The invention involves immersing a mammalian tissue or cultured tissue equivalent in {TAIL ~ a cryoprotectant solution}, agitating {HEAD ~ 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 
The invention involves immersing a mammalian tissue or cultured tissue equivalent in { TAIL ~ a cryoprotectant solution } , agitating { HEAD ~ 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
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD 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