assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:3850  oio:id           DOID:3850  xsd:string  
1          0           graph  DOID:2431  rdfs:subClassOf  DOID:3850  _IRI        
1          0           graph  DOID:264   rdfs:subClassOf  DOID:3850  _IRI