PubMed:32094589 / 917-924
Annnotations
LitCovid-PAS-Enju
{"project":"LitCovid-PAS-Enju","denotations":[{"id":"EnjuParser_T142","span":{"begin":0,"end":7},"obj":"NN"}],"text":"barrier"}
LitCovid-TimeML
{"project":"LitCovid-TimeML","denotations":[{"id":"tok151","span":{"begin":0,"end":7},"obj":"NN"}],"text":"barrier"}