High prevalence of systemic lupus erythematosus in 78 myasthenia gravis patients: a clinical and serologic study - Sthoeger, Z; Neiman, A; Elbirt, D; Zinger, H; Magen, E; Burstein, R; Eitan, S; Abarbanel, J; Mozes, E (AmJ Med Sci, 2006)