EVALUATION OF FREE THYROXIN TECHNIQUES

最近，用于测量血清的非同位素（通常是自动化的）免疫测定法， 游离甲状腺素（FT4）已成为可用。 虽然代价更高 放射免疫测定，它们是相当方便。 我们研究了 内源性白蛋白和甲状腺素结合球蛋白影响 五种自动化非同位素方法测量FT4浓度 （ES300上的Enzymun [一步]，Stratus I和II [一步半]， 两个人，两个人。 我们观察到，（a） 受内源性血清结合蛋白的影响很小，（B）sccm 具有足够的运行内精密度，以证明进行单次 对患者标本进行测量。 目前正在进行更多的研究 评估FT4方法的诊断性能， 放射性标记的T4或T4类似物用于非甲状腺疾病患者。

Recently, nonisotopic (often automated) immunoassays for measuring serum free thyroxin (FT4) have become available. Though more costly then radioimmunoassays, they are considerably more convenient. We studied the influence of endogenous albumin and thyroxin-binding globulin concentration on five automated, nonisotopic methods of measuring FT4 (Enzymun on ES300 [one-step], Stratus I and II [one-and-a-half-step], Delfia [two-step], and IMx [two-step]). We observed that they (a) are influenced very little by endogenous serum binding proteins and (b) seem to have sufficient within-run precision to justify performing single measurements on patient specimens. Additional studies are now in progress to assess the diagnostic performance of FT4 methods based on the use of radiolabeled T4 or T4 analogs in patients with non-thyroidal illnesses.