Abstract: An apparatus for grinding specimens, comprises a container, a grinder, a closure for the container, and a seal contained in the closure. The container has an interior grinding surface and contains an opening through which specimens are introduced for grinding. The grinder has a grinding head and an actuator arm extending from the grinding head. The grinding head is adapted to engage the interior grinding surface of the container. Grinding is effected by moving the grinding head against the grinding surface, using the actuator arm. The closure is adapted to close the container and enclose the grinding head therein. The closure contains a passage through which the actuator arm extends when the closure is enclosing the grinding head. The seal is contained in the closure and coaxially aligned with the passage of the closure, such that the actuator arm slidably engages the seal when the arm passes through the closure.

Abstract: An injection shield for protecting a person's hand during the injection of a needle into a rodent's tail. The shield comprises a frame which includes a coupler for a rodent restrainer, and contains an opening for a rodent's tail. The frame includes an injection surface on an injection side of the frame. The coupler is adapted to receive and releasably secure the restrainer in an orientation that permits the tail to be placed on the injection surface of the frame. The opening is dimensioned to allow the tail to pass through the frame, from the injection side to a shielded side. The opening is a sufficient distance from the coupler to allow the tail to extend through the opening and be grasped by the person's hand or otherwise secured. A method of protecting a person's hand during the injection of a needle into a rodent's tail is also contemplated by the present invention.