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Rheumatoid arthritis (RA) is the most common inflammatory arthritis, affecting 0.5% to 1% of the population worldwide. It is characterized by joint swelling, joint tenderness, and destruction of synovial joints, leading to severe disability and premature mortality. Although RA is properly considered a disease of the joints, abnormal immune responses can cause a variety of extra-articular manifestations. In some cases, production of rheumatoid factor (RF) with the formation of immune complexes that fix complement contributes to extra-articular findings. So this work is benefit for both physician and researchers that aim to understand the pathogenesis and etiology of the rheumatoid arthritis and to test a novel antirheumatic drugs or agents.

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Abbas Sabbar Dakhil, Ph.D in Medical Physiology Date of birth:1980 Address:Al-Diwaniyah,Iraq Employment:Al-Qadisyiah University/College of Medicine, physiology Dept.

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