Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:Current evidence also indicates that shear stress activates two MAP kinases by distinct signaling pathways: activation of ERK is mediated by mechanisms involving Gai-2, protein kinases [Src, focal adhesion kinase (FAK), and protein kinase C-e], and Ras, whereas JNK activation requires Gb/g, phosphatidylinositol 3-kinase-g, tyrosine kinases (Src and FAK), and Ras (11, 14, 15, 22, 37).
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