PubMed:32052466 / 223-230
Annnotations
LitCovid-PAS-Enju
{"project":"LitCovid-PAS-Enju","denotations":[{"id":"EnjuParser_T35","span":{"begin":0,"end":7},"obj":"NN"}],"text":"absence"}
LitCovid-TimeML
{"project":"LitCovid-TimeML","denotations":[{"id":"tok41","span":{"begin":0,"end":7},"obj":"NN"}],"text":"absence"}