assertion retraction graph subject predicate object datatype annotation 1 0 graph DOID:12969 IAO:0000115 A hematologic cancer located_in the central nervous system. xsd:string "{""dce:type"":[{""datatype"":""_IRI"",""meta"":""owl:Axiom"",""object"":""obo:ECO_0007645""}],""oio:hasDbXref"":[{""datatype"":""xsd:string"",""meta"":""owl:Axiom"",""object"":""url:http://www.springerlink.com/content/gl61tx644217n938/""}]}"