assertion  retraction  graph  subject       predicate        object      datatype    annotation
1          0           graph  DOID:0050926  rdfs:subClassOf  DOID:13499  _IRI        
1          0           graph  DOID:3216     rdfs:subClassOf  DOID:13499  _IRI        
1          0           graph  DOID:13499    oio:id           DOID:13499  xsd:string