There are multiple definitions:

1. Klenow fragment(English)

   • a DNA polymerase enzyme that lacks the 5' to 3' exonuclease activity of intact DNA Polymerase I, but does exhibit the 5' to 3' DNA polymerase and 3' to 5' exonuclease activities
   • DNA
   • Biochemistry
   • https://www.ncb…icles/PMC19848/

2. Kalman filter(English)

   • EKF, UKF
   • Filtering (of signals)

3. knee flexion(English)

   • superimposing hip extension on knee flexion evokes higher activation in biceps femoris than knee flexion alone
   • HE-KF, EMG
   • Shoulder and other joints, Musculoskeletal system
   • https://doi.org…kin.2021.102541

4. Kayser-Fleischer(English)

   • these rings are golden or brownish rings secondary to copper depositions in the basement membrane of the corneal endothelium
   • CAD, CVD
   • Ophthalmology, Cardiology
   • https://doi.org…jnl-2022-322081