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481.
Theories of perceptual transparency have typically been developed within the context of a physical model that generates the percept of transparency (F. Metelli's episcotister model, 1974b). Here 2 fundamental questions are investigated: (a) When does the visual system initiate the percept of one surface seen through another? (b) How does it assign surface properties to a transparent layer? Results reveal systematic deviations from the predictions of Metelli's model, both for initiating image decomposition into multiple surfaces and for assigning surface attributes. Specifically, results demonstrate that the visual system uses Michelson contrast as a critical image variable to initiate percepts of transparency and to assign transmittance to transparent surfaces. Findings are discussed in relation to previous theories of transparency, lightness, brightness, and contrast-contrast.  相似文献   
482.
The majority of therapy programs for people who stutter are aimed at modifying the entire speech output by using techniques that reduce the overt signature events. Use of these techniques for extended time periods are thought to induce true fluency that is automatic, natural, and effortless. It is proposed that the present form of therapeutic intervention induces pseudofluency rather than true fluency. Pseudofluency is the speech posrtherapy of persons who stutter, free of the discrete signature events of stuttering, but replaced by cognitively mediated gestures that are embedded as continuous prolongation or masked stuttering events throughout the speech act. This may account for the high rate of relapse and the problems associated with the maintenance, stability, and naturalness of speech after stuttering therapy.  相似文献   
483.
Previous work indicates that there may be a relationship between the observation and evaluation of one's physique and the construct of social physique anxiety associated with this process. Since physical educators are expected to serve as role models of desired fitness behaviors, bodily appearance, and composition, it is of interest to examine whether such responses and relationships may be observed. However, there is limited published information on anthropometric profiles and body images of physical education professionals, especially of those from India. Therefore, this study compared anthropometric profiles and Social Physique Anxiety in a sample of 182 male physical education professionals from India (M age=41.2 yr.). Body Mass Index, sum of three skinfolds (Tricep, Abdomen, and Thigh), and waist/hip ratio were determined using standard procedures. The sample was grouped into overweight and normal weight categories. Significant group differences were found for the sum of skinfolds and waist/hip ratio, with no significant differences between groups on the Social Physique Anxiety total score. Correlations for the anthropometric measures with the Social Physique Anxiety scores indicated no significant relationships. Mean total Social Physique Anxiety score for the combined group was comparable to those reported for other groups of physically active individuals. These findings indicate low Social Physique Anxiety in this sample and may have implications with regard to the attitudes pertaining to body image and role modeling of appropriate fitness behaviors.  相似文献   
484.
Eight patients (seven women), mean +/- SD T1 age 68.57 +/- 12.43 years, average educational level 5.83 +/- 3.70 years, had two Tc-99m ECD SPECT examinations separated by an average 8.49 +/- 5.59 months. Patients were imaged using standard Harlem Hospital acquisition and processing protocols with approximately 30 mCi of ECD on a Prism 3000 triple head gamma camera. Images were interpreted by an independent reader blinded to the patients' clinical history and imaging date. T1 psychiatric diagnosis was seven Alzheimer's dementia (AD) and one depression. Eight T1 images were interpreted as abnormal, six indicative of AD. Binomial 95% two-tail confidence interval for T1 agreement between diagnosis and interpretation was 0.25 0.63 0.92. T2 diagnosis was seven AD and one none. Seven T2 images were abnormal and indicative of AD, and one was normal. T2 confidence interval was 0.34 0.75 0.97. These findings suggest SPECT's value in assessing AD in uneducated socioeconomically disadvantaged geriatric patients.  相似文献   
485.
In three studies, an easy-to-apply response time task that differentiates between recognition and approach speed was applied. The results indicate that individuals recognized and approached positive stimuli faster than negative stimuli (Pilot Study). But, when the choice options differed less in valence, approach movement time was a better predictor of consumer choice and willingness to pay than recognition time (Study 1) and a better predictor of consumer choice than self-reports when the choice was made with an affective compared to a cognitive focus (Study 2). Moreover, approach movement time, but not recognition time correlated with other implicit measures.  相似文献   
486.
The authors examined the mediation of the attitude similarity–attraction relationship. When affect was the sole measured mediating variable, the hypothesized partial mediation held in Experiment 1 (N = 60). In Experiment 2 (N = 96), ratings of the 3 potential mediators (affect, inferred attraction, and cognitive evaluation) and of an irrelevant variable (inferred cognitive evaluation) were taken at 2 orders of mediator measurement. The attitude similarity-attraction link was more strongly mediated by inferred attraction than by cognitive evaluation. Surprisingly, however, the effect of affect on attraction was reversed in the multiple-mediation analysis. Post hoc analyses disclosed that affect transmitted the similarity effect from its preceding variable only to the succeeding one. Theoretical and methodological implications of the dominance of inferred attraction and the subtlety of affect are discussed.  相似文献   
487.
We tested the hypothesis that the attitude similarity effect spreads sequentially through positive affect, respect, and inferred attraction to attraction. In Experiment 1, participants received information about a partner's similar or dissimilar attitudes and reported one of the three mediators before attraction. The similarity-attraction link was mediated by positive affect or respect but more strongly by inferred attraction. In Experiment 2, the three mediators were measured in different orders. Results falsified parallel and combined parallel-sequential multiple-mediator models and two of the fully sequential multiple-mediator models but supported four fully sequential models that were consistent with the affect-centered and affect primacy hypotheses.  相似文献   
488.
The ductile fracture mechanism in a fine-grained magnesium alloy has been investigated by transmission electron microscopy-focused ion beam techniques. In coarse-grained or conventional magnesium alloys, twins form at the very beginning of the deformation process, and crack propagation occurs through the twin boundaries. However, in the alloy used in this study, subgrain structures were found instead of twins at the crack tip. Nanoscale twins formed subsequently owing to large stress in the crack propagation route. The fine-grained alloys showed high fracture toughness resulting from resistance to the twins at the beginning of the deformation.  相似文献   
489.

Extensive microstructural studies have been performed with respect to the formation of the icosahedral quasicrystalline phase and its relationship to other phases in Mg 95 Zn 4.2 Y 0.8 alloy. The icosahedral phase forms as an intergranular eutectic phase as well as precipitates in the matrix. The precipitates are nanosized (typically 50 nm) with a definite orientation relationship with the matrix, sharply faceted on twofold planes which are on the basal and prismatic planes of the matrix. The detailed crystallographic relationship with the matrix is described. The icosahedral phase is occasionally found to coexist with the cubic W-Zn 3 Mg 2 Y 3 phase with a definite crystallographic relationship.  相似文献   
490.
Observers were instructed to point with their right arm to a mirror image of their left shoulder. Instead of pointing to the target with their real arm, they occluded the target with their mirror-imaged finger, and their real finger pointed off to the left side of the target, facts that came as a surprise to them in debriefing. The occlusion by a mirror image finger was not done to avoid double images, since it occurred in monocular conditions. That it is due to planning before pointing can be inferred from the fact that it occurred in blindfolded conditions.  相似文献   
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