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[摘要] 目的 探讨新型冠状病毒肺炎(coronavirus disease 2019, COVID-19)无症状感染者的临床和免疫学特征。方法 选取2020年1月22日—6月22日石家庄市第五医院收治的59例COVID-19患者作为研究对象,分析不同疾病分期患者的临床资料。利用流式细胞术检测患者外周血T淋巴细胞亚群计数,Procarta Plex多细胞因子检测系统检测外周血25种细胞因子和9种趋化因子水平。结果 59例COVID-19患者中,无症状感染组28例(47.5%)、轻型组6例(10.2%)、普通型组19例(32.2%),重型/危重型组6例(10.2%)。无症状感染组中位年龄为23.0(19.3,34.8)岁,显著低于普通型组的35.0(24.0,52.0)岁和重型/危重型组的64.5(52.0,68.3)岁(P均<0.05)。无症状感染组患者较少患有基础疾病,均无症状、体征和胸部CT变化,其外周血CD3+ T细胞、CD4+ T细胞、CD8+ T细胞计数均显著高于重型/危重型组(P均<0.05),同时CD4+ T细胞计数显著高于普通型组(P<0.05)。14例无症状感染组患者治疗前与治疗后CD3+ T细胞、CD4+ T细胞和CD8+ T细胞计数比较,差异均无统计学意义(P均>0.05)。14例无症状感染组患者治疗前后CD4+ T细胞计数的变化幅度均显著低于普通型组、重型/危重型组(P均<0.05)。无症状感染组外周血可检测到11种细胞因子和趋化因子,其中IL-7水平显著高于对照组, IP-10水平均显著低于普通型组、重型/危重型组,差异均具有统计学意义(P均<0.05)。结论 COVID-19无症状感染者以青年为主,但未发现与性别因素相关。随着COVID-19病情进展,普通型、重型/危重型患者外周血T细胞亚群计数降低,而细胞因子和趋化因子水平升高,但上述指标在无症状感染者中未见显著改变。  相似文献   
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目的 探讨CC亚族趋化因子配体20(CCL20)在食管癌中的表达及对病程进展和预后的影响。 方法 利用癌基因组图谱 (TCGA)、UALCAN、GEO等相关数据库分析CCL20基因在食管癌组织与癌旁组织中的表达差异,通过Kaplan-Meier模型探讨CCL20表达水平与预后的关联性;分析CCL20与肥胖、甲基化等之间的关系;最后通过mRNA、蛋白水平,分析CCL20在食管癌组织和癌旁组织的表达差异。 结果 CCL20在食管癌尤其是腺癌类型中高表达,高表达CCL20患者生存率明显降低;CCL20的表达量与食管癌患者肥胖程度成正比、与其甲基化程度成反比;食管癌组织中CCL20的表达量显著增加。 结论 CCL20在食管癌组织中高表达,且CCL20高表达与患者的生存预后成显著负相关。  相似文献   
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目的探讨血清生长分化因子15(GDF-15)和趋化因子配体12(CXCL12)检测在老年慢性阻塞性肺疾病急性加重期(AECOPD)的应用价值。方法选取2017年1月至2018年12月该院诊治的119例慢性阻塞性肺疾病(COPD)患者,根据病情轻重分为AECOPD组(68例)和COPD稳定期组(51例),选取同期60例健康体检者作为对照组,检测各组血清GDF-15、CXCL12和降钙素原(PCT)水平,收集3组肺功能结果和慢性阻塞性肺疾病评估测试量表(CAT)评分。结果AECOPD组和COPD稳定期组血清GDF-15、CXCL12、PCT水平和CAT评分高于对照组(P<0.05),AECOPD组血清GDF-15、CXCL12、PCT水平和CAT评分高于COPD稳定期组(P<0.05)。AECOPD组和COPD稳定期组第1秒用力呼气容积占预计值的百分比(FEV1%pred)和第1秒用力呼气容积与用力肺活量比值(FEV1/FVC)水平低于对照组,AECOPD组FEV1%pred和FEV1/FVC水平低于COPD稳定期组(P<0.05)。血清GDF-15、CXCL12、PCT水平与FEV1%pred和FEV1/FVC呈负相关(P<0.05),与CAT评分呈正相关(P<0.05)。受试者工作特征(ROC)曲线分析显示,血清GDF-15、CXCL12对AECOPD的诊断价值优于PCT。结论老年AECOPD患者血清GDF-15、CXCL12水平上升,与肺功能和CAT评分密切相关,GDF-15和CXCL12可作为老年AECOPD的诊断指标。  相似文献   
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BackgroundCytokines and chemokines play critical roles in the pathogenesis of asthma. Azithromycin, a macrolides, is frequently used in asthmatic children with lower respiratory tract infection and is reported having anti-inflammatory and immunomodulatory effects. However, the effects of azithromycin on the expression of TNF-α, Th1- and Th2-related chemokines, and neutrophil chemoattractant are unknown. We investigated the in vitro effects of azithromycin on the expression of TNF-α, Th1-related chemokine interferon-γ-inducible protein-10 (IP-10/CXCL10), Th2-related chemokine macrophage-derived chemokine (MDC/CCL22) and neutrophil chemoattractant growth-related oncogene-α (GRO-α/CXCL1) in THP-1 cells as a model for human monocytes.MethodsTHP-1 cells were pretreated with various concentrations of azithromycin before Toll-like receptor 4 (TLR4) agonist lipopolysaccharide (LPS) stimulation. TNF-α, IP-10, MDC and GRO-α were measured by ELISA. Intracellular signaling was investigated by pathway inhibitors and Western blot.ResultAzithromycin suppressed MDC and IP-10 expression in LPS-stimulated THP-1 cells. However, azithromycin had no effect LPS-induced TNF-α and GRO-α expression. Western blotting revealed that azithromycin suppressed LPS-induced phosphorylation of mitogen-activated protein kinase (MAPK)–JNK and ERK expression, and also suppressed LPS-induced phosphorylation of nuclear factor (NF) κB–p65 expression.ConclusionAzithromycin suppressed LPS-induced MDC expression via the MAPK–JNK and the NFκB–p65 pathway. Azithromycin also suppressed LPS-induced IP-10 via the MAPK–JNK/ERK and the NFκB–p65 pathway. Azithromycin may benefit asthmatic patients by suppressing chemokines expression.  相似文献   
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Glutaric Aciduria type I (GA-I) is caused by mutations in the GCDH gene. Its deficiency results in accumulation of the key metabolites glutaric acid (GA) and 3-hydroxyglutaric acid (3-OHGA) in body tissues and fluids. Present knowledge on the neuropathogenesis of GA-I suggests that GA and 3-OHGA have toxic properties on the developing brain.We analyzed morphological and biochemical features of 3D brain cell aggregates issued from Gcdh?/? mice at two different developmental stages, day-in-vitro (DIV) 8 and 14, corresponding to the neonatal period and early childhood. We also induced a metabolic stress by exposing the aggregates to 10 mM l-lysine (Lys).Significant amounts of GA and 3-OHGA were detected in Gcdh?/? aggregates and their culture media. Ammonium was significantly increased in culture media of Gcdh?/? aggregates at the early developmental stage. Concentrations of GA, 3-OHGA and ammonium increased significantly after exposure to Lys. Gcdh?/? aggregates manifested morphological alterations of all brain cell types at DIV 8 while at DIV 14 they were only visible after exposure to Lys. Several chemokine levels were significantly decreased in culture media of Gcdh?/? aggregates at DIV 14 and after exposure to Lys at DIV 8.This new in vitro model for brain damage in GA-I mimics well in vivo conditions. As seen previously in WT aggregates exposed to 3-OHGA, we confirmed a significant ammonium production by immature Gcdh?/? brain cells. We described for the first time a decrease of chemokines in Gcdh?/? culture media which might contribute to brain cell injury in GA-I.  相似文献   
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Tick-borne encephalitis, caused by the tick-borne virus (TBEV), is endemic in central, eastern, and northern Europe eastwards through Russian Siberia and China. For the year 2009, the highest incidence in Scandinavian countries was in Sweden. The clinical symptoms have a wide spectrum. We report a unique case of clinical symptoms and radiological findings compatible with a stroke-like inflammatory lesion in the thalamus, suggesting microangiopathy from TBEV. Our case shows that TBEV could be a possible cause of stroke-like lesions.  相似文献   
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Eosinophils are multifaceted immune cells with diverse functions that enhance allergic inflammation. Cysteinyl leukotrienes (cys-LTs), mainly synthesized in eosinophils, are a class of inflammatory lipid mediators produced via multiple enzymatic reactions from arachidonic acid. Multiple clinical studies have reported dysregulated fatty acid metabolism in severe asthma and aspirin-exacerbated respiratory diseases. Therefore, understanding the mechanism responsible for this metabolic abnormality has attracted a lot of attention. In eosinophils, various stimuli (including cytokines, chemokines, and pathogen-derived factors) prime and/or induce leukotriene generation and secretion. Cell–cell interactions with component cells (endothelial cells, epithelial cells, fibroblasts) also enhance this machinery to augment allergic responses. Nasal polyp-derived eosinophils from patients with eosinophilic rhinosinusitis present a characteristic fatty acid metabolism with selectively higher production of leukotriene D4. Interestingly, type 2 cytokines and microbiome components might be responsible for this metabolic change with altered enzyme expression. Here, we review the regulation of fatty acid metabolism, especially cys-LT metabolism, in human eosinophils toward allergic inflammatory status.  相似文献   
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