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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 ...
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. ...
What is a stillbirth? If you lose a fetus at or after the 20th week of pregnancy, it's called a stillbirth. A stillbirth can occur before or during delivery ...
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 ...
Strep is short for Streptococcus, a type of bacteria. There are several types. Two of them cause most of the strep infections in people: group A and group ...
What is stress? Stress is how your brain and body respond to a challenge or demand. When you are stressed, your body releases certain hormones. Hormones ...
What is a stroke? A stroke happens when there is a loss of blood flow to part of the brain. Your brain cells cannot get the oxygen and nutrients they ...
What is stroke rehabilitation? Stroke rehabilitation is a program for people who have had a stroke. A stroke happens when there is a loss of blood flow ...
What is stuttering? Stuttering is a speech disorder. It involves interruptions in the flow of speech. These interruptions are called disfluencies. They ...
What is sudden cardiac arrest (SCA)? Sudden cardiac arrest (SCA) is a condition in which the heart suddenly stops beating. When that happens, blood stops ...
Sudden infant death syndrome (SIDS) is the sudden, unexplained death of an infant younger than one year old. Some people call SIDS "crib death" because many babies ...
What is suicide? Suicide is the taking of one's own life. It is a death that happens when someone harms themselves because they want to end their life. ...
