DLL1 and hand, foot and mouth disease: The expression levels of Notch ligands Dll1 (p = 0.000) and Dll4 (p = 0.002) in the peripheral blood of the HFMD group were significantly higher than those of the control group (Figure 1); however, there were no significant differences in Jagged1 and Jagged2 expression levels found between the HFMD and control groups (Figure 1).