Fig. 7
Histopathological images of the tumors on day 30 after treatment from the following experimental groups: a the sham group × 200; 30-min dual-frequency sonication with Hp injection in b one repetition at the first day group (US(150 kHz + 1 MHz) + Hp)0 × 100; c two repetitions at the first and sixth days group (US(150 kHz + 1 MHz) + Hp)0,6 × 100; d three repetitions at the first, sixth, and twelfth days group (US(150 kHz + 1 MHz) + Hp)0,6,12 × 400; e four repetitions at the first, sixth, twelfth, and eighteenth days group (US(150 kHz + 1 MHz) + Hp)0,6,12,18 × 300; and f the fractional treatment group treated by 7.5-min dual-frequency sonication and Hp injection at the first, third, sixth, and ninth days (USfraction (150 kHz + 1 MHz) + Hp)0,3,6,9 × 400 magnification