1. Molecular Imaging Center; Department of Radiology; Fourth Affiliated Hospital; Harbin Medical University; Harbin Heilongjiang P. R. China
2. Department of Chemistry and Bio-Imaging Research Center; The University of Georgia; Athens Georgia 30602 USA
3. Center for Molecular Imaging and Translational Medicine; State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics; School of Public Health; Xiamen University; Xiamen P. R. China