About: http://webisa.webdatacommons.org/288940037

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Urea is a nitrogen-based waste product secreted by the kidneys. ... along with ammonia, urea is therefore classified as non-protein nitrogen (NPN) ...
http://www.w3.org/ns/prov#wasQuotedFrom	bio-medicine.org