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Urea - is an organic compound with the chemical formula CO(NH2)2. The molecule has two -NH2 groups joined by a carbonyl (C=O) functional group.
U 1304 (OTTO) Urea ACS reagent, 99.0-100.5% Cas 57-13-6 - used to adjust the urea nitrogen concentration to a preferred range in blood reservoir for evaluating the dialyzer urea clearance.