The ornamental design for a x-ray tube for medical use, as shown and described.
FIG. 1 is a perspective view of a x-ray tube for medical use showing our new design,
FIG. 2 is a front elevational view thereof,
FIG. 3 is a rear elevational view thereof,
FIG. 4 is a top plan view thereof,
FIG. 5 is a bottom plan view thereof; and,
FIG. 6 is a left side elevational view thereof, a right side elevational view being a mirror image thereof.
The broken lines illustrate portions of the x-ray tube for medical use that form no part of the claimed design. The broken lines form no part of the claimed design.