1. Molecular Imaging Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892–1002, USA.
2. Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
3. Image Probe Development Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892–3372, USA.