There are multiple definitions:

1. oxytocin challenge test(English)

   • a form of antenatal fetal monitoring that is being utilized by obstetricians to assess fetal well-being
   • FHR
   • Obstetrics
   • https://doi.org…3390/jcm9010131

2. optical coherence tomography(English)

   • a novel intravascular imaging modality using near-infrared light (1,300 nm)
   • GRIN, OCM, SD, IVI, NIRS, SD-OCT, ALG, BA, CB, IVL, IVUS, NCB, PCI, RA, SB, IVOCT, iOCT, MIOCT, FFR, OFR, RFR, VFR, μQFR
   • Imaging, Optics and vision, Medical imaging, Coronary circulation
   • https://doi.org…IONS.120.009870
   • https://doi.org…IONS.123.013702

3. ornithine carbamoyltransferase(English)

   • enzyme that is located in liver mitochondria and functions as a part of the urea cycle
   • OCD, ODC
   • https://www.uni…/uniprot/P00480

4. optimum cutting temperature(English)

   • widely used embedding medium for tissues for histopathologic analysis
   • ITT, KAP, KO, LAMP1, LD, LRP2, MAT, MS, mTOR, NEFA, PAS, PFA, PTEC, RAS, RUBCN, SAT, SFC, TFEB, UN, UVRAG, VPS, WAT, TUNEL, FFA, OA
   • Histochemistry
   • https://doi.org…3X.2009.01139.x
   • https://doi.org…27.2020.1712107

5. organic cation transporter(English)

   • classified within two SLC superfamilies. Superfamily SLCO (formerly SLC21A) consists of organic anion transporting polypeptides (OATPs), while the organic anion transporters (OATs) and the organic cation transporters (OCTs) are classified in the SLC22A superfamily
   • NPE, SLC, OAT, SLCO, OATP
   • Biophysics, Physiology
   • https://doi.org…81.2011.01724.x

6. oxygen challenge test(English)

   • defined as the degree of transcutaneous partial pressure of oxygen (PtcO2) response to 1.0 FiO2. Predictive of mortality for septic patients after resuscitation
   • PI
   • Oxygen, Diagnostics, Sepsis
   • https://doi.org/10.1186/cc12788