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   635篇
  免费   32篇
  国内免费   2篇
  2023年   2篇
  2022年   3篇
  2021年   8篇
  2020年   15篇
  2019年   13篇
  2018年   16篇
  2017年   27篇
  2016年   16篇
  2015年   9篇
  2014年   16篇
  2013年   82篇
  2012年   36篇
  2011年   39篇
  2010年   19篇
  2009年   22篇
  2008年   31篇
  2007年   25篇
  2006年   23篇
  2005年   22篇
  2004年   31篇
  2003年   22篇
  2002年   23篇
  2001年   14篇
  2000年   17篇
  1999年   8篇
  1998年   7篇
  1997年   10篇
  1996年   15篇
  1995年   15篇
  1994年   8篇
  1993年   4篇
  1992年   2篇
  1991年   7篇
  1990年   5篇
  1989年   3篇
  1988年   8篇
  1987年   6篇
  1986年   2篇
  1985年   4篇
  1984年   5篇
  1982年   3篇
  1981年   5篇
  1980年   6篇
  1979年   2篇
  1978年   3篇
  1977年   2篇
  1974年   2篇
  1973年   2篇
  1971年   1篇
  1961年   1篇
排序方式: 共有669条查询结果,搜索用时 15 毫秒
521.
Women and men are subject to different forms of human trafficking; sexual exploitation is more common for women than for men, and the purposes of trafficking follow gender roles. This article argues that Canadian immigration policies have differential and discriminatory impacts according to gender. We define human trafficking before critiquing two Canadian immigration programs that leave women vulnerable to exploitation. Interviews, questionnaires, and a review of official documents were employed in exploring the government's response to this phenomenon. Our findings suggest that given the nature of the international trafficking and exploitation of women in Canada, the government's focus on border control is ineffective in protecting trafficked women's human rights and the rights of migrants generally.  相似文献   
522.
523.
6-羟基多巴胺所致旋转行为的动物模型   总被引:1,自引:0,他引:1  
选用神经毒素(6-OHDA)造成动物大脑黑质纹状体的单侧性损伤,致使动物的大脑两半球机能显示不对称性。致伤后以可卡因诱发动物的旋转行为。 本实验共观察了成年的Holtzman种系雌性大白鼠43只。结果表明,有38例(88.37%)的多巴胺的耗竭率在85一100%,它们的伤情较为理想。但是,3只动物(6.98%)的多巴胺的耗竭率小于60%,2只动物(4.65%)的多巴胺的耗竭率在60—84%。 本文详细地介绍了如何制备和利用旋转仪自动记录动物的旋转行为,以及用高效液相色谱法测定大脑纹状体内多巴胺的含量。  相似文献   
524.
525.
Abstract— A recently published study (Hecht & Proffitt, 1995) reported that adults in Munich, Germany, whose occupations involved considerable experience with liquids in containers, were less accurate on Piaget's water-level task than were comparable adults in other occupations. The present study attempted to replicate that experiment with a North American sample, but using lighter controls. The resulting data and conclusions contrast with those of the original study and indicate instead, that individuals in occupations that provide much experience with liquids in containers (bartenders, waiters and waitresses) are, in fact, more accurate on two versions of the water level task than individuals of equivalent gender, age, and education in control occupations (salespeople, clerical worker). The data are discussed in terms of both the impact and the limit s of experience on spatial-task performance.  相似文献   
526.
Benzodiazepines can reduce anxiety, can have favorable effects upon sleep, and may diminish problems that interfere with patients' quality of life. On the other hand, these drugs can generate transient anterograde amnesia and may diminish aspects of task performance. Research on the impact of alprazolam and other “tranquilizing” drugs has generally focused on tasks that remain below the complex efforts of managerial or professional personnel. Alprazolam-induced reduction of anxiety under challenging conditions might aid complex task performance, yet anterograde amnesia might interfere. In the present research, managers participated in validated complex simulation tasks. In a double-blind, dual crossover design, placebo, 0.5 mg, or 1.0 mg alprazolam was administered on 2 occasions during the task day. Drug treatment diminished performance on measures that require sequential actions but improved performance on measures less subject to short term memory but more determined by long-term style of functioning. Thus, depending on task requirements, positive or negative alteration of performance might occur.  相似文献   
527.
528.
Speech samples were taken from 21 children aged 16–40 months covering a wide range of mean utterance length. Presence or absence of 14 grammatical morphemes in linguistic and nonlinguistic obligatory contexts was scored. Order of acquisition of the morphemes was determined using two different criteria. The rank-orderings obtained correlated very highly with a previously determined order of acquisition for three children studied longitudinally. Age did not add to the predictiveness of mean length of utterance alone for grammatical development in terms of which morphemes were correctly used. The approximately invariant order of acquisition for the fourteen morphemes is discussed in terms of three possible determinants of this order. Frequency of use in parental speech showed no correlation with order of acquisition, but grammatical and semantic complexity both correlated highly with acquisition order.This research was supported in part by PHS grant HD-02908 from the National Institute of Child Health and Development.  相似文献   
529.
Four groups of college-age women were used to determine the relationship between absence of father in childhood and adult self-concept and interpersonal relationships with men. Groups consisted of 15 father-present subjects who came from intact homes; 15 father-absent (FA) subjects with no older brothers who experienced the death of their father early in life; 15 FA subjects with no older brothers who experienced father loss due to divorce; and 12 FA subjects with one or more older brothers whose parents were divorced. The Tennessee Self-Concept Scale and a self-report questionnaire of modes of relating to men were the dependent variable measures. Results revealed no significant differences among groups in most areas of self-concept or interpersonal relationships with both older and age-peer men. Only in social self-concept and nurturance behavior with age-peer men were significant differences observed. Thus, only partial support of the hypotheses of differences was obtained. Reasons for the departure between earlier and present results are proposed.This article is based on a master's of arts thesis completed by the first author (now at the University of Utah) under the direction of the second author.  相似文献   
530.
Reaction times are often collected in order to study the durations of hypothesized subprocesses. In many important cases, reaction times are collected for a sequence of tasks in which the processing for one task is a subset of the processing required for the next in the sequence. Data of this sort have been analyzed by multiple-regression methods. Here we propose a more sophisticated moving average model for such data. We show that ordinary multiple-regression methods produce estimates that are consistent, but not efficient, and that the usual R2 statistic may provide a misleading impression of goodness of fit. One consequence of the suggested statistical model is that it allows the same quantity of data to be used to fit a psychological model to a larger range of tasks.  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