assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:6997  rdfs:subClassOf  DOID:6992  _IRI        
1          0           graph  DOID:6996  rdfs:subClassOf  DOID:6992  _IRI        
1          0           graph  DOID:6993  rdfs:subClassOf  DOID:6992  _IRI        
1          0           graph  DOID:6992  oio:id           DOID:6992  xsd:string