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961.
This study compared effectiveness of the concentration period in two groups of shooters to evaluate the influence of their expertise while concentrating on the target. Marksmen (pistol shooters, 10 men and 5 women) and pentathletes (6 men and 7 women) took part in a shooting competition in keeping with the rules of each event. Participants were then asked to imagine themselves shooting, at the laboratory. Five variables representing the activity of the autonomic nervous system were continuously recorded (skin resistance and potential, skin blood flow, skin temperature, instantaneous heart rate). Autonomic responses recorded during concentration, actual shooting, and mental imagery were compared by calculating the ratios concentration/ shooting and imagery/shooting. The resultant mean ratio was used to characterize each participant. The same autonomic nervous system pattern was observed during concentrating on the target, mental imagery, and actual shooting. However, marksmen showed ratios closer to 1.0 than pentathletes, absolute mean differences being .06 and .3, respectively. Shorter duration and weakest amplitude responses were recorded during the concentration phase in the Pentathlete group, suggesting that they have more difficulty in using mental imagery during competition than marksmen. When subjects performed well, a specific response pattern was observed in the Marksman group, but not in the Pentathlete group, except in skin potential. In both Marksman and Pentathlete groups, a majority of negative skin potential responses were found in the concentration and shooting phases for the best shots.  相似文献   
962.
Considering exercise has positive and negative reinforcing properties, the mood states of sedentary, nonexercise-dependent and exercise-dependent volunteers were compared after maximal exercise testing. Mood status was evaluated by the Beck Depression Inventory, Trait-State Anxiety Inventory, and Profile of Mood States (POMS). No differences were detected before the test or after it, indicating little possibility of positive reinforcement. However, a significant reduction in the POMS Tension-Anxiety scores was observed in both exerciser groups (greater in the exercise-dependent group) but not in the sedentary group. Only in the exercise-dependent group were significant reductions in Anger and Total Mood Disorders scores observed compared with their pre-exercise scores. These data suggest that exercising has stronger negative reinforcement properties for exercise-dependent volunteers and is a factor which could increase the odds of their becoming dependent on exercise.  相似文献   
963.
Two experiments in reasoning by analogy were conducted to study the role of inducing source difficulty by reducing the salience of the source's structural elements. Three nonexclusive hypotheses were tested. According to the first, a difficult source problem improves analogical transfer because it increases the probability that the subject will notice the similarity between the source and the target. For example, errors made on both the source and the target can enhance the subject's awareness of the similarity between the two problems. According to the second hypothesis, a source that is difficult to solve is memorized better than an easier source. According to the third, source-problem difficulty affects the degree of abstractness in the representation of the solution elaborated by subjects. Experiment 1 showed that the higher frequency of spontaneous transfer between the source and the target when the source problem was difficult (Gick & McGarry, 1992) could be replicated in a cued-transfer situation. Experiment 2 showed that subjects given a difficult source, one in which the important element was not very salient, were better at categorizing isomorphic problems on the basis of structural features than were subjects given an easy source. The discussion deals with the implications of these results for the hypotheses tested and, more generally, for reasoning by analogy and education in general.  相似文献   
964.
We evaluated the role of the medial prefrontal cortex (mPFC) in the elaboration of egocentric navigation strategies in a water maze (WM). Lesions of mPFC cell bodies was achieved in 21 rats using bilateral injections of ibotenic acid (IA); 13 control rats were injected with saline. After 17 days, rats had to learn an allocentric (using external cues: 10 lesioned, 7 saline rats) or an egocentric WM (using internal/kinetic cues: 10 lesioned, 6 saline rats) over six trials in a same session. The initial trajectory on the sixth trial was used as an index of the elaboration of a navigation strategy. In the egocentric test, lesioned rats were more rarely located in the target quadrant than control rats. No differences were found between lesioned and control rats in the allocentric test. These results show that lesions of the mPFC impairs the capacity to elaborate an egocentric navigation strategy.  相似文献   
965.
Exposure is a highly effective treatment for pathological fear and anxiety, but rarely used in routine care. Issues of practicability and lack of therapists in rural areas are main barriers for the dissemination of exposure. Smartglass devices may enable therapists to guide exposure from their own office via real-time feedback and may thereby increase practicability. The present study explored the technological usability and clinical feasibility of Smartglass-guided exposure in a behavioral approach test in spider-fearful individuals (N = 40).Fearful individuals were asked to start the Smartglass themselves and established a connection to a therapist, who guided the exposure test from afar. Clinical severity of spider fear was assessed via questionnaire. Technological usability was assessed with established measures of usability, user experience, and user acceptance. Exploratory, individual characteristics of exposure were collected (e.g., within-session fear reduction, duration, safety behavior).Overall, fearful individuals (94.9%) and therapists (100%) were able to establish a connection. Usability of Smartglass-guided exposure was evaluated as positive. Within-session fear reduction was large (d = 1.91). Adverse events were minimal. There were, however, some associations between exposure characteristics and usability evaluation (e.g., lower user-friendliness and exposure duration). Two case examples further highlight chances and risks of Smartglass-guided exposure.These findings provide first evidence that Smartglass-guided exposure could be useful in exposure therapy. Smartglass-guided exposure may ultimately help to increase practicability of exposure and increase dissemination, also in rural areas. These findings are promising for future research on the long-term outcome of evidence-based exposure in treatment seeking patients.  相似文献   
966.
967.
The misclassification error distance and the adjusted Rand index are two of the most common criteria used to evaluate the performance of clustering algorithms. This paper provides an in-depth comparison of the two criteria, with the aim of better understand exactly what they measure, their properties and their differences. Starting from their population origins, the investigation includes many data analysis examples and the study of particular cases in great detail. An exhaustive simulation study provides insight into the criteria distributions and reveals some previous misconceptions.  相似文献   
968.
Psychometrika - Complex interactive test items are becoming more widely used in assessments. Being computer-administered, assessments using interactive items allow logging time-stamped action...  相似文献   
969.
Philosophical Studies - The fitting attitude analysis of value states that for objects to have value is for them to be the fitting targets of attitudes. Good objects are the fitting targets of...  相似文献   
970.
Background/Objective: The aim was to evaluate the evolution of depressive symptoms and to explore the influence of physical activity (PA) practice during the home confinement due to the COVID-19 outbreak in Spain. Method: Information was collected from 595 confined participants who reported personal and contextual information, depressive symptoms and PA levels at four time points. Results: The changes in depressive symptoms were analyzed using a linear mixed model with cubic splines. Results showed a significant increase, with a significant rise between T1 and T2 (OR = 2.38, 95% CI = 1.83-3.10). It continued growing until T4 (OR = 2.93, 95% CI = 1.97-4.38). A negative relationship was observed between the increase in depressive symptoms and moderate-to-vigorous physical activity (MVPA) levels, with a significant slope up to 4 hours of MVPA per week (OR = 0.51, 95% CI = 0.29-0.90) that tended to increase until 16 hours per week of MVPA (OR = 0.41, 95% CI = 0.20-0.87). Conclusions: Results from a partition model showed that moderate intensity of PA could be enough to prevent an increase of depressive symptoms during home isolation.  相似文献   
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