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141.
The adult human brain quickly adapts to regular temporal sequences, and emits a sequence of novelty responses when these regularities are violated. These novelty responses have been interpreted as error signals that reflect the difference between the incoming signal and predictions generated at multiple cortical levels. Do infants already possess such a hierarchy of violation-detection mechanisms? Using high-density recordings of event-related potentials during an auditory local–global violation paradigm, we show that three-month-old infants process novelty in temporal sequences at two distinct levels. Violations of local expectancies, such as perceiving a deviant vowel “a” after repeated presentation of another vowel i-i-i, elicited an early auditory mismatch response. Conversely, violations of global expectancies, such as hearing the rare sequence a-a-a-a instead of the frequent sequence a-a-a-i, modulated this early mismatch response and led to a late frontal negative slow wave, whose cortical sources included the left inferior frontal region. These results suggest that the infant brain already possesses two dissociable systems for temporal sequence learning.  相似文献   
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The multisensory response enhancement (MRE), occurring when the response to a visual target integrated with a spatially congruent sound is stronger than the response to the visual target alone, is believed to be mediated by the superior colliculus (SC) (Stein & Meredith, 1993). Here, we used a focused attention paradigm to show that the spatial congruency effect occurs with red (SC-effective) but not blue (SC-ineffective) visual stimuli, when presented with spatially congruent sounds. To isolate the chromatic component of SC-ineffective targets and to demonstrate the selectivity of the spatial congruency effect we used the random luminance modulation technique (Experiment 1) and the tritanopic technique (Experiment 2). Our results indicate that the spatial congruency effect does not require the distribution of attention over different sensory modalities and provide correlational evidence that the SC mediates the effect.  相似文献   
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The objective of this study was to extend the probability of treatment benefit method by adding treatment condition as a stratifying variable, and illustrate this extension of the methodology using the Child and Adolescent Anxiety Multimodal Study data. The probability of treatment benefit method produces a simple and practical way to predict individualized treatment benefit based on pretreatment patient characteristics. Two pretreatment patient characteristics were selected in the production of the probability of treatment benefit charts: baseline anxiety severity, measured by the Pediatric Anxiety Rating Scale, and treatment condition (cognitive-behavioral therapy, sertraline, their combination, and placebo). We produced two charts as exemplars which provide individualized and probabilistic information for treatment response and outcome to treatments for child anxiety. We discuss the implications of the use of the probability of treatment benefit method, particularly with regard to patient-centered outcomes and individualized decision-making in psychology and psychiatry.  相似文献   
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To create customer-oriented organizations, managers are often asked to promote a values-based vision. Yet, many managers struggle with transferring their values to employees making strategic value changes difficult. Despite this challenge, research has yet to demonstrate how managers effectively align values within the sales force, or the impact alignment has on job outcomes. Therefore, we develop and empirically test a conceptual framework to examine the role of transformational leadership in aligning salesperson customer orientation (CO) values. We find that transformational leadership is a strong mechanism in creating perceived value congruence, yet may have a surprising dark side. Results suggest that transformational managers achieve congruence by raising or, contrary to conventional wisdom, lowering salesperson CO values to meet the perceived values of the manager. Response surface modelling results support the importance of perceived manager values. Customer-oriented salespeople have higher job satisfaction and sales performance when they perceive their manager to also have high CO. When values are misaligned, job satisfaction increases more for low CO salespeople as perceptions of manager CO increase. Exploratory findings show that performance was higher under situations of perfect alignment but also under severe misalignment suggesting that values generate performance under complementary or supplementary conditions.  相似文献   
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脓毒症多呈现典型的促炎效应和抗炎反应,并与获得性免疫功能障碍同时出现,且免疫细胞中超过80%的基因表达发生改变。由于单核/巨噬细胞细胞因子谱的改变、主要组织相容性复合体Ⅱ类抗原(MHCⅡ)及共刺激分子表达下降以及树突状细胞的凋亡,诱发细胞免疫功能下降;中性粒细胞活性降低和补体系统的激活,又增加感染易感性。T淋巴细胞表现...  相似文献   
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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   
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Strong associations between target stimuli and responses usually facilitate fast and effortless reactions. The present study investigated whether long-term associations between distractor stimuli and responses modulate behavior. In particular, distractor stimuli can affect behavior due to distractor-based stimulus-response retrieval, a phenomenon called distractor-response binding: An ignored stimulus becomes temporarily associated with a response and retrieves it at stimulus repetition. In a flanker task, participants ignored left and right pointing arrows and responded to a target letter either with left and right (strongly associated) responses or with upper and lower (weakly associated) responses. Binding effects were modulated in dependence of the long-term association strength between distractors and responses. If the association was strong (arrows pointing left and right with left and right responses), binding effects emerged but only in case of compatible responses. If the long-term association between distractors and responses was weak (arrows pointing left and right with upper and lower responses), binding was weaker and not modulated by compatibility. In contrast, sequential compatibility effects were not modulated by association strength between distractor and response. The results indicate that existing long-term associations between stimuli responses may modulate the impact of an ignored stimulus on action control.  相似文献   
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