Tabie 21 Kinetic Analysis of '**{ Studies Location and year Marshalls. March 1965 Subject No, Exposed* Unexposed* BNL, June 1965 Marshalls, March 1966 2 pre TSH per day L.10 (0.34-2.57) 0.81 (O.17-1.99) per day 0.67 (0.33-1.27) 0.79 Thyroid fraction‘ Iodide space, liters 0.40 (0.250.635 ) 0.52 (0.23+1.47) (0.26-0.77) 0.80 Lig 1.71 0.41 20 pre TSH post TSH 2.12 1.10 2.30 1.81 0.49 0.62 64 pre TSH post TSH 1.88 0.81 1.08 1.56 0.36 0.66 3 0.52 0.005 0.01 5 0.86 0.14 0.14 1.13 0.15 0.42 2 (partial thyroidectomy) 1.20 Thyroid,° post TSH 69 (partial thyroidectomy) BNL, June 1966 Urine,’ 0.60 33.3 1.53 0.92 0.37 20.0 61 (on thyroxine) 1.26 0.58 0.31 29.0 54 0.50 0.69 0.58 65 1.08 0.72 0.40 20.4 59 (on thyroxine) 1.65 0.10 0.06 16.9 42 pre TSH post TSH 1.87 0.69 1.29 1.30 0.41 0.65 61 pre TSH post TSH 0.13 0.50 0.48 1.67 0.78 0.77 33 pre TSH post TSH 0.20 0.45 0.97 1.57 0.82 0.78 65 pre TSH post TSH 1.83 2.35 0.82 1.14 0.31 0.33 39 pre TSH post TSH 3.53 1.29 1.51 3.09 0.30 0.71 *Fraction of extrathyroidal iodide excreted in the urine per day (A,,). "Fraction of extrathyroidal iodide transferred to the thyroid per day (A,,). *Theoretical thyroid uptake, A.,/(Ao.+As1)“Mean and range of 12 subjects. *Mean and range of 9 subjects. signs of hypothyroidism: coarse facial features, dry skin, and Achilles’ reflexes with typical sluggish return. There was no palpable thyroid tissue. They did not show apparent mentalretardation. TSH levels (Table 20) were markedly elevated in both boys, corroborating the presence of primary hypo- thyroidism. Figure 28 shows bone age retardation in one of these boys. Typical bone dysgenesis associated with hypothyroidism‘? was noted in 1965 in these boys. Figure 29 shows such changesin the heads of the humeri in one case (No. 5). From Table 20 indications can be seen that several other children with thyroid abnormalities (subject Nos. 2, 20, 33, and 65), some of whom