PMC:7795856 / 23329-23353 JSONTXT

{"project":"LitCovid-sentences","denotations":[{"id":"T131","span":{"begin":0,"end":2},"obj":"Sentence"},{"id":"T132","span":{"begin":3,"end":24},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"4. Materials and Methods"}