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目的:研究在膀胱癌化疗中使用姜黄素的增敏功能原理。方法:在T24细胞经过姜黄素及放射处理后,探讨分析其细胞活力(细胞增殖试验试剂盒)、microRNA表达(miRNA芯片测序)、集落形成、凋亡(AnnexinV-F)分析、miR-1246及p53 mRNA及蛋白质(Westernblot)表达、ITC/7-AAD流式细胞计数(ITC/7-AAD)。结果:通过测试,发现17个异常microRNA表达,细胞在经过姜黄素处理后,T24细胞活力相较于常规组明显下降,并出现浓度依赖性的现象。在T24细胞中,miR-1246相较于人膀胱上皮永生化细胞(SV-HUC-1细胞)表达明显较高。姜黄素的浓度较高时,T24细胞miR-1246的表达会受其影响并明显下降。研究组使用浓度为20μg/mL的姜黄素,并结合放疗处理的方式,与常规组相比,研究组在控制miR-1246的表达、集落形成及细胞活力方面,效果更为显著,T24细胞比例会因转染antagomiR-1246而增加,细胞死亡现象一般发生于转染antagomiR-NC细胞时期。结论:膀胱癌细胞中,姜黄素和放射治疗都可促进microRNA-1246表达下调,在对肿瘤的治疗中可以使姜黄素及放疗结合,共同产生抗肿瘤作用。  相似文献   
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BackgroundNonalcoholic fatty liver diseases (NAFLD) is a highly prevalent disease that is closely associated with several cardiometabolic complications. The potential anti-inflammatory role of curcuminoids that have already been reported to reduce hepatic steatosis, in patients with NAFLD was explored in this study.MethodsThis double-blind, randomized placebo-controlled trial was conducted for a period of 8 weeks in patients with NAFLD. Subjects (n = 55) were randomly allocated to receive either curcuminoids or placebo. The curcuminoids group received one capsule containing 500 mg curcuminoids (plus 5 mg piperine to increase intestinal absorption) per day for 8 weeks and the control group received matched placebo capsules for the same period. Liver ultrasonography was performed to assess the severity of hepatic steatosis at baseline and the study end. Serum levels of cytokines including interleukin-1α, interleukin-1β, interleukin-2, interleukin-4, interleukin-6, interleukin-8, interleukin-10, tumor necrosis factor-α, monocyte chemoattractant protein-1, interferon γ, vascular endothelial growth factor and epidermal growth factor were measured before and after the intervention.ResultsThe two groups were comparable in demographic features at baseline. The results showed that supplementation with curcuminoids could decrease weight compared to the placebo group (p = 0.016) in patients with NAFLD. Curcuminoids supplementation improved the severity of NAFLD according to the ultrasound results (p = 0.002). Moreover, serum concentrations of TNF-α (p = 0.024), MCP-1 (p = 0.008) and EGF (p = 0.0001) were improved by curcuminoids in NAFLD patients.ConclusionsThe results of our study showed that curcumin supplementation can improve serum levels of inflammatory cytokines in subjects with NAFLD and this might be at least partly responsible for the anti-steatotic effects of curcuminoids.  相似文献   
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ObjectiveMethamphetamine is used extensively around the world as a psychostimulant. The complications related to methamphetamine include methamphetamine-induced neurotoxicity, mainly involving intraneuronal processes, such as oxidative stress and excitotoxicity. Curcumin is effective against neuronal injury due to its antioxidant, anti-inflammatory effects. In this study, we examined the protective effects of curcumin against methamphetamine neurotoxicity.MethodsSixty male Wistar rats were divided into the following groups: control (n = 12), DMSO (n = 12), methamphetamine (n = 12), and methamphetamine + curcumin (100 and 200 mg/kg, respectively, intraperitoneal [IP]; n = 12). Neurotoxicity was induced by 40 mg/kg of methamphetamine administrated through 4 injections (4 × 10 mg/kg, q2h, IP). Curcumin (100 and 200 mg/kg) was administered at 7 days after the last methamphetamine injection. By using a Morris water maze task, the hippocampus-dependent memory and spatial learning were evaluated 1 day after the last curcumin injection. Then, the animal brains were isolated for biochemical measurements, as well as glial fibrillary acidic protein (GFAP), ionized calcium-binding adaptor protein-1(Iba-1) and caspase-3 immunohistochemical staining.ResultsThe current study demonstrated that administration of curcumin significantly attenuates spatial memory impairment (P < 0.01) following methamphetamine neurotoxicity. Curcumin caused a significant increase in the levels of superoxide dismutase and glutathione peroxidase (P < 0.05). However, it decreased tumor necrosis factor (TNF-α) (P < 0.05) and malondialdehyde (P < 0.01) levels as compared to the methamphetamine group. Also, curcumin significantly reduced Iba-1 (P < 0. 01), GFAP and caspase-3 positive cells in the hippocampus (P < 0.001).ConclusionCurcumin exerted neuroprotective effects on methamphetamine neurotoxicity because of its antioxidant and anti-inflammatory effect.  相似文献   
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The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats.  相似文献   
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The transdermal permeation of curcumin aided by choline and geranic acid ionic liquid (CAGE-IL) was addressed as a potential treatment for skin diseases. An in-depth analysis of the effect of CAGE-IL concentration in the enhancement of transdermal permeation of curcumin was performed, and the results were modelled via nonlinear regression analysis. The results obtained showed that a low percentage of CAGE-IL (viz. 2.0%, w/w) was effective in disrupting the skin structure in a transient fashion, facilitating the passage of curcumin dissolved in it.  相似文献   
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ObjectivesAcetaminophen (APAP)-induced nephrotoxicity is detrimental consequence for which there has not been a standardized therapeutic regimen. Although, N-acetylcysteine (NAC) is a well-known antidote used in APAP-induced hepatotoxicity, its benefit in nephrotoxicity caused by APAP is almost lacking. This study aimed to compare the possible protective effect of thymoquinone (TQ), curcumin (CR), and α-lipoic acid (α-LA), either in solo or in combination regimens with that of NAC against APAP-induced renal injury.Design and methodRats were divided into nine groups; control group, APAP intoxicated group (1000 mg/kg; orally), and the remaining seven groups received, in addition to APAP, oral doses of NAC, TQ, CR, α-LA, CR plus TQ, TQ plus α-LA, or CR plus α-LA. The first dose of the aforementioned antioxidants was given 24 h before APAP, and then the second dose was given 2 h after APAP, whereas the last dose was given 10 h after administration of APAP.ResultsTreatment with APAP elevated kidney markers like serum uric acid, urea, and creatinine. In addition, it increased the serum level of tumor necrosis factor alpha (TNF-α), interleukin-1beta (IL-1β) and thiobarbituric acid reactive species (TBARS). Also, the protein expression of renal janus kinase (JAK) and cyclooxygenase (COX)-2 were all upregulated by APAP. In contrast, the expression of Nrf2 and the renal levels of superoxide dismutase and glutathione were downregulated. Treatment with the indicated natural antioxidants resulted in amelioration of the aberrated parameters through exhibiting anti-inflammatory, antioxidant and free radical-scavenging effects with a variable degree.ConclusionThe combined administration of CR and TQ exerted the most potent protection against APAP-induced nephrotoxicity through its anti-inflammatory and free radical-scavenging effects (antioxidant) which were comparable to that of NAC-treatment.  相似文献   
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目的探讨姜黄素调控miR-199a-3p的基因表达对前列腺癌C4-2细胞增殖、迁移和侵袭的影响。方法将miR-199a-3p抑制物及阴性对照转染至C4-2细胞中,并分别标记为anti-miR-199a-3p组和anti-miR-con组;将仅加入脂质体的C4-2细胞标记为对照组。运用MTT法检测通过姜黄素(0、20、40、80μmol/L)处理的C4-2细胞的增殖情况。40μmol/L姜黄素处理C4-2细胞后,Transwell法检测细胞的迁移和侵袭能力;qRT-PCR检测细胞的miR-199a-3p表达量。将inhibitor NC、miR-199a-3p inhibitor转染至C4-2细胞中,再用40μmol/L姜黄素处理48 h,采用MTT法、Transwell法检测各组细胞的增殖、迁移和侵袭情况;Western blot检测各组C4-2细胞中基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)、β-catenin、Cyclin D1和c-Myc的蛋白表达量。结果与对照组比较,姜黄素能明显抑制C4-2细胞的增殖、迁移和侵袭(P<0.05)。姜黄素(40μmol/L)处理后,C4-2细胞中miR-199a-3p的表达量显著增加(P<0.05)。抑制miR-199a-3p的表达,可逆转姜黄素对C4-2细胞增殖、迁移和侵袭的抑制作用(P<0.05)。使用姜黄素处理miR-199a-3p低表达的C4-2细胞后,与anti-miR-con组相比,anti-miR-199a-3p组C4-2细胞的MMP-2、MMP-9的表达量显著增加(P<0.05),β-catenin、Cyclin D1和c-Myc蛋白表达量均显著增加(P<0.05)。结论姜黄素可上调miR-199a-3p的表达,从而抑制前列腺癌C4-2细胞的增殖、迁移和侵袭。  相似文献   
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