1. From the Department of Medicine, Boston Medical Center (R.C.L.), the Department of Medicine, Boston University School of Medicine (R.C.L.), the Departments of Medicine (J.N.C., A.A.W.), Radiology (T.T.P.), and Pathology (J.A.B.), Massachusetts General Hospital, and the Departments of Medicine (J.N.C., A.A.W.), Radiology (T.T.P.), and Pathology (J.A.B.), Harvard Medical School — all in Boston.