
PubMed:32052373 / 1414-1424
Annnotations
LitCovid-PAS-Enju
{"project":"LitCovid-PAS-Enju","denotations":[{"id":"EnjuParser_T198","span":{"begin":0,"end":10},"obj":"NNS"}],"text":"challenges"}
LitCovid-TimeML
{"project":"LitCovid-TimeML","denotations":[{"id":"tok222","span":{"begin":0,"end":10},"obj":"NNS"}],"text":"challenges"}