Running away is not a good idea. Better run towards the dog. Then it will probably turn around, unless it is really sure of itself. In my experience, being convincingly dominant towards dogs is enough to fend them off. Grab something as a weapon if it helps you to be confident. If the dog bites, it will probably only bite very briefly and then let go again. Holding and shaking people like prey is unlikely if it hasn't been conditioned. I don't know what you can do in this case. Try as best you can to injure the animal. You are also dangerous and should let the dog know.