A compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids.
Blood Urea Nitrogen
The urea concentration of the blood stated in terms of nitrogen content. Serum (plasma) urea nitrogen is approximately 12% higher than blood urea nitrogen concentration because of the greater protein content of red blood cells. Increases in blood or serum urea nitrogen are referred to as azotemia and may have prerenal, renal, or postrenal causes. (From Saunders Dictionary & Encyclopedia of Laboratory Medicine and Technology, 1984)
A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.
An enzyme that catalyzes the conversion of urea and water to carbon dioxide and ammonia. EC 220.127.116.11.
An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.
Urea Cycle Disorders, Inborn
Rare congenital metabolism disorders of the urea cycle. The disorders are due to mutations that result in complete (neonatal onset) or partial (childhood or adult onset) inactivity of an enzyme, involved in the urea cycle. Neonatal onset results in clinical features that include irritability, vomiting, lethargy, seizures, NEONATAL HYPOTONIA; RESPIRATORY ALKALOSIS; HYPERAMMONEMIA; coma, and death. Survivors of the neonatal onset and childhood/adult onset disorders share common risks for ENCEPHALOPATHIES, METABOLIC, INBORN; and RESPIRATORY ALKALOSIS due to HYPERAMMONEMIA.
Kidney Concentrating Ability
The ability of the kidney to excrete in the urine high concentrations of solutes from the blood plasma.
The internal portion of the kidney, consisting of striated conical masses, the renal pyramids, whose bases are adjacent to the cortex and whose apices form prominent papillae projecting into the lumen of the minor calyces.
Membrane Transport Proteins
Proteins obtained from foods. They are the main source of the ESSENTIAL AMINO ACIDS.
Spectrum Analysis, Raman
A clear, colorless liquid rapidly absorbed from the gastrointestinal tract and distributed throughout the body. It has bactericidal activity and is used often as a topical disinfectant. It is widely used as a solvent and preservative in pharmaceutical preparations as well as serving as the primary ingredient in ALCOHOLIC BEVERAGES.
A homologous group of cyclic GLUCANS consisting of alpha-1,4 bound glucose units obtained by the action of cyclodextrin glucanotransferase on starch or similar substrates. The enzyme is produced by certain species of Bacillus. Cyclodextrins form inclusion complexes with a wide variety of substances.