| PrA-HPA | protein A hemolytic plaque assay |
|---|---|
| REA | radiation emergency area; radioenzymatic assay; renal anastomosis; right ear advantage |
| RIBA | recombinant immunoblot assay |
| RIPA | radioimmunoprecipitation assay |
| RISA | radioactive iodinated serum albumin; radioimmunosorbent assay |