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   2840篇
  免费   149篇
  国内免费   2篇
  2991篇
  2023年   38篇
  2022年   22篇
  2021年   48篇
  2020年   86篇
  2019年   80篇
  2018年   111篇
  2017年   107篇
  2016年   131篇
  2015年   79篇
  2014年   88篇
  2013年   319篇
  2012年   160篇
  2011年   162篇
  2010年   95篇
  2009年   90篇
  2008年   115篇
  2007年   126篇
  2006年   96篇
  2005年   94篇
  2004年   88篇
  2003年   74篇
  2002年   77篇
  2001年   64篇
  2000年   52篇
  1999年   51篇
  1998年   32篇
  1997年   30篇
  1996年   21篇
  1995年   16篇
  1994年   17篇
  1993年   19篇
  1992年   32篇
  1991年   28篇
  1990年   15篇
  1989年   14篇
  1988年   16篇
  1987年   17篇
  1986年   22篇
  1985年   18篇
  1984年   16篇
  1983年   15篇
  1981年   11篇
  1980年   13篇
  1979年   16篇
  1978年   12篇
  1977年   12篇
  1975年   17篇
  1974年   12篇
  1973年   14篇
  1966年   15篇
排序方式: 共有2991条查询结果,搜索用时 18 毫秒
1.
2.
3.
4.
Speakers in informal conversations tend to alternate regularly between lower and higher amounts of talking; the periods of these low/high activity cycles are on the order of 3, 6, and 15 minutes. Statistically significant periodicities occurred in 55% of the conversations studied. The periodograms that describe the partition of variance among periodic components whow consistent individual differences in the cyclic patterning of vocal activity. Discriminant analysis used the amount of variance accounted for by each of the 12 lowest-frequency periodic components as discriminating variables to see whether speakers could be identified on the basis of the cyclic patterns in vocal activity. Speakers were discriminated and classified at levels well above chance. This suggests that there are consistent individual differences among speakers in the length of cycles in amount of talk.We gratefully acknowledge support from the Central University Research Fund and from the office of the Dean of Liberal Arts at the University of New Hampshire.  相似文献   
5.
Effects of load (i.e., the number of stimuli in the display) have been observed in multiple-frame studies using a consistent mapping of stimuli to responses (e.g., Fisher, 1982, 1984). In a series of four experiments, it is shown that these effects are not the consequence of differences across the high- and low-load conditions in either decision noise or peripheral masking. Additionally, it is shown that of two modes of limited capacity (a limited-channel and divided-capacity model) considered as possible explanations of load effects in tasks where subjects are required to locate a target, only one--the limited-channel model--is consistent with the results from all three location tasks. Finally, it is argued that the limited-channel model predicts not only the behavior observed in the four consistent-mapping experiments reported in this article but also the behavior observed in several related consistent-mapping tasks (Kleiss & Lane, 1986; Shiffrin & Gardner, 1972).  相似文献   
6.
7.
There appears to be a strong relationship between mass media portrayals of violence and real-life violence itself. This article reviews the available literature on the effects of media treatment of sports violence; analyzes the theoretical explanations for this treatment; and makes proposals on how the problems of both sports violence and its media coverage may be remedied, with a particular focus on amateur hockey in Canada.  相似文献   
8.
Seventh-grade students and teachers from twenty-three middle and junior high schools were surveyed to determine the association between teacher attitudes, behavioral intentions, and smoking behavior and the prevalence of student smoking. Teacher attitudes toward smoking policies were found to be strongly related to the current smoking behavior of the teacher but not consistently related to student smoking. In addition, teacher likelihood of intervening showed a modest association with teacher smoking status, with current smokers generally indicating being the least likely to intervene for student possession or use of cigarettes. Teacher intentions to intervene were strongly associated with the prevalence of smoking among boys but not girls.  相似文献   
9.
Conditional stimuli (CS) associated with painful unconditional stimuli (US) produce a naloxone-reversible analgesia. The analgesia serves as a negative-feedback regulation of fear conditioning that can account for the impact of US intensity and CS predictiveness on Pavlovian fear conditioning. In Experiment 1 training under naloxone produced learning curves that approached the same high asymptote despite US intensity. Shifting drug treatment during acquisition had effects that paralleled US intensity shifts. In Experiment 3 naloxone reversed Hall-Pearce (1979) negative transfer using a contextual CS, indicating that conditional analgesia acquired during the CS-weak-footshock phase retards acquisition in the CS-strong-footshock phase. Experiment 5 used a tone CS in both a latent-inhibition and a negative-transfer procedure. Only negative transfer was blocked by naloxone. Therefore, negative transfer but not latent inhibition is mediated by a reduction of US processing.  相似文献   
10.
The current study investigates sources of between-subjects variation in asymmetry scores on visual half-field and dichotic listening tasks. For each of these presentation modalities, subjects were given multiple laterality tasks. Results indicate that about 50% of the between-subjects variations in asymmetry scores in each modality is attributable to individual differences in perceptual asymmetries that are not stimulus-specific, referred to as "characteristic perceptual asymmetries" in this paper. In addition, the question of whether individual differences in characteristic perceptual asymmetries are modality specific, modality general, or both was investigated by entering subjects' asymmetry scores from visual half-field and dichotic listening tasks into a principal component analysis. The results of this analysis indicate that there are both modality specific and modality general influences on subjects' characteristic perceptual asymmetries.  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