{HEAD ~ The invention} involves immersing {TAIL ~ a mammalian tissue} or cultured tissue equivalent in a cryoprotectant solution, agitating the cryoprotectant solution and the immersed tissue to achieve effective penetration of the cryoprotectant solution into the tissue, and then freezing the tissue at a very slow freezing rate at 0.3° C. or less/min 
involves immersing
{ HEAD ~ The invention } involves immersing { TAIL ~ a mammalian tissue } or cultured tissue equivalent in a cryoprotectant solution , agitating the cryoprotectant solution and the immersed tissue to achieve effective penetration of the cryoprotectant solution into the tissue , and then freezing the tissue at a very slow freezing rate at 0.3 ° C. or less / min
HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH