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   2685篇
  免费   156篇
  国内免费   2篇
  2024年   5篇
  2023年   34篇
  2022年   48篇
  2021年   67篇
  2020年   75篇
  2019年   104篇
  2018年   132篇
  2017年   142篇
  2016年   100篇
  2015年   83篇
  2014年   95篇
  2013年   327篇
  2012年   196篇
  2011年   202篇
  2010年   131篇
  2009年   81篇
  2008年   178篇
  2007年   122篇
  2006年   134篇
  2005年   87篇
  2004年   66篇
  2003年   61篇
  2002年   56篇
  2001年   31篇
  2000年   32篇
  1999年   20篇
  1998年   14篇
  1997年   13篇
  1996年   9篇
  1995年   11篇
  1994年   13篇
  1993年   6篇
  1992年   14篇
  1991年   11篇
  1990年   15篇
  1989年   12篇
  1988年   8篇
  1987年   12篇
  1986年   9篇
  1985年   9篇
  1983年   4篇
  1982年   6篇
  1981年   8篇
  1980年   5篇
  1979年   7篇
  1975年   6篇
  1974年   5篇
  1972年   5篇
  1969年   3篇
  1963年   3篇
排序方式: 共有2843条查询结果,搜索用时 15 毫秒
991.
The ability to assess genetic ties is critical to defining one's own family and, in a broader context, to understanding relationships in groups of strangers. To recognize younger siblings as such, human firstborns can rely on the perinatal association of the mother with her new baby. Later-borns, who cannot rely on such an association, will by necessity actuate alternate strategies, such as recognition of facial clues set aside by firstborns. The effects of such differential early experiences deserve consideration; the development of matching abilities may be used throughout an individual's lifetime to detect other kinship types outside the family. In simple cognitive tasks based on matching face pictures, later-borns surpassed firstborns in detecting kinship among strangers; this pattern was found in populations of different ages and in two countries. This birth-order effect contrasts with the traditional cognitive advantage of firstborns. Inclusive fitness theory explains how early life history promotes specific strategies that can, in turn, permanently enhance human performance in certain domains.  相似文献   
992.
Most theories of persuasion predict that limited ability and motivation to think about communications should increase the impact of source credibility on persuasion. Furthermore, this effect is assumed to occur, regardless of whether or not the recipients have prior attitudes. In this study, the effects of source credibility, ability, and motivation (knowledge, message repetition, relevance) on persuasion were examined meta-analytically across both attitude formation and change conditions. Findings revealed that the Source Credibility × Ability/Motivation interaction emerged only when participants lacked prior attitudes and were unable to form a new attitude based on the message content. In such settings, the effects of source credibility decayed rapidly. The implications of these findings for applied communication campaigns are discussed.  相似文献   
993.
This qualitative study is an exploration of 32 urban high school students' narratives about the connection between school, work, and societal expectations of their future success related to their racial and ethnic background. The sample varied along 2 contextual dimensions: participation in a psychoeducational intervention (Tools for Tomorrow) and developmental status (i.e., half the sample were 9th-grade students and the other half were 12th-grade students). Using consensual qualitative research, the narratives revealed 3 major domains: future orientation; students' perceptions of society's expectations based on race and ethnicity; and students' perception of the role of their race and ethnicity in future success. Results reveal that the majority of students endorse a connection between school and work, believe that society holds low expectations for them based on their racial and ethnic background, and cannot predict their future success based on their background.  相似文献   
994.
The current study aims to investigate the factorial validity of a widely used psychopathological rating scale, the Symptom Check List-90-R (SCL-90-R), in a group of patients suffering from gastrointestinal disorders, and to determine the specific psychopathological profiles that characterize the individual patient subgroups. Patients suffering from either irritable bowel syndrome, ulcerative colitis, non-erosive reflux disease or erosive reflux disease completed the SCL-90-R at a tertiary care gastroenterology department. Seven factors were identified, with one major distress factor and six minor factors. Comparison of the gastrointestinal disorder subgroups indicated that irritable bowel syndrome patients exhibited significantly more psychological distress compared to the other groups, and that gastrointestinal patients as a group, compared to healthy controls, were characterized by high levels of irritable depression and somatization. In planning further studies we encourage the use of factors identified in our study. The treatment of substantial irritable depression can be an important factor in improving quality of life in patients suffering from gastrointestinal disorders.  相似文献   
995.
A course in professional ethics for civil engineers was taught for the first time in Spain during the academic year 2007/08. In this paper a survey on the satisfaction and expectation of the course is presented. Surprisingly the students sought moral and ethical principles for their own ordinary lives as well as for their profession. Students were concerned about the law, but in their actions they were more concerned with their conscience, aware that it can be separate from the law.  相似文献   
996.
Expanding our knowledge on parenting practices of immigrant families is crucial for designing culturally sensitive parenting intervention programs in countries with high immigration rates. We investigated differences in patterns of parenting between second-generation immigrant and native families with young children. Authoritarian and authoritative control and sensitivity of second-generation Turkish immigrant mothers of 2-year-old children (n = 70) and native Dutch mothers (n = 70) were observed in the home and in the laboratory. Controlling for maternal age and education, Turkish immigrant mothers were less supportive, gave less clear instructions to their children, were more intrusive and were less authoritative in their control strategies than native Dutch mothers. No differences were found in authoritarian control. In both ethnic groups supportive presence, clarity of instruction, authoritative control, and low intrusiveness loaded on one factor. No differences between ethnic groups were found in gender-differentiated parenting. Maternal emotional connectedness to the Turkish culture was associated with less authoritative control, whereas more use of the Turkish language was related to more sensitivity. Even though mean level differences in parenting behaviors still exist between second-generation Turkish immigrant and native Dutch mothers, the patterns of associations between parenting behaviors were comparable for both groups. This suggests that existing parenting interventions for native families may be applicable to second-generation Turkish immigrants as well.  相似文献   
997.
Animal innovations have far-reaching ecological and evolutionary consequences. The occurrence and persistence of an innovation require several processes, including exploration, social and asocial learning, and low neophobia. In addition, the identity of the innovator may determine how these new behaviours are socially transmitted. Taking into account inter-individual and age differences, we investigated three correlates of animal innovation: object exploration, neophobia level and novel problem-solving ability in an opportunistic generalist raptor, the Chimango Caracara (Milvago chimango). Eighteen individuals (7 adults and 11 juveniles) were caught during the non-breeding period and housed in individual cages in outdoor aviaries. Each bird was given three tests: exploration, neophobia and problem-solving. Individuals differed in their response to novel situations both within and between age groups. Most of the juveniles were more explorative and had a lower neophobic response to a strange object than adult birds, but both age groups were able to solve a novel problem when given a food reward. In juveniles, neophobia level and problem-solving performance were inversely related; however, we found no relationship between these behaviours in adults. Exploration did not correlate with neophobia or problem-solving ability for either age group. This research is one of the few studies exploring the inter-individual and age differences in behavioural innovation and their correlates in a bird of prey. The explorative tendency, low neophobia and ability to innovate showed by M. chimango may be advantageous for this generalist and opportunistic raptor and might be some of the factors underlying its ecological success.  相似文献   
998.
A considerable number of studies have recently used event-related potentials (ERPs) to investigate the mechanisms underlying error processing. Nevertheless, how these mechanisms are associated with behavioral adjustments following errors remains unclear. In the present study, we investigated how posterror slowing is linked to outcome expectations and error feedback. We used an adaptive four-choice reaction time task to manipulate outcome expectancy. Behaviorally, the results show posterror slowing when errors are unexpected and postcorrect slowing when correct responses are unexpected, indicating that outcome expectancy is crucial for posterror slowing. ERP analyses revealed that the error-related negativity and the feedback-related negativity were not correlated with the behavioral reaction time pattern, whereas the P3 was. The results support the hypothesis that posterror slowing is caused by attentional orienting to unexpected events.  相似文献   
999.
1000.
A participatory research action was undertaken in the two largest shelters established after the earthquakes in El Salvador (2001). One hundred fifteen semi‐structured interviews were carried out among refugees, which later formed the basis for a self‐managed community plan. Comparisons between the two shelters—which differed primarily in whether the grouping of tents was made to reflect the community of origin of the survivors (shelter Santa Gertrudis) or not (shelter El Cafetalón)—showed that refugees in Santa Gertrudis participated more often in community activities, and had more positive emotional memories, fewer feelings of having been humiliated and less emotional discomfort than refugees in El Cafetalón. The results suggest that forms of organisation and management which consider elements of dignity, participation and respect for the capacity of the victims to control their own lives are relevant factors for effective individual and community coping after a catastrophe. Copyright © 2005 John Wiley & Sons, Ltd.  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