| PAST | periodic acid-Schiff technique |
|---|---|
| PA-T-SP | periodic acid-thiocarbo-hydrazide-silver proteinate |
| PB | British pharmacopeia [Pharmacopoeia Britannica]; paraffin bath; Paul-Bunnell [antibody]; periodic br... |
| per | perineal; periodicity, periodic |
| PHE | periodic health examination; phenylephrine |