There are multiple definitions:

1. dithiothreitol(English)

   • a reducing agent
   • Abbreviation may be used in Am. Soc. Physiol. journals without definition.
   • PSS
   • Physiology, Biochemistry

2. diluted thrombin time(English)

   • measures only the TT in diluted sample and does not show any deficiency preceding thrombin in the coagulation cascade
   • TT
   • Clinical chemistry, Thrombocyte /thrombosis
   • https://doi.org…acc.2019.01.005

3. diffusion tensor tractography(English)

   • Medical imaging
   • https://doi.org…1471-2377-14-46

4. difficult-to-treat(English)

   • may refer to elbow, knee, anterior face of the tibia area
   • BD, BV, C/BD, Cal/BD, PAM, PASI, RM, TCS
   • Dermatology, Therapeutic approaches
   • https://doi.org…0261-016-0489-5