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11.
《Vaccine》2021,39(17):2434-2444
BackgroundAchieving universal immunization coverage and reaching every child with life-saving vaccines will require the implementation of pro-equity immunization strategies, especially in poorer countries. Gavi-supported countries continue to implement and report strategies that aim to address implementation challenges and improve equity. This paper summarizes the first mapping of these strategies from country reports.MethodsThirteen Gavi-supported countries were purposively selected with emphasis on Gavi’s priority countries. Following a scoping of different documents submitted to Gavi by countries, 47 Gavi Joint Appraisals (JAs) for the period 2016–2019 from the 13 selected countries were included in the mapping. We used a consolidated framework synthesized from 16 different equity and health systems frameworks, which incorporated UNICEF’s coverage and equity assessment approach – an adaptation of the Tanahashi model. Using search terms, the mapping was conducted using a combination of manual search and the MAXQDA qualitative analysis tool. Pro-equity strategies meeting the inclusion criteria were identified and compiled in an Excel database, and then populated on a tableau visualization dashboard.ResultsIn total, 258 pro-equity strategies were implemented by the 13 sampled Gavi-supported countries between 2016 and 2019. The framework determinants of social norms, utilization, and management and coordination accounted for more than three-quarters of all pro-equity strategies implemented in these countries. The median number of strategies reported per country was 17. Afghanistan, Nigeria, and Uganda reported the highest number of strategies that we considered as pro-equity.ConclusionFindings from this mapping can be useful in addressing equity gaps, reaching partially immunized, and ‘zero-dose’ vaccinated children, and valuable resource for countries planning to implement pro-equity strategies, especially as immunization stakeholders reimagine immunization delivery in light of COVID-19, and as Gavi finalizes its fifth organizational strategy. Future efforts should seek to identify pro-equity strategies being implemented across additional countries, and to assess the extent to which these strategies have improved immunization coverage and equity.  相似文献   
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中药质量的评控问题是制约中药现代化发展的瓶颈,因此有必要在现有检测方法的基础上结合生物评价,继而更为全面地保证中药质量。生物评价是完善中药质量标准、保证临床功效和安全性评价的重要方法,已成为中药质量标准化发展趋势之一。在此处主要论述了近年来基于生物活性与效应基准的中药质量评价技术和已取得的部分研究进展,同时对目前中药质量生物评价研究与应用中存在的主要问题进行探讨,进一步对其未来应用做出展望,从而更好的对中药质量进行控制。  相似文献   
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受体酪氨酸激酶(RTKs)是一种主要的膜受体,调控细胞增殖、分化和迁移。解除RTK信号通路的管制会导致许多疾病,如癌症和发育障碍。促红细胞生成素肝细胞受体(Erythropoietin-producing hepatocellular,Eph)家族是酪氨酸激酶受体家族中最大的一个亚族,其与配体Ephrin的相互作用在生长发育和肿瘤发生过程中发挥着重要作用。研究表明,一种缺乏酪氨酸激酶活性的特殊Eph受体EphB6在乳腺癌、结直肠癌等许多恶性肿瘤中表达下降,而大量证据表明EphB6表达的缺失依赖于其启动子DNA的高甲基化,进而促进肿瘤的进展与转移。EphB6是近期研究的热点因子,本文就其目前在恶性肿瘤中研究进展做一综述。  相似文献   
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《L'Encéphale》2020,46(2):146-152
Tourette syndrome is a neurodevelopmental disorder which is characterized by the presence of motor and phonic tics. These tics are generally more prevalent in childhood. Tics typically reach their maximum severity before puberty, around age 10 to 12. In most patients, tic severity usually decreases during late adolescence and adulthood. However, this is not true for all individuals. To date, the developmental trajectory leading to the persistence of tics into adulthood is still poorly understood. There are very few markers that can predict the evolution of tic symptoms from childhood to adulthood. Yet, while we cannot cure Tourette syndrome, it is possible to reduce tic severity with various treatments. The most common treatments are pharmacotherapy and behavioral and cognitive-behavioral therapy. However, there appears to be a limit to the proportion of tics that can be treated, since most treatments offer an average reduction in tics of no more than 50%. Thus, at first, this article reviews recent advances in treatment and symptom progression. Next, we propose some lines of research to improve the management and treatment of people with Tourette syndrome.  相似文献   
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《Vaccine》2020,38(44):6941-6953
Addressing vaccine management bottlenecks, including high vaccine wastage rates, has traditionally been addressed through health worker training and other didactic methods of technical assistance or support as required. It has been shown, though, that the high level of technical skills, expertise, and responsibility required in vaccine handling and management cannot be achieved by mere didactic learning. While gains have been made in vaccine management and handling with these approaches, there remain challenges of high vaccine wastage rates and poor vaccine management practices across the board. Interestingly, approaching vaccine management through social behavior change has not been documented. Through Participatory Action Research (PAR), which is increasingly being used in health sciences, we explore an attempt at strengthening vaccine management and thus reducing high vaccine wastage rates by working together with health workers to identify plausible, realistic solutions to vaccine management through social behavior change. Select health workers directly involved with the immunization program in the four major provinces of the Solomon Islands were identified purposively to use action media and come up with concepts and materials for social behavior change communication that will have an impact on effective vaccine management and reducing wastages. This is the first documented use of such methodology in addressing vaccine management issues.  相似文献   
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《Brain stimulation》2020,13(6):1535-1547
BackgroundHippocampal oscillations play a critical role in the ontogeny of allocentric memory in rodents. During the critical period for memory development, hippocampal theta is the driving force behind the temporal coordination of neuronal ensembles underpinning spatial memory. While known that hippocampal oscillations are necessary for normal spatial cognition, whether disrupted hippocampal oscillatory activity during the critical period impairs long-term spatial memory is unknown. Here we investigated whether disruption of normal hippocampal rhythms during the critical period have enduring effects on allocentric memory in rodents.Objective/hypothesisWe hypothesized that disruption of hippocampal oscillations via artificial regulation of the medial septum during the critical period for memory development results in long-standing deficits in spatial cognition.MethodsAfter demonstrating that pan-neuronal medial septum (MS) optogenetic stimulation (465 nm activated) regulated hippocampal oscillations in weanling rats we used a random pattern of stimulation frequencies to disrupt hippocampal theta rhythms for either 1Hr or 5hr a day between postnatal (P) days 21–25. Non-stimulated and yellow light-stimulated (590 nm) rats served as controls. At P50-60 all rats were tested for spatial cognition in the active avoidance task. Rats were then sacrificed, and the MS and hippocampus assessed for cell loss. Power spectrum density of the MS and hippocampus, coherences and voltage correlations between MS and hippocampus were evaluated at baseline for a range of stimulation frequencies from 0.5 to 110 Hz and during disruptive hippocampal stimulation. Unpaired t-tests and ANOVA were used to compare oscillatory parameters, behavior and cell density in all animals.ResultsNon-selective optogenetic stimulation of the MS in P21 rats resulted in precise regulation of hippocampal oscillations with 1:1 entrainment between stimulation frequency (0.5–110 Hz) and hippocampal local field potentials. Across bandwidths MS stimulation increased power, coherence and voltage correlation at all frequencies whereas the disruptive stimulation increased power and reduced coherence and voltage correlations with most statistical measures highly significant (p < 0.001, following correction for false detection). Rats receiving disruptive hippocampal stimulation during the critical period for memory development for either 1Hr or 5hr had marked impairment in spatial learning as measured in active avoidance test compared to non-stimulated or yellow light-control rats (p < 0.001). No cell loss was measured between the blue-stimulated and non-stimulated or yellow light-stimulated controls in either the MS or hippocampus.ConclusionThe results demonstrated that robust regulation of hippocampal oscillations can be achieved with non-selective optogenetic stimulation of the MS in rat pups. A disruptive hippocampal stimulation protocol, which markedly increases power and reduces coherence and voltage correlations between the MS and hippocampus during the critical period of memory development, results in long-standing spatial cognitive deficits. This spatial cognitive impairment is not a result of optogenetic stimulation-induced cell loss.  相似文献   
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Influential investigations of postmortem human brain tissue showed regional differences in tissue properties at early phases of development, such as between prefrontal and primary sensory cortical regions. Large-scale neuroimaging studies enable characterization of age-related trajectories with much denser sampling of cortical regions, assessment ages, and demographic variables than postmortem tissue analyses, but no single imaging measure perfectly captures what is measured with histology. Using publicly available data from the Pediatric Imaging, Neurocognition, and Genetics (PING) study, including 951 participants with ages ranging from 3 to 21 years, we characterized cortical regional variability in developmental trajectories of multimodal brain imaging measures. Multivariate analyses integrated morphometric and microstructural cortical surface measures. To replicate foundational histological work showing delayed synapse elimination in middle frontal gyrus relative to primary sensory areas, we tested whether developmental trajectories differ between prefrontal and visual or auditory cortex. We extended this to a whole-cortex analysis of interregional differences, producing cortical parcellations with maximally different developmental trajectories. Consistent with the general conclusions of postmortem analyses, our imaging results suggest that prefrontal regions show a protracted period of greater developmental change; however, they also illustrate the challenges of drawing conclusions about the relative maturational phases of different brain regions.  相似文献   
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