1. Endocrine Unit (R.C.G., Y.G., M.B., H.J.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
2. Department of Biological Sciences (B.P., M.R.P., D.A.R.), Illinois State University, Normal, Illinois 61790
3. Department of Oral and Developmental Biology (B.L.), Harvard School of Dental Medicine, The Forsyth Institute, Boston, Massachusetts 02115