PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 2158511-4 1990 Ba2+ and Sr2+ could not alone promote cytolysin-mediated cytolysis but did enhance Ca2(+)-driven cytolysis. strontium cation 9-13 perforin 1 Homo sapiens 38-47