animal experiment nonhuman 52 controlled study 49 priority journal 44 animal tissue 41 article 38 Animals 37 nitric oxide synthase 36 animal model 33 mouse 30 enzyme activity 29 Nitric Oxide Synthase 27 nitric oxide 27 protein expression 26 female 25 Mice 22 Female 20 rat 20 male 19 animal cell 17 Male 15 signal transduction 15 Nitric oxide synthase 14 inducible nitric oxide synthase 14 Mice, Inbred BALB C 12 enzyme activation 12 Western blotting 11 submandibular gland 11 unclassified drug 11 Enzyme Inhibitors 10