A filter device includes a casing having an inlet for introducing fluid and an outlet for discharging fluid, and a filtering element disposed between the inlet and the outlet. At present, microinjection of mitochondria into cells can only process one cell at a time, and therefore, this technique is limited to embryo related research and relevant applications. The first low battery threshold indicates a low battery condition of the remote control. The dot-like structure is bonded to oxygen, and oxygen increases on an interface between the p contact layer and the ITO electrode. In accordance with the invention, a universal structural element in the form of a profile body, having preferably a substantially square cross-section, comprises on all longitudinal sides undercut grooves that are connected on the end sides by means of intersecting undercut grooves with preferably the same cross-section.