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991.
Zhao H Bai X Nie XH Wang JT Wang XX Pang NN Li YJ Ma XM Wen H Ding JB 《中国寄生虫学与寄生虫病杂志》2012,30(1):32-35
目的观察泡球蚴感染小鼠肝脏中白细胞介素-10(IL-10)和转化生长因子-β(TGF-β1)的动态变化。方法将60只雌性BALB/c小鼠随机均分为实验组和对照组,实验组腹腔注射活原头节悬液0.2ml(约含400个原头节),对照组腹腔注射等量生理盐水,分别于接种后2、8、30、90、180和360d各处死5只小鼠,取肝组织进行病理学检查,并用免疫组织化学法检测肝组织中IL-10和TGF-β1的表达情况。结果实验组小鼠,腹腔和肝小叶出现多处直径不等的小囊泡,随感染时间的延长逐渐增多增大,与周围肝组织分界不明显。HE染色显示,实验组小鼠肝脏出现炎症细胞浸润,泡球蚴纤维囊壁与肝细胞和囊壁之间炎症反应带的形成等不同程度的病理改变;对照组小鼠肝小叶结构完整,偶见少量炎症细胞浸润,肝细胞胞浆疏松化和脂肪变性。实验组小鼠肝组织表达水平随着泡球蚴感染时间的延长而逐渐上升,感染后90d,实验组小鼠肝组织中IL-10和TCF-β1的表达水平均达高峰,细胞阳性率分别为(16.39±1.73)%和(23.69±2.29)%,与对照组比较[(1.09±0.10)%和(0.98±0.09)%]差异均有统计学意义(P<0.01),而且之后均维持在较高水平。结论小鼠泡球蚴感染中晚期,IL-10和TGF-β1表达水平均提高,其免疫抑制作用不利于清除和控制肝脏中泡球蚴。 相似文献
992.
目的了解无锡地区散养鸡的弓形虫感染状况。方法应用ELISA方法调查无锡地区309例散养鸡的弓形虫抗原、抗体阳性率,并与150例集约化养殖鸡的弓形虫感染率进行比较,其中一项阳性即视为弓形虫感染阳性。结果 309例散养鸡中,抗原阳性29例,阳性率为9.39%;抗体阳性53例,阳性率为17.15%;双阳性13例,双阳性率为4.21%;散养鸡总体阳性率为22.33%。集约化养殖鸡总体弓形虫感染率为2.67%。散养鸡感染率显著高于集约化养殖鸡感染率(χ2=29.19,P<0.01)。结论无锡地区散养鸡群弓形虫感染率较高,应引起重视。 相似文献
993.
目的报道机械瓣膜置换术后患者左侧旁道射频消融的经验。方法分析瓣膜置换术后患者左侧旁道射频消融的影像学和导管操作的特点,以及消融术前后的注意事项。结果 3例患者(男1例,女2例),年龄为32,46,46岁,分别为二尖瓣置换术后(2例)和主动脉瓣与二尖瓣联合换瓣术后(1例),均行心内电生理检查诊断为经左侧旁道折返的顺向型房室折返性心动过速,分别经主动脉逆行法(2例)和穿房间隔法(1例)射频消融治疗成功。结论换瓣术后患者的左侧旁道可考虑经导管射频消融治疗。 相似文献
994.
995.
Diao TJ Chen X Deng LH Chen HX Liang Y Zhao XD Wang QH Yuan WS Gao BC Ye Y 《World journal of gastroenterology : WJG》2012,18(25):3310-3316
AIM: To evaluate immunological protection of nitric oxide (NO) in hepatopulmonary syndrome and probable mechanisms of ischemia-reperfusion (IR) injury in rat liver transplantation.METHODS: Sixty-six healthy male Wistar rats were randomly divided into three groups (11 donor/recipient pairs). In group II, organ preservation solution was lactated Ringer’s solution with heparin 10 000/μL at 4 °C. In groups I and III, the preservation solution added, respectively, L-arginine or NG-L-arginine methyl ester (L-NAME) (1 mmol/L) based on group II, and recipients were injected with L-arginine or L-NAME (50 mg/kg) in the anhepatic phase. Grafted livers in each group were stored for 6 h and implanted into recipients. Five rats were used for observation of postoperative survival in each group. The other six rats in each group were used to obtain tissue samples, and executed at 3 h and 24 h after transplantation. The levels of alanine aminotransferase (ALT), tumor necrosis factor (TNF)-α and NO metabolites (NOx) were detected, and expression of NO synthase, TNF-α and intercellular adhesion molecule 1 (ICAM-1) was examined by triphosphopyridine nucleotide diaphorase histochemical and immunohistochemical staining.RESULTS: By supplementing L-arginine to strengthen the NO pathway, a high survival rate was achieved and hepatic function was improved. One-week survival rate of grafted liver recipients in group I was significantly increased (28.8 ± 36.6 d vs 4 ± 1.7 d, P < 0.01) as compared with groups II and III. Serum levels of ALT in group I were 2-7 times less than those in groups II and III (P < 0.01). The cyclic guanosine monophosphate (cGMP) levels in liver tissue and NOx in group I were 3-4 times higher than those of group II after 3 h and 24 h reperfusion, while in group III, they were significantly reduced as compared with those in group II (P < 0.01). The levels of TNF-α in group I were significantly lower than in group II after 3 h and 24 h reperfusion (P < 0.01), while being significantly higher in group III than group II (P < 0.01). Histopathology revealed more severe tissue damage in graft liver and lung tissues, and a more severe inflammatory response of the recipient after using NO synthase inhibitor, while the pathological damage to grafted liver and the recipient’s lung tissues was significantly reduced in group I after 3 h and 24 h reperfusion. A small amount of constitutive NO synthase (cNOS) was expressed in liver endothelial cells after 6 h cold storage, but there was no expression of inducible NO synthase (iNOS). Expression of cNOS was particularly significant in vascular endothelial cells and liver cells at 3 h and 24 h after reperfusion in group II, but expression of iNOS and ICAM-1 was low in group I. There was diffuse strong expression of ICAM-1 and TNF-α in group III at 3 h after reperfusion.CONCLUSION: The NO/cGMP pathway may be critical in successful organ transplantation, especially in treating hepatopulmonary syndrome during cold IR injury in rat orthotopic liver transplantation. 相似文献
996.
AIM: To investigate the efficacy and safety of combined antiviral and immunosuppressant therapy in adult hepatitis B virus-associated glomerulonephritis (HBV-GN) patients.METHODS: A computerized literature search was carried out in the PubMed database, Embase, the Cochrane Library, Chinese BioMedical Literature on disc, Chinese Medical Current Contents, Chinese National Knowledge Infrastructure, Wanfang and VIP (Chinese Technological Journal of Database) to collect articles between June 1980 and December 2010 on therapy with immunosuppressants, e.g., glucorticosteroids, mycophenolate mofetil and leflunomide, combined with antivirals, e.g., interferon, lamivudine, entecavir and adefovir dipivoxil, in adult HBV-GN patients. The primary outcomes were remission of proteinuria, clearance of HBV e-antigen, and elevation of serum albumin. The secondary outcomes were blood levels of alanine aminotransferase, serum creatinine, and HBV-DNA titer. Meta-analysis was performed using Review Manager 5.1. Fixed or random effect models were employed to combine the results after a heterogeneity test. The effects of the combined therapy were analyzed for different doses of glucorticosteroid and different types of HBV-GN.RESULTS: Twelve clinical trials with 317 patients were included. A significantly higher incidence of HBV-GN was found in male patients (relative risk = 2.40, 95% CI: 1.98-2.93). Combined therapy reduced the proteinuria significantly with a mean difference of 4.19 (95% CI: 3.86-4.53) and increased the serum albumin concentration significantly with a mean difference of -11.95 (95% CI: -12.97-10.93) without significant alterations of liver function (mean difference: 4.62, 95% CI: -2.55-11.79) and renal function (mean difference: 10.29, 95% CI: 0.14-20.45). No significant activation of HBV-DNA replication occurred (mean difference: 0.12, 95% CI: -0.37-0.62). There was no significant difference between the high dose glucorticosteroid group and the low dose glucorticosteroid group in terms of proteinuria remission (P = 0.76) and between different pathological types of HBV-GN [membranous glomerulonephritis (MN) vs mesangial proliferative glomerulonephritis, P = 0.68; MN vs membranoproliferative glomerulonephritis, P = 0.27].CONCLUSION: Combined antiviral and immunosuppressant therapy can improve the proteinuria in HBV-GN patients without altering HBV replication or damaging liver and renal functions. 相似文献
997.
目的:分析聚乙二醇干扰素-2a(peginterferon-2a,Peg-IFN-2a)治疗HBeAg阳性慢性乙型肝炎应答不佳者联合阿德福韦酯(adefovirdipivoxil,ADV)治疗48 wk的疗效、安全性,并评价48 wk疗效预测指标.方法:140例患者初始均接受Peg-IFN-2a每周1次皮下注射单药治疗,根据24 wk时HBVDNA水平进行分组.A组90例患者治疗24 wk时HBV DNA≥2.0×103IU/mL且HBV DNA下降≥2 log10 IU/mL,其中A1组45例患者加用ADV治疗至48 wk,A2组45例患者继续Peg-IFN-2a单药治疗至48 wk;B组50例患者治疗24 wk时HBV DNA<2.0×103IU/mL,继续Peg-IFN-2a治疗至48 wk.比较各组基线及治疗中HBV DNA、HBsAg、HBeAg及ALT水平.结果:治疗36、48 wk时HBV DNA转阴率B组>A1组>A2组(P<0.01).治疗36 wk时HBV DNA下降值B组>A1组>A2组(P<0.01).48 wk时HBV DNA下降值A1组>A2组(P<0.01),A1、B组之间差异无统计学意义.治疗24-48 wk期间,A1组HBeAg血清转换率升高幅度>A2组和B组(P<0.01).治疗48 wk时HBsAg下降A1组4例、A2组1例、B组2例.治疗36、48 wk时A1与A2、B组ALT复常率差异无统计学意义.A1组治疗48 wk时HBV DNA阴转与治疗36 wk HBVDNA下降值有关.治疗36 wk时HBV DNA较基线下降值对48 wk时HBV DNA阴转的阳性预测值为90.5%,较24 wk时下降值对48 wk时HBV DNA阴转的阳性预测值为95.7%.结论:Peg-IFN-2a治疗HBeAg阳性慢性乙型肝炎应答不佳者联合ADV治疗提高病毒应答、HBeAg血清转换率,其中治疗36 wk时HBV DNA下降值可预测48 wk疗效. 相似文献
998.
目的:研究瘦素、瘦素受体(obesity receptor,OB-R)以及PI3-K/Akt信号通路在非酒精性脂肪肝(nonalcoholic fatty liver disease,NAFLD)患者体内的表达.方法:应用免疫组织化学方法研究30例NAFLD患者及对照组肝组织中瘦素,OB-R,PI3-K(p85)及Akt的表达以及其相关性.同时检测空腹血糖、总胆固醇、甘油三酯、C肽和血清瘦素水平等.结果:NAFLD患者肝组织中瘦素,OB-R和PI3-K显著高于对照组(P<0.05),且与血清瘦素水平成正相关.NAFLD患者肝组织中Akt的表达显著低于对照组(P<0.05).此外,PI3-K的表达与瘦素(r=0.365,P<0.05)呈正相关,但与Akt呈负相关(r=-0.854,P<0.01).结论:瘦素的过度表达不能活化NAFLD患者的Akt,瘦素/PI3-K激活Akt的缺陷可能是NAFLD患者瘦素抵抗的一种新机制. 相似文献
999.
肝内胆管结石合并胆管癌 总被引:1,自引:0,他引:1
肝内胆管结石在东亚地区是较为常见的疾病,是肝内胆管癌最主要的病因之一.胆管内结石对胆管壁的长期刺激,结石引起的胆管狭窄梗阻造成胆汁滞留及同时伴发的细菌感染等生物因素的慢性刺激,导致胆管壁的慢性增生性炎症,进而引起胆管上皮的不典型增生和上皮化生,发生癌变.本文主要对肝内胆管结石合并胆管癌的病因、临床表现、影像学诊断和病理特点、治疗方式等方面进行阐述.肝内胆管结石合并胆管癌的诊断和治疗均是对外科医生的巨大挑战. 相似文献
1000.
急性肝损伤肝脏炎症环境对骨髓间充质干细胞移植疗效的影响 总被引:1,自引:0,他引:1
目的:探讨猪急性肝损伤肝脏内不同程度炎症反应对移植骨髓间充质干细胞(mesenchymal stem cells,MSCs)存活率和疗效的影响.8):对照组和移植组.每组均按照低浓度D氨基半乳糖胺(D-gal,0.25 g/kg)、高浓度D氨基半乳糖胺(D-gal,0.35 g/kg)给药,分别建立2种急性肝损伤模型,诱导24 h后,对照组动物门静脉注射生理盐水40 mL,移植组动物门静脉移植40 mL PBS(约8×107同种异体GFP-MSCs).2 wk内观察猪肝功能变化、病理变化、血清炎症指标和移植MSCs定植存活情况.结果:低浓度D-gal组血清IL-1、TNF-α水平明显低于高浓度D-gal组,差异有显著性.低浓度D-gal移植组与低浓度D-gal对照组比较,ALT、TB和NH3在早期有显著差异(D2:232.6±57.6 vs 334.4±42.3,12.2±3.3 vs 16.0±1.2,79.7±9.3 vs 127.8±28.2,P<0.05);高浓度D-gal移植组与高浓度D-gal对照组比较,肝功能指标有改善,但无显著意义.低浓度D-gal移植组MSCs定植存活率和肝细胞增殖率显著高于高浓度D-gal移植组.结论:骨髓间充质干细胞移植治疗肝损伤的疗效在很大程度上取决于肝脏炎症反应的程度,炎症反应越严重,移植细胞越不易存活;相反,较低的体内炎症环境有益于MSCs定植、存活和肝细胞再生. 相似文献