undetermined nitrogenmedical dictionary

The nitrogen of blood, urine, etc., other than urea, uric acid, amino acids, etc., that can be directly estimated; in blood it amounts to about 25 mg per 100 ml.

Urea nitrogen, the portion of nitrogen in a biological sample, such as blood or urine, that derives from its content of urea.

See: blood urea nitrogen.

(05 Mar 2000)