assertion  retraction  graph  subject     predicate        object     datatype    annotation
1          0           graph  DOID:1927   oio:id           DOID:1927  xsd:string  
1          0           graph  DOID:1926   rdfs:subClassOf  DOID:1927  _IRI        
1          0           graph  DOID:14499  rdfs:subClassOf  DOID:1927  _IRI