全文获取类型
收费全文 | 3626篇 |
免费 | 672篇 |
国内免费 | 405篇 |
专业分类
4703篇 |
出版年
2024年 | 20篇 |
2023年 | 90篇 |
2022年 | 131篇 |
2021年 | 142篇 |
2020年 | 246篇 |
2019年 | 180篇 |
2018年 | 178篇 |
2017年 | 166篇 |
2016年 | 153篇 |
2015年 | 150篇 |
2014年 | 149篇 |
2013年 | 396篇 |
2012年 | 147篇 |
2011年 | 182篇 |
2010年 | 110篇 |
2009年 | 166篇 |
2008年 | 152篇 |
2007年 | 164篇 |
2006年 | 167篇 |
2005年 | 129篇 |
2004年 | 120篇 |
2003年 | 112篇 |
2002年 | 93篇 |
2001年 | 71篇 |
2000年 | 78篇 |
1999年 | 66篇 |
1998年 | 56篇 |
1997年 | 70篇 |
1996年 | 55篇 |
1995年 | 54篇 |
1994年 | 67篇 |
1993年 | 46篇 |
1992年 | 44篇 |
1991年 | 36篇 |
1990年 | 29篇 |
1989年 | 21篇 |
1988年 | 20篇 |
1987年 | 35篇 |
1986年 | 31篇 |
1985年 | 37篇 |
1984年 | 38篇 |
1983年 | 33篇 |
1982年 | 34篇 |
1981年 | 32篇 |
1980年 | 28篇 |
1979年 | 32篇 |
1978年 | 28篇 |
1977年 | 51篇 |
1976年 | 41篇 |
1975年 | 26篇 |
排序方式: 共有4703条查询结果,搜索用时 0 毫秒
241.
Pigeons attack or threaten animate and inanimate targets. The assessment of their aggressiveness was studied by exposing them in their home cages to three different stimuli: the experimenter's hand, a live pigeon, and a rear-projected conspecific image when the birds were exposed to intermittent access to food. A positive correlation between the hand test and live pigeon test was evident, but no relationship between either of these responses and the response to a pictorial image was observed. These results combined with other ethological observations cast doubts on the usefulness of schedule-induced responses to pictorial targets in the assessment of the individual aggressiveness in pigeons, but suggest that the hand test is an adequate and reliable procedure for such evaluations. 相似文献
242.
Female rats, chronically treated with Testosterone Propionate (TP), were injected with Fluprazine (DU 27716) or saline and tested for social aggression, masculine and feminine sexual behavior. Fluprazine-treated females were less aggressive than saline-treated females, as indicated by a shift from offensive to less offensive parameters of aggression. At the same time, mounting in Fluprazine-treated females was almost totally abolished, both in aggression tests and in tests for sexual behavior. Feminine sexual responses increased during aggressive encounters but were slightly inhibited when females were confronted with sexually active males. Females treated with Fluprazine and tested for mounting with a receptive female showed a substantial increase of offensive aggression directed at the receptive stimulus female. It is concluded that Fluprazine does not selectively inhibit offensive aggression in TP-treated female rats. 相似文献
243.
244.
The development of prosocial behavior is traced from middle childhood to adulthood in a 22-year longitudinal study of 800 children first seen at age 8 and is compared to the development of aggression over the same period. Prosocial behavior and aggression seem to represent opposite ends of a single dimension of behavior since they are consistently negatively related to each other and relate in opposite ways to correlated variables both synchronously and over time. Both are stable forms of behavior with good predictability over the time span studied and both are related to the quality of the parent-child relationship. The most important deterrent to the development of antisocial behavior and the encouragement of prosocial behavior is probably a close identification between the child and his/her parents. 相似文献
245.
Supporting decision-making processes when the elements of a group are geographically dispersed and on a tight schedule is a complex task. Aiming to support decision-makers anytime and anywhere, Web-based group decision support systems have been studied. However, the limitations in the decision-makers’ interactions associated to this scenario bring new challenges. In this work, we propose a set of behavioral styles from which decision-makers’ intentions can be modelled into agents. The goal is that, besides having agents represent typical preferences of the decision-makers (towards alternatives and criteria), they can also represent their intentions. To do so, we conducted a survey with 64 participants in order to find homogeneous operating values so as to numerically define the proposed behavioral styles in four dimensions. In addition, we also propose a communication model that simulates the dialogues made by decision-makers in face-to-face meetings. We developed a prototype to simulate decision scenarios and found that agents are capable of acting according to the decision-makers’ intentions and fundamentally benefit from different possible behavioral styles, just as a face-to-face meeting benefits from the heterogeneity of its participants. 相似文献
246.
This paper investigates the salience of social-psychological factors in explaining why drivers purchase (or fail to purchase) New Energy Vehicles (NEVs)—including hybrid electric vehicles, battery electric vehicles, and fuel cell electric vehicles—in China. A questionnaire measuring six dimensions (including attitudes, subjective norms, perceived behavioral control, personal norms, low-carbon awareness and policy) was distributed in Tianjin, where aggressive policy incentives for NEVs exist yet adoption rates remain low. Correlation analysis and hierarchical multiple regression analyses are applied data collected through 811 valid questionnaires. We present three main findings. First, there is an “awareness-behavior gap” whereby low-carbon awareness has a slight moderating effect on purchasing behavior via psychological factors. Second, subjective norms has a stronger influence on intention to purchase New Energy Vehicles than other social-psychological factors. Third, acceptability of government policies has positive significant impact on adoption of New Energy Vehicles, which can provide reference potential template for other countries whose market for New Energy Vehicles is also in an early stage. 相似文献
247.
The purpose of this study was to determine the effects of teacher feedback delivered via a public address system on the off-task behavior of elementary-school physical education students. A multiple baseline design across three classes was used in this investigation. Results indicated a consistent decline in off-task behavior when the public address feedback system was used. 相似文献
248.
Critchfield TS 《Journal of applied behavior analysis》2002,35(4):423-426
Analysis of scholarly citations involving behavioral journals reveals that, consistent with its mission, applied behavior analysis research frequently references the basic behavioral literature but, as some have suspected, exerts narrow scholarly influence. 相似文献
249.
250.
Crown CL Feldstein S Jasnow MD Beebe B Jaffe J 《Journal of psycholinguistic research》2002,31(1):1-23
The purpose of this study was to examine the hypothesis that 6-week-old infants are capable of coordinated interpersonal timing within social interactions. Coordinated interpersonal timing refers to changes in the timing of one individual's behavior as a function of the timing of another individual's behavior. Each of 45, first-born 6-week-old infants interacted with his or her mother and a stranger for a total of 14 minutes. The interactions were videotaped and coded for the gaze behavior of the infants and the vocal behavior of the mothers and strangers. Time-series regression analyses were used to assess the extent to which the timing of each of the infants' gazes was coordinated with the timing of the adults' vocal behavior. The results revealed that (a) coordinated timing occurs between infants and their mothers and between infants and strangers as early as when infants are 6 weeks old, and (b) strangers coordinated the timing of their pauses with the infants to a greater extent than did mothers. The findings are discussed in terms of the role of temporal sensitivity in social interaction. 相似文献