PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 15952226-0 2005 Quantification of cation-pi interactions in protein-ligand complexes: crystal-structure analysis of Factor Xa bound to a quaternary ammonium ion ligand. quaternary ammonium 121-140 coagulation factor X Homo sapiens 100-109