1. From the Cardiovascular Section (D.R.P., J.K.A., L.X., T.M., J.O.-K., R.B., J.W., D.A.S., W.S.C., D.B.S.), Department of Medicine, Boston University Medical Center; The Myocardial Biology Unit (D.R.P., J.K.A., L.X., T.M., R.B., J.W., D.A.S., W.S.C., D.B.S.), Boston University School of Medicine; the Department of Biophysics (J.V.), Boston University Medical Center; and the Boston Veterans Administration Medical Center (K.S.), Boston, Mass. Current affiliation for P.P. is Henry Ford Hospital, Detroit...