PubMed:32250385 / 959-961
Annnotations
LitCovid-TimeML
{"project":"LitCovid-TimeML","denotations":[{"id":"tok166","span":{"begin":0,"end":2},"obj":"CD"}],"text":"18"}
LitCovid-PD-CLO
{"project":"LitCovid-PD-CLO","denotations":[{"id":"T5","span":{"begin":0,"end":2},"obj":"http://purl.obolibrary.org/obo/CLO_0050510"}],"text":"18"}