Influence of EMF and electromagnetic fields combined with an additional alternating electric field (EMF + EF) stimulation on gene expression of human osteoblasts after 3 days. Gene expression levels of osteogenic markers after EMF and EMF + EF in relation to the non-treated control. Data (n=6) are presented in box plots, whereby boxes identify interquartile ranges, horizontal lines within the boxes indicate the median, black dots show the mean and whiskers denote minimum and maximum values. Statistical analysis was conducted by one-way ANOVA (*p<0.05, represents significance of differences between EMF + EF and the controls; #p<0.05, represents significance of differences between EMF and EMF + EF). Target genes are collagen type 1 (Col I), alkaline phosphatase (ALP), osteocalcin (OC), runt-related transcription factor 2 (RUNX-2) and bone sialoprotein (BSP).