Lung cancer is the leading cause of cancer death worldwide,with large variation of the incidence and mortality across regions.Although the mortality of lung cancer has been decreasing,or steady in the US,it has been i...Lung cancer is the leading cause of cancer death worldwide,with large variation of the incidence and mortality across regions.Although the mortality of lung cancer has been decreasing,or steady in the US,it has been increasing in Asia for the past two decades.Smoking is the leading cause of lung cancer,and other risk factors such as indoor coal burning,cooking fumes,and infections may play important roles in the development of lung cancer among Asian never smoking women.The median age of diagnosis in Asian patients with lung cancer is generally younger than Caucasian patients,particularly among never-smokers.Asians and Caucasians may have different genetic susceptibilities to lung cancer,as evidenced from candidate polymorphisms and genome-wide association studies.Recent epidemiologic studies and clinical trials have shown consistently that Asian ethnicity is a favorable prognostic factor for overall survival in non-small cell lung cancer(NSCLC),independent of smoking status.Compared with Caucasian patients with NSCLC,East Asian patients have a much higher prevalence of epidermal growth factor receptor(EGFR) mutation(approximately 30% vs.7%,predominantly among patients with adenocarcinoma and never-smokers),a lower prevalence of K-Ras mutation(less than 10% vs.18%,predominantly among patients with adenocarcinoma and smokers),and higher proportion of patients who are responsive to EGFR tyrosine kinase inhibitors.The ethnic differences in epidemiology and clinical behaviors should be taken into account when conducting global clinical trials that include different ethnic populations.展开更多
Dyslipidemia, including low levels of high-density lipoprotein cholesterol (HDL-C), is a relatively well-established risk factor for cardiovascular disease. However, the independent association between changes in HDL-...Dyslipidemia, including low levels of high-density lipoprotein cholesterol (HDL-C), is a relatively well-established risk factor for cardiovascular disease. However, the independent association between changes in HDL-C and the subsequent risk of cardiovascular events has not been well studied. The retrospective cohort analysis was conducted to evaluate the association between changes in HDL-C and cardiovascular (CV) and/or cerebrovascular (CB) events among statin-treated patients. Patient demo-graphics, clinical characteristics, laboratory data, and CV/CB events, were collected from the UK General Practice Research Database. The association between the risk of an incident event and changes in patients’ HDL-C was estimated using multivariate Cox pro-portional hazards models. Among 17,923 statin-treated patients with an average follow-up of 1.9 years, there were 815 CV events and 220 CB events. The average change in HDL-C experienced was 0.4 mg/dL, ranging from 11 mg/dL average decrease in the lowest change quartile to 12 mg/dL average increase in the highest change quartile. CV events occurred at an average overall rate of 21 per 1000 person-years and 17 per 1000 person-years among individuals in the highest quartile of change in HDL-C levels. Fully adjusted Cox regression estimated a 6% decrease in hazards (HR, 0.94;95% CI, 0.90, 0.98) of a subsequent CV event associated with each 5 mg/dL increase in HDL-C. Similar results (HR: 0.95, 95% CI, 0.92, 0.98) were observed when assessing the association with changes in HDL-C and the composite outcome of CV/CB event. Among statin-treated patients from UK clinical practices, increases in HDL-C were associated with a significantly decreased relative risk of experiencing CV/CB events with a more pronounced effect on CV events. Therefore, a more aggressive treatment to increase HDL-C could benefit patients by reducing the risk of CV/CB events.展开更多
To compare the performance of four common methods of applying propensity scores： covariate adjustment, stratification, matching, and inverse probability of treatment weighting, in addressing issues of selection bias....To compare the performance of four common methods of applying propensity scores： covariate adjustment, stratification, matching, and inverse probability of treatment weighting, in addressing issues of selection bias. The linked Surveillance, Epidemiology, and End Results Medicare database was used in this study. We compared mortality of patients with localized prostate cancer, in two different scenarios. In Scenario 1, treatment effect on non-prostate cancer mortality were compared between patients with localized prostate cancer receiving active treatment （radical prostatectomy or radiation） and those only being observed. In Scenario 2, prostate cancer specific mortality was compared between localized prostate cancer patients with and without primary androgen deprivation therapy （ADT）. The known confounding factors of comorbidity （Scenario 1） or tumor grade （Scenario 2） were removed to evaluate the ability of each propensity score method to control for the selection bias caused by the presence of the factors. Matching yields slightly better control than the three other methods. None of the propensity score methods can eliminate bias caused by removing a known confounder.展开更多
Windbelt generators have been proposed as small, green power sources for battery charging applications. Some of the reported results lack detailed information about how key parameters influence the output power of the...Windbelt generators have been proposed as small, green power sources for battery charging applications. Some of the reported results lack detailed information about how key parameters influence the output power of the generator. In this work, we built prototypes with different architectures to study the voltage generation and power delivery as functions of belt tension, length, and electrical load at various wind speeds. We also studied the maximum power delivery conditions before the breakdown of the belt oscillation occurs. Our results are obtained from windbelt generators with two types of architectures： a conventional design with an adjustable belt that uses weight for tension control, and a revised design with a belt oscillation perpendicular to the coil axis. We have concluded that the breakdown of the belt oscillation at lower output resistances is a primary bottleneck that will limit windbelt systems to only very low power applications.展开更多
文摘Lung cancer is the leading cause of cancer death worldwide,with large variation of the incidence and mortality across regions.Although the mortality of lung cancer has been decreasing,or steady in the US,it has been increasing in Asia for the past two decades.Smoking is the leading cause of lung cancer,and other risk factors such as indoor coal burning,cooking fumes,and infections may play important roles in the development of lung cancer among Asian never smoking women.The median age of diagnosis in Asian patients with lung cancer is generally younger than Caucasian patients,particularly among never-smokers.Asians and Caucasians may have different genetic susceptibilities to lung cancer,as evidenced from candidate polymorphisms and genome-wide association studies.Recent epidemiologic studies and clinical trials have shown consistently that Asian ethnicity is a favorable prognostic factor for overall survival in non-small cell lung cancer(NSCLC),independent of smoking status.Compared with Caucasian patients with NSCLC,East Asian patients have a much higher prevalence of epidermal growth factor receptor(EGFR) mutation(approximately 30% vs.7%,predominantly among patients with adenocarcinoma and never-smokers),a lower prevalence of K-Ras mutation(less than 10% vs.18%,predominantly among patients with adenocarcinoma and smokers),and higher proportion of patients who are responsive to EGFR tyrosine kinase inhibitors.The ethnic differences in epidemiology and clinical behaviors should be taken into account when conducting global clinical trials that include different ethnic populations.
文摘Dyslipidemia, including low levels of high-density lipoprotein cholesterol (HDL-C), is a relatively well-established risk factor for cardiovascular disease. However, the independent association between changes in HDL-C and the subsequent risk of cardiovascular events has not been well studied. The retrospective cohort analysis was conducted to evaluate the association between changes in HDL-C and cardiovascular (CV) and/or cerebrovascular (CB) events among statin-treated patients. Patient demo-graphics, clinical characteristics, laboratory data, and CV/CB events, were collected from the UK General Practice Research Database. The association between the risk of an incident event and changes in patients’ HDL-C was estimated using multivariate Cox pro-portional hazards models. Among 17,923 statin-treated patients with an average follow-up of 1.9 years, there were 815 CV events and 220 CB events. The average change in HDL-C experienced was 0.4 mg/dL, ranging from 11 mg/dL average decrease in the lowest change quartile to 12 mg/dL average increase in the highest change quartile. CV events occurred at an average overall rate of 21 per 1000 person-years and 17 per 1000 person-years among individuals in the highest quartile of change in HDL-C levels. Fully adjusted Cox regression estimated a 6% decrease in hazards (HR, 0.94;95% CI, 0.90, 0.98) of a subsequent CV event associated with each 5 mg/dL increase in HDL-C. Similar results (HR: 0.95, 95% CI, 0.92, 0.98) were observed when assessing the association with changes in HDL-C and the composite outcome of CV/CB event. Among statin-treated patients from UK clinical practices, increases in HDL-C were associated with a significantly decreased relative risk of experiencing CV/CB events with a more pronounced effect on CV events. Therefore, a more aggressive treatment to increase HDL-C could benefit patients by reducing the risk of CV/CB events.
文摘To compare the performance of four common methods of applying propensity scores： covariate adjustment, stratification, matching, and inverse probability of treatment weighting, in addressing issues of selection bias. The linked Surveillance, Epidemiology, and End Results Medicare database was used in this study. We compared mortality of patients with localized prostate cancer, in two different scenarios. In Scenario 1, treatment effect on non-prostate cancer mortality were compared between patients with localized prostate cancer receiving active treatment （radical prostatectomy or radiation） and those only being observed. In Scenario 2, prostate cancer specific mortality was compared between localized prostate cancer patients with and without primary androgen deprivation therapy （ADT）. The known confounding factors of comorbidity （Scenario 1） or tumor grade （Scenario 2） were removed to evaluate the ability of each propensity score method to control for the selection bias caused by the presence of the factors. Matching yields slightly better control than the three other methods. None of the propensity score methods can eliminate bias caused by removing a known confounder.
文摘Windbelt generators have been proposed as small, green power sources for battery charging applications. Some of the reported results lack detailed information about how key parameters influence the output power of the generator. In this work, we built prototypes with different architectures to study the voltage generation and power delivery as functions of belt tension, length, and electrical load at various wind speeds. We also studied the maximum power delivery conditions before the breakdown of the belt oscillation occurs. Our results are obtained from windbelt generators with two types of architectures： a conventional design with an adjustable belt that uses weight for tension control, and a revised design with a belt oscillation perpendicular to the coil axis. We have concluded that the breakdown of the belt oscillation at lower output resistances is a primary bottleneck that will limit windbelt systems to only very low power applications.
