Molecular bases of pseudo-homozygous APC resistance: the compound heterozygosity for FV R506Q and a FV null mutation results in the exclusive presence of FV Leiden molecules in plasma - Castoldi, E; Kalafatis, M; Lunghi, B; Simioni, P; Loannou, P; Petio, M; Girolami, A; Mann, K; Bernardi, F (Thromb Haemost, 1998)