TY - JOUR T1 - Reply JF - Gut JO - Gut SP - 561 LP - 561 DO - 10.1136/gut.40.4.561-b VL - 40 IS - 4 AU - R J Farrell AU - P W N Keeling Y1 - 1997/04/01 UR - http://gut.bmj.com/content/40/4/561.3.abstract N2 - 300 Multiple ChoicesThis is a pdf-only article and there is no markup to show you.full-text.pdf ER -