Authors: Y Yamaoka; M S Osato; A R Sepulveda; O Gutierrez; N Figura; J G Kim; T Kodama; K Kashima; D Y Graham Journal: Epidemiol Infect Date: 2000-02 Impact factor: 2.451
Authors: Y Yamaoka; H M El-Zimaity; O Gutierrez; N Figura; J G Kim; T Kodama; K Kashima; D Y Graham; J K Kim Journal: Gastroenterology Date: 1999-08 Impact factor: 22.682