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(yoo-REE-uh NY-truh-jen)
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| Nitrogen in the blood that comes from urea (a substance formed by the breakdown of protein in the liver). The kidneys filter urea out of the blood and into the urine. A high level of urea nitrogen in the blood may be a sign of a kidney problem. Also called blood urea nitrogen and BUN. |
Previous Definitions: | upper endoscopy, upper GI series, urachus, uracil, urea | Next Definitions: | urea/lactic acid-based cream, ureter, ureteronephrectomy, ureteroscopy, urethra |
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