首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   535篇
  国内免费   45篇
  完全免费   126篇
  综合类   706篇
  2020年   5篇
  2019年   8篇
  2018年   11篇
  2017年   22篇
  2016年   25篇
  2015年   37篇
  2014年   48篇
  2013年   58篇
  2012年   82篇
  2011年   71篇
  2010年   60篇
  2009年   66篇
  2008年   78篇
  2007年   64篇
  2006年   9篇
  2005年   4篇
  2004年   4篇
  2003年   7篇
  2002年   1篇
  2001年   1篇
  1997年   11篇
  1996年   1篇
  1995年   4篇
  1994年   8篇
  1993年   6篇
  1992年   2篇
  1991年   2篇
  1990年   3篇
  1989年   5篇
  1988年   2篇
  1986年   1篇
排序方式: 共有706条查询结果,搜索用时 34 毫秒
1.
Background Sepsis is a leading cause of death in the intensive care units. The late inflammatory cytokine, high-mobility group box 1 (HMGB1), plays a critical role in sepsis. In the present study, we investigated the association between the serum HMGB1 levels and the severity of organ injury in the lipopolysaccharide-induced sepsis in rats.
Methods To produce an animal model of sepsis with different degree of organ injury, animals were treated with three different doses of lipopolysaccharide (4, 8 and 16 mg/kg), and the animals in control group were treated with the same volume of the vehicle (saline). The levels of serum HMGB1 were measured at 0, 2, 4, 8, 16, 24, 32 and 48 hours after lipopolysaccharide (LPS) or vehicle injection, meanwhile the biochemical and histopathological indicators for the severity of organ injury were assessed.
Results The level of HMGB1 had a positive, high correlation with the abnormal changes of serum cardiac troponin I, alanine aminotransferase, aspartate aminotransferase, creatinine and blood urea nitrogen, as well as the pathologic scores of heart, lung, liver and kidney.
Conclusions The level of serum HMGB1 is highly correlated with the severity of sepsis in rats, suggesting that HMGB1 could serve as a valuable adjunct in the diagnosis and management of sepsis.  相似文献
2.
Background The classic glycine receptor (GlyR) in the central nervous system is a ligand-gated membrane-spanning ion channel. Recent studies have provided evidence for the existence of GlyR in endothelial cells, renal proximal tubular cells and most leukocytes. In contrast, no evidence for GlyR in myocardial cells has been found so far. Our recent researches have showed that glycine could protect myocardial cells from the damage induced by lipopolysaccharide (LPS). Further studies suggest that myocardial cells could contain GlyR or binding site of glycine. Methods In isolated rat heart damaged by LPS, the myocardial monophasic action potential (MAP), the heart rate (HR) the myocardial tension and the activities of lactate dehydrogenase (LDH) from the coronary effluent were determined. The concentration of intracellular free calcium ([Ca^2+]i) was measured in cardiomyocytes injured by LPS and by hypoxia/reoxygenation (H/R), which excludes the possibility that reduced calcium influx because of LPS neutralized by glycine. Immunohistochemistry was used to detect the GlyR in myocardial tissue. GlyR and its subunit in the purified cultured cardiomyocytes were identified by Western blotting. Results Although significant improvement in the MAP/MAPD20, HR, and reduction in LDH release were observed in glycine + LPS hearts, myocardial tension did not recover. Further studies demonstrated that glycine could prevent rat mycordial cells from LPS and hypoxia/reoxygenation injury (no endotoxin) by attenuating calcium influx. Immunohistochemistry exhibited a positive green-fluorescence signaling along the cardiac muscle fibers. Western blotting shows that the purified cultured cardiomyocytes express GlyR β subunit, but GlyR α1 subunit could not be detected. Conclusions The results suggest that glycine receptor is expressed in cardiomyocytes and participates in cytoprotection from LPS and hypoxia/reoxygenation injury. Glycine could directly activate GlyR on the cardiomyocytes and prevent calcium influx into the cardiomyocytes.  相似文献
3.
N-乙酰半胱氨酸对脂多糖诱发小鼠早产的防治作用   总被引:5,自引:1,他引:4  
目的 探讨N-乙酰半胱氨酸(NAC)对脂多糖(LPS)诱发小鼠早产的预防和治疗效果及作用机理.方法 将100只孕15 d C57BL/6小鼠随机分为LPS组、NS组、NAC组、治疗作用组和预防作用组,每组20只.在干预后4 h、8 h、12 h、24 h后每个时间点分别处死3只孕鼠,Western Blotting检测子宫组织NF-κB P65,RT-PCR检测IL-8 mRNA水平,试剂盒检测孕鼠血清IL-8、丙二醛(MDA)及超氧化物歧化酶(SOD)浓度,取母、胎肝脏检测谷胱甘肽过氧化物酶(GSH-PX)水平.另每组8只观察NAC对小鼠早产的治疗效果及毒副作用.结果 NAC治疗LPS诱发小鼠早产分娩潜伏期延长至(35.4±2.1) h,活产率为69.0%,NAC预防给药则延长至(44.8±2.6) h,活产率提高至84.3%,与LPS组[(15.1±1.9) h,4.3%]相比差异均有统计学意义(P<0.001).LPS作用4 h、8 h、12 h、24 h后,NF-κB活化增强,在4 h达高峰;子宫组织IL-8 mRNA水平、血清IL-8浓度、MDA均升高,在LPS作用8 h后最高;而活胎率、母胎肝脏GSH-PX以及血清SOD水平均下降,在作用8 h最低.预防作用组和治疗作用组各指标变化程度均减弱,同LPS组比较差异均有统计学意义(P<0.05).结论 NAC对LPS诱发的小鼠早产防治效果明显,且预防作用大于治疗作用.  相似文献
4.
苦参碱对BALB/c免疫性肝损伤小鼠的保护作用   总被引:4,自引:1,他引:3  
目的 研究苦参碱对卡介苗(BCG)和脂多糖(LPS)所致小鼠免疫性肝损伤动物模型的的保护作用.方法 建立BCG+LPS诱导免疫性肝损伤小鼠模型,造模第2天灌胃给苦参碱(Mat)及联苯双酯(Bif),共10d,计算肝脏指数、脾脏指数,分光光度法检测肝组织匀浆中谷胱甘肽过氧化氢酶(GSH-Px)、总抗氧化能力(T-AOC)及丙二醛(MDA).结果 小鼠灌胃给予苦参碱20、40、80 nag/kg,可显著降低肝脏、脾脏指数(P(O.05,P<0.01);降低肝匀浆MDA含量,使降低的肝匀浆GSH-Px、T-AOC活性升高(P<0.05).结论 苦参碱对小鼠免疫性肝损伤有明显的保护作用,其机制可能与增强抗氧化活性有关.  相似文献
5.
目的:观察健脾活血方对酒精复合内毒素脂多糖(lipopolysaccharide,LPS)诱导的肝损伤大鼠库普弗细胞活化信号通路的影响。方法:采用Lieber-Decarli酒精饮料饲养6周诱导的酒精性肝损伤模型,分设正常组,无酒精饮料组,酒精饮料组和酒精饮料加健脾活血方组,造模第3周起灌胃给药或蒸馏水至第6周末,各组再以LPS 10 mg/kg一次性灌胃,3.5 h后取材。检测血清丙氨酸氨基转移酶(alanine aminotransferase,ALT)活性和肝组织甘油三酯(triglyceride,TG)含量;HE染色观察大鼠肝组织病理改变;CD68免疫组化观察库普弗细胞活化状态;ELISA法检测门脉血浆肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)含量;Western-blotting方法检测肝组织TNF-α、磷酸化的IκB(phosphorylation-IκB,P-IκB)、Toll样受体4(Toll-like receptor 4,TLR4)、CD68蛋白表达。结果:经健脾活血方干预后,大鼠肝脏组织病理损伤减轻,肝组织TG含量以及血清ALT活性和门脉血浆TNF-α含量下降;同时,大鼠肝脏TNF-α、P-IκB、TLR4和CD68蛋白表达明显减轻。结论:健脾活血方对酒精复合LPS诱导的肝损伤大鼠CD68、TLR4、P-IκB和TNF-α具明显抑制作用。  相似文献
6.
目的比较熏香烟加气道内注入脂多糖(LPS)法和单纯熏香烟法建立慢性阻塞性肺病(COPD)大鼠模型的效果。方法8周龄Wistar大鼠24只,随机分为3组,每组8只。其中1组作健康对照,另2组分别进行熏香烟加气道内注入LPS和单纯熏香烟处理建立COPD模型。观察动物一般情况和肺组织病理学,测定肺组织平均内衬间隔(MLI)和平均肺泡数(MAN);检测外周血常规和支气管肺泡灌洗液(BALF)常规。结果两个模型组大鼠消瘦,伴有间歇咳嗽和气促,外周血和BALF中的白细胞总数及中性粒细胞百分比均较对照组明显增高(P<0.01);肺组织H-E染色显示两个模型组大鼠均具有慢性支气管炎和肺气肿的典型病变,MLI较对照组明显增高,而MAN较对照组明显下降(P<0.01),但两个模型组组间差异无统计学意义;熏香烟加气道内注入LPS组比单纯熏香烟组气道及肺组织的炎症浸润更明显,单纯熏香烟组主要表现为肺泡过度扩张。结论熏香烟加气道内注入LPS和单纯熏香烟两种方法均可成功制备大鼠COPD模型,其病理生理改变与人类COPD类似,前者比后者更符合COPD自然发病过程。  相似文献
7.
TLR4信号通路与炎性反应   总被引:3,自引:0,他引:3  
陈洁  姜虹 《医学综述》2009,15(19):2902-2904
Toll样受体(TLR)是一类天然免疫受体,最早发现其与果蝇胚胎背、腹侧的发育有关。随着研究的深入,哺乳动物体内也发现有类似同源性受体,并统一称TLR家族。TLR的分布十分广泛,可以识别某些病原体或其产物所共有的特定结构。TLR4是介导内毒素/脂多糖应答的主要受体,而TLR4/CD14信号通路是介导内毒素诱导的炎性反应的重要通路。营养性肥胖、动脉粥样硬化、心肌梗死、哮喘等所引起的非细菌性炎性反应也与TLR4相关。本文就TLR4信号通路与炎性反应的研究进展进行综述。  相似文献
8.
Background Mucus hypersecretion in the respiratory tract and goblet cell metaplasia in the airway epithelium contribute to the morbidity and mortality associated with airway inflammatory diseases. This study aimed to examine the effect and mechanisms of simvastatin on airway mucus hypersecretion in rats treated with lipopolysaccharide (LPS). Methods Mucus hypersecretion in rat airways was induced by intra-tracheal instillation of LPS. Rats treated with or without LPS were administered intra-peritoneally simvastatin (5 and 20 mg/kg) for 4 days. Expression of Muc5ac, RhoA and mitogen-activated protein kinases (MAPK) p38 in lung were detected by real-time polymerase chain reaction (PCR), immunohistochemistry or Western blotting. Tumor necrosis factor (TNF)-α and IL-8 in bronchoalveolar lavage fluid (BALF) were assayed by an enzyme-linked lectin assay and enzyme linked immunosorbent assay (ELISA). Results Simvastatin attenuated LPS-induced goblet cell hyperplasia in bronchial epithelium and Muc5ac hypersecretion at both the gene and protein levels in lung (P 〈0.05). Moreover, simvastatin inhibited neutrophil accumulation and the increased concentration of TNF-α and IL-8 in BALF follows LPS stimulation (P 〈0.05). The higher dose of simvastatin was associated with a more significant reduction in Muc5ac mRNA expression, neutrophil accumulation and inflammatory cytokine release. Simultaneously, the increased expression of RhoA and p38 MAPK were observed in LPS-treated lung (P 〈0.05). Simvastatin inhibited the expression of RhoA and p38 phosphorylation in lung following LPS stimulation (P 〈0.05). However, the increased expression of p38 protein in LPS-treated lung was not affected by simvastatin administration. Conclusions Simvastatin attenuates airway mucus hypersecretion and pulmonary inflammatory damage induced by LPS. The inhibitory effect of simvastatin on airway mucus hypersecretion may be through, at least in part, the suppression of neutrophil accumulation and  相似文献
9.
左旋咪唑与人胎盘脂多糖联合治疗复发性口腔溃疡42例   总被引:3,自引:0,他引:3  
杨志文 《实用新医学》2007,8(6):573-574
复发性口腔溃疡(ROU)是口腔粘膜最常见的溃疡类疾病,其发病率高达20左右。治疗方案虽多,但疗效大多不够理想。我院近年来应用左旋咪唑与人胎盘脂多糖联合治疗ROU42例,疗效满意。  相似文献
10.
0引言肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)是由激活的巨噬细胞分泌的炎性细胞因子,虽然TNF-a在免疫反应中起着非常重要的作用,但是当它过度表达和分泌的时候会引起一系列的疾病或病态体征,如中毒性休克、风湿性关节炎、急性坏死性胰腺炎。因此,抑制TNF-a的过度表达和分泌可能成  相似文献
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号