1. From NMR Research Center, Department of Neurology, Henry Ford Health Sciences Center, Case Western Reserve University, Detroit, Mich (Y.C., E.M.V., K.P.G., A.F.J.); Department of Radiology, The University of Chicago Hospitals, Chicago, Ill (E.M.V.); and University of Kansas Medical Center, Kansas City, Kan (K.M.A.W.).