assertion retraction graph subject predicate object datatype annotation 1 0 graph DOID:6812 IAO:0000115 A pilocytic astrocytoma that occurs during childhood. xsd:string "{""oio:hasDbXref"":[{""datatype"":""xsd:string"",""meta"":""owl:Axiom"",""object"":""url:https://ncit.nci.nih.gov/ncitbrowser/ConceptReport.jsp?dictionary=NCI_Thesaurus&ns=ncit&code=C4048""}]}"