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91.
Although axonal damage induces significant retinal ganglion cell (RGC) death, small numbers of RGCs are able to survive up to 7 days after optic nerve crush (NC) injury. To develop new treatments, we set out to identify patterns of change in the gene expression of axonal damage‐resistant RGCs. To compensate for the low density of RGCs in the retina, we performed retrograde labeling of these cells with 4Di‐10ASP in adult mice and 7 days after NC purified the RGCs with fluorescence‐activated cell sorting. Gene expression in the cells was determined with a microarray, and the expression of Ho‐1 was determined with quantitative PCR (qPCR). Changes in protein expression were assessed with immunohistochemistry and immunoblotting. Additionally, the density of Fluoro‐gold‐labeled RGCs was counted in retinas from mice pretreated with CoPP, a potent HO‐1 inducer. The microarray and qPCR analyses showed increased expression of Ho‐1 in the post‐NC RGCs. Immunohistochemistry also showed that HO‐1‐positive cells were present in the ganglion cell layer (GCL), and cell counting showed that the proportion of HO‐1‐positive cells in the GCL rose significantly after NC. Seven days after NC, the number of RGCs in the CoPP‐treated mice was significantly higher than in the control mice. Combined pretreatment with SnPP, an HO‐1 inhibitor, suppressed the neuroprotective effect of CoPP. These results reflect changes in HO‐1 activity to RGCs that are a key part of RGC survival. Upregulation of HO‐1 signaling may therefore be a novel therapeutic strategy for glaucoma. © 2014 Wiley Periodicals, Inc.  相似文献   
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Risperidone, an atypical antipsychotic drug, has been discovered to have some beneficial effects beyond its original effectiveness. The present study examines the neuroprotective effects of risperidone against ischemic damage in the rat and gerbil induced by transient focal and global cerebral ischemia, respectively. The results showed that pre‐ and posttreatment with 4 mg/kg risperidone significantly protected against neuronal death from ischemic injury. Many NeuN‐immunoreactive neurons and a few F‐J B‐positive cells were found in the rat cerebral cortex and gerbil hippocampal CA1 region (CA1) in the risperidone‐treated ischemia groups compared with those in the vehicle‐treated ischemia group. In addition, treatment with risperidone markedly attenuated the activation of microglia in the gerbil CA1. On the other hand, we found that treatment with risperidone significantly maintained the antioxidants levels in the ischemic gerbil CA1. Immunoreactivities of superoxide dismutases 1 and 2, catalase, and glutathione peroxidase were maintained in the stratum pyramidale of the CA1; the antioxidants were very different from those in the vehicle‐treated ischemia groups. In brief, our present findings indicate that posttreatment as well as pretreatment with risperidone can protect neurons in the rat cerebral cortex and gerbils CA1 from transient cerebral ischemic injury and that the neuroprotective effect of risperidone may be related to attenuation of microglial activation as well as maintenance of antioxidants. © 2014 Wiley Periodicals, Inc.  相似文献   
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目的明确左旋多巴对PC12细胞生长及应激状态下存活的影响,探讨其抗氧化应激损伤的机制。方法不同浓度左旋多巴处理PC12细胞,用MTT法检测PC12细胞增长率及加入过氧化氢后细胞存活率;免疫荧光、Western blot方法测定磷酸化环单磷酸腺苷反应元件结合蛋白(pCREB)及CD39蛋白表达。结果低浓度左旋多巴(20μmol·L-1)促进PC12细胞生长,且可抗氧化应激损伤,而蛋白激酶抑制剂减弱此保护作用。免疫荧光及Western blot结果显示CD39及pCREB表达升高。结论低浓度左旋多巴可通过上调CD39及pCREB表达发挥抗氧化应激神经保护作用。  相似文献   
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Several studies have demonstrated that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats with diabetes mellitus. It is hypothesized that L-carnitine exhibits neuro-protective effects on injured sciatic nerve of rats. Rat sciatic nerve was crush injured by a forceps and exhibited degenerative changes. After intragastric administration of 50 and 100 mg/kg L-carnitine for 30 days, axon area, myelin sheath area, axon diameter, myelin sheath diameter, and numerical density of the myelinated axons of injured sciatic nerve were similar to normal, and the function of injured sciatic nerve also improved signiifcantly. These ifndings suggest that L-carnitine exhibits neuroprotective effects on sciatic nerve crush injury in rats.  相似文献   
98.
The purpose of this work was to investigate whether, by intranasal administration, the nerve growth factor bypasses the blood-brain barrier and turns over the spinal cord neurons and if such therapeutic approach could be of value in the treatment of spinal cord injury. Adult Sprague-Dawley rats with intact and injured spinal cord received daily intranasal nerve growth factor administration in both nostrils for 1 day or for 3 consecutive weeks. We found an in-creased content of nerve growth factor and enhanced expression of nerve growth factor receptor in the spinal cord 24 hours after a single intranasal administration of nerve growth factor in healthy rats, while daily treatment for 3 weeks in a model of spinal cord injury improved the deifcits in locomotor behaviour and increased spinal content of both nerve growth factor and nerve growth factor receptors. These outcomes suggest that the intranasal nerve growth factor bypasses blood-brain barrier and affects spinal cord neurons in spinal cord injury. They also suggest exploiting the possible therapeutic role of intranasally delivered nerve growth factor for the neuroprotection of damaged spinal nerve cells.  相似文献   
99.
Oxidative stress is closely associated with secondary cell death in many disorders of the central nervous system including stroke,Parkinson’s disease,Alzheimer’s disease.Among many aberrant oxidative stress-associated proteins,DJ-1 has been associated with the oxidative stress cell death cascade primarily in Parkinson’s disease.Although principally expressed in the cytoplasm and nucleus,DJ-1 can be secreted into the serum under pathological condition.Recently,a close pathological association between DJ-1 and oxidative stress in stroke has been implicated.To this end,we and others have demonstrated the important role of mitochondria in neuroprotection for stroke by demonstrating that the translocation of DJ-1 in the mitochondria could potentially mitigate mitochondrial injury.Here,we discuss our recent findings testing the hypothesis that DJ-1 not only functions as a form of intracellular protection from oxidative stress,but that it also utilizes paracrine and/or autocrine cues in order to accomplish extracellular signaling between neighboring neuronal cells,resulting in neuroprotection.This article highlights recent evidence supporting the status of DJ-1 as key anti-oxidative stress therapeutic target for stroke.  相似文献   
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