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231.
I argue that there is natural relationist interpretation of Newtonian and relativistic non-quantum physics. Although relationist, this interpretation does not fall prey to the traditional objections based on the existence of inertial effects.  相似文献   
232.
Five Minute Speech Sample Expressed Emotion (FMSS-EE) was examined in families of youth with depressive disorders, nondepressed youth with attention deficit/hyperactivity disorder (ADHD), and community controls screened for the absence of depression and ADHD. Consistent with the hypothesis that FMSS-EE shows some specificity as a risk factor for depression, rates of critical EE were significantly higher among mothers of youth with depression as compared to mothers of nondepressed youth with ADHD, or mothers of controls. When both mothers' and fathers' scores were used to generate family EE ratings, rates of overall EE and critical EE were significantly higher for the depressed group than the control group, but the nondepressed ADHD group did not differ significantly from the other groups. Results support the hypothesis that critical EE in mothers shows some specificity as a risk factor or correlate of depression in youth.  相似文献   
233.
This investigation examined the moderating influences of perceived control (i. e., personal control and job self‐efficacy) on relationships between perceptions of organizational politics and organizational commitment, job satisfaction, intention to turnover, and job stress. Although results failed to support predictions concerning the interaction of perceptions of organizational politics and personal control, some support was found for predictions concerning the interactive influence of perceptions of organizational politics and job self‐efficacy on outcomes. Data from 189 hotel managers supported the hypothesized interactive effects of perceptions of organizational politics and job self‐efficacy for the outcomes of organizational commitment and job satisfaction. These results suggest that job self‐efficacy exacerbates the relationship between perceived politics and certain dysfunctional attitudes.  相似文献   
234.
A variable-selection heuristic for K-means clustering   总被引:4,自引:0,他引:4  
One of the most vexing problems in cluster analysis is the selection and/or weighting of variables in order to include those that truly define cluster structure, while eliminating those that might mask such structure. This paper presents a variable-selection heuristic for nonhierarchical (K-means) cluster analysis based on the adjusted Rand index for measuring cluster recovery. The heuristic was subjected to Monte Carlo testing across more than 2200 datasets with known cluster structure. The results indicate the heuristic is extremely effective at eliminating masking variables. A cluster analysis of real-world financial services data revealed that using the variable-selection heuristic prior to the K-means algorithm resulted in greater cluster stability.  相似文献   
235.
This research examined whether peer relationships amongst ethnic minority status children reflect the social groups to which children belong and the degree to which they identify with these groups. A longitudinal study was conducted to investigate the influence of group identities (i.e., ethnic and national) on children's perceived peer acceptance and preference for same‐ethnic friendships. Measures of ethnic and English identification, perceived peer acceptance, and friendship choice were administered to 207 south‐Asian English children, aged between 5 and 11, at two time points 6 months apart. In line with predictions, longitudinal analysis showed that bicultural identification (i.e., higher ethnic and English identity) was related to higher perceived peer acceptance and less preference for same‐ethnic friendships. Importantly, as hypothesized, this finding was limited to the older children with more advanced social‐cognitive abilities. The results suggest that older children who adopted a bicultural identity were able to strategically ‘flag’ their multiple group identities, within their multicultural peer groups, to obtain acceptance amongst the maximum number of peers and show less preference for same‐ethnic friendships. This study extends previous peer relations research, which has typically focused on individual social deficits or classroom norms, by showing that group identities influence peer relationships amongst ethnic minority status children.  相似文献   
236.
237.
A helpful component for comprehensive residential services for developmentally disabled persons is volunteer assistance. This investigation involved the evaluation of a program developed to increase the amount of volunteer assistance provided to a public residential facility. The program consisted of three types of related procedures: systematic volunteer recruitment steps, specific volunteer activities at the facility, and consequence/recognition for the volunteer assistance. The program was successively implemented to involve students as volunteers from two local universities, and resulted in an increase in new students volunteering from both universities. Additionally, the frequency with which the students volunteered at the residential facility increased substantially from both universities relative to control periods during which the volunteer program was not in effect. Results are discussed in terms of the benefits of volunteers and continued research to increase involvement of other prospective groups of volunteers.  相似文献   
238.
It is generally believed that correlations and standard deviations measured within an explicitly selected group must be smaller than those within an applicant population. A small data set is used to show that this is not always true, and that both validity and reliability estimates within a selected group can exceed those within the applicant population. The increase in correlation within the explicitly selected group is tied to an increase in standard deviation of the predictor in the selected group. This conclusion extends Levin's (1972) result for the case of incidental selection, selection on an unmeasured third variable. If possible, theoretical derivations should not be limited to the case where the predictor standard deviation in the applicant population exceeds that in the selected group. When such a situation occurs in observed data, it cannot be immediately dismissed as an artifact.The author would like to thank Mark L. Davison and other reviewers for their comments on earlier drafts of the paper. An anonymous reviewer provided a better example than the original one, resulting in a more general conclusion.This work was supported in part by a Dissertation Fellowship from the University of Minnesota.  相似文献   
239.
The factor structure of the Stunkard-Messick Eating Questionnaire (SMEQ) differs from that of the Dutch Eating Behavior Questionnaire (DEBQ). Using students and members of a weight watchers club, we factor-analyzed responses to the SMEQ and produced a solution which was different from that obtained by Stunkard and Messick, but which had some similarities to the factor structure of the DEBQ. “External” taste items and “internal” hunger items loaded on the same factor, a finding inconsistent with externality theory but consistent with the common sense notion of appetite strength. Although our finding suggests factor instability of the SMEQ, the stability of the DEBQ appears to be the consequence of a restricted range of DEBQ items compared with SMEQ items. Financial support for this research was given by Lilly Industries.  相似文献   
240.
The first part of the article considers what proponents of the most familiar egalitarian moral theories would say about age-group inequality. I claim that these theories have intuitively objectionable consequences. The second part explains and criticizes a theory of justice formulated specifically for age-groups: Norman Daniels' prudential lifespan account. In the third part I explain two views that seem to me to give a better account of justice between the young and the old.  相似文献   
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