PMC:7156291 / 4408-4429
Annnotations
LitCovid-sentences
{"project":"LitCovid-sentences","denotations":[{"id":"T42","span":{"begin":0,"end":21},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"Materials and methods"}