patrick.net

http://www.newscientist.com/article/dn27593-fetal-cells-injected-into-a-mans-brain-to-cure-his-parkinsons.html#.VWYz2Nq9KSM

What these trials overlooked is that it takes several years for fetal cells to "bed in" and connect properly to the recipient's brain. Many Swedish and North American recipients improved dramatically, around three years or more after the implants long after the trials had finished. "In the best cases, patients who had the treatment pretty much went back to normal," says Barker.