PMC:7796344 / 98-144
Annnotations
LitCovid-sentences
{"project":"LitCovid-sentences","denotations":[{"id":"T3","span":{"begin":6,"end":17},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"tract\nBackground: Annually, approximately 10 m"}