Affiliation: | (1) School of Medicine, Boston University Medical Center, 80 E. Concord Street, 02118 Boston, Mass.;(2) Dept. of Physiology, Harvard Medical School, Boston, Mass.;(3) Biophysics Program, Brandeis University, Waltham, Mass.;(4) Depts. Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Mass. |