Fig. 4From: Effects of the surface charge of polyamidoamine dendrimers on cellular exocytosis and the exocytosis mechanism in multidrug-resistant breast cancer cellsThe effects of different ABC transporter inhibitors on the exocytosis of PAMAM dendrimers. The control samples were cells without inhibitor pretreatment. All values are relative to the control. * indicates P < 0.05 vs. the control group, ** indicates P < 0.01 vs. the control group; mean ± SD, n = 3Back to article page