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141.
142.
I study experimentally a single‐shot trust game where players have the opportunity to choose an avatar—a computer‐generated face—to represent them. These avatars vary on several dimensions—trustworthiness, dominance, and threat—identified by previous work as influencing perceptions of those who view the faces (Todorov, Said, Engell, & Oosterhof, 2008). I take this previous work and ask whether subjects choose faces that are ex ante more trustworthy, whether selected avatars have an influence on strategy choices, and whether individuals who evaluate faces as more trustworthy are also more likely to trust others. Results indicate affirmative answers to all three questions. Additional experimental sessions used randomly assigned avatars. This design allows me to compare behavior when everyone knows avatars are self‐selected versus when everyone knows they are randomly assigned. Random assignment eliminated all three effects observed when subjects chose their avatars.  相似文献   
143.
Repeated statements are more frequently judged to be true. One position relates this so‐called “truth effect” to metacognitive experiences of fluency, suggesting that repeated statements are more frequently judged to be true because they are processed more fluently. Although most prior research focused on why repetition influences truth judgments, considerably less is known about when fluency is used as information. The present research addresses this question and investigates whether reliance on fluency is moderated by learning experiences. Specifically, we focus on changes in the reliance on fluency over the course of time. A series of experiments reveals that fluency is more likely to be used in truth judgments when previous reliance on fluency has resulted in valid judgments, compared with when previous reliance on fluency was misleading. These findings suggest that reliance on fluency in judgments is a finely tuned process that takes prior experiences with fluency‐based judgments into account. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
144.
Every day we use products and treatments with unknown but expected effects, such as using medication to manage pain. In many cases, we have a choice over which products or treatments to use; however, in other cases, people choose for us or choices are unavailable. Does choosing (versus not choosing) have implications for how a product or treatment is experienced? The current experiments examined the role of choice‐making in facilitating so‐called expectation assimilation effects—or situations in which a person's experiences (e.g., discomfort and pain) are evaluated in a manner consistent with their expectations. In Experiment 1, participants were initially exposed to a baseline set of aversive stimuli (i.e., sounds). Next, some participants were given expectations for two “treatments” (i.e., changes in screen display) that could ostensibly reduce discomfort. Critically, participants were either given a choice or not about which of the two treatments they preferred. Participants in a control condition were not provided with treatment expectations. Results revealed that discomfort experiences assimilated to expectations only when participants were provided with choice. Experiment 2 replicated this finding and provided evidence against the idea that demand characteristics and choice‐making unrelated to the core task (i.e., choices without associated expectations) could account for the results. Further, Experiment 2 showed that choosing reduced discomfort because of increased positivity about the treatment. Results are discussed in the context of extant research on choice‐making and expectation effects. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
145.
研究胰岛素样生长因子结合蛋白2(IGFBP-2)及胰岛素样生长因子结合蛋白6(IGFBP-6)在结直肠癌中的表达及临床意义。采用免疫组织化学法及RT-PCR方法检测结直肠癌、结直肠腺瘤及癌旁正常黏膜组织中IGFBP-2及IGFBP-6的蛋白及mRNA的表达情况,结合临床病理资料进行统计学分析。IGFBP-2及IGFBP-6蛋白的阳性表达及mRNA的表达量在三组组织中均存在异常表达情况,且差异有明显的统计学意义(P〈0.05),在结直肠癌组IGFBP-2、IGFBP-6的阳性表达在肿瘤浸润深度、有无淋巴结转移及Duke's分期存在差异,有明显的统计学差异(P〈0.05)。临床可以把二者作为结直肠癌诊断及预后的早期预测指标。  相似文献   
146.
Testing effects have been well-established across a variety of studies involving school-age children. Specifically, children's test performance improves when they are given the opportunity to practice retrieval prior to the final test as compared to when practice involves only study. The current investigation focused on the influence of testing with feedback on fifth graders’ learning of science concepts. Across two experiments, 65 students studied twenty key concept definitions. After study, the definitions were randomly assigned to one of four conditions: control, test only, study only, and test plus feedback. Concepts assigned to the latter three conditions were presented again (either for test only, study only, or test plus feedback) during two separate sessions, and a final test was administered during a separate session. At the final test, students were asked to provide the definition for each of the twenty key concepts. Final test performance was best for definitions that had been tested with feedback, followed by recall for those that had only been tested or only restudied, with lowest performance for those that did not receive additional practice. Despite multiple sessions spaced across several days, however, performance for all conditions was low, which may have resulted from the ineffective use of feedback. In summary, testing followed by feedback can boost younger students learning of science concepts, but mastery will require the use of other strategies as well.  相似文献   
147.
Observers viewed modified launching effect displays containing a spatial gap between the final location of the launcher (a black square) and the initial location of the target (a black outline square with a white interior). In some conditions, a set of stationary objects (black outline squares with white interiors) filled the spatial gap, and these objects began changing colour upon contact from the launcher. The colour changes could involve all gap objects turning black, the first gap object turning dark grey and subsequent gap objects turning successively lighter grey, or first gap object turning light grey and subsequent gap objects turning successively darker grey. The colour changes could move from the launcher to the target or from the target to the launcher. The gap objects could also remain unchanged. Participants rated whether the launcher caused subsequent motion of the target and how much force the launcher imparted to the target. The sequence of colour changes, and the sequence of locations in which colour changes occurred, influenced ratings; sequences of colour changes consistent with the idea that influence of the launcher was transmitted across gap objects to the target resulted in higher ratings. Implications for visual perception of causality are discussed.  相似文献   
148.
A portfolio forecasting model based on particle swarm optimization (PSO) algorithm with automatic factor scaling is proposed in this Article to effectively improve the accuracy of related analysis model in portfolio application. Firstly, the portfolio problem is analyzed and a hybrid constraint portfolio model is obtained by improving portfolio model with consideration of general portfolio model and combination of market value constraint and upper bound constraint according to Markowitz's theory. Secondly, PSO algorithm is introduced during analysis on portfolio model and solution is found with the hybrid constraint portfolio model of PSO on portfolio. In addition, in order to further improve the performance of PSO in model solution, automatic factor scaling is used for adaptive learning on parameters associated with PSO, to improve convergence of the algorithm. At last, simulation experiments show that the algorithm proposed can obtain a more ideal investment portfolio scheme, thereby reducing investment risks and obtaining greater investment returns.  相似文献   
149.
把手放在刺激旁边,会对知觉、记忆、语义和执行控制等认知加工产生影响,这类现象被称为手近效应。手近效应反映了身体与环境的互动对认知的塑造作用,为具身认知提供了新证据。本文从手近效应的内容,影响因素,及其认知、神经机制等方面对相关研究进行梳理。并从手近效应的神经机制,应用研究,以及动作意图和人际社会因素的调节作用等方面探讨当前手近效应还未解决的问题。  相似文献   
150.
陈睿  杨景  何顺超  李鹏 《心理科学》2018,(2):318-323
刺激的情绪性具有增强记忆的效果,那么,带有情绪信息的刺激对遗忘又会产生怎样的影响?已有研究从行为及认知神经机制层面探讨了情绪性刺激对定向遗忘效应的影响,但结果并不一致。总结已有文献发现,以情绪性刺激的材料类型、情绪效价、唤醒度和熟悉度为主的客观因素和以被试的情绪状态为主的主观因素均为影响定向遗忘效应产生及其稳定性的重要原因。这类研究是对有意遗忘研究领域的重要补充,也加深了人们对有意遗忘机制的理解。  相似文献   
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