In Marvel's Agents of S.H.I.E.L.D. TV series, Dr. Streitan told Coulson that Coulson was dead for days after Loki stabbed him. So, certainly, S.H.I.E.L.D. has tech to revive deads.
The TV series hasn't featured this tech yet, but upcoming episode may reveal it as Skye's life is in danger.
I am unable to wait till the episode broadcast. So, I want to know if S.H.I.E.L.D. has such tech in a canon other than Earth-19999. If yes, what is it? How does it work?