assertion retraction graph subject predicate object datatype annotation 1 0 graph DOID:8043 IAO:0000115 A parachordoma arising from the chest wall. xsd:string "{""oio:hasDbXref"":[{""datatype"":""xsd:string"",""meta"":""owl:Axiom"",""object"":""url:https://pubmed.ncbi.nlm.nih.gov/24135242/""}]}"