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 cannot find your PD on your prescription: 1  Have it measured at an optical shop, charges may apply. 2  Contact the optical store where you had previously purchased prescription glasses. They have definitely measured your PD for it. 3  Your previous ophthalmologist may have a record of your PD.