| PRAS | pre-reduced anaerobically sterilized [medium]; pseudo-renal artery syndrome |
|---|---|
| RAM | random-access memory; rapid alternating movements; rectus abdominis muscle; rectus abdominis myocuta... |
| RAM-FAST | reduced acquisition matrix-Fourier acquired steady state |
| RISC | reduced-instruction-set computer |
| RUA | reduced under anesthesia |