Because of the requirement for special ventilation. utilities and floor strength, separate access, etc., it will almost be prohibitively expensive to have residential mixed into a research building (two basically separate buildings, eg a short "podium" with lab space and a residential tower attached at one corner, could work in theory). It's not completely impossible, however; a mixed-use residential/clinical/research complex had been proposed and approved in Boston since 2003, but the original plan has since been altered after laying dormant for 4 years and the residential component was removed (the project has since stalled during the 2008 recession, like this MaRS building, but since only demolitions were completed and nothing has yet been built, it might still be possible for plans to be changed again and the residential component added back when the economy recovers, but it's doubtful).