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51.
Working memory (WkM) is a fundamental cognitive process that serves as a building block for higher order cognitive functions. While studies have shown that children and adolescents utilize similar brain regions during verbal WkM, there have been few studies that evaluate the developmental differences in brain connectivity. Our goal was to study the development of brain connectivity related to verbal WkM in typically developing children and adolescents. Thirty‐five healthy children and adolescents, divided into three groups: 9–12 (children), 13–16 (young adolescents), and 17–19 (older adolescents) years, were included in this functional magnetic resonance imaging (fMRI) study. The verbal WkM task involved a modified Sternberg item recognition paradigm using three different loads. Brain connectivity analysis was performed using independent component analyses and regressing the components with the design matrix to determine task‐related networks. Connectivity analyses resulted in four components associated solely with encoding, four solely with recognition and two with both. Two networks demonstrated age‐related differences with respect to load, (1) the left motor area and right cerebellum, and 2) the left prefrontal cortex, left parietal lobe, and right cerebellum. Post hoc analyses revealed that the first network showed significant effects of age between children and the two older groups. There was increasing connectivity with increasing load for adolescents. The second network demonstrated age‐related differences between children and older adolescents. Children have higher task‐related connectivity at lower loads, but they tend to equalize with the adolescents with higher loads. Finally, a non‐load related network involving the orbital frontal and anterior cingulate cortices showed less connectivity in children. Hum Brain Mapp 35:698–711, 2014. © 2012 Wiley Periodicals, Inc.  相似文献   
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Failure to ensure organizational readiness for curricular integration of simulation can result in a costly and ineffective simulation program. Organizational leaders who are aware of the principles of changemaker leadership and specific operational considerations are best positioned to ensure a quality simulation program. To assist these leaders, this article provides practical information derived from dissection of the Standard of Best Practice: SimulationSM: Operations, including topics of strategic planning, financial resources, expert personnel, resource management systems, policies and procedures, and systems integration. Additionally, an introduction to a foundational tool to spearhead change is offered, and characteristics of the changemaker leader needed to develop and sustain an effective and efficient simulation program are highlighted. Understanding the criteria necessary for effective simulation operations and early recognition of the conditions and variables that can influence organizational culture is of utmost importance to ensure programmatic success.  相似文献   
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Objective. To implement and evaluate an active-learning laboratory activity to teach pharmacy students about influenza, pneumococcal, and shingles vaccines.Design. The laboratory session was divided into 6 immunization stations: 3 stations on influenza including a pediatrics station, and 1 station each for pneumococcal, shingles, and anaphylaxis.Assessment. Although 118 of 123 (95.9%) students had completed an immunization training certificate prior to attending the laboratory, the average score on a pre-assessment to measure immunization knowledge and confidence was 56%. The post-assessment score was 87.4%. Students’ confidence improved by 18.7% to 51.2% in each of the 5 areas assessed. Most respondents rated the activity overall as good or excellent on a post-activity evaluation.Conclusion. An active-learning approach to teaching immunizations allowed students to gain knowledge in simulated real-world experiences and reinforced key concepts on influenza, pneumococcal, and shingles vaccines.  相似文献   
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Early parent–infant home visiting interventions have been found to be effective in both developed and developing countries. However, there is a need to build an evidence base for these interventions in the South African context, to inform local early childhood development policy. The Ububele Mother-Baby Home Visiting Programme in Alexandra, Johannesburg, combines a psychoanalytic approach to thinking about parent–infant relationships and local infant care knowledge. Trained, local women offer a 14-visit intervention, which aims to support mothers, increase knowledge about the relational needs of infants, and increase maternal reflective function capacities. A mixed-methods approach was used to evaluate preliminary findings regarding mothers' responses to the programme and found significant increases in the mothers’ levels of perceived support, in levels of knowledge regarding the relational needs of infants and in maternal reflective function capacities. The supportive relationship between home visitors and mothers was highlighted as key to programme success.  相似文献   
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Sleep is an important health risk factor. In the context of pediatric chronic pain, sleep is often impaired and temporal daily associations link sleep deficiency to subsequent increased pain. It is unknown whether similar temporal relationships exist for youth with acute pain. Thus, we characterized sleep in youth with acute musculoskeletal (MSK) pain to examine daily sleep-pain associations. Participants were 67 youth (10–17 years) with acute MSK pain (<1 month duration). Youth underwent eight nights of actigraphic sleep monitoring and completed twice daily pain diaries. Generalized linear models tested nighttime sleep as a predictor of morning pain, and evening pain as a predictor of nighttime sleep. Shorter sleep duration and poorer sleep quality predicted higher morning pain intensity. However, evening pain did not predict nighttime sleep, suggesting the strongest temporal association is in the direction of sleep deficiency impacting next-day pain, as has been found in prior research in youth with chronic pain.  相似文献   
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Purpose: Understanding the causes of fertilization failure is an important research field in assisted reproductive programs. The present study aimed to evaluated the possible relationship between chromatin packaging quality (CMA3 staining) and (i) normal morphology and (ii) its ability to predict the functional integrity of spermatozoa in both in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) treatment programs. Methods: Semen of 140 men from IVF and ICSI couples were analyzed for sperm concentration, motility, morphology, and chromatin packaging (CMA3). For CMA3 classification, two cutoff values were used, namely, 44.5%±13 and 1 SD above the mean, i.e., 57.5% (rounded off to 60%). IVF and ICSI data were stratified using three basic cutoff values for CMA3 staining, namely, <44%, >44–60%, and >60%. Results: Based on CMA3 results patients were divided into four groups, namely, group A, <44% CMA3 (n = 15, IVF); group B, 44% and <60% CMA3 (n = 39, IVF); group C, 60% CMA3 (n = 45 IVF); and group D, 60% CMA3(n = 41 ICSI). During receiver operator characteristic analyses the estimated cutoff value for CMA3 staining, to distinguish between <4% and 4% morphology groups, was 60%. The area under the curve was 0.89, sensitivity of 75%, and specificity of 100%. When IVF rates of >60% and <60% were used, the optimal CMA3 value for prediction of fertilization success again was recorded at 60%. The area under the curve was 0.76, sensitivity of 81.5%, and specificity of 63.6%. Conclusions: Chromatin packaging assessments should be included as a complementary assay to the sequential diagnostic approach of the male-factor patients.  相似文献   
60.
We extend our findings showing dose-dependent cocaine inhibition of differentiation in NGF-stimulated PC-12 cells without affecting cell viability by demonstrating that neurite extension is severely limited after 24 h, maximal effect is reached at 36 h and recovery is only partial. Cocaine metabolites lack these effects. A similar process may occur following human prenatal exposure, perhaps through cocaine-induced changes in gene expression or other intracellular signalling events.  相似文献   
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