PURPOSE: To enable the suppression of breeding of germ on the surface of an apparatus body effectively by arranging a means to apply an electric stimulation on an outer surface of the apparatus body to be embedded into a human body.

CONSTITUTION: When an AC voltage or a DC voltage is applied to an external metal part 9 and an internal metal section 10 of a box body 1 from a power source 12, electric stimulation is applied to the surface of the box body 1. Then, when the electric stimulation is applied to the surface of the box body 1, growth of germs is inhibited to prevent breeding of the germs on the surface of the box body 1. One pole of the power source 12 provided within the box body 1 is connected to the external metal part 9 of the box body 1 while the other pole is connected to the internal metal part 10 to apply electric stimulation to the surface of the box body 1. A coil 16 may be provided within the box body 1 in place of the power source 12 and an electromagnetic wave is applied to the coil 16 sent from an electromagnetic generation means 17 provided outside a human body thereby applying the electric stimulation to the surface of the box body 1.