PubMed:32031570 / 1947-1954
Annnotations
LitCovid-PAS-Enju
{"project":"LitCovid-PAS-Enju","denotations":[{"id":"EnjuParser_T353","span":{"begin":0,"end":7},"obj":"NN"}],"text":"opacity"}
LitCovid-TimeML
{"project":"LitCovid-TimeML","denotations":[{"id":"tok413","span":{"begin":0,"end":7},"obj":"NN"}],"text":"opacity"}