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71.
In two experiments we studied developmental changes in reasoning about intensive quantities. In contrast to previous studies, color--an intensive quantity that is readily perceivable--was chosen as stimulus material. Children between 6 and 12 years of age and adults predicted the mixture intensity of pairs of liquids with different intensities of red color, the liquid volumes in the two source glasses either being the same (Experiment 1) or different (Experiment 2). The data show that cognitive averaging in this domain develops late and slowly. An extensitivity bias, a strong tendency to use rules (adding in particular) that hold for extensive but not for intensive quantities, predominated up to the age of 12 years and was not totally absent in adults. Contrary to common expectation, children's use of the correct averaging rule became more likely when an extensive quantity, volume, was also varied and thus the task increased in complexity.  相似文献   
72.
Whether lung transplantation improves Health-related Quality of Life in patients with emphysema and other end-stage lung diseases before and after lung transplantation was examined. Between 1992 and 1999, 23 patients with emphysema and 19 patients with other indications completed self-administered questionnaires before lung transplantation, and at 4, 7, 13, and 25 mo. after transplantation. The questionnaire included the Nottingham Health Profile, the State-Trait Anxiety Inventory, the Self-rating Depression Scale, the Index of Well-being, the self-report Karnofsky Index, and four respiratory-specific questions. Neither before nor after transplantation were significant differences found on most dimensions of Health-related Quality of Life between patients with emphysema and other indications. Before transplantation, both groups report major restrictions on the dimensions Energy and Mobility of the Nottingham Health Profile, low experienced well-being, depressive symptoms, and high dyspnea. About 4 mo. after transplantation, most Health-related Quality of Life measures improved significantly in both groups. These improvements were maintained in the following 21 mo.  相似文献   
73.
Cross-situational stability in parents' emotional warmth and guidance was studied by observing parents (N = 77, M age = 38 years) with their school-aged child in 2 dyadic problem-solving situations and in a family discussion concerning a moral dilemma. The observational data were coded by independent observers using dimensional ratings and dichotomous frequency counts as the 2 coding procedures. These procedures yielded a similar pattern of findings. Parents tended to behave consistently across situations, although the type of situation did affect the amount of emotional warmth and guidance manifested by the parent. Stability was further analyzed by means of structural equation modeling to test whether variance in parents' emotional warmth and guidance across situations was attributable to a generalized parenting style factor. A Parenting Style factor was identified that reflected the parents' child-centeredness; this factor explained, in part, parental behavior within each situation, although contextual factors also contributed to situation-specific variations from task to task.  相似文献   
74.
Four experiments explored how readers use temporal information to construct and update situation models and retrieve them from memory. In Experiment 1, readers spontaneously constructed temporal and spatial situation models of single sentences. In Experiment 2, temporal inconsistencies caused problems in updating situation models similar to those observed previously for other dimensions of situation models. In Experiment 3, merely implied temporal order information was inferred from narratives, affecting comprehension of later sentences like explicitly stated order information. Moreover, inconsistent temporal order information prevented the creation and storage in memory of an integrated situation model. In Experiment 4, a temporal inconsistency increased processing time even if readers were unable to report the inconsistency. These results confirm the significance of the temporal dimension of situation models.  相似文献   
75.
Brain activity elicited by visually presented words was investigated using behavioral measures and current source densities calculated from high-resolution EEG recordings. Verbs referring to actions usually performed with different body parts were compared. Behavioral data indicated faster processing of verbs referring to actions performed with the face muscles and articulators (face-related words) compared to verbs referring to movements involving the lower half of the body (leg-related words). Significant topographical differences in brain activity elicited by verb types were found starting approximately 250 ms after word onset. Differences were seen at recording sites located over the motor strip and adjacent frontal cortex. At the vertex, close to the cortical representation of the leg, leg-related verbs (for example, to walk) produced strongest in-going currents, whereas for face-related verbs (for example, to talk) the most in-going activity was seen at more lateral electrodes placed over the left Sylvian fissure, close to the representation of the articulators. Thus, action words caused differential activation along the motor strip, with strongest in-going activity occurring close to the cortical representation of the body parts primarily used for carrying out the actions the verbs refer to. Topographically specific physiological signs of word processing started earlier for face-related words and lasted longer for verbs referring to leg movements. We conclude that verb types can differ in their processing speed and can elicit neurophysiological activity with different cortical topographies. These behavioral and physiological differences can be related to cognitive processes, in particular to lexical semantic access. Our results are consistent with associative theories postulating that words are organized in the brain as distributed cell assemblies whose cortical distributions reflect the words' meanings.  相似文献   
76.
Visual perception in 'low vision'   总被引:1,自引:0,他引:1  
Hyvärinen L 《Perception》1999,28(12):1533-1537
'Low vision' has an international classification as an impairment of vision that is defined by loss of visual acuity and the size of the visual field. Functional classification that would depict capability to use vision in different activities has not yet been agreed upon. Abnormal visual information leads to changes in visual perception, and brain-damage-related visual impairment may alter or prevent one or several cognitive visual functions. Abnormal visual perception opens a window into brain mechanisms that the psychophysicists otherwise do not have. Together with clinicians, psychophysicists can help visually impaired persons to understand the nature of their disability by thoroughly studying the nature of the altered image and the profile of cognitive visual functions.  相似文献   
77.
A guiding question for this special section, sparked by the increasing number of studies on callous –unemotional traits (CU traits) and the DSM-5 Limited Prosocial Emotion (LPE) specifier, is whether CU traits are enough to identify a clinically meaningful subgroup of youth with conduct problems or whether other psychopathic traits contribute. Seven empirical papers and two commentary papers address this question to varying degrees and in different ways with some papers “competing” various models against one another along with other papers investigating distinct correlates of the psychopathy factors. Findings across the papers suggest that there could be benefits to examining the broader construct of psychopathy in addition to examining its underpinning dimensions rather than CU traits alone. Two commentary papers also shed light on the importance of psychopathic traits in children with Conduct Disorder (CD) and provide insights for future work on this topic. It is hoped that the articles and commentary will generate new ideas for research and practice that could have implications for the treatment of those individuals with CD and psychopathic traits.  相似文献   
78.
The aim of this study was to compare two youth psychopathy models (i.e., callous-unemotional versus multidimensional model) in their ability to predict future and stable conduct problems (CP). At baseline, mothers and fathers of 321 boys and 369 girls (ages 7–12) completed measures that tap callous-unemotional and other psychopathic traits. Parent-reported CP was collected at baseline and at 6- and 12 month follow-ups. Children were assigned to mutually exclusive groups based on their levels of CP and psychopathic traits. Children with CP who manifested callous-unemotional traits (Callous-Unemotional?+?CP) were occasionally at risk for future and stable CP. Yet, across gender, children with CP scoring high on all psychopathic trait dimensions (Psychopathic Personality?+?CP) showed the most robust and highest risk for future and stable CP. Also, Callous-Unemotional?+?CP children, and children who were only high in CP, often were at similar risk for future CP. The findings suggest that the callous-unemotional model is less sufficient than the multidimensional model in predicting future and stable CP. This can be concluded for both boys and girls and calls for more research reconsidering the multidimensional nature of psychopathy for CP subtyping purposes.  相似文献   
79.
Decision makers typically overweight small probabilities and underweight large probabilities. However, there are recent reports that when probability is presented in the form of relative frequencies, this typical pattern reverses. We tested this hypothesis by comparing decision making in two tasks: In one task, probability was stated numerically, and in the other task, it was conveyed through a visual representation. In the visual task, participants chose whether a "stochastic bullet" should be fired at either a large target for a small reward or a small target for a large reward. Participants' knowledge of probability in the visual task was the result of extensive practice firing bullets at targets. In the classical numerical task, participants chose between pairs of lotteries with probabilities and rewards matched to the probabilities and rewards in the visual task. We found that participants' probability-weighting functions were significantly different in the two tasks, but the pattern for the visual task was the typical, not the reversed, pattern.  相似文献   
80.
Deficits in executive functioning and working memory associated with frontal lobe dysfunction are prominent in depression and work-related long-term sick leave (LTSL). This study used functional magnetic resonance imaging (fMRI) to investigate potential differences in brain activation patterns in these conditions. In addition, the function of the hypothalamic-pituitary-adrenal (HPA) axis was examined and compared between groups. Since there is a clear overrepresentation of women in these diagnostic groups, and to ensure a more homogenous sample population, only women were included. To examine the neural correlates of relevant cognitive processes in patients on sick leave >90 days due to work-related LTSL, recently diagnosed patients with major depression Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV criteria, untreated), and healthy controls (n?=?10, each group), a 2-back working memory task and a visual long-term memory task were administered during fMRI scanning. HPA axis functioning was investigated using a diurnal curve of saliva cortisol and a dexamethasone suppression test. Task performance was comparable among the three groups. Multivariate image analysis revealed that both memory tasks engaged a similar brain network in all three groups, including the prefrontal and parietal cortex. During the 2-back task, LTSL patients had significant frontal hypoactivation compared to controls and patients with depression. Saliva cortisol measurements showed a flattening of the diurnal rythmicity in LTSL patients compared to patients with depression and healthy contols. Taken together, these findings indicate that work stress-related LTSL and major depression are dissociable in terms of frontal activation and diurnal cortisol rhythmicity.  相似文献   
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