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931.
为了考察不同数学能力水平儿童的执行功能差异,根据331名学前儿童的数学能力得分选取了潜在数学学习困难儿童组、低分组、典型发展儿童组和数学优秀组等4个实验组。首先分析了各组儿童的执行功能差异特点,之后使用判别分析进一步探索了各执行功能子结构对儿童早期数学能力差异分组的贡献。结果表明:相对于典型发展儿童组,潜在数学学习困难儿童在执行功能的更新、抑制和转换方面普遍缺损;低分组儿童则仅表现出数字更新能力不足;数学优秀组在数字更新和有时间要求的认知转换方面比典型发展组有明显优势。进一步判别分析表明,对早期数学能力差异分组贡献最大的并非独立执行功能子结构,而是更新和转换的共同因素结构。  相似文献   
932.
This paper focuses on evidence for mindfulness meditation-related benefits to executive functioning, processes important for much of human volitional behaviour. Miyake et al. (2000) have shown that executive functions can be fractionated into three distinct domains including inhibition, working memory updating, and mental set shifting. Considering these separable domains, it is important to determine whether the effects of mindfulness can generalize to all three sub-functions or are specific to certain domains. To address this, the current review applied Miyake et al.’s (2000) fractionated model of executive functioning to the mindfulness literature. Empirical studies assessing the benefits of mindfulness to measures tapping the inhibition, updating, and shifting components of executive functioning were examined. Results suggest a relatively specific as opposed to general benefit resulting from mindfulness, with consistent inhibitory improvement, but more variable advantages to the updating and shifting domains. Recommendations surrounding application of mindfulness practice and future research are discussed.  相似文献   
933.
An estimated 65% of individuals demonstrate multidomain cognitive impairment poststroke, although little is known about the varying role of cognitive risk and protective factors in preischemic, peri-ischemic, and postischemic stroke phases. Longitudinal changes in global cognitive function after ischemic stroke are not well characterized, especially in older adults over age 80. We examined global cognitive function trajectories in these three phases across a mean follow-up of 8.12 (2.30) years in 159 female stroke survivors aged 65–79 at baseline using linear mixed models with change points. In separate models controlling for demographic variables, we tested the interaction of baseline risk and protective factors with stroke phase on global cognitive function. None of the prestroke global cognitive function means or trajectories differed significantly. At the time of ischemic stroke, higher body mass index (BMI), the presence of hypertension (HTN), low optimism, and higher physical function were all associated with significantly greater mean decreases in global cognition (all p’s <.0.0001), but were not significantly different from the contrasting level (all p’s >0.05). Higher BMI, the presence of HTN, low optimism, and higher physical function were in turn protective of global cognitive decline postischemic stroke (all contrasting p values <.01). Baseline factors may play either a risk or a protective role in global cognitive function depending on the phase of ischemic stroke.  相似文献   
934.
935.
Using an empirically-based simulation study, we show that typically used methods of choosing an item calibration sample have significant impacts on achievement bias and system rankings. We examine whether recent PISA accommodations, especially for lower performing participants, can mitigate some of this bias. Our findings indicate that standard operational methods, while not ideal, recover underlying proficiency reasonably well and generally outperform methods that more completely include all participants. Translating results onto the PISA scale, the calibration sample can induce bias of up to 12.49 points, which is important given that standard errors are around three points. Although ranking correlations are at least.95, we note the policy implications of slight ranking changes. Our findings indicate that limited accommodations targeted at low achieving educational systems do not outperform either of the other methods considered. Research that further explores accommodations for heterogeneous populations is recommended.  相似文献   
936.
It is nearly 35 years since I gave the 7th Sir Frederick Bartlett lecture at Oxford University. This was published as a paper entitled “Orienting of attention in the quarterly journal”. The topic was then primarily in psychology, but now equally often in neuroscience. This paper summarizes the background of the reaction time methods used in the original paper and findings that emerged later on the sensory consequences of orienting, mainly in the visual system. It then discusses the brain network that is the source of the sensory amplification and other brain networks that are involved in attention. Next, it reviews studies of the development of attentional networks in early life. Finally, it indicates how the new tools available to explore the human brain can lead to further progress.  相似文献   
937.
There has recently been much interest in computerized adaptive testing (CAT) for cognitive diagnosis. While there exist various item selection criteria and different asymptotically optimal designs, these are mostly constructed based on the asymptotic theory assuming the test length goes to infinity. In practice, with limited test lengths, the desired asymptotic optimality may not always apply, and there are few studies in the literature concerning the optimal design of finite items. Related questions, such as how many items we need in order to be able to identify the attribute pattern of an examinee and what types of initial items provide the optimal classification results, are still open. This paper aims to answer these questions by providing non‐asymptotic theory of the optimal selection of initial items in cognitive diagnostic CAT. In particular, for the optimal design, we provide necessary and sufficient conditions for the Q ‐matrix structure of the initial items. The theoretical development is suitable for a general family of cognitive diagnostic models. The results not only provide a guideline for the design of optimal item selection procedures, but also may be applied to guide item bank construction.  相似文献   
938.
We investigated the navigation‐related age effects on learning, proactive interference semantic clustering, recognition hits, and false recognitions in a naturalistic situation using a virtual apartment‐based task. We also examined the neuropsychological correlates (executive functioning [EF] and episodic memory) of navigation‐related age effects on memory. Younger and older adults either actively navigated or passively followed the computer‐guided tour of an apartment. The results indicated that active navigation increased recognition hits compared with passive navigation, but it did not influence other memory measures (learning, proactive interference, and semantic clustering) to a similar extent in either age group. Furthermore, active navigation helped to reduce false recognitions in younger adults but increased those made by older adults. This differential effect of active navigation for younger and older adults was accounted for by EF score. Like for the subject‐performed task effects, the effects from the navigation manipulation were well accounted for by item‐specific/relational processing distinction, and they were also consistent with a source monitoring deficit in older adults.  相似文献   
939.
Top-down attentional settings can persist between two unrelated tasks, influencing visual attention and performance. This study investigated whether top-down contextual information in a second task could moderate this “attentional inertia” effect. Forty participants searched through letter strings arranged horizontally, vertically, or randomly and then made a judgement about road, nature, or fractal images. Eye movements were recorded to the picture search and findings showed greater horizontal search in the pictures following horizontal letter strings and narrower horizontal search following vertical letter strings, but only in the first 1000 ms. This shows a brief persistence of attentional settings, consistent with past findings. Crucially, attentional inertia did not vary according to image type. This indicates that top-down contextual biases within a scene have limited impact on the persistence of previously relevant, but now irrelevant, attentional settings.  相似文献   
940.
Conditional multi‐item promotions are a prevalent marketing tactic whereby consumers have to buy a certain number of products to get a discount. This paper examines how framing a multi‐item promotion in terms of savings on multiple items versus a single item (e.g., “buy two, get X% off on both” vs. “buy two, get 2X% off on the cheaper item”) affects consumers’ decision‐making and product choices. Two laboratory studies and a field study at a boutique clothing store demonstrate that the “2X% on cheaper” framing makes consumers more likely to select similarly priced primary and secondary items. This strategy is driven by increased focus on promotional savings under the “2X% on cheaper” framing, which leads consumers to spend more on their secondary items. Overall, this research shows how a subtle change in the framing of multi‐item promotions changes consumers’ product selection strategies and shopping basket composition.  相似文献   
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