in four groups of subjects free of thyroid disease , the following determinations were made : serum concentrations of thyroxine ( t4 ) , triiodothyronine ( t3 ) , reverse t3 ( rt3 ) and diiodothyronine ( t2 ) , and calculated indices of free thyroxine ( ft4 ) and free triiodothyronine ( ft3 ) .
C0040128
thyroid disease
C0040165
thyroxine