PMC:7102662 / 45-66
Annnotations
LitCovid-sentences
{"project":"LitCovid-sentences","denotations":[{"id":"T3","span":{"begin":1,"end":20},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"\nBackground and aims\n"}