A medical image segmentation apparatus for segmenting one series obtained by continuous imaging of plural parts into plural series with respect to each part for easy interpretation of an image interpreter. The central core is formed from a main matrix that contains nanoparticles doped with at least one rare earth element. The entry structure also has means for retaining a first attractant. The radio network control device and the user station have a service specific key that is preferably valid for several user stations, or in other words, the service specific key is not user specific.