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971.
The concept of physical literacy (PL) has gained increasing attention over the last decade and posits that individuals value and take responsibility for engagement in physical activities for life through (a) motivation/confidence, (b) physical competence, and (c) knowledge/understanding. There is a mounting number of articles that have recently transformed the conceptual ideas of PL into interventions. The goal of this pre-registered (PROSPERO CRD42020188926) systematic review was to analyze and summarize PL interventions in terms of design and content. A total of 18 databases were searched drawing on the 2020 preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Inclusion criteria were English language, publication by November 2020, and interventions based on or inspired by PL. Articles that met these criteria were analyzed in relation to basic delivery characteristics, theoretical foundations, study objectives, intervention content, and potential links between the PL domains (a-c) and content. The multiphase screening process with two independent raters yielded 44 eligible interventions across 46 articles. The analyses of the review demonstrated that the majority of interventions were conducted on children or adolescents and in countries with higher economic development. While 77.3% of the interventions adopted a holistic understanding of PL, only 38.6% formulated study goals or intervention content to cover all the core PL domains. Importantly, only 25.0% of the interventions showed substantial links between PL domains and intervention content and can thus be classified as theory-based. Taken together, most interventions targeted aspects of physical competence (84.1%), whereas knowledge/understanding (59.1%) and motivation/confidence (47.7%) were often neglected. Therefore, future interventions should commit to systematically address all domains of PL simultaneously. PL interventions exposed weaknesses in reporting delivery characteristics and content. Finally, a model is suggested which assumes that practical PL efforts may better harmonize with PL theory and conception if they cultivated a tight interlocking with the three core domains of PL at all stages of the intervention process.  相似文献   
972.
973.
The increased risk of falls in the older aged population demands the development of assistive robotic devices capable of effective balance support. For the development and increased user acceptance of such devices, which provide balance support in a human-like way, it is important to understand the simultaneous occurrence of entrainment and sway reduction in human-human interaction. However, sway reduction has not been observed yet during a human touching an external, continuously moving reference, which rather increased human body sway. Therefore, we investigated in 15 healthy young adults (27.20±3.55 years, 6 females) how different simulated sway-responsive interaction partners with different coupling modes affect sway entrainment, sway reduction and relative interpersonal coordination, as well as how these human behaviours differ depending on the individual body schema accuracy. For this, participants were lightly touching a haptic device that either played back an average pre-recorded sway trajectory (“Playback”) or moved based on the sway trajectory simulated by a single-inverted pendulum model with either a positive (Attractor) or negative (Repulsor) coupling to participant's body sway. We found that body sway reduced not only during the Repulsor-interaction, but also during the Playback-interaction. These interactions also showed a relative interpersonal coordination tending more towards an anti-phase relationship, especially the Repulsor. Moreover, the Repulsor led to the strongest sway entrainment. Finally, a better body schema contributed to a reduced body sway in both the “reliable” Repulsor and the “less reliable” Attractor mode. Consequently, a relative interpersonal coordination tending more towards an anti-phase relationship and an accurate body schema are important to facilitate sway reduction.  相似文献   
974.
ObjectiveLatent class modeling (LCM) offers a promising approach for examining correlates of heart rate (HR) patterns over multiple exercise sessions. This research examined biological and psychological variables associated with different patterns of HR response to physical activity (PA).MethodsIn a three-arm randomized controlled trial (exercise video games vs. standard exercise vs. non-exercise control), HR was recorded during PA sessions over a 12-week period. LCM identified three patterns of HR during PA across 189 participants in active arms: 1) high HR across sessions with low variability within sessions, 2) linear increase in HR across sessions with low variability within sessions, and 3) high variability in HR across all sessions. Associations with biological (resting heart rate, blood pressure, BMI, age, cholesterol, triglycerides, HbA1c) and psychological (depression, motivations for PA, PA-induced feelings) predictors of latent class membership were iteratively tested.ResultsPsychological variables played as important a role in the final model as biological variables for predicting latent class membership. Few differences were found between LC1 and LC2, but LC3 differed from the other two groups in that participants were likelier to report that they feel revitalized after PA (vs. LC1 and LC2), to be less motivated for PA (vs. LC1), reported greater depression (vs. LC1 and LC2), and were younger (vs. LC1).ConclusionsThese findings demonstrate the potential of LCM to identify biological and psychological factors associated with chronotropic responses to PA, and advance understanding of the role of psychological factors in chronotropic PA outcomes.  相似文献   
975.
Kuhlmann''s Living Walden Two (2005) offers a social history of the actual experimental communities that were inspired by Skinner''s (1948) utopian novel. In the course of her examination, the author presents a reasonably accurate overview of the key cultural design elements described in the novel, of behavioral philosophy applied to cultural design, and of the academic reaction to the behavioral philosophy embodied in the fictional community. She is critical of several key behavioral tenets, but generally remains analytical rather than emotional. Kuhlmann concludes that contextual and individual factors undermined the capacity of most of the experimental communities inspired by Walden Two to sustain themselves.  相似文献   
976.
This study examined the factorial structure of psychosocial adaptation to chronic illness and disability in a sample of 313 individuals who sustained spinal cord injury (SCI). Three models were examined. The first model tested the hypothesis that psychosocial adaptation is composed of a single, global factor, in which positive (adaptive) and negative (nonadaptive) reactions define two opposing poles of the same dimension. The second model tested the validity of two distinguishable factors, representing adaptive and nonadaptive dimensions. The third model examined the relationship between the 2-factor model and a third dimension, that of denial. The data from the instruments measuring psychosocial adaptation to trauma and disability (the Reactions to Impairment and Disability Inventory and the Purdue Posttraumatic Stress Disorder-Revised) were submitted to a series of confirmatory factor analyses, and the results from the goodness of fit tests and fit indices provided strong support to the validity of the latter two models. The findings indicated that the structure of adaptation to SCI can be best conceptualized as representing two, moderately linked but clearly distinguishable, factors and that the construct of denial of disability further elucidates our understanding of the structure of adaptation to loss of body integrity.
Hanoch LivnehEmail: Phone: (503)725-4719
  相似文献   
977.
This article presents a discussion of the principle of extracortical organization of higher mental functions and its significance for the development of contemporary neuropsychology. The role of external factors (stimulus-mediator, symbol) in establishing functional connections between various brain systems is, in principle, universal. However, inasmuch as differing mediators and means, or significantly different details within them (direction of writing, orientation by maps or by the behavior of sea birds, etc.) may and in fact do develop in different cultures, neuropsychological analysis must take into account cross-cultural differences. Diagnostic tools must also be adapted to differing cultural contexts. The efficacy of this principle for the analysis of bilingual aphasia and of mental organization of speech, including the effect of acquisition of literacy in native language, is demonstrated. The importance of this principle for the development of new directions in applied neuropsychology is also discussed.  相似文献   
978.
This paper offers a case study of the origins, emergence, and evolution of the term cumulative record as the name for the means by which B. F. Skinner brought his behavior under the control of his subject matter. Our methods included on-line searches, reviews of Skinner's publications, and journal codings and counts. The results reveal that the term is not originally attributable to Skinner, but emerged earlier in ordinary language and in another discipline--education. It was not even original to Skinner in print in his own science. Still, the term was once original to him, which we address with additional analyses of his having originated and advanced it. We conclude with a discussion the constraints of our methods, suggestions for future research, and the variable appreciation of technology and terminology in science studies.  相似文献   
979.
Performing the vertical jump: movement adaptations for submaximal jumping   总被引:1,自引:0,他引:1  
The purpose of this study was to gain insight into the kinematics and kinetics of the vertical jump when jumping for different heights and to investigate movement effectiveness as a criterion for movement control in submaximal jumping. In order to jump high a countermovement is used and large body segments are rotated, both of which consume energy which is not directly used to gain extra jump height. It was hypothesized that the energy used to reach a specified jump height is minimized by limiting the non-effective energy consumed. Standing vertical jumps attempting 100%, 75%, 50%, and 25% of maximal height were performed by a group of 10 subjects. Force and motion data were recorded simultaneously during each performance. We found that jump height increased due to increasing vertical velocity at take off. This was primarily related to an increase in countermovement amplitude. As such, flexion amplitude of the hip joint increased with jump height whereas the ankle and knee joint flexion did not. These findings revealed that for submaximal jumping a consistent strategy was used of maximizing the contribution of distal joints and minimizing the contribution of proximal joints. Taking into account the high inertia of proximal segments, the potential energy deficit due to countermovement prior to joint extension, the advantageous horizontal orientation of the foot segment during stance and the tendon lengths in distal muscles, it was concluded that movement effectiveness is a likely candidate for the driving criterion of this strategy.  相似文献   
980.
Previous postural studies of traumatic brain injury (TBI) patients have been limited to identifying deficits in static and quasi-dynamic postural control tasks such as weight shifting. In this study, we examined whether or not patients with TBI are able to scale adequately their postural adjustments during the performance of the dynamic task of bimanual load-lifting. An age matched group of healthy adults served as controls. We used the Tetrax posturography system that calculates a stability score (ST) based on fluctuations in vertical ground reaction forces, normalized for body weight. During quiet standing, the ST scores of the TBI group were significantly higher than the control group. Forward weight shift and percentage change in the vertical ground reaction forces (lift postural adjustment (LPA) and post-lift postural adjustment (PLPA) scores) linearly increased with increasing load weight in both healthy and TBI subjects. Group differences were found in the magnitude of forward weight shift but not in the relative increase of the LPA and PLPA scores during the lifting and post-lifting phases respectively. The forward weight shift of the TBI group was lower-than-normal and asymmetrical--there was significantly less forward weight shift on the more affected than on the less affected limb. In addition, a significant amplitude coupling was found between the scaling of the weight shift of the heel and forefoot of each limb. However, no coupling was found between the weight shift amplitudes of homologous parts of both limbs in the TBI group. The results showed that scaling based on prior experience was preserved in the TBI group, though some TBI subjects demonstrated absent scaling in either the more affected or less affected heel or forefoot. The differences between the normal and TBI groups in postural adjustments are not necessarily a sign of pathology; rather they may represent a deliberate choice of the central nervous system to counteract predictable disturbances.  相似文献   
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