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   32091篇
  免费   1828篇
  国内免费   101篇
耳鼻咽喉   251篇
儿科学   1092篇
妇产科学   915篇
基础医学   3582篇
口腔科学   412篇
临床医学   5829篇
内科学   5309篇
皮肤病学   345篇
神经病学   3178篇
特种医学   659篇
外国民族医学   1篇
外科学   3103篇
综合类   295篇
现状与发展   1篇
一般理论   50篇
预防医学   4478篇
眼科学   448篇
药学   1915篇
中国医学   33篇
肿瘤学   2124篇
  2023年   194篇
  2022年   327篇
  2021年   588篇
  2020年   421篇
  2019年   651篇
  2018年   808篇
  2017年   562篇
  2016年   640篇
  2015年   677篇
  2014年   994篇
  2013年   1603篇
  2012年   2298篇
  2011年   2440篇
  2010年   1292篇
  2009年   1136篇
  2008年   2203篇
  2007年   2394篇
  2006年   2280篇
  2005年   2215篇
  2004年   2038篇
  2003年   1962篇
  2002年   1876篇
  2001年   235篇
  2000年   195篇
  1999年   288篇
  1998年   376篇
  1997年   326篇
  1996年   246篇
  1995年   277篇
  1994年   215篇
  1993年   212篇
  1992年   136篇
  1991年   140篇
  1990年   135篇
  1989年   119篇
  1988年   106篇
  1987年   105篇
  1986年   98篇
  1985年   108篇
  1984年   129篇
  1983年   129篇
  1982年   151篇
  1981年   142篇
  1980年   120篇
  1979年   63篇
  1978年   74篇
  1977年   62篇
  1976年   47篇
  1975年   37篇
  1974年   40篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Journal of Behavioral Medicine - Evidence supports the use of graphic warnings to educate the public about the health harms of smoking and suggests warnings eliciting negative emotional responses...  相似文献   
2.
3.
4.
5.
Purpose: To describe how central venous access devices (CVADs) are utilized for ambulatory oncology patients and to evaluate the rate of complications. Method: Single institution retrospective study of oncology patients with CVADs who received systemic treatment at the Walker Family Cancer Centre (WFCC) between 1 January and 31 December 2018. Results: A total of 480 CVADS were placed in 305 patients, of which 408 (85%) were peripherally inserted central catheters (PICCs) and 72 (15%) were implanted vascular access devices (PORTs). The incidence of early and late complications was 9% and 24%, respectively. For the entire cohort, the rate of venous thromboembolism (VTE) was 16%, of which 9% were CVAD-related thrombosis (CRTs) and 7% were distant VTE. The CRT rates were similar for PICCs and PORTs (9% vs. 7%). A total of 6% of CVADs were complicated by infection (i.e., localized infections and bacteremia), with a total infection rate of 0.43 and 0.26 per 1000 indwelling days for PICCs and PORTs, respectively. The incidence of central line associated bloodstream infections (CLABSI) was greater for PICCs than PORTs, at a rate of 0.22 compared with 0.08 per 1000 indwelling days, respectively. The premature catheter removal rate was 26% for PICCs and 18% for PORTs. PORTs required more additional hospital visits. Conclusions: PICCs were utilized more frequently than PORTs and had a higher rate of premature removal. The rates of VTE and CRT were similar for both CVAD types. PORTs had a lower rate of infection per 1000 indwelling days. However, the management of PORT related complications required more visits to the hospital and oncology clinic.  相似文献   
6.
7.
8.
9.
10.
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   
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