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1.
PurposeEpidermal hyperplasia and the involvement of immune cells characterize the clinical picture of psoriasis. Among the several factors involved, attention has been focused on sirtuin 1 (SIRT1) - a deacetylase endowed with a variety of functions including the control of metabolic and inflammatory processes-, and on nicotinamide phosphoribosyltransferase (NAMPT), important for SIRT1 activation and involved in inflammatory events. The aim of the study was to analyze changes of SIRT1 and NAMPT expression in psoriatic skin.Patients and methodsSamples from healthy controls and psoriatic patients were subjected to immunohistochemical analysis.ResultsA strong downregulation of SIRT1 expression was observed in skin samples from psoriatic patients compared to healthy controls. This was accompanied by a parallel reduction of adenosine monophosphate-activated kinase (AMPK) expression and, more strikingly, by the disappearance of cells immunolabeled for its active, phosphorylated form (pAMPK). In both cases, analysis of the distribution of immunopositive cells revealed a shift towards reduced intensity of staining. In contrast, NAMPT expression was upregulated in psoriatic samples in line with its pro-inflammatory role. This was again more visible with an intensity-based distribution analysis that evidenced a shift towards more intensely immunostained cell populations.ConclusionsThe present data correlate in the same samples the expression of SIRT1, pAMPK/AMPK and NAMPT in psoriasis and open the way for novel pharmacological targets in the treatment of the disease.  相似文献   
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目的研究肿瘤蛋白翻译调节因子1反义-RNA1(TPT1-AS1)在肝细胞和肝癌细胞中表达的差异,及其对肝细胞癌增殖、迁移、侵袭、上皮细胞间质化(EMT)的影响。方法2018年9月—2020年6月于西安交通大学实验室进行细胞实验,使用qRT-PCR分别检测92例经手术切除的肝癌组织与对应癌旁肝组织,肝癌细胞HepG2、SNU-182和人肝永生化细胞THLE-3中TPT1-AS1相对表达量。根据qRT-PCR测得肝癌组织中TPT1-AS1表达量中位数(3.38),将患者分为TPT1-AS1高表达组(n=46)和低表达组(n=46)。使用Kaplan-Meier法分析比较2组患者5年生存率的差异。使用siRNA转染HepG2和SNU-182细胞以沉默TPT1-AS1表达,以阴性对照siRNA(si-NC)转染相同细胞作为对照。比较siRNA和si-NC转染HepG2和SNU-182细胞后的增殖、迁移、侵袭、EMT能力差异。结果与对应癌旁组织比较,肝癌组织中TPT1-AS1相对表达水平升高(t/P=54.065/0.000)。高表达组患者BCLC分期C期比例、淋巴结转移比例更高(χ2/P=15.187/0.001,7.379/0.007)。高表达组患者5年生存率低于低表达组(χ2/P=7.354/0.007)。使用siRNA转染的HepG2和SNU-182细胞较si-NC转染对应细胞的细胞集落数量明显减少,G0/G1期细胞比例升高(P均=0.000),S期细胞比例显著降低(P均=0.000),相对迁移距离降低(t/P=25.153/0.000),穿透基底膜的细胞数量减少,G1/S期转换及EMT相关蛋白CDK4、N-cadherin和Vimentin的相对表达量降低(P均=0.000),而p21和E-cadherin蛋白相对表达量升高(P均=0.000)。结论长链非编码RNA TPT1-AS1促进肝癌细胞增殖、迁移、侵袭和EMT,TPT1-AS1有可能作为肝细胞癌的治疗靶点。  相似文献   
3.
肝内胆管癌(ICC)侵袭性强、预后差,目前缺乏有效的辅助治疗措施。随着对ICC相关肿瘤微环境、基因、蛋白、表观遗传修饰、信号通路等深入研究,潜在治疗靶点不断被发现。本文就近期发现的ICC潜在治疗靶点作一综述。  相似文献   
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目的:基于生物医学大数据筛选幽门螺杆菌(Hp)相关性慢性萎缩性胃炎的关键基因,探索其发病机制及安胃汤对其的影响。方法:从数据库Gene Expression Omnibus(GEO)下载Hp相关性慢性萎缩性胃炎相关芯片数据,利用GEO2R软件筛选出Hp相关性慢性萎缩性胃炎差异基因,进行生物信息学分析,根据蛋白参与通路数量确定核心蛋白,建立Hp阳性慢性萎缩性胃炎大鼠模型,用PCR和蛋白质印迹法(Western Blotting)进行检测并观察安胃汤对其表达的影响。结果:经过检索分析GSE13873和GSE27411系列芯片数据被纳入,取2个芯片交集的20个差异基因进行生物信息学分析,发现载脂蛋白A1、CD36、囊性纤维化穿膜传导调节蛋白(CFTR)可能是信号通路的核心蛋白。Western Blotting及PCR结果显示Hp相关性慢性萎缩性胃炎大鼠胃组织中,CD36蛋白表达下调(P<0.05),载脂蛋白A1和CFTR蛋白表达上调(P<0.05);与模型组比较,实验观察高剂量组、实验观察中剂量组和实验观察低剂量组胃组织中CD36蛋白表达上调,载脂蛋白A1和CFTR表达下调(P<0.05),其与Hp相关性慢性萎缩性胃炎发病关系密切。结论:通过对GEO中Hp相关性慢性萎缩性胃炎芯片生物信息学分析结合Western Blotting及PCR进一步的验证发现载脂蛋白A1、CD36、CFTR作为信号通路的核心蛋白实验结果与生物信息学分析结果一致。  相似文献   
6.
目的:探讨白藜芦醇可否通过SIRT1激活解整合素金属蛋白酶10(ADAM10)促进APPα代谢抑制Aβ分泌。方法:选取过表达人瑞典突变淀粉样前体蛋白APP695sw的细胞模型,分别设立DMSO空白对照组、SIRT1激活剂白藜芦醇组和SIRT1抑制剂EX527组。给药后,ELISA法分别检测细胞培养上清中sAPPα和Aβ的含量,免疫印记Western Blot法检测细胞SIRT1和ADAM10的蛋白水平。结果:与对照组比较,白藜芦醇组细胞培养上清sAPPα的含量增高,Aβ含量下降,sAPPα/Aβ比值增大,细胞SIRT1和ADAM10蛋白水平增高;而抑制剂EX527组与对照相比,细胞培养上清sAPPα的含量降低,Aβ含量升高,sAPPα/Aβ比值减小,细胞SIRT1和ADAM10蛋白水平降低;抑制剂下调SIRT1后各项指标与激动剂组呈现相反的趋势(P<0.05)。结论:白藜芦醇可通过SIRT1激活ADAM10,促进APP进行α非淀粉样代谢途径,增强sAPPα分泌并抑制Aβ产生。  相似文献   
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In recent years, the cross talk between the liver and the immune system is being uncovered, in part by studying liver involvement in primary immune deficiencies (PID) and in part by investigating the alterations of the immune system following orthotopic liver transplantation (OLT). Here we review some of the reciprocal interactions between the liver and the immune system. Patients with PID, particularly those involving inherited defects in T and B cells or innate immunity are prone to infections and inflammatory responses that often involve the liver. Omenn's syndrome, familial hemophagocytic lymphohistiocytosis, AIRE, FOXP3 and CD25 deficiencies, common variable immunodeficiency, CD40 ligand deficiency, chronic granulomatous disease and autoimmune lymphoproliferative syndrome are some of the notable PID associated with typical hepatobiliary abnormalities. Knowledge gained from studying these PID together with laboratory and histological evaluations can assist in managing PID-associated liver dysfunction. The liver itself also has important effects on the immune system, as evident from the growing experience with patients surviving OLT. Up to 40% of pediatric patients who receive OLT suffer from post transplantation allergy, autoimmunity, and immune-mediated disorders (PTAA). PTAA is more common after liver and heart transplantations than kidney transplantations. Potential contributing factors for the increased frequency of PTAA after OLT include the age of the patients, the prolonged use of tacrolimus and the reduced regulatory immune function with a shift towards a TH2 immune response. Better understanding of the mechanisms leading to the development of PTAA after OLT will also improve the management of these conditions.  相似文献   
10.
BackgroundCystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. In this study we assessed the effect of antisense oligonucleotide eluforsen on CFTR biological activity measured by Nasal Potential Difference (NPD) in patients with the most common mutation, F508del-CFTR.MethodsThis multi-centre, exploratory, open-label study recruited adults with CF homozygous or compound heterozygous for the F508del-CFTR mutation. Subjects received intranasal eluforsen three times weekly for 4 weeks. The primary endpoint was the within-subject change from baseline in total chloride transport (Cl-free+iso), as assessed by NPD. Secondary endpoints included within-subject change from baseline in sodium transport.ResultsIn the homozygous cohort (n = 7; per-protocol population), mean change (90% confidence interval) in Cl-free+iso was ?3.0 mV (?6.6; 0.6) at day 15, ?4.1 mV (?7.8; ?0.4, p = .04) at day 26 (end of treatment) and ? 3.7 mV (?8.0; 0.6) at day 47. This was supported by improved sodium transport as assessed by an increase in average basal potential difference at day 26 of +9.4 mV (1.1; 17.7, p = .04). The compound heterozygous cohort (n = 7) did not show improved chloride or sodium transport NPD values. Eluforsen was well tolerated with a favourable safety profile.ConclusionsIn F508del-CFTR homozygous subjects, repeated intranasal administration of eluforsen improved CFTR activity as measured by NPD, an encouraging indicator of biological activity.  相似文献   
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