[1] Nagasaki Chuo Natl Hosp, WHO, Collaborat Ctr Ref & Res Viral Hepatitis, Inst Clin Res, Nagasaki 8560835, Japan
[2] Nagasaki Univ, Sch Med, WHO, Collaborat Ctr Ref & Res Viral Hepatitis, Nagasaki, Japan
[3] Nagasaki Univ, Sch Med, Dept Internal Med 1, Nagasaki, Japan