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41.
《Social neuroscience》2013,8(2):123-138
This fMRI study analyzes inferences on other persons' traits, whereby half of the participants were given spontaneous (“read”) instructions while the other half were given intentional (“infer the person's trait”) instructions. Several sentences described the behavior of a target person from which a strong trait could be inferred (trait diagnostic) or not (trait nondiagnostic). A direct contrast between spontaneous and intentional instructions revealed no significant differences, indicating that the same social mentalizing network was recruited. There was, however, a difference with respect to different brain areas that passed the significance threshold, suggesting that this common network was recruited to a different degree. Specifically, spontaneous inferences significantly recruited only core mentalizing areas, including the temporo-parietal junction and medial prefrontal cortex, whereas intentional inferences additionally recruited other brain areas, including the (pre)cuneus, superior temporal sulcus, temporal poles, and parts of the premotor and parietal cortex. These results suggest that intentional instructions invite observers to think more about the material they read, and consider it in many ways besides its social impact. Future research on the neurological underpinnings of trait inference might profit from the use of spontaneous instructions to get purer results that involve only the core brain areas in social judgment.  相似文献   
42.
《Social neuroscience》2013,8(6):544-554
Joint attention (JA) is a cornerstone of adaptive human social functioning. Little functional magnetic resonance imaging (fMRI) research has examined, in interactive paradigms, neural activation underlying bids for JA, met with a congruent or an incongruent social response. We developed a highly naturalistic fMRI paradigm utilizing eye-tracking to create real-time, contingent social responses to participant-initiated JA. During congruent responses to JA bids, we observed increased activation in the right amygdala, the right fusiform gyrus, anterior and dorsal anterior cingulate cortices, striatum, ventral tegmental area, and posterior parietal cortices. Incongruent responses to JA bids elicited increased activity localized to the right temporoparietal junction (TPJ) and bilateral cerebellum. No differences in eye-gaze patterns were observed during congruent or incongruent trials. Our results highlight the importance of utilizing interactive fMRI paradigms in social neuroscience and the impact of congruency in recruiting integrated social, reward, and attention circuits for processing JA.  相似文献   
43.
ObjectiveExposure to childhood trauma (CT) is associated with cognitive impairment in schizophrenia, and deficits in social cognition in particular. Here, we sought to test whether IL-6 mediated the association between CT and social cognition both directly, and sequentially via altered default mode network (DMN) connectivity.MethodsThree-hundred-and-eleven participants (104 patients and 207 healthy participants) were included, with MRI data acquired in a subset of n = 147. CT was measured using the childhood trauma questionnaire (CTQ). IL-6 was measured in both plasma and in toll like receptor (TLR) stimulated whole blood. The CANTAB emotion recognition task (ERT) was administered to assess social cognition, and cortical connectivity was assessed based on resting DMN connectivity.ResultsHigher IL-6 levels, measured both in plasma and in toll-like receptor (TLR-2) stimulated blood, were significantly correlated with higher CTQ scores and lower cognitive and social cognitive function. Plasma IL-6 was further observed to partly mediate the association between higher CT scores and lower emotion recognition performance (CTQ total: βindirect −0.0234, 95% CI: −0.0573 to −0.0074; CTQ physical neglect: βindirect = −0.0316, 95% CI: −0.0741 to −0.0049). Finally, sequential mediation was observed between plasma IL-6 levels and DMN connectivity in mediating the effects of higher CTQ on lower social cognitive function (βindirect = −0.0618, 95% CI: −0.1523 to −0.285).ConclusionThis work suggests that previous associations between CT and social cognition may be partly mediated via an increased inflammatory response. IL-6′s association with changes in DMN activity further suggest at least one cortical network via which CT related effects on cognition may be transmitted.  相似文献   
44.
45.
Activity within the visual cortex can be influenced by the emotional salience of a stimulus, but it is not clear whether such cortical activity is modulated by the affective status of the individual. This study used functional magnetic resonance imaging (fMRI) to examine the relationship between affect ratings on the Positive and Negative Affect Schedule and activity within the occipital cortex of 13 normal-weight women while viewing images of high calorie and low calorie foods. Regression analyses revealed that when participants viewed high calorie foods, Positive Affect correlated significantly with activity within the lingual gyrus and calcarine cortex, whereas Negative Affect was unrelated to visual cortex activity. In contrast, during presentations of low calorie foods, affect ratings, regardless of valence, were unrelated to occipital cortex activity. These findings suggest a mechanism whereby positive affective state may affect the early stages of sensory processing, possibly influencing subsequent perceptual experience of a stimulus.  相似文献   
46.
The aim of this study was to investigate the influence of short-term repetitive electrical stimulation (rES training session) on the motor-evoked hemodynamic responses. The fMRI echo-planar images (EPI) were recorded before and after the rES training. The right median nerve (MN) was stimulated during rES. The rES training resulted in a significant increase in activity in a number of supraspinal regions, including sensorimotor and associative cortical areas. On the subcortical level, the effect was also found in the cerebellum, the midbrain, and the thalamus. Possible mechanisms of the neuronal plastic changes observed after rES, and memory processes involved in learning are discussed.  相似文献   
47.
This systematic review aimed to provide a comprehensive summary of the current literature on the neurobiological underpinnings of the experience of the negative moral emotions: shame, embarrassment and guilt. PsycINFO, PubMed and MEDLINE were used to identify existing studies. Twenty-one functional and structural magnetic resonance imaging and positron emission tomography studies were reviewed. Although studies differed considerably in methodology, their findings highlight both shared and distinct patterns of brain structure/function associated with these emotions. Shame was more likely to be associated with activity in the dorsolateral prefrontal cortex, posterior cingulate cortex and sensorimotor cortex; embarrassment was more likely to be associated with activity in the ventrolateral prefrontal cortex and amygdala; guilt was more likely to be associated with activity in ventral anterior cingulate cortex, posterior temporal regions and the precuneus. Although results point to some common and some distinct neural underpinnings of these emotions, further research is required to replicate findings.  相似文献   
48.
The posterior midline region (PMR)—considered a core of the default mode network—is deactivated during successful performance in different cognitive tasks. The extent of PMR‐deactivations is correlated with task‐demands and associated with successful performance in various cognitive domains. In the domain of episodic memory, functional MRI (fMRI) studies found that PMR‐deactivations reliably predict learning (successful encoding). Yet it is unclear what explains this relation. One intriguing possibility is that PMR‐deactivations are partially mediated by respiratory artifacts. There is evidence that the fMRI signal in PMR is particularly prone to respiratory artifacts, because of its large surrounding blood vessels. As respiratory fluctuations have been shown to track changes in attention, it is critical for the general interpretation of fMRI results to clarify the relation between respiratory fluctuations, cognitive performance, and fMRI signal. Here, we investigated this issue by measuring respiration during word encoding, together with a breath‐holding condition during fMRI‐scanning. Stimulus‐locked respiratory analyses showed that respiratory fluctuations predicted successful encoding via a respiratory phase‐locking mechanism. At the same time, the fMRI analyses showed that PMR‐deactivations associated with learning were reduced during breath‐holding and correlated with individual differences in the respiratory phase‐locking effect during normal breathing. A left frontal region—used as a control region—did not show these effects. These findings indicate that respiration is a critical factor in explaining the link between PMR‐deactivation and successful cognitive performance. Further research is necessary to demonstrate whether our findings are restricted to episodic memory encoding, or also extend to other cognitive domains. Hum Brain Mapp 35:4932–4943, 2014. © 2014  相似文献   
49.
The aim of this study was to determine the brain regions associated with suppressing the image of an object. We used functional magnetic resonance imaging (fMRI) during five mental tasks (imagining, suppressing, erasing, free thinking and resting) performed by the subjects. The analysis showed that the suppressing, erasing and imagining conditions all activated the parietal and prefrontal regions to a different extent. These results suggest that the regions associated with cognitive control were also activated while a simple mental process was performed. Additionally, the results showed that the parietal lobe is the key region for the suppression of a mental image.  相似文献   
50.
Abstract

Therapeutic neuroscience education (TNE) has been shown to be effective in the treatment of mainly chronic musculoskeletal pain conditions. This case study aims to describe the changes in brain activation on functional magnetic resonance imaging (fMRI) scanning, before and after the application of a newly-designed preoperative TNE program. A 30-year-old female with a current acute episode of low back pain (LBP) and radiculopathy participated in a single preoperative TNE session. She completed pre- and post-education measures including visual analog scale (VAS) for LBP and leg pain; Oswestry Disability Index (ODI); Fear Avoidance Beliefs Questionnaire (FABQ); Pain Catastrophizing Scale (PCS) and a series of Likert-scale questions regarding beliefs and attitudes to lumbar surgery (LS). After a 30-minute TNE session, ODI decreased by 10%, PCS decreased by 10 points and her beliefs and attitudes shifted positively regarding LS. Immediately following TNE straight leg raise increased by 7° and forward flexion by 8?cm. fMRI testing following TNE revealed 3 marked differences compared to pre-education scanning: (1) deactivation of the periaqueductal gray area; (2) deactivation of the cerebellum; and (3) increased activation of the motor cortex. The immediate positive fMRI, psychometric and physical movement changes may indicate a cortical mechanism of TNE for patients scheduled for LS.  相似文献   
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