[1] Mayo Clin, Dept Gastroenterol & Hepatol, Coll Med, Rochester, MN 55905 USA
[2] Calif Pacific Med Ctr, San Francisco, CA USA
[3] Univ Florida, Sect Hepatobiliary Dis, Gainesville, FL USA
[4] Univ Calif San Francisco, San Francisco, CA 94143 USA
[5] Univ Colorado, Denver, CO 80202 USA
[6] Roche, Nutley, NJ USA
[7] Genentech Inc, San Francisco, CA 94080 USA