Association of Lewis and Secretor gene polymorphisms and Helicobacter pylori seropositivity among Japanese-Brazilians - Oba-Shinjo, Sueli Mieko; Uno, Miyuki; Ito, Lucy Sayuri; Shinjo, Samuel Katsuyuki; Marie, Suely Kazue Nagahashi; Hamajima, Nobuyuki (Journal of gastroenterology, 2004)