AIM:To study the incidence and survival rate of stomach cancer(SC)and its associated factors in a high risk population in Chile. METHODS:The population-based cancer registry of Valdivia,included in the International A...AIM:To study the incidence and survival rate of stomach cancer(SC)and its associated factors in a high risk population in Chile. METHODS:The population-based cancer registry of Valdivia,included in the International Agency for Research on Cancer system,covers 356 396 residents of Valdivia Province,Southern Chile.We studied all SC cases entered in this Registry during 1998-2002 (529 cases).Population data came from the Chilean census(2002).Standardized incidence rates per 100 000 inhabitants(SIR)using the world population, cumulative risk of developing cancer before age 75, and rate ratios by sex,age,ethnicity and social factors were estimated.Relative survival(EdererⅡmethod) and age-standardized estimates(Brenner method) were calculated.Specific survival rates(Kaplan-Meier) were measured at 3 and 5 years and survival curves were analyzed with the Logrank and Breslow tests. Survival was studied in relation to demographics, clinical presentation,laboratory results and medical management of the cases.Those variables significantly associated with survival were later included in a Cox multivariate model. RESULTS:Between 1998 and 2002,529 primary gastric cancers occurred in Valdivia(crude incidence rate 29.2 per 100000 inhabitants).Most cases were male(69.0%), residents of urban areas(57.5%)and Hispanic(83.2%), with a low education level(84.5%<8 school years). SC SIR was higher in men than women(40.8 and 14.8 respectively,P<0.001),risk factors were low education RR 4.4(95%CI:2.9-6.8)and 1.6,(95%CI:1.1-2.1) for women and men respectively and Mapuche ethnicity only significant for women(RR 2.2,95%CI:1.2-3.7).Of all cases,76.4%were histologically confirmed,11.5% had a death certificate only(DCO),56.1%were TNM stageⅣ;445 cases(84.1%)were eligible for survival analysis,all completed five years follow-up;42 remained alive,392 died of SC and 11 died from other causes. Specific 5-year survival,excluding cases with DCO,was 10.6%(95%CI:7.7-13.5);5-year relative survival rate was 12.3%(95%CI:9.1-16.1),men 10.9%(95%CI: 7.4-15.2)and women 16.1%(95%CI:9.5-24.5).Fiveyear specific survival was higher for patients aged<55 years(17.3%),with intestinal type of cancer(14.6%), without metastasis(22.2%),tumor size<4 cm(60.0%), without lymphatic invasion(77.1%),only involvement of the mucous membrane(100%).Statistically significant independent prognostic factors were:TNM staging, diffuse type,metastasis,supraclavicular adenopathy, palpable tumor,and hepatitis or ascites. CONCLUSION:Social determinants are the main risk factors for SC,but not for survival.An advanced clinical stage at consultation is the main cause of poor SC survival.展开更多
In the littlest Higgs model with T-parity(LHT) the mirror quarks induce the special flavor structures and some new flavor-changing couplings,which could greatly enhance the production rates of the flavor-changing proc...In the littlest Higgs model with T-parity(LHT) the mirror quarks induce the special flavor structures and some new flavor-changing couplings,which could greatly enhance the production rates of the flavor-changing processes. We in this paper study some bottom and anti-strange production processes in the LHT model at the International Linear Collider(ILC),i.e.,e^+e^-→bs andγγ→bs.The results show that the production rates of these processes are sizeable for the favorable values of the parameters.Therefore,it is quite possible to test the LHT model or make some constraints on the relevant parameters of the LHT through the detection of these processes at the ILC.展开更多
The Asian summer monsoon(ASM) anticyclone isolates upper-tropospheric air within the interior of the anticyclone from the outside. Forward trajectory simulations in previous studies have shown that much of the air wit...The Asian summer monsoon(ASM) anticyclone isolates upper-tropospheric air within the interior of the anticyclone from the outside. Forward trajectory simulations in previous studies have shown that much of the air within the ASM anticyclone can be trapped for up to two or three weeks, not only laterally but also vertically. Here, we investigate the locations of exit points for upper-tropospheric air trapped within the ASM anticyclone, especially the preferred tropopause-crossing locations, using a 3-dimensional trajectory model. Forward trajectory calculations show two-thirds of the air crosses the tropopause at the southern part of the anticyclone via upward diabatic transport. Furthermore, some air crosses at northern and eastern parts via isentropic shedding, but air crosses rarely through the center of the anticyclone. However, calculations also show that many stratospheric parcels within the anticyclone are traceable from the upper-tropospheric anticyclone. This implies they cannot break through the tropopause directly overhead but instead enter the stratosphere via other entry points.展开更多
文摘AIM:To study the incidence and survival rate of stomach cancer(SC)and its associated factors in a high risk population in Chile. METHODS:The population-based cancer registry of Valdivia,included in the International Agency for Research on Cancer system,covers 356 396 residents of Valdivia Province,Southern Chile.We studied all SC cases entered in this Registry during 1998-2002 (529 cases).Population data came from the Chilean census(2002).Standardized incidence rates per 100 000 inhabitants(SIR)using the world population, cumulative risk of developing cancer before age 75, and rate ratios by sex,age,ethnicity and social factors were estimated.Relative survival(EdererⅡmethod) and age-standardized estimates(Brenner method) were calculated.Specific survival rates(Kaplan-Meier) were measured at 3 and 5 years and survival curves were analyzed with the Logrank and Breslow tests. Survival was studied in relation to demographics, clinical presentation,laboratory results and medical management of the cases.Those variables significantly associated with survival were later included in a Cox multivariate model. RESULTS:Between 1998 and 2002,529 primary gastric cancers occurred in Valdivia(crude incidence rate 29.2 per 100000 inhabitants).Most cases were male(69.0%), residents of urban areas(57.5%)and Hispanic(83.2%), with a low education level(84.5%<8 school years). SC SIR was higher in men than women(40.8 and 14.8 respectively,P<0.001),risk factors were low education RR 4.4(95%CI:2.9-6.8)and 1.6,(95%CI:1.1-2.1) for women and men respectively and Mapuche ethnicity only significant for women(RR 2.2,95%CI:1.2-3.7).Of all cases,76.4%were histologically confirmed,11.5% had a death certificate only(DCO),56.1%were TNM stageⅣ;445 cases(84.1%)were eligible for survival analysis,all completed five years follow-up;42 remained alive,392 died of SC and 11 died from other causes. Specific 5-year survival,excluding cases with DCO,was 10.6%(95%CI:7.7-13.5);5-year relative survival rate was 12.3%(95%CI:9.1-16.1),men 10.9%(95%CI: 7.4-15.2)and women 16.1%(95%CI:9.5-24.5).Fiveyear specific survival was higher for patients aged<55 years(17.3%),with intestinal type of cancer(14.6%), without metastasis(22.2%),tumor size<4 cm(60.0%), without lymphatic invasion(77.1%),only involvement of the mucous membrane(100%).Statistically significant independent prognostic factors were:TNM staging, diffuse type,metastasis,supraclavicular adenopathy, palpable tumor,and hepatitis or ascites. CONCLUSION:Social determinants are the main risk factors for SC,but not for survival.An advanced clinical stage at consultation is the main cause of poor SC survival.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10775039,11075045by Specialized Research Fund for the Doctoral Program of Higher Education under Grant Nos.20094104110001,20104104110001by the Programme for Youth's Talents of Xinyang Normal University under Grant No.200950
文摘In the littlest Higgs model with T-parity(LHT) the mirror quarks induce the special flavor structures and some new flavor-changing couplings,which could greatly enhance the production rates of the flavor-changing processes. We in this paper study some bottom and anti-strange production processes in the LHT model at the International Linear Collider(ILC),i.e.,e^+e^-→bs andγγ→bs.The results show that the production rates of these processes are sizeable for the favorable values of the parameters.Therefore,it is quite possible to test the LHT model or make some constraints on the relevant parameters of the LHT through the detection of these processes at the ILC.
基金supported by the National Natural Science Foundation of China (Grant Nos. 91337214 & 41675040)
文摘The Asian summer monsoon(ASM) anticyclone isolates upper-tropospheric air within the interior of the anticyclone from the outside. Forward trajectory simulations in previous studies have shown that much of the air within the ASM anticyclone can be trapped for up to two or three weeks, not only laterally but also vertically. Here, we investigate the locations of exit points for upper-tropospheric air trapped within the ASM anticyclone, especially the preferred tropopause-crossing locations, using a 3-dimensional trajectory model. Forward trajectory calculations show two-thirds of the air crosses the tropopause at the southern part of the anticyclone via upward diabatic transport. Furthermore, some air crosses at northern and eastern parts via isentropic shedding, but air crosses rarely through the center of the anticyclone. However, calculations also show that many stratospheric parcels within the anticyclone are traceable from the upper-tropospheric anticyclone. This implies they cannot break through the tropopause directly overhead but instead enter the stratosphere via other entry points.
