assertion  retraction  graph  subject     predicate        object     datatype    annotation
1          0           graph  DOID:11819  rdfs:subClassOf  DOID:1426  _IRI        
1          0           graph  DOID:1426   oio:id           DOID:1426  xsd:string  
1          0           graph  DOID:11885  rdfs:subClassOf  DOID:1426  _IRI