title: Artifactual reduction in circulating free thyroxine concentration by radioimmunoassay.
mesh_terms: D006493:Heparin / Q000008:administration & dosage / Q000494:pharmacology; D006801:Humans; D007037:Hypothyroidism / Q000097:blood; D007275:Injections, Intravenous; D011863:Radioimmunoassay / Q000379:methods; D013974:Thyroxine / Q000097:blood*
chemical_list: D006493:Heparin; D013974:Thyroxine