assertion  retraction  graph  subject     predicate        object     datatype    annotation
1          0           graph  DOID:3952   oio:id           DOID:3952  xsd:string  
1          0           graph  DOID:660    rdfs:subClassOf  DOID:3952  _IRI        
1          0           graph  DOID:10493  rdfs:subClassOf  DOID:3952  _IRI