RT Journal Article SR Electronic T1 Fistulising Crohn’s disease: MMPs gone awry JF Gut JO Gut FD BMJ Publishing Group Ltd and British Society of Gastroenterology SP 622 OP 624 DO 10.1136/gut.2003.034207 VO 53 IS 5 A1 D Schuppan A1 T Freitag YR 2004 UL http://gut.bmj.com/content/53/5/622.abstract AB