There are multiple definitions:

1. tracer-to-tracee ratio(English)

   • the conventional kinetic formalism used for radioactive data can be applied to estimate noncompartmental parameters using stable isotope tracer data
   • OGTT
   • Medical Physics, Model(ing), Ratio-based metric
   • https://journal…1992.262.6.E968

2. time to recurrence(English)

   • ATAC, CLBC, DFS
   • Quality and outcomes, Oncology
   • https://doi.org…1002/cncr.11745

3. time in therapeutic range(English)

   • NVAF, NOAC, VKA, AF, LCHAD, CHA2DS2-VASc
   • Therapeutic approaches, Guidelines
   • https://doi.org…390/jcm10132866
   • https://doi.org…3/ageing/afq059
   • https://www.mdc…ion-stroke-risk

4. timing transition region(English)

   • regions that have a gradient of replication timing from their early-replicating sides to their late-replicating sides
   • LAD, TAD
   • Genomics
   • https://www.ncb…les/PMC3721284/

5. transthyretin(English)

   • related amyloidoses encompass two forms of disease: familial type arising from misfolding of a mutated or variant protein (familial amyloid cardiomyopathy or familial amyloidotic polyneuropathy [FAP]) and a sporadic, nongenetic disease caused by misaggregation of wild-type transthyretin (senile systemic amyloidosis (SSA). Cardiac amyloidosis can also be caused by other precursor proteins such as apolipoprotein A1, but the prevalence of disease is low
   • FAP, SSA, ATTR, hATTR
   • Cardiology, Neuropathy
   • https://doi.org…NAHA.111.078915
   • https://doi.org…47/TCRM.S219979

6. total time by the rater(English)

   • TTFP, TT
   • Physiology, Musculoskeletal system
   • https://doi.org…hys.2022.874632