assertion  retraction  graph  subject          predicate        object           datatype    annotation
1          0           graph  obo:CHEBI_47857  rdfs:label       ureas            xsd:string  
1          0           graph  obo:CHEBI_47857  oio:id           CHEBI:47857      xsd:string  
1          0           graph  obo:CHEBI_47857  rdfs:subClassOf  obo:CHEBI_33256  _IRI        
1          0           graph  obo:CHEBI_47857  rdf:type         owl:Class        _IRI