controlled study real time polymerase chain reaction 104 nonhuman 96 article 68 priority journal 64 Animals 56 human 54 Article 52 Real-Time Polymerase Chain Reaction 52 protein expression 50 animal experiment 46 Humans 44 unclassified drug 44 Female 42 animal cell 42 animal tissue 42 human cell 42 metabolism 42 mouse 40 female 38 messenger RNA 38 Western blotting 36 Male 34 gene expression 34 male 34 genetics 32 Mice 30 animal model 30 signal transduction 30 animal 26