1. From University of British Columbia, Vancouver, British Columbia, Canada; McMaster University, Hamilton, Queen's University, Kingston, Hotel-Dieu Grace Hospital, Windsor, University of Toronto, Toronto, and Sudbury Regional Hospital, Sudbury, Ontario, Canada; University of Alberta Hospital, Edmonton, Alberta, Canada; Dalhousie University, Halifax, Nova Scotia, Canada; and Hopital Henri Mondor, Universite Paris-Val de Marne, Creteil, France.