What is the best way to remove matted fur? My new kitty has med length fur and it has been long neglected. I was sitting her on my lap and brushing her with a slicker brush when she nipped my hand. Didn't bite me, just put her teeth on me and gave me a warning look. She has such expressive eyes. Anyways, I know it hurts her, but I don't know how else to remove these matts. Any ideas?