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   699篇
  免费   60篇
  2022年   7篇
  2021年   18篇
  2020年   14篇
  2019年   21篇
  2018年   35篇
  2017年   33篇
  2016年   38篇
  2015年   29篇
  2014年   30篇
  2013年   68篇
  2012年   33篇
  2011年   34篇
  2010年   17篇
  2009年   17篇
  2008年   30篇
  2007年   19篇
  2006年   18篇
  2005年   21篇
  2004年   12篇
  2003年   27篇
  2002年   21篇
  2001年   10篇
  2000年   14篇
  1999年   7篇
  1998年   11篇
  1997年   8篇
  1996年   11篇
  1995年   6篇
  1994年   5篇
  1993年   6篇
  1992年   6篇
  1991年   7篇
  1990年   9篇
  1989年   12篇
  1988年   4篇
  1987年   4篇
  1986年   4篇
  1985年   7篇
  1984年   4篇
  1983年   9篇
  1982年   8篇
  1981年   4篇
  1979年   7篇
  1978年   8篇
  1977年   8篇
  1976年   4篇
  1974年   4篇
  1973年   3篇
  1970年   4篇
  1969年   4篇
排序方式: 共有759条查询结果,搜索用时 15 毫秒
111.
We introduce and extend the classical regression framework for conducting mediation analysis from the fit of only one model. Using the essential mediation components (EMCs) allows us to estimate causal mediation effects and their analytical variance. This single-equation approach reduces computation time and permits the use of a rich suite of regression tools that are not easily implemented on a system of three equations. Additionally, we extend this framework to non-nested mediation systems, provide a joint measure of mediation for complex mediation hypotheses, propose new visualizations for mediation effects, and explain why estimates of the total effect may differ depending on the approach used. Using data from social science studies, we also provide extensive illustrations of the usefulness of this framework and its advantages over traditional approaches to mediation analysis. The example data are freely available for download online and we include the R code necessary to reproduce our results.  相似文献   
112.
As interviewees typically say less when an interpreter is present, we examined whether this was caused by interpreters not interpreting everything interviewees says or by interviewees providing less information. We further examined (a) the effect of a model drawing on providing information and (b) the diagnostic value of total details and the proportion of complications as cues to deceit. Hispanic, Russian, and South Korean participants were interviewed by native interviewers or by a British interviewer through an interpreter. Truth tellers discussed a trip they had made; liars fabricated a story. Participants received no instruction (condition 1) or were instructed to sketch while narrating without (condition 2) or with (condition 3) being given examples of detailed sketches. Interviewees said less when an interpreter was present because they provided less information. Truth tellers gave more details and, particularly, obtained a higher proportion of complications than liars. The sketching manipulation had no effect.  相似文献   
113.
Social network analysis has become a prominent tool to study animal social life, and there is an increasing need to develop new systems to collect social information automatically, systematically, and reliably. Here we explore the use of a freely accessible Automated Learning Device for Monkeys (ALDM) to collect such social information on a group of 22 captive baboons (Papio papio). We compared the social network obtained from the co-presence of the baboons in ten ALDM testing booths to the social network obtained through standard behavioral observation techniques. The results show that the co-presence network accurately reflects the social organization of the group, and also indicate under which conditions the co-presence network is most informative. In particular, the best correlation between the two networks was obtained with a minimum of 40 days of computer records and for individuals with at least 500 records per day. We also show through random permutation tests that the observed correlations go beyond what would be observed by simple synchronous activity, to reflect a preferential choice of closely located testing booths. The use of automatized cognitive testing therefore presents a new way of obtaining a large and regular amount of social information that is necessary to develop social network analysis. It also opens the possibility of studying dynamic changes in network structure with time and in relation to the cognitive performance of individuals.  相似文献   
114.
Using a classical eyeblink conditioning paradigm, we have previously shown that the rate of acquisition of a conditioned response may be manipulated by engaging subjects in background tasks of varying complexity concurrent to conditioning. To further examine the influence of the background environment on conditioning, a picture set designed to elicit emotional responses, the International Affective Picture System (IAPS), was presented to subjects during classical eyeblink conditioning. The results suggest that eyeblink conditioning does appear to be sensitive to contextual manipulations of arousal. Pictures rated as very arousing were found to engage subjects enough to enhance learning, although not to the point that autonomic functions were significantly altered between picture groups. We suggest that group differences in learning may be a result of either novelty of, or vigilance to, interesting pictures rather than as a direct result of physiological arousal.  相似文献   
115.
Mental health problems are underrecognized in medical settings, leading to inadequate treatment. The present paper describes the development of the Health Dynamics Inventory (HDI), a brief, self-report questionnaire developed to evaluate mental health functioning. The HDI was written to evaluate the three aspects of mental disorders as described in the Diagnostic and Statistical Manual of Mental Disorders (DSM): (1) the experience of emotional or behavioral symptoms; (2) emotional distress; and (3) psychosocial impairment. This study evaluated the psychometric properties and construct validity of its items, scales, and subscales. Results indicated that the items distinguish patients from nonpatients, that the instrument's scales and subscales are reliable, and that the scales and subscales discriminates between persons with mental health concerns or diagnosable problems and those without such concerns or problems. The utility of the instrument for screening mental health problems in primary care settings is discussed.  相似文献   
116.
This study examined the relative importance of self‐esteem, family cohesion, and support from friends in predicting depressed mood and anxiety in Japanese and American college students. Contrary to expectations, self‐esteem was the strongest predictor of emotional distress in both groups of students. Nevertheless, consistent with predictions derived from Markus and Kitayama's theory of self‐construals, family cohesion accounted for a significantly larger percentage of the variance in predicting emotional distress in Japan than in the United States. In both countries, the relations between support from friends and the measures of emotional distress were entirely mediated by self‐esteem. However, among Japanese students, family cohesion accounted for additional significant variance in predicting the measures of emotional distress, even after controlling for self‐esteem.  相似文献   
117.
Analogical reasoning is considered the hallmark of human reasoning, but some studies have demonstrated that language- and symbol-trained chimpanzees can also reason analogically. Despite the potential adaptive value of this ability, evidence from other studies strongly suggests that other nonhuman primates do not have this capacity for analogical reasoning. In our three experiments, 6 of 29 baboons acquired the ability to perform a relational matching-to-sample (RMTS) task in which pairs of shapes composed relational displays. Five of these 6 monkeys then transferred this ability to RMTS tasks using novel exemplars of identity (elements in a pair are the same) and nonidentity (elements in a pair are different) relations. This transfer occurred even on trials in which the incorrect pair shared an element with the sample pair with which it was being compared. The baboons retained this ability 12 months later. The findings from our study of symbol-naive monkeys indicate that although language and symbol training facilitate conceptual thinking in nonhuman primates, such training is not a prerequisite for analogical reasoning.  相似文献   
118.
Perceivers generally show a poor ability to detect changes, a condition referred to as “Change Blindness” (CB). They are, in addition, “blind to their own blindness”. A common explanation of this “Change Blindness Blindness” (CBB) is that it derives from an inadequate, “photographical” folk-theory about perception. This explanation, however, does not account for intra-individual variations of CBB across trials. Our study aims to explore an alternative theory, according to which participants base their self-evaluations on two activity-dependent cues, namely search time and perceived success in prior trials. These cues were found to influence self-evaluation in two orthogonal ways: success-feedback influenced self-evaluation in a global, contextual way, presumably by recalibrating the norm of adequacy for the task. Search time influenced it in a local way, predicting the success of a given trial from its duration.  相似文献   
119.
We present the first steps in the validation of an observational tool for father-mother-infant interactions: the FAAS (Family Alliance Assessment Scales). Family-level variables are acknowledged as unique contributors to the understanding of the socio-affective development of the child, yet producing reliable assessments of family-level interactions poses a methodological challenge. There is, therefore, a clear need for a validated and clinically relevant tool. This validation study has been carried out on three samples: one non-referred sample, of families taking part in a study on the transition to parenthood (normative sample; n = 30), one referred for medically assisted procreation (infertility sample; n = 30) and one referred for a psychiatric condition in one parent (clinical sample; n = 15). Results show that the FAAS scales have (1) good inter-rater reliability and (2) good validity, as assessed through known-group validity by comparing the three samples and through concurrent validity by checking family interactions against parents’ self-reported marital satisfaction.  相似文献   
120.
There are few studies on the development of anxiety and depression in orthopaedics and trauma (O&T) inpatients. We designed a cross-sectional study aimed at comparing the prevalence of depression and anxiety in 100 O&T inpatients and 100 clinical inpatients in the same hospital. O&T patients were divided into subgroups: trauma and non-trauma (arthroplasty, tumour, and infection sub grouping). We measured anxiety and depression by the Hospital Anxiety and Depression Scale and co-morbidities by the Charlson age-adjusted comorbidity index (CCI). For the trauma subgroup, AO/OTA fracture classification and Gustillo and Anderson grade of open fractures classification was applied. The prevalence of anxiety and depression was 35% and 28%, respectively for the clinical sample, and 44% and 33% for the O&T sample. Compared with the clinical sample, anxiety scores were higher in the O&T sample (p = .047), and in arthroplasty (p = .020) and trauma subgroups (p = .031). In the O&T sample, high CCI scores were associated with high anxiety scores (p = .033).  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