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现在,等值越来越受到各考试测验机构及测量学研究人员的重视,特别是项目反应理论等值的优越性更使他们有了信心。然而,很多人却没有注意到被试能力分布形态可能给等值结果带来的影响效果及程度。本研究以项目反应理论两级记分模型的项目参数等值在不同被试能力分布形态下的结果差异作为重点,探讨被试抽样偏差可能给项目特征曲线等值带来的误差问题。研究结果表明,被试能力分布形态会显著地影响项目参数等值的系数,特别地,能力分布的偏态系数与等值方程的截距存在显著的线性相关关系,但能力分布形态的变化对等值方程中斜率的影响并不明显 相似文献
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抑郁的遗传与环境交互作用(G×E)机制已成为富有挑战性的前沿课题之一。然而,既有G×E研究大多关注遗传基因与不利环境的交互作用,相对忽视了积极环境的影响。本研究以1025名青少年为被试,运用问卷法与 DNA分型技术,采用间隔3年的追踪设计(T1小学六年级—T2初中三年级),考察 MAOA基因rs6323多态性与母亲支持性教养对青少年抑郁的交互作用以及性别在其中的调节作用,并同时采用新兴的探索性与验证性方法检验G×E交互作用的素质–压力假说与不同易感性假说。结果显示, MAOA基因rs6323多态性与母亲支持性教养行为交互作用于女青少年的抑郁,母亲支持性教养显著负向预测 GG 基因型女青少年的抑郁,但对 TT基因型女青少年抑郁的预测作用并不显著,该交互作用符合不同易感性假说。MAOA基因 rs6323多态性与母亲支持性教养对男青少年的抑郁无显著交互作用。本研究发现推进了抑郁遗传机制的研究,并为不同易感性假说提供新的研究证据。 相似文献
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This study investigated the impact of demographic variables and nutritional status on adult cognitive functioning using structural equation modeling. Demographic variables that were considered were height, weight and gender, whilst nutritional status was measured on the Nutrition Assessment Inventory (NAI). Cognitive functions, such as executive cognitive functions, cognitive flexibility, cognitive ability and cognitive vulnerability were measured using the Amsterdam Executive Function Inventory (AEFI), the Cognitive Flexibility Scale (CFS), the Cognitive Ability Questionnaire (CAQ), and the Dysfunctional Attitude Scale Form A-Revised (DAS-A-R) respectively. Findings indicated that ethnicity and weight variables contribute to 8.8% of the nutritional status variations observed. A SEM analysis showed that nutritional status has an impact on 13% on the measured cognitive abilities of adults. The effects of “healthy nutrition”, “use of complementary nutritients”, “coping with high fat foods”, and “high fat food assumption” subscales of the nutrition scale were found to play a role in cognitive ability. This study shows a fitted SEM for the predictive roles of ethnicity, weight and nutritional status on the cognitive ability in adults. 相似文献
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There are individual differences in the rates of cognitive decline across later adulthood. Personality traits are among the factors that may account for these differences. The current project investigated whether personality traits were associated with trajectories of cognitive decline, and whether the associations were different before and after dementia diagnosis. The data was analyzed using linear mixed effects regression. Across study aims is a focus on replicability and generalizability. Each question was addressed in four independent longitudinal studies (EAS, MAP, ROS, SATSA), then meta-analyzed, providing estimates of replicability. Results indicated that low neuroticism and high openness were associated with total cognitive function. We detected evidence for cognitive decline in all four samples, and openness was associated with decline post dementia diagnosis. 相似文献
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Anna J. Cunningham Adrian P. Burgess Caroline Witton Joel B. Talcott Laura R. Shapiro 《Developmental science》2021,24(1)
We reconcile competing theories of the role of phonological memory in reading development, by uncovering their dynamic relationship during the first 5 years of school. Phonological memory, reading and phoneme awareness were assessed in 780 phonics‐educated children at age 4, 5, 6 and 9. Confirmatory factor analyses demonstrated that phonological memory loaded onto two factors: verbal short‐term memory (verbal STM; phonological tasks that loaded primarily on serial order memory) and nonword repetition. Using longitudinal structural equation models, we found that verbal STM directly predicted early word‐level reading from age 4 to 6, reflecting the importance of serial‐order memory for letter‐by‐letter decoding. In contrast, reading had no reciprocal influence on the development of verbal STM. The relationship between nonword repetition and reading was bidirectional across the 5 years of study: nonword repetition and reading predicted each other both directly and indirectly (via phoneme awareness). Indirect effects from nonword repetition (and verbal STM) to reading support the view that phonological memory stimulates phonemically detailed representations through repeated encoding of complex verbal stimuli. Similarly, the indirect influence of reading on nonword repetition suggests that improved reading ability promotes the phoneme‐level specificity of phonological representations. Finally, the direct influence from reading to nonword repetition suggests that better readers use orthographic cues to help them remember and repeat new words accurately. A video abstract of this article can be viewed at https://www.youtube.com/watch?v=70LZfTR0BjE . 相似文献
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