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31.
《Biochemical pharmacology》2014,89(4):652-660
Dementia research over the last 50 years has expanded enormously and has greater international interest now than at any time in history. A variety of scientific approaches have been brought to bear on this complex disorder in which the syndrome of clinical features is its defining importance in societal terms. Little has emerged in terms of tangible benefits for people with dementia to date other than a hugely increased awareness at societal and governmental levels. One of the drivers for the increase in focus has been epidemiological evidence, which has provided background numbers for the justification of resources for dementia research. However it can be argued that this justification did not take into account the true meaning of the population evidence, drawing instead on preconceptions which were, at the time, the widely accepted interpretations of earlier evidence. Current evidence, along with the lack of single therapeutic successes, suggests that a clearer analysis is required which not only examines the value and applicability of existing knowledge, most particularly its generation and generalizability, but also where future investment should go for most likely benefit of populations. This includes a hard look at the pre-occupation of societies with single therapies, their place in the context of prevention more generally, particularly within aging populations, and how evidence is generated on likely impacts and their timeframes.  相似文献   
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Excessive ethanol drinking in rodent models may involve activation of the innate immune system, especially toll-like receptor 4 (TLR4) signaling pathways. We used intracellular recording of evoked GABAergic inhibitory postsynaptic potentials (eIPSPs) in central amygdala (CeA) neurons to examine the role of TLR4 activation by lipopolysaccharide (LPS) and deletion of its adapter protein CD14 in acute ethanol effects on the GABAergic system. Ethanol (44, 66 or 100 mM) and LPS (25 and 50 μg/ml) both augmented eIPSPs in CeA of wild type (WT) mice. Ethanol (44 mM) decreased paired-pulse facilitation (PPF), suggesting a presynaptic mechanism of action. Acute LPS (25 μg/ml) had no effect on PPF and significantly increased the mean miniature IPSC amplitude, indicating a postsynaptic mechanism of action. Acute LPS pre-treatment potentiated ethanol (44 mM) effects on eIPSPs in WT mice and restored ethanol’s augmenting effects on the eIPSP amplitude in CD14 knockout (CD14 KO) mice. Both the LPS and ethanol (44–66 mM) augmentation of eIPSPs was diminished significantly in most CeA neurons of CD14 KO mice; however, ethanol at the highest concentration tested (100 mM) still increased eIPSP amplitudes. By contrast, ethanol pre-treatment occluded LPS augmentation of eIPSPs in WT mice and had no significant effect in CD14 KO mice. Furthermore, (+)-naloxone, a TLR4-MD-2 complex inhibitor, blocked LPS effects on eIPSPs in WT mice and delayed the ethanol-induced potentiation of GABAergic transmission. In CeA neurons of CD14 KO mice, (+)-naloxone alone diminished eIPSPs, and subsequent co-application of 100 mM ethanol restored the eIPSPs to baseline levels. In summary, our results indicate that TLR4 and CD14 signaling play an important role in the acute ethanol effects on GABAergic transmission in the CeA and support the idea that CD14 and TLR4 may be therapeutic targets for treatment of alcohol abuse.  相似文献   
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Brain functional connectivity (FC) derived from resting-state functional magnetic resonance imaging (rs-fMRI) has been widely employed to study neuropsychiatric disorders such as autism spectrum disorder (ASD). Existing studies usually suffer from (1) significant data heterogeneity caused by different scanners or studied populations in multiple sites, (2) curse of dimensionality caused by millions of voxels in each fMRI scan and a very limited number (tens or hundreds) of training samples, and (3) poor interpretability, which hinders the identification of reproducible disease biomarkers. To this end, we propose a Multi-site Clustering and Nested Feature Extraction (MC-NFE) method for fMRI-based ASD detection. Specifically, we first divide multi-site training data into ASD and healthy control (HC) groups. To model inter-site heterogeneity within each category, we use a similarity-driven multiview linear reconstruction model to learn latent representations and perform subject clustering within each group. We then design a nested singular value decomposition (SVD) method to mitigate inter-site heterogeneity and extract FC features by learning both local cluster-shared features across sites within each category and global category-shared features across ASD and HC groups, followed by a linear support vector machine (SVM) for ASD detection. Experimental results on 609 subjects with rs-fMRI from the ABIDE database with 21 imaging sites suggest that the proposed MC-NFE outperforms several state-of-the-art methods in ASD detection. The most discriminative FCs identified by the MC-NFE are mainly located in default mode network, salience network, and cerebellum region, which could be used as potential biomarkers for fMRI-based ASD analysis.  相似文献   
35.
Folliculogenesis describes the process of activating an oocyte-containing primordial follicle from the ovarian reserve and its development to the mature ovulatory stage. This process is highly complex and is controlled by extra- and intra-ovarian signaling events. Oocyte competence and capacity for fertilization to support a viable pregnancy are acquired during folliculogenesis. Cancer and cancer-based therapies can negatively affect this process, compromising fertility. Currently, preservation of fertility in these patients remains limited to surrogacy, oocyte freezing, oocyte donation, or in vitro maturation (IVM). Recent reports of stem cells being used to produce fully competent oocytes and subsequently healthy offspring in mice have opened up a novel avenue for fertility preservation. However, translating these findings into human health first relies on enhancing our understanding of follicle growth and mimicking its intricacies in vitro. Indeed, the future of oocytes from stem cells in humans comes with many possibilities but currently faces several technical and ethical obstacles.  相似文献   
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目的:探讨Acsl4在浸润性乳腺癌组织中的表达及其临床意义。方法:采用免疫组织化学法检测108例浸润性乳腺癌组织中Acsl4的表达。结果:108例浸润性乳腺癌组织中,33例(30.6%)阳性表达,75例(69.4%)阴性表达。组织学G3级的乳腺癌组织中Acsl4阳性率为42.3%(22/52),高于G1+G2级的阳性率(19.6%,11/56),差异具有统计学意义(P<0.05)。ER阳性组织的Acsl4的阳性率15.8%(6/38),低于ER阴性的病例(38.6%,27/70),差异具有统计学意义(P<0.05)。Acsl4的表达与患者年龄、肿瘤大小、淋巴结是否转移、HER2、PR、p53、Ki67的表达情况无统计学意义的相关性(P均>0.05)。结论:Acsl4在浸润性乳腺癌组织中存在异常表达,其阳性表达与乳腺癌患者组织学分级较高及ER阴性表达密切相关。  相似文献   
38.
The Mayaro virus (MAYV) belongs to genus “Alphavirus” and family “Togaviridae”. MAYV has distribution in the Amazonia, Central and Northeastern regions of Brazil. The abundance of mosquito vector Haemagogus janthinomys has major role in the outbreaks of arthralgia disease in Brazil. Vaccination or immunization is an alternative approach for the protection against this disease. To search the effective candidate for vaccine against Mayaro virus, various immunoinformatics tools were used to predict both the B and T cell epitopes from five structural polyproteins (capsid, E2, 6K, E3and E1). A multi subunit vaccine was designed and the final sequence was modeled for docking with TLR-3. Human b defensin based on previous studies was used as linker. The docked complexes of vaccine-TLR-3 were then subjected to dynamics stability and RMSD and RMSF results suggested that the complexes are stable. Further, to validate our final vaccine construct, in silico cloning was carried out using E. coli as host. The CAI value of 0.96 suggests that the vaccine construct properly expresses in the host. The current findings will be useful for the future experimental validations to ratify the immunogenicity and safety of the supposed structure of vaccine, and ultimately to treat the Mayaro virus, associated infections.  相似文献   
39.
A novel method for the segmentation of serial images is proposed. In the presented framework, the driving force acts as the attracting term to propel the evolving curve towards the object boundaries, and the adaptive term changes the sign of driving force accordingly. Therefore, the evolving curves can arrive at the desired direction without a requirement for the initial curve to be strictly inside or outside the object. A weighted length term is used to keep the smoothness of curve and penalize the formulation of discontinuities. To prevent the level set function deviating from a signed distance function, a distance rectifying flow is also added to the model; therefore the time-consuming re-initialization procedure is completely avoided. Experiments on both synthetic image and CT serial images demonstrate the feasibility and efficiency of the method.  相似文献   
40.
背景 多潘立酮为胃肠促动力药,自2012年起连续载入《国家基本药物》。鉴于2012-2014年加拿大、美国、英国等指出多潘立酮有导致心源性猝死及突发室性心律失常的风险,特别是年龄超过60岁、每天用药超过30 mg的患者。2016年9月,我国原国家食品药品监督管理总局(CFDA)发布了《关于修订多潘立酮制剂说明书的公告》,提出对多潘立酮说明书内容进行重新修订的要求。此后,多潘立酮生产厂家对多潘立酮说明书“不良反应、禁忌、注意事项、用法用量”等项进行修订,更新后的药品说明书载入了相关警示及风险提示内容。目的 了解多潘立酮片门诊治疗各种疾病的情况,为临床安全、合理用药提供参考。方法 选取2019年3-8月上海市闵行区吴泾社区卫生服务中心门诊医师开具的单一诊断,使用多潘立酮片的处方515张,统计患者的性别、年龄、临床诊断、用法用量等。构建契合社区医疗卫生机构用药特点的知识库智能管理系统。结果 515例使用多潘立酮片患者中,男197例(38.3%),女318例(61.7%);年龄26~98岁,平均年龄(72.0±12.4)岁,以60 岁及以上的老年患者为主〔86.0%(443/515)〕。单一诊断涉及的疾病有19种,其中消化不良、消化性溃疡、慢性胃炎、胃食管反流病居前4位,占81.4%(419/515)。所有患者的每日剂量符合药品说明书规定。结论 门诊多潘立酮片使用基本合理。借助知识库利用信息技术能为患者用药“保驾护航”。  相似文献   
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