i work in medicine, im in nursing school and i see a lot of sickness.. and i have dissected animals.. dead animals. I also know how much research goes into giving animals drugs to see the effects, and using it on dead tissue just doesn't work the same as on live tissue. You have to see the long term effects to see if its really safe. Part of the research is giving the mouse the drug over an extended amount of time and monitoring for things like Cancer. They have to make sure it doesnt kill them or cause cancer before they start preforming trials on people. Or would you just like to take a drug that has only been tested on dead tissue? Would you want to be in the test group for a drug to help monitor your blood pressure and then fall over from hypotension? Or die of a heart attack because they have no idea what its going to do to a living being?