The phrase "distal portion" refers to the part of an object that is farthest away from the center or point of reference. It describes the end or tip of something, usually in relation to another part that is closer or more central. Full definition
Juice culture is still the gold standard for the diagnosis of SIBO, but it is technically difficult, time - consuming and expensive, and it may still not identify all cases of SIBO (for example when this is in the more distal portions of the small intestine or in isolated pockets). (epi4dogs.com)
But those same authors also wrote this: «Retrapping success for feral cats probably was underestimated because cats were marked after neutering by removal of a small distal portion of the pinna and ear - tipped cats usually were released from cages without counting.» (voxfelina.com)
At the same time, distal portion of the surface could have retained liquid water. (sciencedaily.com)