Fig. 6From: The use of 5-fluorouracil-loaded nanobubbles combined with low-frequency ultrasound to treat hepatocellular carcinoma in nude miceDetection of tumor cell apoptosis with TUNEL staining (original magnification ×400). The number of apoptotic tumor cells in each of the four groups varied (a saline; b 5-FU-loaded nanobubbles; c 5-FU-loaded nanobubbles with non-low-frequency ultrasound; d 5-FU-loaded nanobubbles with low-frequency ultrasound)Back to article page