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   25718篇
  免费   257篇
  2023年   44篇
  2022年   30篇
  2021年   48篇
  2020年   113篇
  2019年   113篇
  2018年   3590篇
  2017年   2921篇
  2016年   2404篇
  2015年   329篇
  2014年   197篇
  2013年   678篇
  2012年   808篇
  2011年   2656篇
  2010年   2660篇
  2009年   1655篇
  2008年   1919篇
  2007年   2401篇
  2006年   242篇
  2005年   424篇
  2004年   389篇
  2003年   345篇
  2002年   263篇
  2001年   139篇
  2000年   149篇
  1999年   118篇
  1998年   125篇
  1997年   97篇
  1996年   87篇
  1995年   77篇
  1994年   86篇
  1993年   56篇
  1992年   73篇
  1991年   43篇
  1990年   62篇
  1989年   35篇
  1988年   25篇
  1987年   38篇
  1986年   37篇
  1985年   42篇
  1984年   35篇
  1983年   54篇
  1982年   43篇
  1981年   35篇
  1980年   34篇
  1979年   42篇
  1978年   44篇
  1977年   27篇
  1976年   31篇
  1974年   19篇
  1972年   15篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
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   
22.
23.
24.
25.
26.
This paper reports the operation of robust attentional bias to the top and right during perception of small, single geometric forms. Same/different judgements of successively presented standard and comparison forms are faster when local differences are located at top and right rather than in other regions of the forms. The bias persists when form size is reduced to approximately one degree of visual angle, and it is unaffected by saccadic eye movements and by instructions to attend to other reliably differentiating regions of the forms. Results lend support in various degrees to two of the possible explanations of the bias: (1) a static, skewed distribution of attentional resources around eye fixation; and (2) biased, covert scanning that commences invariably at the top and right of stim ulus forms. Origins of the bias in terms of possible left-hemispheric capacity for constructing representations of visual stimuli from parts, as well as in terms of reading experience and prevailing optic flow during locomotion through space are considered. Recent investigations of conditions under which the bias can be maintained or reduced are mentioned.  相似文献   
27.
28.
29.
Missing body homicide cases have gained public interest globally due to some high-profile cases. In many of these cases, the task of locating the victim's remains relies on the information investigators can gain through the interviewing of willing suspects. To date, investigative interviewing research has largely focused on the retrieval of episodic memory (events) without focusing on spatial memory, a prominent cognitive task required in locating a victim's remains. The current experiment tests the enhanced cognitive interview (ECI) against a free recall strategy in a mock homicide scenario where participants are required to hide and retrieve an object in a natural bushland setting. The results showed that those in the ECI condition produced more coarse- and fine-grained details of landmarks and their actions at and journeying to the deposition site. This demonstrates the value of using the ECI in generating more valuable information to assist in successive search attempts.  相似文献   
30.
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