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Yi Lin 《Synthese》1989,79(3):473-488
In this paper, under the assumption that ZFC axiom system is consistent, the following are proved: (a) there is no system whose object set consists of all systems; (b) any system is not an object of itself; (c) any system is constructed with basic elements (elements which are not systems). Based on these results, the following problems in epistemology are discussed: the feasibility of the definition of the theory so-called science of science; the existence of basic particles in the world; and the existence of absolute truths.This paper was partially supported by Auburn University, presented atThe 20th Annual Spring Topology Conference, entitled The ZFC Axiom System and Problems in Epistemology. 相似文献
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实验使用电子计算机控制彩色图象显示器的屏幕来呈现视觉目标彩色光栅,以对人的颜色视觉进行对比感受性的测定。被试可以通过终端键盘改变光栅的各种变量并进行反应,计算机对结果进行记录和处理。实验Ⅰ是对比感受性作为红-绿光栅和绿色单色光栅的空间频率的函数的测定。结果表明,在所有空间频率上,被试对绿色光栅的对比感受性都比对红-绿光栅要高。但随着空间频率的升高,对两种光栅的对比感受性也相应升高,并都在中间空间频率带达到高峰值。实验Ⅱ是对颜色视觉对比感受性作为红-绿亮度比率的函数的测定。结果表明,空间频率和红色在光栅中的比率对对比感受性都有重要的影响。本实验结果具有明显的实际应用价值。 相似文献
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Fourth-, fifth-, and sixth-grade students responded to a questionnaire concerning their experiences with electronic videogames and computers. Teacher ratings of academic achievement, personality characteristics, and behavior patterns were also obtained for each student. These data were used to examine a number of hypotheses concerning potential harmful or beneficial effects of electronic videogames on school-age children, and to provide preliminary evidence concerning the correlates of computer usage by school-age children. Videogame usage showed significant positive correlations with teacher ratings of impulsivity, significant negative correlations with ratings of academic achievement, and little relationship to rated sociability. Videogame use also proved positively related to other social activities and to microcomputer use. 相似文献
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Nathan R. Todd Emily J. Blevins Jacqueline Yi Brett A. Boeh Bergmann Camarin G. Meno 《American journal of community psychology》2023,71(1-2):224-241
Dominant group members often are not aware of the privileges they benefit from due to their dominant group membership. Yet individuals are members of multiple groups and may simultaneously occupy multiple categories of dominance and marginality, raising the question of how different group memberships work in concert to facilitate or inhibit awareness of multiple forms of privilege. Examining awareness of privilege is important as awareness may be linked to action to dismantle systems of privilege that maintain oppression and inequality. Grounded in intersectional scholarship, in this study we examined how occupying intersecting categories of race/ethnicity, gender, and religion corresponded to an awareness of White, male, and Christian privilege. In a sample of 2321 Midwestern college students, we demonstrated that students from marginalized groups broadly reported greater awareness of all forms of privilege than students from dominant groups, and the difference between marginalized and dominant groups was most pronounced when the specific group category (e.g., gender) aligned with the type of privilege (e.g., male privilege). We also tested interactions among race/ethnicity, gender, and religion, only finding an interaction between race/ethnicity and religion for awareness of White and male privilege. These findings helped to clarify that multiple group memberships tended to contribute to awareness as multiple main effects rather than as multiplicative. Finally, we examined mean differences among the eight intersected groups to explore similarities and differences among groups in awareness of all types of privilege. Taken together, these findings quantitatively demonstrate the ways in which group memberships work together to contribute to awareness of multiple forms of privilege. We discuss study limitations and implications for community psychology research and practice. 相似文献
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Lee Shang Lin Tommy Ahmed Saheeb Horbal Logan Pietruszewski Thomas Hu Qingli Markus Etan J. 《Animal cognition》2023,26(2):703-708
Animal Cognition - Exploring new and unfamiliar environments is critical for survival, providing information on food, shelter, mates, and sources of danger. The open field paradigm is commonly used... 相似文献
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自闭症谱系障碍(Autism Spectrum Disorder, ASD)表现为社会交往困难以及重复刻板兴趣或行为。社交动机理论提出ASD个体是由于社交动机缺乏导致的社交障碍。目前该理论缺乏理论元素及结构关系的系统论证, 及基于此理论的低龄ASD儿童群体的研究证据。本研究拟采用心理实验法、眼动及近红外脑成像技术, 探索低龄ASD儿童早期社交奖赏、社交定向异常眼动标记及眶额叶脑区活动的神经机制。此外, 通过音乐奖赏强化学习的干预方式改善该理论的核心元素(社交奖赏), 观测能否改善ASD儿童的社交动机。本研究的开展有望对该理论进行系统验证, 并形成改善社交行为的潜在干预方案。 相似文献
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跨期选择是对不同时间点的得失的权衡与选择。伊索寓言《蚂蚁和蚱蜢》假借群居型昆虫的跨期选择偏爱暗喻投资未来的慢策略比只顾眼前的快策略更利于生存。用跨期选择领域通用的语言解读这一寓言便是:选择大而迟选项的蚂蚁比选择小而早选项的蚱蜢更可能扛过严冬而生存下来。为了探索何种跨期选择策略更有助于我们扛过疫情,本研究调查了亚非欧美大洋洲这5大洲18个国家共计26355名受测者对混合得失双结果的跨期选择偏爱,测量了人们平时和疫时跨期选择偏爱的变易程度(2类变易的程度指标),以及人们自评的扛疫成效。跨文化比较结果的主要发现是:不同通货的选择变易程度(指标1)和不同时期的选择变易程度(指标2)能联合预测中国/新加坡文化圈国民的自评扛疫成效;不同时期的选择变易程度(指标2)也可以单独预测印度/马来西亚/菲律宾/尼日利亚文化圈国民的自评扛疫成效;这2类选择偏爱变易的程度指标不能预测其他文化圈国民的自评扛疫成效(或者预测方向和假设相反)。基于易经“穷则变,变则通”的要旨和跨国比较的发现,我们认为:面临历史危机时善于变通的特长抑或成就了中华民族特有的竞争优势;在应对危机时,与中国文化距离越相近的国家或民族抑或也能... 相似文献
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Pessimistic explanatory style and response to illness 总被引:2,自引:0,他引:2
Previous studies have shown that a pessimistic explanatory style is a risk factor for illness, but the factors linking explanatory style and illness are unknown. One's characteristic response to poor health may mediate this relationship. Perhaps pessimistic individuals act helplessly in the face of their symptoms, thereby exacerbating disease. In the present study, we investigated this possibility by asking 96 young adults to complete measures of explanatory style, habitual response to illness, and ways of coping during their most recent episode of illness. Subjects who explain bad events pessimistically (with internal, stable, and global causes) reported more frequent illnesses during the past year and rated their overall health more poorly than those who habitually favor external, unstable, and specific explanations. When ill, the pessimistic subjects were less likely than their optimistic counterparts to take active steps to combat their illness. Our results suggest that one pathway leading from pessimistic explanatory style to poor health is mundane: passivity in the face of disease. 相似文献