assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:5526  rdfs:subClassOf  DOID:4893  _IRI        
1          0           graph  DOID:4893  oio:id           DOID:4893  xsd:string  
1          0           graph  DOID:4892  rdfs:subClassOf  DOID:4893  _IRI