English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Plasma or serum free thyroxine (T 4 ) was measured by a novel non-isotopic, two-step immunossay in 373 consecutive patients attending a thyroid clinic, in whom thyroid status was categorized according to clinical findings, supported by routine thyroid function tests. The 95% confidence limit of free T 4  in the euthyroid patients ( n = 112) was 7–20 pmol/L. Free T 4  concentrations within the reference range were found in six of 40 patients with primary hypothyroidism and nine of 182 patients with overt thyrotoxicosis, six of whom had T 3  toxicosis. Serum or plasma free T 4  measured by the two-step method showed improved diagnostic specificity over an analogue RIA in selected groups of euthyroid patients in whom abnormal binding of analogue T 4  can affect the validity of the result. Free T 4  results found by analogue RIA and the two-step method in 58 patients who were receiving thyroxine replacement therapy were similar. The between-assay precision of the two-step method was poor ranging from a coefficient of variation of 9·7% to 19·3% over a free T 4  concentration range of 5·0 to 46·0 pmol/L. We conclude that the two-step methodology offers diagnostic advantages for a laboratory which receives specimens from such patients for exclusion of thyroid disease but that improved assay precision is required before it could be used in a routine situation.

Non-Isotopic, Two-Step Free Thyroxine Immunoassay: A Better Measure of Free Thyroxine than Analogue Radioimmunoassay