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251.
The current study tests whether the presence of callous–unemotional (CU) traits designates a group of children with conduct problems who show an especially severe and chronic pattern of conduct problems and delinquency. Ninety-eight children who were selected from a large community screening of school children in grades 3, 4, 6 and 7 were followed across four yearly assessments. Children with conduct problems who also showed CU traits exhibited the highest rates of conduct problems, self-reported delinquency, and police contacts across the four years of the study. In fact, this group accounted for at least half of all of the police contacts reported in the sample across the last three waves of data collection. In contrast, children with conduct problems who did not show CU traits continued to show higher rates of conduct problems across the follow-up assessments compared to non-conduct problem children. However, they did not show higher rates of self-reported delinquency than non-conduct problem children. In fact, the second highest rate of self-reported delinquency in the sample was found for the group of children who were high on CU traits but without conduct problems at the start of the study.  相似文献   
252.
The research on emotional intelligence (EI) has focused mainly on testing the incremental validity of EI with respect to general intelligence and personality; less attention has been devoted to investigating the potential interaction effects. In a self-presentation task that required participants to obtain positive evaluations from others, individuals low in IQ but high in EI performed as well as the high IQ individuals. In addition, the low emotionality individuals performed significantly higher when also high in EI. The results extend the previous findings on the compensatory effect of EI on low IQ to the domain of interpersonal effectiveness and shed light on the effective functioning of personality traits when interpreted with the interaction of EI. Overall this study suggests that the role of EI in predicting performance might have been overlooked by checking solely for main effects and illustrates new venues for understanding the contribution of EI in explaining emotion-laden performance.  相似文献   
253.
254.
Previous research has indicated that muscle fatigue due to repeated bouts of physical activity can have negative residual effects on balance; however investigations using multi-joint forms of exercise involved in everyday settings and determination of how control of posture is altered during the physical activity itself are limited. The purpose of this investigation was to evaluate alterations in postural stability before, during, and after prolonged multi-joint STS exercise in healthy young adults. Center of pressure (COP) acquisitions were collected during repetitive STS exercise, while voluntary limits of stability (LOS) testing was performed before, immediately after, and 10 min after STS exercise. By 50% total STS exercise time, fatigue resulted in increased anterio-posterior (y) and medio-lateral (x) COP path lengths (p = 0.003 and p = 0.018 respectively) and an anterior shift of COP at seat-off towards the mid-foot (p = 0.010). No significant change in LOS mean amplitude was found after STS exercise; however a significant fatigue effect resulted in increased COPy sway velocity at maximal lean positions (p = 0.006), but returned to PRE values after 10 min of rest. Declines in postural stability during repetitive STS exercise was associated with reduced control of COP, as well as a reduced ability to stably control COP at extreme postural limits; however, 10 min was adequate in young adults for recovery. These results may have important implications for monitoring fall risk due to acute bouts of exercise induced muscle fatigue from repetitive multi-joint activities such as the STS.  相似文献   
255.
Before commenting on the papers from a recent interdisciplinary gathering of scholars from China, Japan, Korea, and Taiwan, a case is made for regional academia conversations today, because international conferences, especially in the humanities and social sciences, are still dominated by “Western” traditions, discourse, and protocols. After touching on the relative stability or variability of phenomena and procedures in the natural sciences, humanities, and social sciences, political and cultural questions are considered along with some of the ongoing consequences of the East Asian adoption of the European model of the modern research university.  相似文献   
256.
We model developmental patterns in the stability of Big-Six personality markers over a two-year period in a multi-cohort panel study of adult New Zealanders (n = 3910). Structural Equation Models testing patterns of linear, quadratic and cubic effects identified considerable variation in the stability of most aspects of personality across the adult age range (20–80 years). Agreeableness showed a slight linear decrease in consistency with increasing age. Extraversion, Conscientiousness, Neuroticism, Openness to Experience, and Honesty–Humility exhibited quadratic ‘inverted U’ patterns of rank-order stability. Unlike Agreeableness, the two-year consistency of these other personality dimensions increased from young adulthood towards middle age, then decreased as people progressed toward old age. Implications for personality research and emerging trends are discussed.  相似文献   
257.
Older people are increasingly being encouraged to be more physically active but this may lead to physiological fatigue, tiredness and other effects, which, at high levels, can adversely alter postural stability. However, older adults rarely perform physical activity at high intensities. This study aimed to determine whether a single bout of moderate-intensity physical activity, similar to that experienced during daily living, alters dynamic postural stability, particularly among those at risk of falling. Thirty-one healthy young, 33 healthy older and 21 balance-impaired older, adults performed a rapid, voluntary step-up task before and immediately after a 14 min, self-paced, moderate-intensity physical activity protocol. Timing of step components from vertical ground reaction forces, mediolateral displacement of center of pressure, and onset and amplitude of hip abductor muscle activity were recorded during the step task. All groups demonstrated the same changes after the activity, with slightly shorter weight-shift phase duration, smaller displacement of the center of pressure towards the stance leg during weight shifting, and earlier onset of stance leg gluteus medius activity. These changes indicate improved coordination of the step task after activity. Thus this study showed that dynamic postural stability is not adversely affected immediately following moderate-intensity physical activity, even among balance-impaired elderly.  相似文献   
258.
Locomotion requires both proactive and reactive control strategies to maintain balance. The current study aimed to: (i) ascertain upper body postural responses following first exposure to a forward (slip) support-surface perturbation; (ii) investigate effects of repeated perturbation exposure; (iii) establish relationships between arms and other response components (trunk; center of mass control). Young adults (N = 11) completed 14 walking trials on a robotic platform; six elicited a slip response. Kinematic analyses were focused on extrapolated center of mass position (xCoM), bilateral upper- and forearm elevation velocity, trunk angular velocity, and step parameters. Results demonstrated that postural responses evoked in the first slip exposure were the largest in magnitude (e.g., reduced backward stability, altered reactive stepping, etc.) and preceded by anticipatory anterior adjustments of xCoM. In relation to the perturbed leg, the large contra- and ipsilateral arm responses observed (in first exposure) were characteristically asymmetric and scaled to the degree of peak trunk extension. With repeated exposure, xCoM anticipatory adjustments were altered and in turn, reduced posterior xCoM motion occurred following a slip (changes plateaued at second exposure). The few components of the slip response that persisted across multiple exposures did so at a lesser magnitude (e.g., step length and arms).  相似文献   
259.
Study designA prospective, observational study.ObjectivesTo assess the attentional demands of using haptic modalities during walking using a multi-task paradigm in young, healthy adults.SettingBiomechanics of Balance and Movement (BBAM) Lab, University of Saskatchewan.MethodsTwenty-two (12 male) young, healthy adults performed walking trials with and without a verbal reaction time (VRT) task, as well as with and without the use of haptic anchors and light touch on a railing. Walking performance was evaluated using normalized stride velocity and step width, and dynamic stability was evaluated using step width variability and medial-lateral margin of stability (ML MOS) and its variability.ResultsThere were no significant differences in VRT when walking with and without added haptic input and no interactions between the added VRT task and added haptic input. Step width increased and variability of the ML MOS increased during trials with the VRT task compared to trials without the VRT task. The ML MOS decreased when using both haptic tools with a greater decrease when using light touch on the railing compared to when using the haptic anchors. Normalized stride velocity and step width decreased when using light touch on the railing only.ConclusionBoth haptic tools affected stability during walking. Using the railing to add haptic input had a greater effect on walking stability and was the only haptic tool to affect walking performance. Attentional demands should be considered in future research and applications of adding haptic input during walking.  相似文献   
260.
Researchers have reported contradictory results on the effect of static and dynamic stretching on subsequent performance. Due to the importance of performance through static and dynamic stretching, the aim of this study is to investigate the acute effects of static and dynamic stretching protocols on local dynamic stability in lower extremity joint kinematics and muscular activities during pedalling using a nonlinear dynamics approach. Using a randomised crossover trial design, fifteen active males participated voluntarily in this research (mass: 69.02 ± 10.52 kg, height: 174.00 ± 6.74 cm, and age: 21.20 ± 1.47 years) and completed a pedalling trial in situations of without stretching (WS), after static (SS), and dynamic stretching (DS) of lower extremity. The lower extremity joint angles in the sagittal plane and the electrical activity of soleus, gastrocnemius medialis, tibialis anterior, vastus medialis, biceps femoris, and rectus femoris muscles were collected during 30 pedalling cycles at 70 rates per minute. The results of the repeated measure ANOVA indicated that the knee and ankle angle largest LyE was significantly lower in DS compared to WS and SS. The largest LyE in muscle activity is also significantly lower for all the muscles after DS compared to WS and SS (P ≤ 0.05). Regarding the positive effects of DS on the joints and the muscle activity local dynamic stability, it is suggested to use DS than SS in the warm-up program before repetitive activities like pedalling.  相似文献   
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