assertion  retraction  graph  subject     predicate        object   datatype    annotation
1          0           graph  DOID:60009  rdfs:subClassOf  DOID:53  _IRI        
1          0           graph  DOID:1785   rdfs:subClassOf  DOID:53  _IRI        
1          0           graph  DOID:53     oio:id           DOID:53  xsd:string