Display screen or portions thereof of portable medical endoscope operating unit with transitional graphical user interface

FIG. 1 is a front view of a display screen or portions thereof of portable medical endoscope operating unit with transitional graphical user interface, showing my new design;

FIG. 2 is a rear view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a bottom view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a right side view thereof;

FIG. 7 is an enlarged, partial top view thereof showing a first image; and,

FIG. 8 is a second image thereof.

The evenly spaced broken lines in the figures show a display screen or portions thereof and a portable medical endoscope or portions thereof, and form no part of the claimed design. The dot-dash broken lines in the figures show content within a graphical user interface and form no part of the claimed design. The appearance of the display screen or portions thereof of portable medical endoscope operation unit with transitional graphical user interface transitions between the images shown in FIGS. 7 and 8 . The process or period in which one image transitions to another forms no part of the claimed design.