PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 11430769-8 2001 The dogma that an oral dose of the unnatural C-6 isomer of 5-formyltetrahydrofolate is not bioactive in human subjects does not withstand scrutiny, most probably due to the previously unrecognized in vivo oxidation of 10-formyltetrahydrofolate. Leucovorin 59-83 complement C6 Homo sapiens 45-48