| NOEL | no observed effect level |
|---|---|
| PDL | pancreatic duct ligation; periodontal ligament; poorly differentiated lymphocyte; population doublin... |
| PLM | percent labeled mitoses; periodic leg movement; plasma level monitoring; polarized light microscopy |
| PSIL | preferred frequency speech interference level |
| PTL | peritoneal telencephalic leukoencephalomyopathy; pharyngotracheal lumen; plasma thyroxine level post... |