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MedlinePlus is an online health information resource for patients and their families and friends. It is a service of the National Library of Medicine (NLM), the world's largest medical library, which is part of the National Institutes of Health (NIH). Learn more about MedlinePlus
- FEATURED TOPIC
- Rheumatoid Arthritis
- Rheumatoid arthritis (RA) is a form of arthritis that causes pain, swelling, and stiffness in your joints. Your risk increases as you become an older adult.
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