[1] Evangelismos Med Ctr, Dept Gastroenterol 2, Athens 17561P, Faliro, Greece
[2] Athens Naval Hosp, Dept Gastroenterol, Athens, Greece
[3] Beth Israel Deaconess Med Ctr, Dept Gastroenterol, Boston, MA 02215 USA
[4] Univ Athens, Sch Med, Acad Dept Internal Med 2, GR-11527 Athens, Greece
[5] Athens Naval Hosp, Dept Anesthesiol, Athens, Greece