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   18864篇
  免费   1186篇
  国内免费   84篇
耳鼻咽喉   182篇
儿科学   625篇
妇产科学   417篇
基础医学   2496篇
口腔科学   371篇
临床医学   2189篇
内科学   4444篇
皮肤病学   531篇
神经病学   1892篇
特种医学   412篇
外科学   1456篇
综合类   101篇
一般理论   8篇
预防医学   1933篇
眼科学   303篇
药学   1282篇
中国医学   69篇
肿瘤学   1423篇
  2023年   152篇
  2022年   270篇
  2021年   546篇
  2020年   329篇
  2019年   526篇
  2018年   643篇
  2017年   405篇
  2016年   484篇
  2015年   552篇
  2014年   770篇
  2013年   994篇
  2012年   1562篇
  2011年   1587篇
  2010年   823篇
  2009年   786篇
  2008年   1295篇
  2007年   1284篇
  2006年   1247篇
  2005年   1241篇
  2004年   1060篇
  2003年   1025篇
  2002年   936篇
  2001年   93篇
  2000年   82篇
  1999年   134篇
  1998年   160篇
  1997年   146篇
  1996年   140篇
  1995年   107篇
  1994年   79篇
  1993年   93篇
  1992年   64篇
  1991年   38篇
  1990年   41篇
  1989年   42篇
  1988年   26篇
  1987年   22篇
  1986年   35篇
  1985年   36篇
  1984年   31篇
  1983年   29篇
  1982年   30篇
  1981年   33篇
  1980年   35篇
  1979年   17篇
  1978年   15篇
  1976年   12篇
  1975年   9篇
  1974年   11篇
  1973年   11篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
861.
862.
863.
864.
The purpose of this study was to compare the performance of four power wheelchairs when used by children to perform a variety of indoor activities. Eight boys and eight girls performed a series of 11 functional tasks when positioned in each of four different power wheelchairs reflecting different design classes. There were no significant differences for many of the dependent variables. However, the Everaid Turbo was significantly better for functional positioning at a standard kitchen table and at school desks and for accessing objects at different heights. By contrast the Invacare Jaguar was better for straight-line driving speed. Other findings include children's subjective impressions of the four power wheelchairs.  相似文献   
865.
Adult male and female CD rats (F0) were dosed with glutaraldehyde (GA; CAS number 111-30-8) in drinking water at concentrations of 0 (controls), 50, 250, or 1000 ppm for a 10-wk prebreed period and through mating, gestation, and lactation. Resultant Fl offspring, selected to be parents of the next generation, were continued on the same regime from prebreed through lactation. Twenty-eight parental animals per sex per generation for each dose group were evaluated for clinical signs, body weight (absolute and gain), and water and food consumption. The offspring were evaluated for survival and body weight to weaning. Necropsy and light microscopic examination of removed tissues were conducted in all F0 and F1  相似文献   
866.
867.
We describe Guatemalan birth attendants’ identification of vulnerable newborns, their evaluation of gestational age and anthropometry, and the validity of the Capurro and New Ballard newborn gestational age assessment methods. We interviewed 49 birth attendants and trained 10 of these women to assess 63 newborns. The Capurro and Ballard methods were correlated (Spearman rho = .75, p < .001) and showed agreement (Bland-Altman plot, difference and bias, ?0.33 ± 1.3 weeks). Prematurity was estimated at 27% (Ballard) and 24% (Capurro); low birth weight (LBW) was 30%. Capurro provided a simplified, equivalent estimate of gestational age compared with New Ballard that could be used by birth attendants.  相似文献   
868.
869.
Objective: The prevalence of abnormal behavioural responses to a variety of stimuli among individuals with autism has led researchers to examine whether physiological reactivity (PR) is typical in this population. This article reviewed studies assessing PR to sensory, social and emotional, and stressor stimuli in individuals with autism. Methods: Systematic searches of electronic databases identified 57 studies that met our inclusion criteria. Studies were analysed to determine: (a) participant characteristics; (b) physiological measures used; (c) PR to sensory, social and emotional or stressor stimuli; (d) the relation between PR and behavioural or psychological variables and (e) baseline physiological activity. A novel measure of methodological quality suitable for use with non-randomized, non-interventional, psychophysiological studies was also developed and applied. Results: Individuals with autism were found to respond differently than typically developing controls in 78.6%, 66.7% and 71.4% of sensory, social and emotional, and stressor stimulus classes, respectively. However, this extant literature is characterized by variable and inconsistent findings, which do not appear to be accounted for by varying methodological quality, making it difficult to determine what specific factors differentiate individuals with autism who present with atypical PR from those who do not. Conclusions: Despite this uncertainty, individual differences in PR are clearly present in autism, suggesting additional research is needed to determine the variables relating to PR among those with ASD and to examine the possible existence of physiological subtype responders in the population.  相似文献   
870.
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