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31.
目的:观察慢性乙型肝炎患者乙型肝炎病毒e系统状态和复制指标在肝纤维化发生过程中的变化及其与血清纤维化标志的关系,探讨它们在肝纤维化发生过程中的作用及其可能的临床意义.方法:188例慢性乙型肝炎患者根据肝纤维化程度分为S0~S4期等5组,分别用定量PCR及放免法检测患者血清中HBV-DNA及肝纤维化标志透明质酸、Ⅳ型胶原、Ⅲ型前胶原和层粘连蛋白的含量;HBeAg和抗-HBe采用酶联免疫吸附法(ELISA)检测,并观察其在不同肝病理纤维化分期时的变化.结果:随着肝纤维化程度加重,血清HBV-DNA含量逐渐升高,从S1期开始显著增加(P<0.01);而HBeAg阳性率逐渐降低,S3、S4期较S0显著减少(P<0.05和P<0.01);抗-HBe阳性率呈相反的变化趋势,在S3和S4期的阳性率明显高于S0期(P<0.05和P<0.01).血清HBV-DNA( )HBeAg( )组血清纤维化标志最低,HBV-DNA(-)抗-HBe( )组最高,两者差异有显著性(P<0.01).结论:HBV复制和e系统状态的改变与肝纤维化程度密切相关,肝内病毒复制标志与血清纤维化标志联合检测,对于判断肝纤维化程度和指导抗病毒治疗有重要的价值.  相似文献   
32.
BACKGROUND: Abnormal glucose tolerance is a frequent co-morbidity in cystic fibrosis patients (CF), and is associated with a worse prognosis. The objectives are to investigate (a) the relative contribution of insulinopenia and insulin resistance (IR) for glucose tolerance and (b) the association between various glucose parameters and CF clinical status. METHODS: Oral glucose tolerance tests were performed in 114 consecutive CF patients not known to be diabetic as well as 14 controls similar for age and BMI. RESULTS: Abnormal glucose tolerance was found in 40% of patients with CF: 28% had impaired glucose tolerance (IGT) and 12% had new cystic fibrosis related diabetes (CFRD). Compared to control subjects, all CF patients were characterized by an increased glucose excursion (AUC). While reduced early insulin release characterised CF, IGT and CFRD patients also present IR thus both mechanisms significantly contribute to glucose tolerance abnormalities. Increased glucose AUC and reduced early insulin release but not glucose tolerance categories were associated with a reduced pulmonary function (FEV(1)). CONCLUSION: In CF, early insulin secretion defect but also IR contribute to glucose intolerance. Early in the course of the disease, increased glucose AUC and reduced early insulin secretion are more closely associated with a worse clinical status than conventional glucose tolerance categories.  相似文献   
33.
当归对肺纤维化大鼠肺形态学及胶原的影响   总被引:11,自引:0,他引:11  
目的 观察当归对博莱霉素所致的肺间质纤维化大鼠的肺形态学及胶原的影响 ,探讨其作用机制。方法  36只大鼠随机分为对照组、模型组及当归组。气管内注入博莱霉素复制大鼠肺间质纤维化模型 ,次日当归组每日腹腔内注射当归注射液 15 0mg/kg,于第 7及第 2 8天每组分别处死 6只大鼠 ,观察肺间质纤维化形成的病理变化及血清Ⅰ型胶原的含量。结果 当归能明显减轻肺泡炎和肺纤维化程度 ,与模型组比较 ,当归组血清Ⅰ型胶原含量于第 7、 2 8天明显降低 (P均 <0 0 5 )。结论 当归能减慢肺间质纤维化的进程 ,对肺间质纤维化有一定的保护作用。  相似文献   
34.
35.
Objective Sstudy effect of nuclear factor-κB ASOND on I type collagen expression and rat hepatic stellate cells(HSC)proliferation.Methods Rat HSCs were separated by affusing and digestingof Ⅳ type collagenenzyme and density acentric method.Lipid-mediated NF-κB p65 ASOND(0.001,0.01,0.1,1μmol/L)Was transferred into rat HSCs.Toxicity of HSCs caused by NF-κB p65 ASOND and activity of LDH were determined by trypan blue staining.Proliferation affection of transferring NF-κB p65 ASOND into HSCs was determined by MTT.In different concentration NF-κB p65 ASOND.expression of Ⅰ type collagen stimulated by 1mg/L TNF-αwas determined by RT-PCR and ELISA.Results After transfection of NF-κB p65 ASODN,expression of NF-κB protein in HSCs was decreasing.Toxicity experiment indicated that NF-κB p65 ASOND of different concentration(0.001,0.01,0.1 and 1.0 μmol/L)had no effect on HSCs livability and LDH activity(P<0.05).Four different concentration NF-κ B p65 ASOND could restrain HSCs proliferation stimulated by 1 mg/L TNF-α.The expression of I type collagen and mRNA stimulated by 1mg/LTNF-αwas increased,and had a positive correlation with concentration(P>0.05).Conclusion NF-κB p65 ASOND may depress NF-κB activity to restrain HSCs proliferation and Ⅰ type collagen expression,and reduce extracellular matrix.  相似文献   
36.
The aim of this study was to evaluate the influence of vascular endothelial growth factor (VEGF) on renal function and on development of interstitial fibrosis (IF) in renal allografts. Tubular and interstitial expressions of VEGF and TNF-α, and density of macrophages in the interstitium were examined in 92 patients with nonrejected kidneys, acute rejection (AR), chronic allograft nephropathy (CAN), borderline changes (BC) and acute cyclosporin A (CsA) toxicity. Follow-up biopsy specimens from patients with AR and BC were evaluated for development of IF. A significant difference in tubular and interstitial VEGF expressions was found between patients with AR, BC, CAN and CsA toxicity (p < 0.001). Macrophage infiltration was positively correlated with VEGF and TNF-α expressions (p < 0.001). VEGF expression increased with increasing expression of TNF-α (p < 0.001). Renal function in first 6 months after initial biopsy was better in patients with marked tubular VEGF expression (p < 0.01); however, in follow-up, development of IF and graft loss was found earlier in these patients (p < 0.01 and p < 0.05, respectively). Increased renal VEGF expression has protective properties immediately following renal allograft but allows for increased risk of early IF, and therefore poor graft outcome in the long term.  相似文献   
37.
BACKGROUND: Oral submucous fibrosis (OSF) is a chewing habit-related pre-cancerous condition of the oral mucosa affecting predominantly south Asians. It is histopathologically characterized by epithelial atrophy and fibrosis of the subepithelial connective tissue. Fibrosis extends all the way into the muscle layer, leading to difficulty in mouth opening. However, the dynamics of extracellular matrix (ECM) remodeling with OSF progression is largely unknown. METHODS: Forty biopsy specimens of OSF and 10 of normal buccal mucosa were examined for expression/deposition modes of eight ECM molecules by histochemistry, immunohistochemistry, and in situ hybridization. RESULTS: In the early stage of OSF, tenascin, perlecan, fibronectin, collagen type III were characteristically enhanced in the lamina propria and the submucosal layer. In the intermediate stage, the ECM molecules mentioned above and elastin were extensively and irregularly deposited around muscle fibers. In the advanced stage, such ECM depositions decreased and were entirely replaced with collagen type I only. Their gene expression levels varied with progression of fibrosis, but the mRNA signals were confirmed in fibroblasts in the submucosal fibrotic areas. CONCLUSIONS: The results indicate that the ECM remodeling steps in OSF are similar to each phase of usual granulation tissue formation. Restricted mouth opening may be a result of loss of variety of ECM molecules including elastin into the homogeneity of collagen type I replacing muscle fibers.  相似文献   
38.
39.
SUMMARY: The effect of mild acute tubular injury on the progression of tubulointerstitial fibrosis was studied in pair-fed uninephrectomized male Wistar rats with established adriamycin nephrosis ( n = 34). Rats were stratified into three groups according to endogenous creatinine clearance (CrCl), proteinuria (Upr) and body weight (BW): (i) group 1 (Fe, n = 12) received a single intraperitoneal injection of ferric nitrilotriacetate (5 mg Fe/kg BW); (ii) group 2 (G, n = 10) three daily subcutaneous injections of gentamicin (60 mg/kg BW) and; (iii) group 3 (C, n = 12) saline injections. Serial CrCl (day 2, day 5, weeks 2, 4, 6 and 8) and renal histology (week 8) were examined following administration of nephrotoxin. CrCl was reduced on d2 (Fe: 0.78 ± 0.23 mL/min; mean ± SD) and day 5 (G: 0.91 ± 0.36 mL/min) as compared with C (1.22 ± 0.12 mL/min; P <0.05). There was no change in the serum creatinine and functional recovery occurred by d5 (Fe) and week 2 (G). Upr decreased transiently in G at week 2 (G: 482 ± 208 mg/day vs C: 716 ± 233; P = 0.05) despite similar food intake, baseline Upr and CrCl. At week 8, CrCl in Fe (0.84 ± 0.40 mL/min) was similar to C (0.84 ± 0.58 mL/min), whereas in G it remained stable (1.27 ± 0.39 mL/min; P <0.05). By morphometric analysis, mean relative interstitial volume (RIV) and glomerulosclerosis (GS) in Fe (RIV: 28.5 ± 13.4%; GS: 10.3 ± 12.3%) was no different to C (RIV: 24.5 ± 12.5%; GS: 20.9 ± 20.0%), whereas both parameters were reduced in G (RIV: 14.1 ± 8.1%; GS: 4.0 ± 4.8%; P <0.05). Mild gentamicin nephrotoxicity therefore reduced the progression of adriamycin nephrosis. the mechanism of this finding is unclear, but it may relate to altered glomerular and tubular cell handling of protein.  相似文献   
40.
目的 :研究口腔黏膜下纤维性变中S10 0蛋白的表达水平及其与正常口腔黏膜上皮、异常增生上皮的比较。方法 :应用免疫组织化学 (SP)法 ,检测 10例口腔黏膜下纤维性变、10例上皮异常增生、8例正常口腔黏膜上皮S10 0蛋白表达水平 ,并作对比研究。结果 :S10 0蛋白在正常口腔黏膜上皮中无表达 ,口腔黏膜下纤维性变上皮中和异常增生上皮中S10 0的阳性表达率为 5 0 %,后两者的阳性表达率明显高于正常黏膜组上皮 (P <0 .0 5 ) ;口腔黏膜下纤维性变组与异常增生上皮组比较 ,差异无显著性 (P >0 .0 5 )。结论 :口腔黏膜下纤维性变发生发展与S10 0蛋白过表达密切相关 ,S10 0蛋白表达强度与异常增生上皮表达强度一致。  相似文献   
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