The association between interleukin-6 promoter polymorphisms and rheumatoid arthritis by ethnicity: A meta-analysis of 33 studies Blanca T. Pacheco-Soto, Leonardo M. Porchia, William C. Lara-Vazquez, Enrique Torres-Rasgado, Ricardo Perez-Fuentes, M. Elba Gonzalez-Mejia

Systematic review and meta-analysis of the efficacy and safety of leflunomide and methotrexate in the treatment of rheumatoid arthritis Roberto Alfaro-Lara, Hector Fabricio Espinosa-Ortega, César Alejandro Arce-Salinas

Interaction between angiotensin-converting enzyme gene rs4343 polymorphism, environment factors, and angiotensin II level on susceptibility to knee osteoarthritis Basma Mohammed Mohammed Ali Elnaggar, Nashwa Mohamed Abd Elbaky, Eman Salah Albeltagy, Hala Mohamed El Zomor