Perspiration, however odiferous and uncomfortable, is good. Scientists at Germany's Tuebingen University have discovered an antimicrobial peptide -- a protein that protects the body against attacks from germs -- in human sweat. The new one, Dermcidin, is, according to co-discoverer Birgit Schittek,"the first one known to be produced continuously in the skin." Other types are produced only after injury or infection.