1. University Department of Surgery and Liver Transplant Unit, Royal Free Hospital, Royal Free and University College Medical School, Pond Street, London NW3 2QG, U.K.
2. University Department of Histopathology, Royal Free Hospital, Royal Free and University College Medical School, Pond Street, London NW3 2QG, U.K.
3. Biophysics Unit, Institute of Child Health, University College London Medical School, London WC1N 1EH, U.K.