But new Johns Hopkins research in mice suggests that neural stem cells, the bodyâs source of new brain cells, are resistant to radiation, and can be roused from a hibernation-like state to reproduce and generate new cells able to migrate, replace injured cells and potentially restore lost function.
Pupillary Distance (PD) You'll need to know your PD if you want to order glasses from EyeBuyDirect. Don't worry if your glasses prescription doesn't include your PD, we can show you how to measure it by yourself. How to measure your pd
If you see an âaddâ on your prescription, that tells the optician that a person needs an added magnifying power added to the lens. They typically range from +0.75 to +3.00 diopters. So now when you see a slip of paper given to you by your eye doctor that reads. OD = -4.00 SPH + 3.00 add.