Sentence:  These registries are sponsored by 18 national medical , dental , and veterinary societies and <WSD>have</WSD> as their mission the assembling of selected cases of interest to military medicine and of establishing through the mechanism of follow-up of living patients the natural history of various diseases of military-medical importance . 
Meaning of the word marked with <WSD> tags:  have or possess, either in a concrete or an abstract sense