1. Thyroid Section (I.M.G., A.L.M.), Endocrine Division, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS-90035-903, Brazil;
2. Laboratory of Endocrine Neurobiology Institute of Experimental Medicine (B.G.), Hungarian Academy of Sciences, Budapest H-1083, Hungary;
3. Thyroid Section (J.W.H., B.Z., P.R.L.), Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts 02115