| OLS | oubain-like substance |
|---|---|
| PGS | peristent gross splenomegaly; Pettigrew syndrome; plant growth substance; postsurgical gastroparesis... |
| PLS | Papillon-Lefevre syndrome; polydactyly-luxation syndrome; preleukemic syndrome; primary lateral scle... |
| RCS | rabbit aorta-contracting substance; red cell suspension; reticulum cell sarcoma; right coronary sinu... |
| RDS | Raskin Depression Scale; respiratory distress syndrome; reticuloendothelial depressing substance; rh... |