Measurements of free thyroxine: comparison of per cent of free thyroxine in diluted and undiluted sera.
The effect of dilution on values of the per cent of free T4 in serum (%FT4) measured by equilibrium dialysis, was determined by comparing the values for %FT4 in diluted and undiluted specimens. The specimens studied were sera obtained from 10 normal subjects, 10 patients with hyperthyroidism, 5 with hypothyroidism, and 9 women with normal pregnancy. The method of analysis employed was that described by Sterling and Brenner, except that the 125I-thyroxine used was predialyzed to remove non-thyroxine contaminants and that "corrected" values for %FT4 were calculated by dividing measured values by the numerical extent to which the serum had been diluted.
D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000097:blood; D011247:Pregnancy; D013849:Thimerosal / Q000494:pharmacology; D013960:Thyroid Function Tests; D013974:Thyroxine / Q000097:blood*
D013849:Thimerosal; D013974:Thyroxine