| SPBI | serum protein-bound iodine |
|---|---|
| SPI | Self-Perception Inventory; serum precipitable iodine; serum protein index; Shipley Personal Inventor... |
| THUG | thyroid uptake gradient |
| T3RU | triiodothyronine resin uptake |
| TU | thiouracil; thyroid uptake; Todd unit; toxin unit; transmission unit; transurethral; tuberculin unit... |