PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 6773982-11 1980 In subtype IIB, binding of factor VIII/von Willebrand factor to platelets occurred at lower concentrations of ristocetin than required for normal and multimers of smaller size than in normal bound. Ristocetin 110-120 von Willebrand factor Homo sapiens 39-60