| Si | the most anterior point on the lower contour of the sella turcica [point]; silicon |
|---|---|
| SM | Master of Science; sadomasochism; self-monitoring; silicon microphysiometer; simple mastectomy; skim... |
| CO2 | Carbon Dioxide; 이산화탄소; 지구온난화 |
| PaCO2 | Carbon Dioxide Pressure; amount of CO2 in arterial Blood |
| AaPCO2, (A-a)PCO2 | alveolo-arterial carbon dioxide tension difference |