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What is radiation? Radiation is energy. It travels in the form of energy waves or high-speed particles. Radiation can occur naturally or be man-made. ...
What is radon? Radon is a naturally occurring radioactive gas. It is invisible and has no odor or taste. It comes from the normal decay of uranium and ...
A rash is an area of irritated or swollen skin. Many rashes are itchy, red, painful, and irritated. Some rashes can also lead to blisters or patches of ...
What is Raynaud phenomenon? Raynaud phenomenon is a condition that affects your blood vessels (the tubes that your blood flows through). It causes your ...
What is reflux (GER) and GERD? Gastroesophageal reflux (GER), often called reflux, occurs when food or stomach acid flows back from your child's stomach ...
What is reflux (GER) and GERD? Gastroesophageal reflux (GER), often called reflux or spitting up, happens when food or milk comes back up from your baby's ...
What is rehabilitation? Rehabilitation is care that can help you get back, keep, or improve abilities that you need for daily life. These abilities may ...
What are reproductive hazards? Reproductive hazards are substances that affect the reproductive health of men or women. They also include substances that ...
What is respiratory failure? Respiratory failure is a condition in which your blood doesn't have enough oxygen or has too much carbon dioxide. Sometimes ...
What is respiratory syncytial virus (RSV)? Respiratory syncytial virus, or RSV, is a common respiratory virus. It usually causes mild, cold-like symptoms. ...
What are retinal disorders? Retinal disorders are conditions that affect the retina, the thin light-sensitive tissue at the back of your eye. The retina ...
What is rheumatoid arthritis? Rheumatoid arthritis (RA) is a form of arthritis that causes pain, swelling, and stiffness in your joints. RA is an autoimmune ...
What is a rotator cuff? Your rotator cuff is part of your shoulder joint. It's a group of muscles and tendons that holds the top part of your upper arm ...
Around 15% of people in the United States live in rural areas. There are many different reasons why you might choose to live in a rural community. You may want ...
What are opioids? Opioids, sometimes called narcotics, are a type of drug. They include strong prescription pain relievers such as oxycodone, hydrocodone, ...
What is sarcoidosis? Sarcoidosis is a condition in which groups of cells in your immune system form small, red, and swollen (inflamed) lumps. These lumps ...
A scar is a permanent patch of skin that grows over a wound. It forms when your body heals itself after a cut, scrape, burn, or sore. You can also get ...
What is scleroderma? Scleroderma means "hard skin." It's the name of an autoimmune disease that causes inflammation and thickening in the skin and other ...
What is self-harm? Self-harm, or self-injury, is when a person hurts his or her own body on purpose. The injuries may be minor, but sometimes they can ...
What is sepsis? Sepsis is your body's overactive and extreme response to an infection. Sepsis is a life-threatening medical emergency. Without quick treatment, ...
