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921.
This study investigated whether Alzheimer's disease (AD) disrupts the basic organization of the semantic attributes of concepts. Young and normal older subjects and AD patients were presented with a target concept followed by a stimulus word and were to decide whether the stimulus was related to the target. On those trials where it was, the stimulus was either a high-, medium-, or low-dominance attribute of the target. The higher the normative dominance, the more important the attribute to concept meaning. In all 3 subject groups, decision time varied as a function of dominance. The higher the dominance, the faster the decision. Attribute dominance affected the performance of AD patients more than that of normal subjects. These results suggest that AD patients retain their knowledge of the relative importance that the different attributes of a concept have for concept meaning.  相似文献   
922.
Two hundred twelve bereaved elders rated marital adjustment using items drawn from the Locke and Wallace (1959) Marital Adjustment Test and completed the Beck Depression Inventory 2 months, 12 months, and 30 months after the loss of their spouses. Their responses were compared with those of 162 nonbereaved individuals of comparable age who were tested at the same times. More positive ratings of marital adjustment were made by bereaved subjects than by nonbereaved subjects. Among nonbereaved elders, more severe ratings of depression were associated with lower ratings of marital adjustment. In the bereaved sample, however, the opposite was found: More severe ratings of depression were associated with higher ratings of marital adjustment. This pattern of results changed only slightly over the 2.5-year course of bereavement and was not influenced by gender. These results are discussed in terms of cognitive processes (e.g., idealization) that influence retrospective assessments of marital adjustment during bereavement.  相似文献   
923.
Graphic designers and an experimental psychologist worked together to improve the design of two map symbols which are frequently confused: the symbols for cuttings and embankments on topographic maps. The problem was analysed in terms of the function of the symbols and their likely cognitive representations. Tests were developed to evaluate alternative designs, including an intervisibility task which requirred users to visualize the landform from the symbols viewed in the context of a map. Tests were given to schoolchildren and to experienced map users in order to compare the standard symbols with five alternative designs. Children's performance was strongly affected by the symbols they used, but experienced users were much less affected. After some refinement of the symbols a further experiment demonstrated the superiority of a number of alternative designs over the existing symbols on a range of test: scores were almost double on the intervisibility task. The paper makes recommendations to cartographers and argues for greater consideration of the inexperienced map user in the design process.  相似文献   
924.
Recent studies have called for the abandonment of the relative-time-spent scale in task inventories. This recommendation is based on findings that the job profile created with the scale data is highly correlated with the profile created from a much simpler “Do you perform this task?” checklist. We examined this issue using 3 inventories and 42 jobs (N=2252). Profile correlations were computed on only the tasks actually performed by incumbents to avoid possibly inflated rs due to including irrelevant tasks. The specificity of task inventory items was proposed as an explanation for the high correlation between the two job profiles. Specificity of items was examined by looking at both the type (job duties versus tasks) and the amount (number of items in job profile and average number of items relevant to each job) of items used in the inventory. Correlations between time spent and checklist profiles were in the .80's and .90's regardless of the number of irrelevant tasks or the specificity of tasks. We agree with previous military research and conclude that the relative-time-spent scale has limited incremental utility beyond a dichotomous checklist.  相似文献   
925.
Although malingering, or the manipulation of data by the patient, is a problem commonly faced by neuropsychologists, there has been little systematic investigation of this problem. This paper reviews the literature on the detection of malingering in assessment instruments commonly used by clinical neuropsychologists. Criticism of previous research is discussed, and suggestions are made both for future research and for clinical practice.  相似文献   
926.
Critical Flicker Fusion Thresholds (CFFTs) were measured in 644 elderly people identified from community-based general practice records, and the relationship of CFFT with age was investigated. The CFFT was measured using the method of limits with mean scores for three ascending (flicker/fusion) and three descending (fusion/flicker) presentations being recorded. The difference between the ascending and descending means was found to be significantly correlated with age (r=−0.131,P<0.001) and may reflect a reduced sensitivity of the Central Nervous System to suprathreshold flicker with increasing age. The results suggest that CFFT measurement has an important role to play in gerontological research as an objective measure of cognitive aspects of the ageing process.  相似文献   
927.
A 2-choice, operant-conditioning-based classification procedure was developed in which vervet monkeys (Cercopithecus aethiops) categorized species-typical snake and eagle alarm calls recorded from individually identified free-ranging animals. After preliminary training with a pair of calls from a single animal, 2 vervets were tested with novel exemplars produced by a variety of callers. Experiment 1 combined testing with continued training in routine classification of 14 new calls. In Experiment 2, the subjects were tested with 48 novel calls in rapid succession. Human (Homo sapiens) control subjects participated in the first study without extended preliminary training. Monkey and human subjects both showed immediate transfer to classification of unfamiliar alarm calls, despite variations both in voice characteristics and reproduction quality.  相似文献   
928.
Patterns of manual preference and the extent to which preference provided a benefit in performance (movement time) were evaluated in 7 young adult capuchin monkeys (Cebus apella). Directions of preference were inconsistent within individual animals across home-cage activities, unimanual, and bimanual experimental tasks. Preferences were more strongly expressed in the experimental tasks than in the home cage. A left bias in the population for prehension, predicted by recent theories, was not evident in any setting. Movement time was moderately negatively correlated with degree of preference within experimental tasks. The benefit to performance conferred by lateral preference was not dependent on whether the right or left hand was preferred. Lateralization of prehension appears to be a flexible process in these monkeys, which can result in quickly realized benefits in some conditions.  相似文献   
929.
In a panel study, more than 200 older adults were interviewed before and after a severe flood in southeastern Kentucky in 1984. The issue in this study was whether older adult flood victims were differentially vulnerable to increases in psychological and physical symptoms on the basis of their age, sex, marital status, occupational status, education level, and preflood symptom levels. Flood exposure was related to increases in depressive, anxiety, and somatic symptoms at 18 months postflood. Within this older adult sample, men, those with lower occupational status, and persons aged 55-64 were at significantly greater risk for increases in psychological symptoms. Sociodemographic status did not moderate the impact of flood exposure on physical health. Implications for crisis-intervention services to older adult disaster victims are discussed.  相似文献   
930.
Humility training is conceptualized as an appropriate treatment for persons who occasionally describe themselves, but are most frequently described by others as overbearing, insensitive and deceitful. Procedures are outlined to identify unrecognized fears and improve interpersonal skills. Humility is presented as a counterpoint to assertiveness and aggression/anger control interventions.  相似文献   
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