There are multiple definitions:

1. protein kinase R-like endoplasmic reticulum kinase(English)

   • AAA, ADR, AHR, BA, FXR, GPR41, MAPK, OLFR78, PAG, Phe, PXR, SCFA, TGR5, TMA, TMAO, Trp, Tyr
   • Virology, Cardiology, Microbiome, Metabolism
   • https://doi.org…94.2021.1899674
   • https://doi.org…NAHA.123.067547

2. Publishing Ethics Resource Kit(English)

   • Medical publications, Ethics
   • https://www.els…com/editor/perk