1. From the Medical Clinic B Research Unit (N.F., A.S., G.S.) and Medical Clinic A (E.B.B., M.F.), Department of Medicine, University Hospital, Zürich, and Department of Pediatrics, Division of Clinical Chemistry and Biochemistry, University of Zürich (N.B.), Switzerland; and the Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Wash (R.B.W.).