assertion  retraction  graph  subject     predicate        object   datatype    annotation
1          0           graph  DOID:1459   rdfs:subClassOf  DOID:50  _IRI        
1          0           graph  DOID:1781   rdfs:subClassOf  DOID:50  _IRI        
1          0           graph  DOID:2891   rdfs:subClassOf  DOID:50  _IRI        
1          0           graph  DOID:12176  rdfs:subClassOf  DOID:50  _IRI        
1          0           graph  DOID:50     oio:id           DOID:50  xsd:string