Affiliation: | Department of Microbiology and Immunology, Sherman Fairchild Science Building, Stanford University School of Medicine, 299 Campus Drive, Stanford, California 94305; Department of Mechanical Engineering and Applied Mechanics, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6315; and Department of Anesthesiology and Critical Care, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104 |