AIM:To clarify the similarities and differences in gastric cancer epidemiology between Japan and China.METHODS:A comprehensive literature search of the PubMed database was performed.The relevant literature published i...AIM:To clarify the similarities and differences in gastric cancer epidemiology between Japan and China.METHODS:A comprehensive literature search of the PubMed database was performed.The relevant literature published in China was also been cited.Data on incidence and mortality rates in 2008 were obtained from the Cancer Mondial database,published by International Agency for Research on Cancer at http://www-dep.iarc.fr/.RESULTS:Gastric cancer remains a significant publichealth burden in both Japan and China.The prevalence of Helicobacter pylori(H.pylori)colonization is high in the adult populations of both countries.Accumulating evidence from intervention studies in both countries has shown the effectiveness of H.pylori eradication in reduc-ing gastric cancer incidence.There are differences,however,in many aspects of gastric cancer,including patterns of incidence and mortality,trends in the prevalence of H.pylori infection,H.pylori strains,the magnitude of risk of gastric cancer related to H.pylori infection,and associations with dietary habits.Compared with China,Japan has seen a more rapid decline in H.pylori infection among adolescents.While Japanese cohort studies have dominated the literature concerning the associations between gastric cancer and dietary habits,numerous case-control studies in China suggest a positive association between a high intake of preserved fish and vegetables and gastric cancer risk.There is a need for a multidisciplinary research approach to understand the interactions between various strains of H.pylori,host factors,and other lifestyle and environmental factors in gastric carcinogenesis in both countries.CONCLUSION:The shared high incidence of gastric cancer and high prevalence of H.pylori,as well as differences in many aspects of gastric cancer,provide an excellent opportunity to establish Sino-Japanese collaborations.展开更多
For some time, two major kinds of Total Factor Productivity （TFP） have existed independently of each other： the Solow residual and the Malmquist Productivity Index （MPI）. The Solow residual was introduced in macr...For some time, two major kinds of Total Factor Productivity （TFP） have existed independently of each other： the Solow residual and the Malmquist Productivity Index （MPI）. The Solow residual was introduced in macro economic growth models, and the MPI has been used in micro economics and management studies. As both indices were developed independently, few studies utilize both together and compare the results. This paper uses the same data to compare the two productivity indices by setting to determine the economic implications of combining the two indices. We discovered that we could decompose TFP with each aspect of the Soiow residual and MPI. We could then interpret their relationship in the business cycle. Our results indicated that the frontier shift in MPI of Japanese firms often occurred when the Solow residual increased, meaning that improving oroductivitv with the Solow residual could be generated by a firm that could shift new production frontiers.展开更多
A dynamic model of schistosoma japonicum transmission is presented that incorporates effects of the prepatent periods of the different stages of schistosoma into Baxbour＇s model. The model consists of four delay diff...A dynamic model of schistosoma japonicum transmission is presented that incorporates effects of the prepatent periods of the different stages of schistosoma into Baxbour＇s model. The model consists of four delay differential equations. Stability of the disease free equilibrium and the existence of an endemic equilibrium for this model are stated in terms of a key threshold parameter. The study of dynamics for the model shows that the endemic equilibrium is globally stable in an open region if it exists and there is no delays, and for some nonzero delays the endemic equilibrium undergoes Hopf bifurcation and a periodic orbit emerges. Some numerical results are provided to support the theoretic results in this paper. These results suggest that prepatent periods in infection affect the prevalence of schistosomiasis, and it is an effective strategy on schistosomiasis control to lengthen in prepatent period on infected definitive hosts by drug treatment （or lengthen in prepatent period on infected intermediate snails by lower water temperature）.展开更多
基金Supported by Grant-in-Aid from the Third Term Comprehensive Control Research for Cancer,the Ministry of Health,La-bour and Welfare,Japan
文摘AIM:To clarify the similarities and differences in gastric cancer epidemiology between Japan and China.METHODS:A comprehensive literature search of the PubMed database was performed.The relevant literature published in China was also been cited.Data on incidence and mortality rates in 2008 were obtained from the Cancer Mondial database,published by International Agency for Research on Cancer at http://www-dep.iarc.fr/.RESULTS:Gastric cancer remains a significant publichealth burden in both Japan and China.The prevalence of Helicobacter pylori(H.pylori)colonization is high in the adult populations of both countries.Accumulating evidence from intervention studies in both countries has shown the effectiveness of H.pylori eradication in reduc-ing gastric cancer incidence.There are differences,however,in many aspects of gastric cancer,including patterns of incidence and mortality,trends in the prevalence of H.pylori infection,H.pylori strains,the magnitude of risk of gastric cancer related to H.pylori infection,and associations with dietary habits.Compared with China,Japan has seen a more rapid decline in H.pylori infection among adolescents.While Japanese cohort studies have dominated the literature concerning the associations between gastric cancer and dietary habits,numerous case-control studies in China suggest a positive association between a high intake of preserved fish and vegetables and gastric cancer risk.There is a need for a multidisciplinary research approach to understand the interactions between various strains of H.pylori,host factors,and other lifestyle and environmental factors in gastric carcinogenesis in both countries.CONCLUSION:The shared high incidence of gastric cancer and high prevalence of H.pylori,as well as differences in many aspects of gastric cancer,provide an excellent opportunity to establish Sino-Japanese collaborations.
文摘For some time, two major kinds of Total Factor Productivity （TFP） have existed independently of each other： the Solow residual and the Malmquist Productivity Index （MPI）. The Solow residual was introduced in macro economic growth models, and the MPI has been used in micro economics and management studies. As both indices were developed independently, few studies utilize both together and compare the results. This paper uses the same data to compare the two productivity indices by setting to determine the economic implications of combining the two indices. We discovered that we could decompose TFP with each aspect of the Soiow residual and MPI. We could then interpret their relationship in the business cycle. Our results indicated that the frontier shift in MPI of Japanese firms often occurred when the Solow residual increased, meaning that improving oroductivitv with the Solow residual could be generated by a firm that could shift new production frontiers.
基金supported by the National Natural Science Foundation of China(Nos.10831003,10925102)the Program of Shanghai Subject Chief Scientist(No.10XD1406200)
文摘A dynamic model of schistosoma japonicum transmission is presented that incorporates effects of the prepatent periods of the different stages of schistosoma into Baxbour＇s model. The model consists of four delay differential equations. Stability of the disease free equilibrium and the existence of an endemic equilibrium for this model are stated in terms of a key threshold parameter. The study of dynamics for the model shows that the endemic equilibrium is globally stable in an open region if it exists and there is no delays, and for some nonzero delays the endemic equilibrium undergoes Hopf bifurcation and a periodic orbit emerges. Some numerical results are provided to support the theoretic results in this paper. These results suggest that prepatent periods in infection affect the prevalence of schistosomiasis, and it is an effective strategy on schistosomiasis control to lengthen in prepatent period on infected definitive hosts by drug treatment （or lengthen in prepatent period on infected intermediate snails by lower water temperature）.
