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1.
ADHD儿童认知障碍的主要特征之一是执行功能损害,涉及包括前额叶皮层在内的特定脑区域及多层级脑网络异常。执行功能按照功能性分为冷-热两方面:冷执行功能损害主要表现于反应抑制、工作记忆以及认知灵活性等;热执行功能损害通常涉及延迟满足、赏罚相关决策、自我调节及情绪调节等。ADHD儿童的执行功能评估应基于可信范式进行文化适应性调整。临床干预不能单一聚焦于冷执行功能,需关注儿童的身体发育以及热执行功能(情绪社会方面)的发展进程,结合其他共病与心理状况,进行全面的动态随访与干预,以达到最佳的长期疗效。  相似文献   
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Previous event-related potential (ERP) studies show that a salient lateral sound activates the visual cortex more strongly contralateral to the sound, observed as an auditory-evoked contralateral occipital positivity (ACOP). Studies showed that this activation enhances the early cortical processing of co-localized visual stimuli presented after, reflected by better detection rates, better discrimination, and sharper perceived contrast. We replicated the ACOP, using earphones, and tested whether auditory cuing can influence temporal order judgments (TOJ) for two visual stimuli (horizontal arrangement) as well as if the ACOP would predict the amplitude of this influence. A lateral salient sound was followed, after 150 or 630 ms, by the visual presentation of a pair of disks, one in left and one in right hemifield, with variable SOA. The TOJ task was to indicate which disk appeared first or which disk appeared second (controlling for response bias). We observed an ACOP at posterior electrode sites and confirmed our hypothesis that the lateral sound influenced TOJ by accelerating the perception of the disk presented on the cued side, even though the sound was irrelevant to the task. Furthermore, the ACOP amplitude was correlated to this visual perceptual change, indicating that a larger change in brain activity was associated with a faster processing of co-localized visual stimuli.  相似文献   
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Mind wandering (MW) has become a prominent topic of neuroscientific investigation due to the importance of understanding attentional processes in our day‐to‐day experiences. Emerging evidence suggests a critical role for three large‐scale brain networks in MW: the default network (DN), the central executive network (CEN), and the salience network (SN). Advances in analytical methods for neuroimaging data (i.e., dynamic functional connectivity, DFC) demonstrate that the interactions between these networks are not static but dynamically fluctuate over time (Chang & Glover, 2010, NeuroImage, 50(1), 81–98). While the bulk of the evidence comes from studies involving resting‐state functional MRI, a few studies have investigated DFC during a task. Direct comparison of DFC during rest and task with frequent MW is scarce. The present study applies the DFC method to neuroimaging data collected from 30 participants who completed a resting‐state run followed by two runs of sustained attention to response task (SART) with embedded probes indicating a high prevalence of MW. The analysis identified five DFC states. Differences between rest and task were noted in the frequency of three DFC states. One DFC state characterized by negative DN–CEN/SN connectivity along with positive CEN–SN connectivity was more frequently observed during task vs. rest. Two DFC states, one of which was characterized by weaker connectivity between networks, were more frequently observed during rest than task. These findings suggest that the dynamic relationships between brain networks may vary as a function of whether ongoing cognitive activity unfolds in an “unconstrained” manner during rest or is “constrained” by task demands.  相似文献   
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Hypogonadotrophic hypogonadism (HH) is a rare disorder that manifests absent puberty and infertility. Genetic syndromes with hypogonadism, such as Klinefelter syndrome, are associated with an increased risk of neurodevelopmental disorders (NDDs). However, it is not clear whether patients with HH or transient delayed puberty in general, have an increased risk of NDDs. We performed a register‐based study on a national cohort of 264 patients with HH and 7447 patients diagnosed with delayed puberty that was matched with 2640 and 74 470 controls, respectively. The outcome was defined as having any of the following NDD diagnoses: (i) autism spectrum disorder (ASD); (ii) attention deficit hyperactivity disorder (ADHD); or (iii) intellectual disability (ID). Additional sensitivity analyses were performed to control for different parental and birth variables, as well as diagnosed malformation syndromes and chromosomal anomalies (ie, Down’s and Turner syndromes). Patients with HH had increased risk for being diagnosed with ASD (odds ratio [OR] = 5.7; 95% confidence interval [CI] = 2.6‐12.6), ADHD (OR = 3.0; 95% CI = 1.8‐5.1) and ID (OR = 18.0; 95% CI = 8.9‐36.3) compared to controls. Patients with delayed puberty also had a significantly increased risk of being diagnosed with an NDD. These associations remained significant after adjustments. This is the first study to demonstrate a significant association between HH, delayed puberty and NDDs in a population‐based cohort. Clinicians should be aware of the overlap between these disorders. Further studies should explore the mechanisms behind these associations.  相似文献   
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IntroductionTinnitus is characterized by the presence of a sound in the absence of external sound stimulus. In individuals with normal audiometry, it may be associated with auditory attention difficulty, especially in those who report high tinnitus annoyance.ObjectiveTo investigate auditory attention ability in individuals with tinnitus complaint.MethodsCross-sectional analytical observational study. We evaluated 30 volunteers with normal hearing (up to 25 dBHL): 15 with tinnitus (test group) and 15 with no complaints (control group), aged between 18-40 years. The volunteers answered the tinnitus handicap inventory questionnaire and a visual analogue scale. Subsequently, a basic audiological evaluation (meatoscopy, tonal and vocal audiometry, and imittanciometry) and psychoacoustic measures of tinnitus (loudness and pitch) were performed. To evaluate auditory attention, the following tests were performed: auditory cognitive evoked potential (P300), central auditory processing tests (dichotic digits test and speech-in-noise test) and sustained auditory attention ability test.ResultsIn the tinnitus handicap inventory, individuals with tinnitus had a mean score of 37.78 (±27.05), characterized as moderate degree. In the dichotic digits test (binaural separation), a difference was observed between the groups in both ears. Moreover, there was a difference in the speech-in-noise test in both ears (RE: p = 0.044; LE: p = 0.019), in P300 (p = 0.049) and in total sustained auditory attention ability test (p = 0.032). Also, there is a negative correlation between sustained auditory attention ability test, decrease in attentiveness and binaural integration (RE: p = 0.044; LE: p = 0.048).ConclusionsIndividuals with tinnitus had a poorer performance compared to the control group regarding auditory attention ability. Therefore, it is inferred that tinnitus is associated with poor performance in selective and sustained auditory attention in the assessed volunteers. These aspects should be considered for the management of patients with tinnitus.  相似文献   
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White matter bundles linking gray matter nodes are key anatomical players to fully characterize associations between brain systems and cognitive functions. Here we used a multivariate lesion inference approach grounded in coalitional game theory (multiperturbation Shapley value analysis, MSA) to infer causal contributions of white matter bundles to visuospatial orienting of attention. Our work is based on the characterization of the lesion patterns of 25 right hemisphere stroke patients and the causal analysis of their impact on three neuropsychological tasks: line bisection, letter cancellation, and bells cancellation. We report that, out of the 11 white matter bundles included in our MSA coalitions, the optic radiations, the inferior fronto‐occipital fasciculus and the anterior cingulum were the only tracts to display task‐invariant contributions (positive, positive, and negative, respectively) to the tasks. We also report task‐dependent influences for the branches of the superior longitudinal fasciculus and the posterior cingulum. By extending prior findings to white matter tracts linking key gray matter nodes, we further characterize from a network perspective the anatomical basis of visual and attentional orienting processes. The knowledge about interactions patterns mediated by white matter tracts linking cortical nodes of attention orienting networks, consolidated by further studies, may help develop and customize brain stimulation approaches for the rehabilitation of visuospatial neglect.  相似文献   
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Event‐related potentials (ERPs) are used extensively to investigate the neural mechanisms of attention control and selection. The univariate ERP approach, however, has left important questions inadequately answered. We addressed two questions by applying multivariate pattern classification to multichannel ERPs in two cued visual spatial attention experiments (N = 56): (a) impact of cueing strategies (instructional vs. probabilistic) on attention control and selection and (b) neural and behavioral effects of individual differences. Following cue onset, the decoding accuracy (cue left vs. cue right) began to rise above chance level earlier and remained higher in instructional cueing (~80 ms) than in probabilistic cueing (~160 ms), suggesting that unilateral attention focus leads to earlier and more distinct formation of the attention control set. A similar temporal sequence was also found for target‐related processing (cued target vs. uncued target), suggesting earlier and stronger attention selection under instructional cueing. Across the two experiments: (a) individuals with higher cue‐related decoding accuracy showed higher magnitude of attentional modulation of target‐evoked N1 amplitude, suggesting that better formation of anticipatory attentional state leads to stronger modulation of target processing, and (b) individuals with higher target‐related decoding accuracy showed faster reaction times (or larger cueing effects), suggesting that stronger selection of task‐relevant information leads to better behavioral performance. Taken together, multichannel ERPs combined with machine learning decoding yields new insights into attention control and selection that complement the univariate ERP approach, and along with the univariate ERP approach, provides a more comprehensive methodology to the study of visual spatial attention.  相似文献   
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