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   175198篇
  免费   7803篇
  国内免费   156篇
  2021年   1503篇
  2020年   2786篇
  2019年   3452篇
  2018年   3541篇
  2017年   3996篇
  2016年   4647篇
  2015年   3941篇
  2014年   4818篇
  2013年   23546篇
  2012年   4569篇
  2011年   3754篇
  2010年   3946篇
  2009年   4781篇
  2008年   3976篇
  2007年   3495篇
  2006年   4086篇
  2005年   4055篇
  2004年   3532篇
  2003年   3196篇
  2002年   2978篇
  2001年   3513篇
  2000年   3377篇
  1999年   3292篇
  1998年   2860篇
  1997年   2681篇
  1996年   2579篇
  1995年   2421篇
  1994年   2383篇
  1993年   2350篇
  1992年   2707篇
  1991年   2554篇
  1990年   2396篇
  1989年   2305篇
  1988年   2275篇
  1987年   2282篇
  1986年   2250篇
  1985年   2493篇
  1984年   2556篇
  1983年   2311篇
  1982年   2389篇
  1981年   2355篇
  1980年   2186篇
  1979年   2212篇
  1978年   2206篇
  1977年   2172篇
  1976年   1948篇
  1975年   2024篇
  1974年   2072篇
  1973年   1954篇
  1972年   1545篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
281.
282.
283.
284.
285.
286.
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   
287.
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   
288.
289.
This study examined information communication technologies and workplace friendship dynamics. Employees reported factors that influenced their initiation of friendship with a coworker and reported patterns and perceptions of communication with their workplace friend via different communication methods. Results indicated that personality, shared tasks, and perceived similarity are the most important factors to coworker friendship initiation, and the importance of physical proximity to workplace friendship is diminishing in the electronically connected workplace. Results confirm the primacy of face‐to‐face interaction for workplace friendship initiation and maintenance. E‐mail, phone, and texting were also central to communication among workplace friends. The amount of time spent telecommuting affected workplace friendship initiation and communication. Finally, generational differences were identified with respect to Internet‐based communication methods.  相似文献   
290.
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   
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