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   1807篇
  免费   89篇
  2022年   10篇
  2021年   27篇
  2020年   30篇
  2019年   39篇
  2018年   65篇
  2017年   58篇
  2016年   64篇
  2015年   62篇
  2014年   52篇
  2013年   179篇
  2012年   87篇
  2011年   89篇
  2010年   52篇
  2009年   41篇
  2008年   84篇
  2007年   70篇
  2006年   68篇
  2005年   75篇
  2004年   52篇
  2003年   64篇
  2002年   48篇
  2001年   31篇
  2000年   23篇
  1999年   16篇
  1998年   22篇
  1997年   19篇
  1996年   19篇
  1995年   19篇
  1994年   14篇
  1993年   14篇
  1992年   14篇
  1991年   16篇
  1990年   22篇
  1989年   20篇
  1988年   11篇
  1987年   14篇
  1986年   10篇
  1985年   21篇
  1984年   24篇
  1983年   14篇
  1982年   21篇
  1981年   13篇
  1980年   27篇
  1979年   28篇
  1978年   21篇
  1977年   17篇
  1976年   17篇
  1975年   16篇
  1974年   18篇
  1973年   14篇
排序方式: 共有1896条查询结果,搜索用时 15 毫秒
801.
OBJECTIVE: Distress and low perceived social support were examined as indicators of psychosocial vulnerability in patients about to undergo heart surgery. Design: A total of 550 study patients underwent heart surgeries, including bypass grafting and valve procedures. Psychosocial interviews were conducted about five days before surgery, and biomedical data were obtained from hospital records. MAIN OUTCOME MEASURES: Sociodemographic, personality, religious, and biomedical factors were evaluated as predictors of psychosocial vulnerability, and all five sets of variables were evaluated as contributors to hospital length of stay (LOS). RESULTS: Patients scoring higher on one or more indicator of presurgical psychosocial vulnerability were younger, more likely to be female, less likely to be married, less well educated, lower in dispositional optimism, higher in trait anger, and lower in religiousness. Older age, depression, low support, and low trait anger each showed an independent, prospective association with greater LOS, and several other predictors had prospective relationships with LOS that were statistically mediated by depression or perceived support. CONCLUSION: Evidence that multiple psychosocial factors may influence adaptation to heart surgery has implications for understanding and ameliorating presurgical distress and for improving postsurgical recovery.  相似文献   
802.
It is well known that a gender difference in physical aggression emerges by the preschool years. We tested the hypothesis that the gender difference is partly due to changing tactics in peer interaction. Observations of girls’ and boys’ social initiatives and reactions to opportunities for conflict were made, using the Peer Interaction Coding System (PICS) in four independent samples of children between 9 and 36 months of age, which were aggregated to form a summary data set (N= 323), divided into two age bands (below or above 24 months of age). Linear mixed‐model analyses revealed significant age by gender interactions in the use of bodily force in response to peers’ initiatives and in the tendency to use bodily force at later stages of conflicts with peers. The gender difference in use of force was not explained by differences in the use of verbal tactics. These cross‐sectional findings suggest that girls are initially more likely than boys to use reactive aggression, but then desist, whereas boys increase their use of force to defend their territory and possessions. The difference between older and younger girls likely reflects girls’ abilities to regulate their behaviour in response to social challenges and the fact that girls are explicitly socialized to yield to peers’ demands.  相似文献   
803.
804.
805.
Use of electronic games by young children and fundamental movement skills?   总被引:1,自引:0,他引:1  
This study investigated associations between pre-school children's time spent playing electronic games and their fundamental movement skills. In 2009, 53 children had physical activity (Actigraph accelerometer counts per minute), parent proxy-report of child's time in interactive and non-interactive electronic games (min./week), and movement skill (Test of Gross Motor Development-2) assessed. Hierarchical linear regression, adjusting for age (range = 3-6 years), sex (Step 1), and physical activity (cpm; M=687, SD=175.42; Step 2), examined the relationship between time in (a) non-interactive and (b) interactive electronic games and locomotor and object control skill. More than half (59%, n=31) of the children were female. Adjusted time in interactive game use was associated with object control but not locomotor skill. Adjusted time in non-interactive game use had no association with object control or locomotor skill. Greater time spent playing interactive electronic games is associated with higher object control skill proficiency in these young children. Longitudinal and experimental research is required to determine if playing these games improves object control skills or if children with greater object control skill proficiency prefer and play these games.  相似文献   
806.
Importing Logics     
The novel notion of importing logics is introduced, subsuming as special cases several kinds of asymmetric combination mechanisms, like temporalization [8, 9], modalization [7] and exogenous enrichment [13, 5, 12, 4, 1]. The graph-theoretic approach proposed in [15] is used, but formulas are identified with irreducible paths in the signature multi-graph instead of equivalence classes of such paths, facilitating proofs involving inductions on formulas. Importing is proved to be strongly conservative. Conservative results follow as corollaries for temporalization, modalization and exogenous enrichment.  相似文献   
807.
The first aim of this study was to estimate the prevalence of anxiety and DSM-related anxiety symptom-clusters among adolescents (13-19 years of age) in middle Norway. A second aim was to examine the developmental trajectories of anxiety symptoms for boys and girls during adolescence. In a cross-sectional study, 1,802 students in junior high schools and high schools in the Mid-Norway Health Region filled out a questionnaire (a response-rate of 77%) including the SCARED self-report form (Birmaher et al., 1997) during one school hour. In line with findings of previous studies, girls reported higher anxiety-levels than did boys. A large gender-specific increase in anxiety in 14-15-year-old girls was also found. Apart from this age-specific effect, the results indicated a general reduction in anxiety during adolescence for all symptom groups except generalized anxiety and school phobia. The high anxiety levels in girls aged 13 to 14 years implicate a need for caution by clinicians because such high anxiety levels may be mistaken for the existence of an anxiety disorder. The rapid increase in anxiety symptoms among girls in early adolescence may reflect a heightened sensitivity in this age group, and may have implications for when to implement secondary prevention programs.  相似文献   
808.
Acute stress disorder (ASD) was included as a diagnosis to the 4th edition of the Diagnostic and Statistical Manual (American Psychiatric Association, 1994) as a way of describing pathological reactions in the first month following a trauma. Since that time, ASD has been the focus of some controversy, particularly regarding the theoretical basis and practical utility of the disorder. Despite this controversy, ASD has demonstrated usefulness in identifying individuals experiencing a high level of distress in the acute aftermath of a trauma as well as those at risk for developing posttraumatic stress disorder (PTSD). This paper reviews the clinical application of ASD, the current controversy surrounding its conceptual basis, and then discusses the dilemmas regarding this diagnosis that might occur in clinical practice. A review of the randomized control trial treatment outcome literature for ASD is also included in an effort to assist clinicians selecting interventions for clients recently exposed to traumatic events. Throughout this paper, the relationship between research and applied clinical practice is highlighted.  相似文献   
809.
In line with self-determination theory (SDT: Deci & Ryan, 1985, 2002) the satisfaction of the basic psychological needs for autonomy, competence, and relatedness has been identified as an important predictor of behavior and optimal functioning in various contexts including exercise. The lack of a valid and reliable instrument to assess the extent to which these needs are fulfilled among Portuguese exercise participants limits the evaluation of causal links proposed by SDT in the Portuguese exercise context. The aim of the present study was to translate into Portuguese and validate the Basic Psychological Needs in Exercise Scale (BPNES: Vlachopoulos & Michailidou, 2006). Using data from 522 exercise participants the findings provided evidence of strong internal consistency of the translated BPNES subscales while confirmatory factor analysis supported a good fit of the correlated 3-factor model to the data. The present findings support the use of the translated into Portuguese BPNES to assess the extent of basic psychological need fulfilment among Portuguese exercise participants.  相似文献   
810.
In the literature, politeness has been researched within many disciplines. Although Brown and Levinson's theory of politeness (1978, 1987) is often cited, it is primarily a linguistic theory and has been criticized for its lack of generalizability to all cultures. Consequently, there is a need for a more comprehensive approach to understand and explain politeness. We suggest applying a social signal framework that considers politeness as a communicative state. By doing so, we aim to unify and explain politeness and its corresponding research and identify further research needed in this area.  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