1. Endocrine Unit, Massachusetts General Hospital, Boston 02114.
2. Department of Medicine, Harvard Medical School, Boston, MA 02114.
3. Department of Pediatrics, Harvard Medical School, Boston, MA 02114.
4. Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139..
5. Veterans Administration-Outpatient Clinic and Tufts University, School of Dental Medicine, Boston, MA 02111.