| PTV | planning target volume; posterior tibial vein |
|---|---|
| PTV2 | planning target volume 2 |
| STAG | slow-target attaching globulin; split-thickness autogenous graft |
| TAG | target attaching globulin; technical advisory group; thymine, adenine, and guanine |
| TAPA | target of antiproliferative antibody |
| facility regulation and control | Formal voluntary or governmental procedures and standards required of hospitals and health or other facilities to improve operating efficiency, and for the protection of the consumer. (12 Dec 1998) |
|---|---|
| feedback regulation | <physiology> Control mechanism that uses the consequences of a process to regulate the rate at which the process occurs: if, for example: the products of a reaction inhibit the reaction from proceeding (or slow down the rate of the reaction), then there is negative feedback, something that is very common in metabolic pathways. Positive feedback is liable to lead to exponential increase and may be explosively dangerous in some cases. Other examples are the action of voltage dependent sodium channels in generating action potentials and the activation of blood clotting factors V and VIII by thrombin. Without damping, feedback can lead to resonance (hunting) and oscillation in the system. (18 Nov 1997) |
| up-regulation | Opposite of down-regulation. (05 Mar 2000) |
| up-regulation (physiology) | Process that increases ligand/receptor interactions due to an increase in the number of available receptors. (12 Dec 1998) |