Animals animal experiment male nonhuman 243 priority journal controlled study 216 Male 213 article 189 animal tissue 136 mouse 109 Mice 108 animal model 95 animal cell 89 female 89 animal 81 Female 73 rat 64 protein expression 62 Rats 58 Article 56 metabolism 55 physiology 43 unclassified drug 35 Rats, Sprague-Dawley 33 drug effect 33 Humans 31 in vivo study 31 gene expression 30 messenger RNA 30 adult 29