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Subcutaneous T4 3 micrograms/100 g body weight or T3 1.2 micrograms/100 g; serum collected five hours later.\ncross_nutrient: Selenoenzyme D2 activates an iodine-containing hormone for feedback; knockout is a machinery experiment.\nevidence_locator: Results: TSH Suppression Studies and Figure 9; pages 2140–2141.\nevidence_spans: [{\"source_document\": \"artifacts/iodine-metabolism-sources/11731615.txt\", \"locator\": \"Primary article Results, Figures 7 and 9; Methods: Assays for Serum T4, T3 and TSH, page 2146\", \"start_char\": 20490, \"end_char\": 22790}]\n[i-met-11731615] Targeted disruption of the type 2 selenodeiodinase gene (DIO2) results in a phenotype of pituitary resistance to T4. 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