1. Johns Hopkins University School of Medicine, Departments of Surgery (R.A.-H., A.R., D.K.A., D.E.), Johns Hopkins Bayview Medical Center, Baltimore, Maryland 21224-2780
2. Medicine (A.R., D.E.), Johns Hopkins Bayview Medical Center, Baltimore, Maryland 21224-2780
3. University of British Columbia (G.S.M.), Department of Medicine, Vancouver, British Columbia, Canada V5Z 1M9
4. University of Pennsylvania School of Medicine (R.P.S.), Department of Medicine, Philadelphia, Pennsylvania 19104-2646