The process ofageing is to a large extent due to the damagingconsequence of free radical action (lipid peroxidation,DNA damage, protein oxidation) (Harman, 1956).Convincing evidence for the association ofoxidative/ nitrosative stress and acute and chronicdiseases lies on validated biomarkers of oxidativestress.
The radioactive iodine uptake test, or RAIU test, is a type of scan used in the diagnosis of thyroid problems, particularly hyperthyroidism.he normal uptake is between 15 and 25 percent, but this may be forced down if, in the meantime, the patient has eaten foods high in iodine, such as dairy products and seafood. Low uptake suggests thyroiditis, high uptake suggests Graves' disease, and unevenness in uptake suggests the presence of a nodule.
Measurements of serum TSH levels were done twice a day from 08.00 to 09.00 a.m. and from 2.00 to 4.00 p.m. RESULTS: The morning median TSH value in the patients with subclinical hypothyroidism was 5.83 mU/L; in the afternoon, it was 3.79 mU/L. The range of TSH circadian variability reached the level of 73%. According to the current TSH reference interval, hypothyroidism was not diagnosed in about 50% of the cases in the afternoon. The morning median TSH value in the patients taking l-thyroxine was 3.27 mU/L; it decreased to the value of 2.18 mU/L in the afternoon.