assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:4436  oio:id           DOID:4436  xsd:string  
1          0           graph  DOID:7986  rdfs:subClassOf  DOID:4436  _IRI        
1          0           graph  DOID:8057  rdfs:subClassOf  DOID:4436  _IRI