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31.
A total of 229 late adolescents (a large majority 15 to 19 years of age) completed a questionnaire that assesses a broad range of videogame-relevant experiences, preferences, and attitudes. Videogame playing was found to be a more popular, and a more highly regarded, activity among males than females. Gender differences were also found in participants' ratings of their motivations for playing videogames, their evaluations of particular characteristics of videogames, and their selection of their “most favorite” videogame. The differences between frequent and infrequent videogame players appeared to be limited to differences in the extent to which videogame playing is pursued and evaluated as a positive leisure activity, rather than reflecting broad differences in interest or personality. Some relations were found between participants' self-reported personality characteristics (i.e., self-esteem, empathy, conscientiousness, and introversion) and their attitudes toward videogames.  相似文献   
32.
In this paper I wish to show that we can give a statement of a restricted form of Gleason's Theorem that is classically equivalent to the standard formulation, but that avoids the counterexample that Hellman gives in Gleason's Theorem is not Constructively Provable.  相似文献   
33.
Functional neuroimaging has been used to investigate neural substrates of mnemonic processes, and cerebral blood flow (CBF) measures have been sensitive to activation with memory tasks. Studies of memory with two-dimensional133Xenon clearance techniques found that word and face recognition tasks produced contralateral CBF changes in mid-temporal cortical regions. This study replicated the activation paradigm, expanding to the three-dimensional resolution of positron emission tomography (PET). Word and face recognition, and a control baseline task were administered to 19 healthy right-handed volunteers (11 men, 8 women) during successive 10 min PET15O-water measures of CBF. Quantitative CBF rates were calculated with the arterial input function and the equilibrium model. Redistributions of blood flow were compared across tasks using both absolute and relative (region/whole brain) CBF.Replicating the133Xenon clearance findings, CBF was “appropriately” lateralized during task performance (left–right for words > left–right for faces) in the mid-temporal region. Contrary to predictions, the recognition tasks did not activate expected mesolimbic or prefrontal areas. The task-induced CBF changes also correlated with performance. Bilateral CBF in mid-temporal and parahippocampal gyrus regions of interest correlated with the ability to correctly identify word targets (sensitivity). Left-lateralized CBF in the amygdala and hippocampus correlated with better word sensitivity as well as specificity (ability to correctly reject foils). Complementally, right-lateralized CBF in the parahippocampal gyrus correlated with better face specificity performance. In addition, left-lateralized CBF in the amygdala and right-lateralized CBF in the parahippocampal gyrus and hippocampus correlated with “mental effort” indices (task performance relative to basal ability) for word and face memory tasks, respectively. Thus, whereas this recognition task showed the expected lateralized increase in the mid-temporal region and not in frontal and limbic areas, lateralized activation in some of these areas was associated with better performance. Exploratory analyses on other regions showed lateralized changes in one additional temporal region, the occipital-temporal, and several limbic regions.  相似文献   
34.
Helen E. Longino 《Synthese》1995,104(3):383-397
Traits like simplicity and explanatory power have traditionally been treated as values internal to the sciences, constitutive rather than contextual. As such they are cognitive virtues. This essay contrasts a traditional set of such virtues with a set of alternative virtues drawn from feminist writings about the sciences. In certain theoretical contexts, the only reasons for preferring a traditional or an alternative virtue are socio-political. This undermines the notion that the traditional virtues can be considered purely cognitive.I am grateful to participants in the Indiana University Workshop on Social Values in the Context of Justification for their comments on an earlier, spoken, version of this paper.  相似文献   
35.
Previous research indicates that vasopressin-containing (LE) rats are capable of adapting to the stress of food restriction, whereas vasopressin-deficient (DI) rats cannot adapt to this stressor. It has been postulated that abnormalities in glucose metabolism may be one of the factors leading to the demise of food-restricted DI rats. The present study was conducted to determine if taste preferences are altered in DI animals and if the presentation of exogenous glucose, in the form of sucrose solutions, can ameliorate the effects of the stress of food restriction. Four different concentrations of sucrose solutions were presented to LE and DI rats under the food-restricted condition. In both strains, an 8% sucrose solution was preferred over 0%, 16%, and 32% concentrations, with DI rats consuming more of this concentration than LE rats. Thus, when DI rats had the opportunity of maintaining glucose homeostasis by exogenous supplements, they maintained body weight, displayed no stomach pathology, and survived.  相似文献   
36.
Relatives (N=121) of adult schizophrenia patients were interviewed to investigate predictors of their level of psychological distress and of rejecting attitudes toward the sufferer. The relatives' total stress, particularly that associated with poor communication skills in the sufferer, predicted several measures of their psychological distress, and the same variables plus turbulence of sufferer behavior (i.e., violence and disruptiveness) predicted rejection of the sufferer by the relative. In each case, adequacy of family support moderated the influence of the stressors, although this effect was more marked for distress outcomes than for rejection. The results have important implications for the sorts of professional and peer support which relatives may need to encourage their performance of this potentially burdensome role. In addition, the results fit a classic stress management model and provide a feasible alternative to the Expressed Emotion Model of the relationship between relatives' rejection and patients' illness severity.  相似文献   
37.
A contrived play group procedure was utilized to examine the behavioral and social-cognitive correlates of reactive aggression, proactive aggression, and victimization via peers. Eleven play groups, each of which consisted of six familiar African-American 8-year-old boys, met for 45-min sessions on five consecutive days. Social-cognitive interviews were conducted following the second and fourth sessions. Play group interactions were videotaped and examined by trained observers. High rates of proactive aggression were associated with positive outcome expectancies for aggression/assertion, frequent displays of assertive social behavior, and low rates of submissive behavior. Reactive aggression was associated with hostile attributional tendencies and frequent victimization by peers. Victimization was associated with submissive behavior, hostile attributional bias, reactive aggression, and negative outcome expectations for aggression/assertion. These results demonstrate that there is a theoretically coherent and empirically distinct set of correlates associated with each of the examined aggression subtypes, and with victimization by peers.  相似文献   
38.
The health belief model was evaluated for its ability to predict perceived and actual dietary quality. The assessment relied upon data collected from 1,502 respondents by the US. Department of Agriculture in its 1991 Continuing Survey of Food Intakes by Individuals and the Diet and Health Knowledge Survey. The health belief model provided good prediction of perceived dietary quality, but provided moderate to weak prediction of 7 measures of actual dietary quality that were calculated from food intake records. Implications are suggested for using the health belief model to understand the determinants of dietary quality.  相似文献   
39.
This paper discusses the notions of failure and mistakes in family therapy, arguing that there are insufficient accounts in the literature which reflect the untidiness and disorder of everyday practice. The idea of dominant and subjugated stories is invoked to map the influence of notions of failure upon family therapy practice. It is argued that our practice would benefit if more accounts of our work routinely included stories of failure, mistakes and regret.  相似文献   
40.
This paper tests a meta-model of youthful marijuana use on students in Grades 11, 12 and 13. Although the specific models for each grade varied in detail, all followed a meta-model making the following assumptions: (1) that use or nonuse of marijuana depends primarily on attitude towards use; (2) that attitude largely reflects the perceived functional and dysfunctional consequences of use; and (3) that what people perceive as functional or dysfunctional depends on relevant personality characteristics. All three models showed satisfactory goodness-of-fit in terms of nonsignificant overidentification tests (minimum P > 0.25) and small discrepancies between observed correlations and the corresponding theoretically implied correlations. A notable feature of the Grade 13 data in contrast to those for Grade 12 and previously reported findings was the seeming unimportance of the perceived value of marijuana use for gaining acceptance from peers. It was suggested that this might reflect the selective survival into Grade 13 in the sampled community of more independently-oriented students.  相似文献   
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