There are multiple definitions:

1. parallel elastic element(English)

   • PEC, SEE
   • Biophysics

2. petroleum ether extract(English)

   • γ-GTP, ANIT, ALP, ALT, AST, DBIL, TBA, Tbil, SD
   • Liver disease, Experimental animal
   • https://doi.org…jep.2015.06.043

3. propolis ethanolic extract(English)

   • WKBE
   • Nutrition, Adiposity
   • https://doi.org…3390/nu16020310

4. primary effectiveness endpoint(English)

   • AAD, AE, AF, AFEQT, AFL, AT, BMI, CHA2DS2-VASc, CTI, DCCV, EAM, PAE, PAF, PFA, PV, PVI
   • Statistics
   • https://doi.org…NAHA.124.070333