metabolism nonhuman controlled study 220 Animals 216 animal 216 genetics 182 priority journal 182 gene expression regulation 170 mouse 136 animal cell 132 article 128 Article 124 unclassified drug 110 Mice 108 human 108 Humans 98 protein expression 96 animal experiment 92 physiology 82 signal transduction 82 animal tissue 78 messenger RNA 76 down regulation 72 Gene Expression Regulation 66 gene expression 64 upregulation 60 female 56 animal model 54 Female 52 Signal Transduction 52