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   694篇
  免费   57篇
  751篇
  2023年   5篇
  2021年   11篇
  2020年   11篇
  2019年   13篇
  2018年   30篇
  2017年   21篇
  2016年   28篇
  2015年   17篇
  2014年   24篇
  2013年   61篇
  2012年   21篇
  2011年   35篇
  2010年   13篇
  2009年   24篇
  2008年   30篇
  2007年   30篇
  2006年   27篇
  2005年   23篇
  2004年   27篇
  2003年   13篇
  2002年   20篇
  2001年   12篇
  2000年   8篇
  1999年   25篇
  1998年   5篇
  1997年   11篇
  1996年   5篇
  1995年   5篇
  1992年   10篇
  1991年   6篇
  1989年   8篇
  1987年   5篇
  1986年   5篇
  1985年   8篇
  1984年   9篇
  1983年   5篇
  1982年   8篇
  1981年   8篇
  1980年   5篇
  1979年   6篇
  1978年   5篇
  1977年   5篇
  1975年   5篇
  1974年   5篇
  1969年   7篇
  1968年   14篇
  1966年   10篇
  1965年   6篇
  1964年   7篇
  1961年   7篇
排序方式: 共有751条查询结果,搜索用时 15 毫秒
131.
When mobile organisms are spatially disoriented, for instance by rapid repetitive movement, they must re-establish orientation. Past research has shown that the geometry of enclosing spaces is consistently used for reorientation by a wide variety of species, but that non-geometric features are not always used. Based on these findings, some investigators have postulated a species-universal 'geometric module' that is transcended by the acquisition of spatial language at 6 years. This conclusion has been challenged, however, by findings that children as young as 18 months actually do use features to reorient in larger enclosures than those used in the original experiments. The reason for the room size effect is explored here in five experiments. Collectively, the data on age at which features are first used point to the importance of both restriction of movement in the small space and the fact that features are closer in the small space. In addition, success is seen at younger ages when the target object is adjacent to the feature. These results favor an adaptive combination model of spatial reorientation over a 'module-plus-language' view.  相似文献   
132.
The current study explored the relationship between recall of a form of bullying, specifically childhood teasing, and later interpersonal functioning in a sample of 414 college students. It was predicted that memories of frequent teasing during childhood would be associated with fewer close friends, a more anxious attachment style in the context of romantic relationships, and lower social self-esteem in early adulthood. Although recalled-teasing was not associated with number of friends later in life, it was related to other interpersonal difficulties. Specifically, frequent teasing was associated with less comfort with intimacy and closeness, less comfort in trusting and depending on others, a greater degree of worry about being unloved or abandoned in relationships, and poorer social self-esteem. The relationship of these difficulties to specific domains of teasing was also explored.  相似文献   
133.
There has been a growing interest in using the Internet to access a variety of populations for prevention education and health care. It is not clear that this is viable for homeless and other marginalized populations. The purpose of this study was to describe Internet access and use among a sample of homeless and indigent drug users. A brief questionnaire was developed to assess computer ownership, use, email, and Internet access and use. Participants were recruited through a community-based human immunodeficiency virus (HIV) prevention program. 265 participants completed the questionnaire. While 55% had ever used a computer in their lifetime, only 25% had ever owned a computer, 24% had ever had their own email account, 33% had access to a working computer in the last 30 days, 10% had sent or received email in the last 30 days, and 19% had surfed or accessed information on the Internet in the last 30 days. Logistic regression predicting lifetime use of a computer showed predictive factors of having completed high school (Odds Ratio [OR] = 4.5; 95% Confidence Interval [CI] = 2.41, 8.38) and number of days used amphetamines in the last 30 days, per 5 days of use (OR = 1.64; 95% CI = 1.18, 2.27). Inversely related were age, per 5 years of age (OR = 0.78; 95% CI = 0.65, 0.93) and number of days used marijuana in the last 30 days, per 5 days of use (OR = 0.97; 95% CI = 0.76, 0.99). Very low access and usage suggest that Internet-based public health education models be reexamined for this population. The association with amphetamine use may indicate a facilitating effect of amphetamine by heightening awareness and increasing wakefulness.  相似文献   
134.
Recognizing limitations in classic cognitive moral development theory, several scholars have drawn from theories of identity to suggest that moral behavior results from both moral judgments and moral identity. The authors conducted 2 survey-based studies with more than 500 students and managers to test this argument. Results demonstrated that moral identity and moral judgments both independently influenced moral behavior. In addition, in situations in which social consensus regarding the moral behavior was not high, moral judgments and moral identity interacted to shape moral behavior. This interaction effect indicated that those who viewed themselves as moral individuals pursued the most extreme alternatives (e.g., never cheating, regularly cheating)--a finding that affirms the motivational power of a moral identity. The authors conclude by considering the implications of this research for both theory and practice.  相似文献   
135.
A 12-wk. study was conducted to contrast the effects of a longer and more frequent aerobic exercise protocol with a shorter and less frequent circuit strength-training protocol for improving U.S. Air Force physical fitness test scores of subjects who previously failed to achieve a passing point total. 83 men and women of the U.S. Air Force (M age = 32.7 yr.) participated in either the unsupervised standard conditioning program, which recommended approximately 60 min. of aerobic activity 4 to 5 days per week (n=26), or the supervised circuit strength-training program, which required approximately 25 min. of alternating strength and endurance exercises 3 days per week (n=57). Subjects were assessed on a 2400-m (1.5-mile) run, abdominal circumference, push-ups completed in 1 min., and abdominal crunches completed in 1 min. Dependent t tests with Bonferroni adjustment indicated that significant improvements were attained by the circuit strength-training group only on each of the aforementioned measures. Significantly more participants in the circuit strength-training group (26%) achieved a passing point total than in the standard conditioning group (19%) at Wk. 12 (chi1(2) =3.96, p = .05). Implications for enhancing physical fitness in poorly conditioned adults were discussed.  相似文献   
136.
Two experiments examine how collaboration influences visual search performance. Working with a partner or on their own, participants reported whether a target was present or absent in briefly presented search displays. We compared the search performance of individuals working together (collaborative pairs) with the pooled responses of the individuals working alone (nominal pairs). Collaborative pairs were less likely than nominal pairs to correctly detect a target and they were less likely to make false alarms. Signal detection analyses revealed that collaborative pairs were more sensitive to the presence of the target and had a more conservative response bias than the nominal pairs. This pattern was observed even when the presence of another individual was matched across pairs. The results are discussed in the context of task-sharing, social loafing and current theories of visual search.  相似文献   
137.
The authors present (a) an overview of the recent literature on social advocacy, (b) results of a deconstructive analysis of the philosophical and theoretical underpinnings of this movement, (c) a critical analysis of its role and function in the profession, and (d) a call to the profession. The deconstructive analysis revealed 2 major driving forces and 5 related trends; the critical analysis revealed 9 key areas of consideration. Implications and recommendations are presented.  相似文献   
138.
Contemporary social science paints a bleak picture of inner-city relational life. Indeed, the relationships of low-income, urban-residing Americans are represented as rife with distress, violence and family disruption. At present, no body of social scientific work systematically examines the factors that promote loving or selfless interactions among low-income, inner-city American individuals, families and communities. In an effort to fill that gap, this ethnographic study examined the motivations for altruism among a sample of adults (n = 40) who reside in an economically distressed housing community (i.e., housing project) in New York City. Content analyses of interviews indicated that participants attributed altruism to an interplay between 14 motives that were then ordered into four overarching categories of motives: (1) needs-centered motives, (2) norm-based motives deriving from religious/spiritual ideology, relationships and personal factors, (3) abstract motives (e.g., humanism), and (4) sociopolitical factors. The implications of these findings are discussed.  相似文献   
139.
Ramsey G  Bastian ML  van Schaik C 《The Behavioral and brain sciences》2007,30(4):393-407; discussion 407-32
Innovation is a key component of most definitions of culture and intelligence. Additionally, innovations may affect a species' ecology and evolution. Nonetheless, conceptual and empirical work on innovation has only recently begun. In particular, largely because the existing operational definition (first occurrence in a population) requires long-term studies of populations, there has been no systematic study of innovation in wild animals. To facilitate such study, we have produced a new definition of innovation: Innovation is the process that generates in an individual a novel learned behavior that is not simply a consequence of social learning or environmental induction. Using this definition, we propose a new operational approach for distinguishing innovations in the field. The operational criteria employ information from the following sources: (1) the behavior's geographic and local prevalence and individual frequency; (2) properties of the behavior, such as the social role of the behavior, the context in which the behavior is exhibited, and its similarity to other behaviors; (3) changes in the occurrence of the behavior over time; and (4) knowledge of spontaneous or experimentally induced behavior in captivity. These criteria do not require long-term studies at a single site, but information from multiple populations of a species will generally be needed. These criteria are systematized into a dichotomous key that can be used to assess whether a behavior observed in the field is likely to be an innovation.  相似文献   
140.
This paper combines three elements: a discussion of democratic values and the status of outsiders in Japanese political culture, the development of new measures to examine sensitive issues of nativism and foreigner perception in Japan, and an empirical exploration of the relationship between democratic values and antipathy toward outsiders. Two forms of democratic orientation were investigated in a sample of about 1,000 university students in Japan: a defensive version, which adheres to the formalistic requirements of democracy but is exclusionary and illiberal, and a universalist version that is liberal and tolerant. A defensive orientation is associated with greater chauvinism, a greater sense of threat emanating from foreigners, and a heightened anxiety about economic competition. A universalist orientation is associated with low perceived threat and low chauvinism, a lack of fear of economic competition, and a positive view of the cultural contributions of outsiders. Nativism may indeed be compatible with democratic values, but only with the defensive, exclusionary form. In short, the defensive form is democracy for xenophobes. Such an orientation is not unique to Japan, but is likely to be found in developing democracies as well as in advanced democracies that feel threatened.  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