AIM： To evaluate serum TIMP-1 level and the correlation between TIMP-1 expression and liver fibrosis in immuneinduced and CCL4-induced liver fibrosis models in rats. METHODS： Immune-induced and CCL4-induced liver fi...AIM： To evaluate serum TIMP-1 level and the correlation between TIMP-1 expression and liver fibrosis in immuneinduced and CCL4-induced liver fibrosis models in rats. METHODS： Immune-induced and CCL4-induced liver fibrosis models were established by dexamethasone （0.01 mg） and CCL4 respectively. Serum TIMP-1 level was detected with ELISA, while histopathological grade of liver biopsy was evaluated. Spearman rankcorrelation test was used to analyse the difference of the correlation between the TIMP-1 expression and hepatic fibrosis in the two fibrosis models. Furthermore,in situ hybridization was used to determine the expression difference of TIMP-1 mRNA in the two models. RESULTS： Positive correlation existed between serum TIMP-1 level of immune induced group and the histopathological stages of fibrosis liver of corresponding rats （Spearman rank-correlation test, rs = 0.812, P 0.05）, and the positive in situ hybridization signal of TIMP-1 mRNA was strong. In CCL4-induced liver fibrosis model, the correlation between the serum TIMP-1 level and the severity of hepatic fibrosis was not statistically significant（Spearman rank-correlation test, rs = 0.229, P 〉 0.05）. And compared with immune-induced model, the positivein situ hybridization signal of TIMP-1 mRNA was weaker, while the expression variation was higher in hepatic fibrosis of the same severity. CONCLUSION： The correlations between TIMP-1 expression and liver fibrosis in two rat liver fibrosis models are different. In immune-induced model, serum TIMP-1 level could reflect the severity of liver fibrosis, while in CCL4-induced model, the correlation between the serum TIMP-1 level and the severity of hepatic fibrosis was not statistically significant.展开更多
Hot deformation behaviors and microstructure evolution of Ti-3Al-5Mo-4Cr-2Zr-1Fe(Ti-35421)alloy in theβsingle field are investigated by isothermal compression tests on a Gleeble-3500 simulator at temperatures of 820-...Hot deformation behaviors and microstructure evolution of Ti-3Al-5Mo-4Cr-2Zr-1Fe(Ti-35421)alloy in theβsingle field are investigated by isothermal compression tests on a Gleeble-3500 simulator at temperatures of 820-900°C and strain rates of 0.001-1 s^(-1).The research results show that discontinuous yield phenomenon and rheological softening are affected by the strain rates and deformation temperatures.The critical conditions for dynamic recrystallization and kinetic model of Ti-35421 alloy are determined,and the Arrhenius constitutive model is constructed.The rheological behaviors of Ti-35421 alloys aboveβphase transformation temperature are predicted by the constitutive model accurately.The EBSD analysis proves that the deformation softening is controlled by dynamic recovery and dynamic recrystallization.In addition,continuous dynamic recrystallization is determined during hot deformation,and the calculation model for recrystallization grain sizes is established.Good linear dependency between the experimental and simulated values of recrystallized grain sizes indicates that the present model can be used for the prediction of recrystallized grain size with high accuracy.展开更多
Di-p-methoxyphenyl-2, 2-dinitroethylene reacts with 1-benzyl-1, 4-dihydronico- tinamide (BNAH) in deaerated acetonitrile to give 1, 1-di-p-methoxyphenyl-2, 2-dinitroethane, while 1, 1-di-O-methoxyphenyl-2, 2-dinitroet...Di-p-methoxyphenyl-2, 2-dinitroethylene reacts with 1-benzyl-1, 4-dihydronico- tinamide (BNAH) in deaerated acetonitrile to give 1, 1-di-p-methoxyphenyl-2, 2-dinitroethane, while 1, 1-di-O-methoxyphenyl-2, 2-dinitroethylene fails to react with BNAH under the same conditions, which provides evidence for a concerted electron-hydrogen atom transfer mechanism.展开更多
基金Supported by the Postdoctoral Science Foundation of China, No.1999-10the Science and Technology Foundation of Shaanxi Province, China, No. 2003K10G63
文摘AIM： To evaluate serum TIMP-1 level and the correlation between TIMP-1 expression and liver fibrosis in immuneinduced and CCL4-induced liver fibrosis models in rats. METHODS： Immune-induced and CCL4-induced liver fibrosis models were established by dexamethasone （0.01 mg） and CCL4 respectively. Serum TIMP-1 level was detected with ELISA, while histopathological grade of liver biopsy was evaluated. Spearman rankcorrelation test was used to analyse the difference of the correlation between the TIMP-1 expression and hepatic fibrosis in the two fibrosis models. Furthermore,in situ hybridization was used to determine the expression difference of TIMP-1 mRNA in the two models. RESULTS： Positive correlation existed between serum TIMP-1 level of immune induced group and the histopathological stages of fibrosis liver of corresponding rats （Spearman rank-correlation test, rs = 0.812, P 0.05）, and the positive in situ hybridization signal of TIMP-1 mRNA was strong. In CCL4-induced liver fibrosis model, the correlation between the serum TIMP-1 level and the severity of hepatic fibrosis was not statistically significant（Spearman rank-correlation test, rs = 0.229, P 〉 0.05）. And compared with immune-induced model, the positivein situ hybridization signal of TIMP-1 mRNA was weaker, while the expression variation was higher in hepatic fibrosis of the same severity. CONCLUSION： The correlations between TIMP-1 expression and liver fibrosis in two rat liver fibrosis models are different. In immune-induced model, serum TIMP-1 level could reflect the severity of liver fibrosis, while in CCL4-induced model, the correlation between the serum TIMP-1 level and the severity of hepatic fibrosis was not statistically significant.
基金the financial supports from the National Natural Science Foundation of China (Nos. 52001163, 52075237)the Primary Research and Development Plan of Jiangsu Province, China (No. BE2019119)
文摘Hot deformation behaviors and microstructure evolution of Ti-3Al-5Mo-4Cr-2Zr-1Fe(Ti-35421)alloy in theβsingle field are investigated by isothermal compression tests on a Gleeble-3500 simulator at temperatures of 820-900°C and strain rates of 0.001-1 s^(-1).The research results show that discontinuous yield phenomenon and rheological softening are affected by the strain rates and deformation temperatures.The critical conditions for dynamic recrystallization and kinetic model of Ti-35421 alloy are determined,and the Arrhenius constitutive model is constructed.The rheological behaviors of Ti-35421 alloys aboveβphase transformation temperature are predicted by the constitutive model accurately.The EBSD analysis proves that the deformation softening is controlled by dynamic recovery and dynamic recrystallization.In addition,continuous dynamic recrystallization is determined during hot deformation,and the calculation model for recrystallization grain sizes is established.Good linear dependency between the experimental and simulated values of recrystallized grain sizes indicates that the present model can be used for the prediction of recrystallized grain size with high accuracy.
文摘Di-p-methoxyphenyl-2, 2-dinitroethylene reacts with 1-benzyl-1, 4-dihydronico- tinamide (BNAH) in deaerated acetonitrile to give 1, 1-di-p-methoxyphenyl-2, 2-dinitroethane, while 1, 1-di-O-methoxyphenyl-2, 2-dinitroethylene fails to react with BNAH under the same conditions, which provides evidence for a concerted electron-hydrogen atom transfer mechanism.
