. "Referring to FIG. 4A, shown is a schematic drawing illustrating a top view of a barrel 200 for a hollow needle assembly according to the second embodiment of the invention; FIG. 4B illustrates a left side-view of the apparatus shown in FIG. 4A; FIG. 4C illustrates a cross-sectional view through the apparatus shown in FIG. 4A along line C-C; FIG. 4D illustrates a right side-view of the apparatus sh" . . .