Aparna Visweswaran, M.D., Hong Liu, Ph.D., Laurie L. Fajardo, M.D., Gia A. DeAngelis, M.D.

Department of Radiology, University of Virginia Health Sciences Center, Charlottesville, VA 22908, USA

Received 05/15/96; Accepted 07/08/96; On-line 08/01/96

ACKNOWLEDGMENTS

This work was supported in part by the Whitaker Foundation (Biomedical Engineering Research Grant), and by a NIH grant CA69043 (to H Liu).