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991.
992.
"脑死亡=死亡"生物医学定律的逻辑论证 总被引:2,自引:2,他引:0
心脏具有顽固自律性、可多次复苏性、功能可人工替代性、可多次置换性四大特点,因而已失去作为死亡判定权威器官的地位.而大脑由于具有统领性、损坏后不可恢复性、功能不可替代性、全脑不可置换性四大特点,已替代心脏成为死亡判定的靶器官."脑死亡=死亡"在相当长时期内都将是一个严格的科学定义. 相似文献
993.
六艺与六经的关系,乃课程与课本的关系,二者不能完全等同起来,六艺除了六经还包括解释六经的传.经之得名,乃对传而言,并非推崇六艺的产物.六艺是从课程的角度对诗、书、礼、乐、易、春秋的总称,六经是从课本的角度对诗、书、礼、乐、易、春秋的总称.汉朝人在使用诗、书、礼、乐、易、春秋等概念的时候,有时是从课程的角度出发的,有时是从课本的角度出发的.至于六艺为何会出现礼、乐、射、御、书、数和诗、书、礼、乐、易、春秋两种不同说法,则与中国教育史上的一场变革有关. 相似文献
994.
Environmental issues are some of the most pressing threats the world is facing nowadays. In this context, motivating individual pro-environmental behavior becomes highly relevant. One strategy is to harness people's pro-environmental dispositions (e.g., biospheric values, pro-environmental attitudes). Although acknowledging the need to behave pro-environmentally lies at the core of these dispositions, the extent to which they are reflected in day-to-day pro-environmental practices fluctuates to a great extent. How to bridge this gap between dispositions and behaviors in pro-environmentalism? This research tests a novel psychological solution, that is, to heighten subjective feelings of power. Power depicts people's control over their own and others’ outcomes. Two studies (total N = 338, with n = 200 in Study 1 and n = 138 in Study 2) manipulated people's situational sense of high versus low power (by recalling and writing about relevant incidents), measured pro-environmental dispositions (biospheric values in Studies 1 and 2; attitude toward a specific environmental cause in Study 2), and examined their effects on pro-environmental behaviors (spending time on environmental persuasion in Study 1 and spending money on environmental donation in Study 2). Overall, both studies revealed that pro-environmental dispositions predicted pro-environmental behaviors, but only when the actors were prompted to experience a high instead of a low sense of power. The findings illuminate power as an important and viable communication tactic—to orient people toward their dispositions and practice what they preach in pro-environmentalism. 相似文献
995.
The purpose of this study was to examine the effects of focus of attention cues on movement coordination and coordination variability in the lower extremity. Twenty participants performed the standing long jump under both internal and external focus of attention conditions. A modified vector coding technique was used to evaluate the influence of attentional focus cues on lower extremity coordination patterns and coordination variability during the jumps. Participants jumped significantly further under an external focus of attention condition compared with an internal focus of attention condition (p = .035, effect size = .29). Focus of attention also influenced coordination between the ankle and knee, F(6, 19) = 2.87, p = .012, effect size = .388, with participants primarily using their knees under the internal focus of attention, and using both their ankles and knees under the external focus of attention. Attentional focus cues did not influence ankle-knee, F(1, 19) = 0.02, p = .98, effect size = .02, or hip-knee, F(1, 19) = 5.00, p = .49, effect size = .16, coordination variability. Results suggest that while attentional focus may not directly influence movement coordination condition, there is still a change in movement strategy resulting in greater jump distances following an external focus of attention. 相似文献
996.
The negative impacts of excessive and problematic video game playing on both children and adults are attracting increasing concern. Based on self‐determination theory (SDT; Ryan & Deci, 2000), this study hypothesized that the three basic psychological needs of autonomy, competence, and relatedness are positively associated with purpose in life, which in turn acts as a protective factor against problem video game playing among Chinese young adult players. Through a questionnaire survey with a sample of 165 Chinese adults aged between 18 and 30 years (mean age = 22.7 years), we found that perceived autonomy, competence, relatedness, and purpose in life were all negatively correlated with problem game playing. The demographic and psychological factors explained 38% of the variances of problem game playing. Specifically, gender, perceived relatedness, and purpose in life emerged as the three most salient predictors of problem game playing among the Chinese young adults. The mediating role of purpose in life was evidenced and it was found that purpose in life mediated the influences of the psychological needs proposed by SDT on problem game playing. Moreover, young men were significantly more susceptible to problem game playing than their female counterparts. To conclude, psychological needs and purpose in life influenced Chinese young adults’ vulnerability to problem game playing directly or indirectly. Intervention programs that encourage social involvement and voluntary work, as well as counseling service that helps clients to search for life purpose, are suggested for intervening in problem game playing among Chinese young adults. 相似文献
997.
Backward slope walking was considered as a practical rehabilitation and training skill. However, its gait stability has been hardly studied, resulting in its limited application as a rehabilitation tool. In this study, the effect of walking direction and slope grade were investigated on the local dynamic stability of the motion of lower extremity joints and trunk segment during backward and forward upslope walking (BUW/FUW). The local divergence exponents (λS) of 16 adults were calculated during their BUW and FUW at grades of 0%, 5%, 10%, and 15%. Mean standard deviation over strides (MeanSD) was analyzed as their gait variability. Backward walking showed larger λS for the abduction-adduction and rotational angles of knee and ankle on inclined surface than forward walking, while λS for hip flexion-extension angle at steeper grades was opposite. No grade effect for any joint existed during BUW, while λS increased with the increasing grade during FUW. As to the trunk, walking direction did little impact on λS. Still, significant larger λS for its medial-lateral and vertical motion were found at the steeper grades during both FUW and BUW. Results indicate that during BUW, the backward direction may influence the stability of joint motions, while the trunk stability was challenged by the increasing grades. Therefore, BUW may be a training tool for the stability of both upper and lower body motion during gait. 相似文献
998.
Growing international research interest in negative-leadership behaviors prompts the need to examine whether measures of ineffective leadership developed in the United States are equivalent across countries outside the United States. B. J. Tepper's (2000) abusive supervision measure has been used widely inside and outside the United States and merits research attention on its construct equivalence across different cultural settings. The authors conducted a series of multigroup confirmatory factor analyses to investigate the measurement equivalence of this measure across Taiwan (N = 256) and the United States (N = 389). Configural invariance was established, suggesting that both U.S. and Taiwanese samples perceive abusive supervision as a single-factor concept. Furthermore, the establishment of partial metric invariance and partial scalar invariance suggests that the abusive supervision measure is applicable to crosscultural comparisons in latent means, construct variance, construct covariances, and unstandardized path coefficients with the caution that workers from different cultures calibrate their responses differently when answering some items. 相似文献
999.
This study investigated gender differences in anxiety and coping styles under the stress of intense military training. We surveyed Chinese female (n = 470) and male (n = 379) military officers who were surveyed during the third month of a 10-month intensive training program. Results indicated that state and trait anxiety were highly correlated in both women and men. In general, female officers had higher levels of anxiety, greater negative coping tendencies, and less perceived self-efficacy than their male counterparts. When compared with the norm, both women and men had significantly more positive coping strategies. A hierarchical multiple regression analysis showed factors that influenced male and female state anxiety. Avoidance, which was chosen by women more often than men, in general was less useful for female officers. The most common positive coping style for female officers was problem solving, whereas for men it was help seeking. We suggested that even female officers with lower mental health levels than their male counterparts made active cognitive changes to their coping styles when undergoing intense military training. 相似文献
1000.
A series of large-scale molecular dynamics simulations have been performed to investigate the tensile properties and atomistic deformation mechanisms for the nanostructured Cu with three typical microstructures: the hierarchical structure consisting of both twin-free grains (d?=?70?nm) and grains with bundles of smaller nanotwins (d?=?70?nm, λ?=?10?nm), the fully nanograined structure and the fully nanotwinned structure. The average flow stress of the hierarchically structure is found to be higher than that calculated by rule of mixture. As compared with that of fully nanograined structure, the strength for the twin-free grains in the hierarchical structure is promoted and gives extra hardening due to the increased dislocation density and dislocation behaviours. It is also found that the nanotwin bundles are more deformable than the twin-free grains in the hierarchical structure according to the deviatoric strain invariant contour. This indicates that the fully nanograined structure cannot only be strengthened to a higher level, but also obtain better ductility by embedded with stronger bundles of smaller nanotwins. Thus, a superior strength–ductility synergy could be obtained in this kind of hierarchical structures, and this novel strategy has also been implemented in bulk austenitic steels or copper by recent experiments. 相似文献