assertion  retraction  graph  subject             predicate        object                 datatype    annotation
1          0           graph  obo:UBERON_0004923  rdfs:label       organ component layer  xsd:string  
1          0           graph  obo:UBERON_0004923  oio:id           UBERON:0004923         xsd:string  
1          0           graph  obo:UBERON_0004923  rdfs:subClassOf  obo:UBERON_0000064     _IRI        
1          0           graph  obo:UBERON_0004923  rdf:type         owl:Class              _IRI