[1] Natl Ctr Replacement Refinement & Reduct Anim Res, London, England
[2] Univ Bristol, Sch Vet Sci, Bristol BS18 7DU, Avon, England
[3] Univ Bristol, Sch Biol Sci, Bristol, Avon, England
[4] Univ London Imperial Coll Sci Technol & Med, Natl Heart & Lung Inst, London SW7 2AZ, England
[5] Univ Oxford, Ctr Stat Med, Oxford, England