During the last 10 years, a lot of interests have been devoted to the so-called CDC （colossal dielectric constant） materials. The first materials exhibiting this behavior were the perovskite-based ceramics on the CC...During the last 10 years, a lot of interests have been devoted to the so-called CDC （colossal dielectric constant） materials. The first materials exhibiting this behavior were the perovskite-based ceramics on the CCTO （CaCuaTi4012） composition. Relative dielectric permittivity can attain values up to （or even larger than） 105. Nevertheless, their dielectric losses are too high, the lower values ranging 10%, in a narrow frequency range, thus limiting their applications. The underlying physical mechanisms at the origin of the CDC are still under study. The analysis of broadband impedance spectroscopy measurements leads most of the authors to propose an interracial polarization mechanism （at the electrodes or at internal barriers）, there is a limited number of complementary electrical characterization techniques, which, up to now, comfort the proposed interracial polarization mechanisms. In the present work, I-V and time-domain polarization are used to characterize these materials. One of the main results is the observation of a non-symmetrical response of these materials related to the direction of the polarization. These results are observed for both macroscopic level on bulk polycrystalline material and within individual grains of the same samples. These results do not fit current accepted models for polarization for CDC materials.展开更多
OBJECTIVE:To compare the long-term effectiveness of compound Ruanjianhugan(RJH)tablets and interventional therapy(IT) in patients after resection of small hepatocellular carcinoma(HCC).METHODS:A retrospective study wa...OBJECTIVE:To compare the long-term effectiveness of compound Ruanjianhugan(RJH)tablets and interventional therapy(IT) in patients after resection of small hepatocellular carcinoma(HCC).METHODS:A retrospective study was conducted in 399 patients after resection of small HCC who were admitted between January 1987 and December 2008 in the Department of Hepatobiliary Surgery and Center of Minimlly Invasive Surgery,First Affiliated Hospital of Guangxi Medical University.Four groups were based on different therapy modes:a TCM-only(TCMO) group,a TCM combined with interventional therapy(TCM-IT) group,an interventional therapy-only(ITO) group,and a simple operation(SO) group.Prognostic factors were correlated with overall survival(OS) and OS rates were calculated with the Kaplan-Meier method,and multivariate analyses for factors affecting survival were evaluated by the Cox proportional hazard model.RESULTS:The median OS was 151.20 months in the TCM-IT group,43.87 months in the ITO group,and 20.77 months in the SO group.All survival rates of the TCMO group were higher than those of the other three groups(>50%).The 5-,10-,and 15-year OS in the TCMO and ITO patients were 83.94%,45.50%,and 71.22% and 33.34%,55.58%,and 9.26%,respectively(risk ratio,0.209;95% confidence interval,0.126-0.347;P=0.000).Multivariate analysis revealed that the independent risk factors were therapy mode(P=0.000),sex(P=0.005),family history(P=0.011),TNM Classification of Malignant Tumor staging(P=0.000),medical care-seeking behavior(P=0.021),and maximum diameter(P=0.030).CONCLUSION:Long-term oral use of compound RJH tablets may improve OS for small HCC after resection compared with IT.展开更多
文摘During the last 10 years, a lot of interests have been devoted to the so-called CDC （colossal dielectric constant） materials. The first materials exhibiting this behavior were the perovskite-based ceramics on the CCTO （CaCuaTi4012） composition. Relative dielectric permittivity can attain values up to （or even larger than） 105. Nevertheless, their dielectric losses are too high, the lower values ranging 10%, in a narrow frequency range, thus limiting their applications. The underlying physical mechanisms at the origin of the CDC are still under study. The analysis of broadband impedance spectroscopy measurements leads most of the authors to propose an interracial polarization mechanism （at the electrodes or at internal barriers）, there is a limited number of complementary electrical characterization techniques, which, up to now, comfort the proposed interracial polarization mechanisms. In the present work, I-V and time-domain polarization are used to characterize these materials. One of the main results is the observation of a non-symmetrical response of these materials related to the direction of the polarization. These results are observed for both macroscopic level on bulk polycrystalline material and within individual grains of the same samples. These results do not fit current accepted models for polarization for CDC materials.
基金Supported by Grants from the 11th National Key Technology R&D Program(No.2006BAI04A06)E-institutes of Shanghai Municipal Education Commission Support Program(No.E03008)
文摘OBJECTIVE:To compare the long-term effectiveness of compound Ruanjianhugan(RJH)tablets and interventional therapy(IT) in patients after resection of small hepatocellular carcinoma(HCC).METHODS:A retrospective study was conducted in 399 patients after resection of small HCC who were admitted between January 1987 and December 2008 in the Department of Hepatobiliary Surgery and Center of Minimlly Invasive Surgery,First Affiliated Hospital of Guangxi Medical University.Four groups were based on different therapy modes:a TCM-only(TCMO) group,a TCM combined with interventional therapy(TCM-IT) group,an interventional therapy-only(ITO) group,and a simple operation(SO) group.Prognostic factors were correlated with overall survival(OS) and OS rates were calculated with the Kaplan-Meier method,and multivariate analyses for factors affecting survival were evaluated by the Cox proportional hazard model.RESULTS:The median OS was 151.20 months in the TCM-IT group,43.87 months in the ITO group,and 20.77 months in the SO group.All survival rates of the TCMO group were higher than those of the other three groups(>50%).The 5-,10-,and 15-year OS in the TCMO and ITO patients were 83.94%,45.50%,and 71.22% and 33.34%,55.58%,and 9.26%,respectively(risk ratio,0.209;95% confidence interval,0.126-0.347;P=0.000).Multivariate analysis revealed that the independent risk factors were therapy mode(P=0.000),sex(P=0.005),family history(P=0.011),TNM Classification of Malignant Tumor staging(P=0.000),medical care-seeking behavior(P=0.021),and maximum diameter(P=0.030).CONCLUSION:Long-term oral use of compound RJH tablets may improve OS for small HCC after resection compared with IT.
