1. Department of Urology, Affiliated Hospital of Hebei University, Baoding, Hebei 071000, P. R. China
2. No 1 Department of General Surgery, People’s Hospital of Rongcheng, Baoding, Hebei 071700, P. R. China
3. Faculty of Chemical Engineering Technology, 02600 Arau, Universiti Malaysia Perlis, Perlis, Malaysia
4. Institute of Nano Electronic Engineering, 01000 Kangar, Universiti Malaysia Perlis, Perlis, Malaysia