学   2749篇
肿瘤学   66239篇
  2021年   10368篇
  2019年   11047篇
  2018年   17430篇
  2017年   12794篇
  2016年   13938篇
  2015年   15725篇
  2014年   19894篇
  2013年   30587篇
  2012年   43699篇
  2011年   45610篇
  2010年   25917篇
  2009年   23060篇
  2008年   41409篇
  2007年   43984篇
  2006年   43406篇
  2005年   41951篇
  2004年   40435篇
  2003年   38379篇
  2002年   36698篇
  2001年   51834篇
  2000年   52997篇
  1999年   44658篇
  1998年   12022篇
  1997年   10771篇
  1996年   10769篇
  1995年   10337篇
  1994年   9586篇
  1993年   8947篇
  1992年   34798篇
  1991年   33749篇
  1990年   33184篇
  1989年   31852篇
  1988年   29096篇
  1987年   29086篇
  1986年   27163篇
  1985年   26141篇
  1984年   19537篇
  1983年   16458篇
  1982年   9858篇
  1979年   17881篇
  1978年   12942篇
  1977年   10986篇
  1976年   10304篇
  1975年   10858篇
  1974年   13181篇
  1973年   12721篇
  1972年   11681篇
  1971年   10914篇
  1970年   10148篇
  1969年   9528篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
Objective: To assess the quality of images and video clips of fetal central nervous (CNS) structures obtained by ultrasound and transmitted via tele-ultrasound from Brazil to Australia.

Methods: In this cross-sectional study, 15 normal singleton pregnant women between 20 and 26 weeks were selected. Fetal CNS structures were obtained by images and video clips. The exams were transmitted in real-time using a broadband internet and an inexpensive video streaming device. Four blinded examiners evaluated the quality of the exams using the Likert scale. We calculated the mean, standard deviation, mean difference, and p values were obtained from paired t tests.

Results: The quality of the original video clips was slightly better than that observed by the transmitted video clips; mean difference considering all observers = 0.23 points. In 47/60 comparisons (78.3%; 95% CI?=?66.4–86.9%) the quality of the video clips were judged to be the same. In 182/240 still images (75.8%; 95% CI?=?70.0–80.8%) the scores of transmitted image were considered the same as the original.

Conclusion: We demonstrated that long distance tele-ultrasound transmission of fetal CNS structures using an inexpensive video streaming device provided images of subjective good quality.  相似文献   
73.
74.
Patients have become increasingly well informed with higher expectations to be involved in decision-making processes regarding their care and treatment. However, few studies have examined the impact of patient involvement on health care providers’ partnership-building communication. The aim of this study was to measure and explore the self-reported effects of patient involvement on the work of physicians and nurses. A questionnaire survey was distributed among cardiology staff in 12 Swedish hospitals (N = 488, response rate 67%). The sample was comprised of registered nurses (RNs, n = 303), licensed practical nurses (LPNs, n = 132), and physicians (MDs, n = 53). Confirmatory factor analysis was used to examine seven questionnaire statements concerning implications of patient involvement for one’s clinical work. Regression analyses were used to examine factors associated with staff’s partnership-building communication. Analysis confirmed two distinct factors accounting for 57% of the total variance, representing both negative—“Hassles”and positive—“Uplifts”aspects of patient involvement. Regression analyses revealed that only positive aspects (i.e., uplifts) of patient involvement predicted staff behavior aimed at involving patients. Working with actively involved patients may be a source of stress, both negative and positive, for health care professionals. By developing work routines for involving patients in their care, health care workplaces may help health care professionals to buffer the negative effects, and enhance the positive effects, of that stress.  相似文献   
75.
We evaluated RNA stability of Ebola virus in EDTA blood and urine samples collected from infected patients and stored in West Africa’s environmental conditions. In blood, RNA was stable for at least 18 days when initial cycle threshold values were <30, but in urine, RNA degradation occurred more quickly.  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