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   199198篇
  免费   2449篇
  国内免费   135篇
耳鼻咽喉   1367篇
儿科学   7076篇
妇产科学   3658篇
基础医学   19533篇
口腔科学   2615篇
临床医学   14201篇
内科学   37138篇
皮肤病学   1475篇
神经病学   18452篇
特种医学   9593篇
外科学   32138篇
综合类   2454篇
一般理论   2篇
预防医学   19701篇
眼科学   3230篇
药学   10729篇
中国医学   752篇
肿瘤学   17668篇
  2023年   246篇
  2022年   548篇
  2021年   938篇
  2020年   546篇
  2019年   820篇
  2018年   22792篇
  2017年   17880篇
  2016年   20062篇
  2015年   1644篇
  2014年   1884篇
  2013年   2152篇
  2012年   8877篇
  2011年   22886篇
  2010年   19762篇
  2009年   12418篇
  2008年   20950篇
  2007年   23093篇
  2006年   1969篇
  2005年   3448篇
  2004年   4538篇
  2003年   5255篇
  2002年   3396篇
  2001年   488篇
  2000年   619篇
  1999年   376篇
  1998年   387篇
  1997年   323篇
  1996年   215篇
  1995年   218篇
  1994年   180篇
  1993年   122篇
  1992年   190篇
  1991年   208篇
  1990年   244篇
  1989年   177篇
  1988年   160篇
  1987年   127篇
  1986年   108篇
  1985年   123篇
  1984年   96篇
  1983年   77篇
  1982年   76篇
  1981年   54篇
  1980年   97篇
  1979年   59篇
  1976年   51篇
  1974年   64篇
  1938年   62篇
  1932年   61篇
  1930年   53篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
For persons battling HIV/AIDS a stable place to live may decide the length and quality of life itself. It is nearly impossible for a person on the streets to engage in a needed continuous AIDS treatment regimen when the very basic question of where that person will rest his or her head when darkness comes in just a few hours is unresolved. When danger lurks on the streets, when cold numbs the limbs, when tiredness overwhelms the mind, when fear breaks the spirit, a place to call home would make all the difference.  相似文献   
73.
74.
Abstract Objective: To define the diagnostic accuracy of clinical examination in patients with impaired consciousness or endotracheal intubation to detect pelvic ring fractures and to identify those with severe bleeding. Methods: Included in this prospective data collection with retrolective data analysis were a consecutive series of blunt trauma victims with either a Glasgow Coma Scale ≤ 13 or tracheal intubation. Clinical examination comprised testing for stability of the iliac wings. Results: From 784 subjects (injury severity score 23.3 ± 17.4) 93 patients (11.9%) were found to have a pelvic ring fracture. Clinical instability of the pelvic ring was found in 42 patients. There was only one false positive. Fifty-two fractures could not be identified by clinical examination, including nine fractures (17%) that required surgical fracture stabilization (sensitivity of clinical examination 44.1%). Seventeen fractures (18.3%) were associated with a blood loss larger than 20% of circulating blood volume. Sixteen of those were identified by clinical instability of the pelvic ring (sensitivity 94.1%, specificity 97.0%, positive predictive value 38.1%, negative predictive value 99.9%). Conclusions: Clinical examination for stability of the pelvis in this selected group of patients missed a significant number of pelvic ring fractures including fractures that require surgical stabilization. The finding of a clinically unstable identifies most of the patients with the pelvic ring fracture being a major source of bleeding. A stable pelvis makes pelvic ring fracture as being the source of bleeding quite unlikely.  相似文献   
75.

Background  

Reports on childhood cancer survivors estimated cumulative probability of developing secondary neoplasms vary from 3,3% to 25% at 25 years from diagnosis, and the risk of developing another cancer to several times greater than in the general population.  相似文献   
76.
Elias Hakalehto   《Pathophysiology》2006,13(4):257-267
Potentially dangerous antibiotic resistant contaminants have permanently penetrated at least well-off western populations. The danger is so evident that some hospitals have started to refuse accepting patients who carry such bacteria. Sampling and enrichment measures in hygiene monitoring must be updated as they are corner stones in handling the problems and safeguarding the health care units. Their patients, when exposed to microorganisms are strenuous to treat. Sometimes even this fails, if the infections are spreading in weakened patients. The present review summarizes currently used technologies and the abilities of bacteria to avoid detection. Improved protocols on environmental monitoring in healthcare units are required. They should be comparable with contamination control in industries. Actually these measures in health care should be even stricter because human lives are directly endangered as the resistance of especially elderly patients is low.  相似文献   
77.
78.

Background  

It is well known that physicians' night-call duty may cause impaired performance and adverse effects on subjective health, but there is limited knowledge about effects on sleep duration and recovery time. In recent years occupational stress and impaired well-being among anaesthesiologists have been frequently reported for in the scientific literature. Given their main focus on handling patients with life-threatening conditions, when on call, one might expect sleep and recovery to be negatively affected by work, especially in this specialist group. The aim of the present study was to examine whether a 16-hour night-call schedule allowed for sufficient recovery in anaesthesiologists compared with other physician specialists handling less life-threatening conditions, when on call.  相似文献   
79.
Associations between street connectivity and active transportation   总被引:1,自引:0,他引:1  

Background  

Past studies of associations between measures of the built environment, particularly street connectivity, and active transportation (AT) or leisure walking/bicycling have largely failed to account for spatial autocorrelation of connectivity variables and have seldom examined both the propensity for AT and its duration in a coherent fashion. Such efforts could improve our understanding of the spatial and behavioral aspects of AT. We analyzed spatially identified data from Los Angeles and San Diego Counties collected as part of the 2001 California Health Interview Survey.  相似文献   
80.

Objective  

To test the effects of the use of a collapsible, portable chair (chair B), as opposed to a ‘standard’ chair (chair A), on the outcome of the timed “Up and Go” (TUG) test.  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