assertion  retraction  graph  subject    predicate        object    datatype    annotation
1          0           graph  DOID:706   oio:id           DOID:706  xsd:string  
1          0           graph  DOID:6536  rdfs:subClassOf  DOID:706  _IRI        
1          0           graph  DOID:8584  rdfs:subClassOf  DOID:706  _IRI