CD34 and neoplasm: The characteristics of hypoxia (pimonidazole), tumor blood perfusion (Hoechst 33342), microvessel formation (CD34) and morphology [hematoxylin-eosin (HE)] of tumors were examined and compared (Figures 2 and 3) in 0 Gy, 10 Gy and 20 Gy pre-irradiated mice.