case_images: PMC8286246_01
case_images: PMC8286246_02
case_images: Dynamic changes in the levels of rheumatoid factor antibodies during COVID-19 among five patients.
case_images: JIR-14-3123-g0001.jpg
case_images: PMC8286246_02_JIR-14-3123-g0001.jpg
case_images: f0001
case_images: The dynamic changes of RFs in these five patients are shown in Figure 1.