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   184113篇
  免费   8138篇
  国内免费   155篇
  192406篇
  2020年   2783篇
  2019年   3453篇
  2018年   3751篇
  2017年   4113篇
  2016年   4780篇
  2015年   3940篇
  2014年   4803篇
  2013年   23460篇
  2012年   5085篇
  2011年   4335篇
  2010年   4101篇
  2009年   4885篇
  2008年   4433篇
  2007年   3992篇
  2006年   4432篇
  2005年   4308篇
  2004年   3881篇
  2003年   3470篇
  2002年   3257篇
  2001年   4029篇
  2000年   3783篇
  1999年   3553篇
  1998年   2883篇
  1997年   2699篇
  1996年   2621篇
  1995年   2447篇
  1994年   2411篇
  1993年   2369篇
  1992年   2916篇
  1991年   2723篇
  1990年   2562篇
  1989年   2479篇
  1988年   2436篇
  1987年   2404篇
  1986年   2421篇
  1985年   2663篇
  1984年   2649篇
  1983年   2406篇
  1982年   2405篇
  1981年   2367篇
  1980年   2214篇
  1979年   2356篇
  1978年   2264篇
  1977年   2209篇
  1976年   2022篇
  1975年   2097篇
  1974年   2191篇
  1973年   2070篇
  1972年   1664篇
  1971年   1599篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
191.
192.
193.
194.
195.
Recent studies demonstrating that multiple meanings of an ambiguous word are initially accessed even when only one reading is syntactically appropriate with the preceding context can be criticized on at least two grounds. First, many of the syntactic contexts used were not truly restrictive, and, secondly, subjects may not have had time to integrate the context before processing the ambiguous word. In the present study, subjects listened to a sentence ending in an ambiguous word and then made a lexical decision to a target related to either the appropriate or inappropriate reading. Contexts were completely restrictive, and a pause was introduced between the context and the ambiguous word. Multiple access still obtained, providing further support for the claim that lexical access is not guided by syntactic context.  相似文献   
196.
Suicides among older adults in the United States and Canada in the last decade have accounted for an increasing share of all suicides. In both countries the use of firearms among older adults has steadily increased. Despite these trends, little is known about the extent to which crisis centers are prepared to prevent elder suicide. A survey of AAS-listed crisis prevention centers examined the training, knowledge, and current practices relevant to elder suicide among personnel in 321 crisis prevention centers in both countries. Results revealed insufficient training, a lack of familiarity with recent suicide trends, and limited outreach to older adults.  相似文献   
197.
198.
Cancellation tests are commonly used in the clinical assessment of visuospatial function, but there has been little study of task characteristics influencing performance. This study was designed to assess factors which affect cancellation performance. Sixteen healthy subjects sequentially performed four random-array letter cancellation tasks. The forms contained 50 and 100 stimuli and target:distractor (T/D) ratios of 1:4 and 1:9 with target letter “A” and randomly selected letter distractors. The primary performance measure was calculated as the number of correctly cancelled targets divided by the time to complete the task, corrected for accuracy. This measure revealed a strong effect of T/D ratio (p< .0001), with performance adversely affected by higher proportion of distractors. There was no effect of stimulus number. This suggests that T/D ratio should be considered in cancellation test design and interpretation.  相似文献   
199.
200.
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