RASGRF1 and rheumatoid arthritis: Quantitative analysis of proteins detected by immunoblotting demonstrated that transfection of RA FLS with RasGRF1 cDNA encoding full-length RasGRF1 resulted in the enhanced expression of the 140 kDa (P < 0.01), 98 kDa and 75 kDa (P < 0.05), and 54 kDa (P < 0.05) forms of RasGRF1.