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31.
目的探讨五加皮抗肿瘤成分A ge蛋白在正常小鼠与荷瘤小鼠体内的组织分布。方法用氯胺T法对A ge蛋白进行125I标记(形成125I-A ge),由尾iv小鼠后,于不同时间取组织和血液标本,测定放射cpm比值。以放射参与量(即脏器与血液中cpm比值)作为125I-A ge在组织中分布的依据。结果在一次性快速iv125I-A ge 2 h后,正常小鼠和荷瘤小鼠体内均以肾脏中125I-A ge的分布量最高,肝脏和肺部放射参与量也较高,与心脏、脾脏等其他脏器相比差异有显著性(P<0.01);尿中125I-A ge的量很高。iv同等剂量125I-A ge后,荷瘤小鼠的肾脏、肝脏和肺部组织的放射参与量比正常小鼠偏高(P<0.05)。结论五加皮A ge蛋白在小鼠体内主要分布于血流丰富的组织,主要通过泌尿系统排泄,不易透过血脑屏障。 相似文献
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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
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OBJECTIVE:To investigate the effects of active con- stituents extracted from Cortex Acanthopanacis Radicison improving the impaired memory in mice models. METHODS: The mice models of memory impair- ment were established using scopolamine. Amelio- rating effects of the fractions and constituents on scopolamine-induced memory impairment in vivo were investigated using passive avoidance and Morris water-maze task tests, and their anti-acetyl- cholinesterase(AChE) and antioxidant activities in vitro examined. The isolation of constituents was performed by chromatographic methods and their structures were identified on the basis of instru- mental analysis. RESULTS: Among the fractions tested, ethylacetate fraction exhibited the anti-AChE activity(25.83%± 0.23%) properly and excellent 2,2-diphenyl-1-picryl- hydrazyl(DPPH) radical and superoxide anion scav- enging capacity(87.50% ± 0.83% and 60.22% ± 0.43%, respectively). However, the methylene chlo- ride fraction was much more active than the ethyl- acetate fraction in the passive avoidance task test(167.5% increase of step-through latency time) and Morris water-maze task test(33.3% decrease of es-cape latency time). Four constituents, β-sitosterol, stigmasterol, sesamin, and hyperin were isolated from the methylene chloride fraction, among them, hyperin showed anti-acetylcholinesterase and anti-oxidant activities remarkably. Moreover, hyperin exerted a potent effect(146±38) s on mem- ory improvement in terms of passive avoidance task test compared with the reference compound tacrine(162±43) s at a dose of 2.5 mg/kg. CONCLUSION: Hyperin, a flavonoid glucoside iso- lated from Cortex Acanthopanacis Radicis, inhibited AChE activity and potently ameliorated scopol- amine-induced memory impairment, and its action may be partially mediated by the acetylcholine-en- hancing cholinergic nervous system. 相似文献
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《Medical image analysis》2014,18(8):1349-1360
Current neuroimaging investigation of the white matter typically focuses on measurements derived from diffusion tensor imaging, such as fractional anisotropy (FA). In contrast, imaging studies of the gray matter oftentimes focus on morphological features such as cortical thickness, folding and surface curvature. As a result, it is not clear how to combine findings from these two types of approaches in order to obtain a consistent picture of morphological changes in both gray and white matter.In this paper, we propose a joint investigation of gray and white matter morphology by combining geometrical information from white and the gray matter. To achieve this, we first introduce a novel method for computing multi-scale white matter tract geometry. Its formulation is based on the differential geometry of curve sets and is easily incorporated into a continuous scale-space framework.We then incorporate this method into a novel framework for “fusing” white and gray matter geometrical information. Given a set of fiber tracts originating in a particular cortical region, the key idea is to compute two scalar fields that represent geometrical characteristics of the white matter and of the surface of the cortical region. A quantitative marker is created by combining the distributions of these scalar values using Mutual Information. This marker can be then used in the study of normal and pathological brain structure and development. We apply this framework to a study on autism spectrum disorder in children. Our preliminary results support the view that autism may be characterized by early brain overgrowth, followed by reduced or arrested growth (Courchesne, 2004). 相似文献
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Nitric oxide (NO) is an important biomolecule for regulating various brain functions, such as the control of neurovascular tone. NO, however, cannot be stored inside cells where NO is produced and immediately diffuses through the cellular membrane and decays rapidly, which makes the detection of NO extremely hard in an in vivo setting. We constructed an amperometric NO nanosensor and utilized it to directly measure NO release in the living brain. The NO nanosensor uses nanopores (pores with an opening radii <500 nm) in which NO is oxidized at the porous platinum surface. The nanopore-based sensor was inserted vertically into the brains of anesthetized mice up to the end of the hippocampal CA 3 region, or to a depth of about 3 mm. The sensor was slowly advanced in the brain in 0.5 μm increments and in 0.05 s temporal steps. Different levels of NO release were monitored by the nanopore NO sensor during the course of the penetration. The hippocampal CA3 region had the highest level of NO release, which was followed by CA2 and CA1 of the hippocampus and the cortex. The levels of NO release were not uniformly distributed within the cortical and hippocampal areas of living brain. In sum, the nanopore-based NO sensor was able to grossly measure NO contents within living brain in real time and with high sensitivity. This study may provide good insights about the relationship between the distributions of NOS-immunoreactive neurons and the directly measured levels of NO release in brain. 相似文献
40.
目的 分析黄柏、关黄柏粗皮及药材中盐酸小檗碱的分布情况.方法 采用HPLC法分别测定黄柏、关黄柏粗皮部分,去粗皮部分和原药材的盐酸小檗碱的含量,比较液相色谱图中色谱峰的差异.结果 盐酸小檗碱在粗皮中含量低,粗皮部位的色谱图与药材的色谱图不全相同.结论 粗皮成分应进一步分析,黄柏和关黄柏应严格按照药典的加工要求去除粗皮部位. 相似文献