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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, ...
What is sexual assault? Sexual assault is any kind of sexual activity, contact, or experience that happens without your consent. That means the sexual ...
What is shingles? Shingles (herpes zoster) is an infection that causes a painful rash. It is caused by the varicella-zoster virus (VZV). This is the same ...
What is sickle cell disease (SCD)? Sickle cell disease (SCD) is a group of inherited red blood cell disorders. If you have SCD, there is a problem with ...
What is Sjogren's syndrome? Sjogren's syndrome, also called Sjogren's disease, is a chronic (long-lasting) autoimmune disease. When you have an autoimmune ...
What are skin infections? Your skin is your body's largest organ. It has many different functions, including covering and protecting your body. It helps ...
Sleep apnea is a common disorder that causes your breathing to stop or get very shallow. Breathing pauses can last from a few seconds to minutes. They may ...
What is sleep? Sleep is a complex biological process. While you are sleeping, you are unconscious, but your brain and body functions are still active. ...
What are the health effects of smoking? There's no way around it; smoking is bad for your health. It harms nearly every organ of the body, even some that ...
Your soft tissues connect, support, or surround other tissues. Examples include your muscles, tendons, fat, and blood vessels. Soft tissue sarcoma is a cancer ...
Your spinal cord is a bundle of nerves that runs down the middle of your back. It carries signals back and forth between your body and your brain. A spinal ...
What is spinal muscular atrophy (SMA)? Spinal muscular atrophy (SMA) is a group of genetic diseases that damages and kills motor neurons. Motor neurons ...
A sprain is a stretched or torn ligament. Ligaments are tissues that connect bones at a joint. Falling, twisting, or getting hit can all cause a sprain. ...
What are Staphylococcal (staph) infections? Staphylococcus (staph) is a group of bacteria. There are more than 30 types. A type called Staphylococcus aureus ...
What is cholesterol? Cholesterol is a waxy, fat-like substance that's found in all the cells in your body. Your body needs some cholesterol to work properly. ...
The stomach is an organ between the esophagus and the small intestine. It mixes food with stomach acid and helps digest protein. Stomach cancer mostly affects ...
