| PI | first meiotic prophase; isoelectric point; pacing impulse; package insert; pancreatic insufficiency;... |
|---|---|
| PNI | peripheral nerve injury; postnatal infection; prognostic nutritional index |
| PTI | pancreatic trypsin inhibitor; persistent tolerant infection; Pictorial Test of Intelligence; placent... |
| RRI | recurrent respiratory infection; reflex relaxation index; relative response index |
| RRIS | recurrent respiratory infection syndrome |