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What are sexually transmitted infections (STIs)? Sexually transmitted infections (STIs) are infections that are passed from one person to another through ...
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 ...
Shock happens when not enough blood and oxygen can get to your organs and tissues. It causes very low blood pressure and may be life-threatening. It often ...
Your shoulder joint is composed of three bones: the clavicle (collarbone), the scapula (shoulder blade), and the humerus (upper arm bone). Your shoulders are ...
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 ...
Sinusitis means your sinuses are inflamed. The cause can be an infection or another problem. Your sinuses are hollow air spaces within the bones surrounding the ...
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 ...
Your skin changes as you age. You might notice wrinkles, age spots and dryness. Your skin also becomes thinner and loses fat, making it less plump and smooth. ...
Skin cancer is the most common form of cancer in the United States. The two most common types are basal cell cancer and squamous cell cancer. They usually ...
What does your skin do? Your skin is your body's largest organ. It covers the entire outside of your body. There are many ways that your skin protects ...
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 ...
Pigmentation means coloring. Skin pigmentation disorders affect the color of your skin. Your skin gets its color from a pigment called melanin. Special cells in the ...
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. ...
Your small intestine is the longest part of your digestive system - about twenty feet long! It connects your stomach to your large intestine (or colon) and folds ...
Smallpox is a disease caused by the Variola major virus. Some experts say that over the centuries it has killed more people than all other infectious diseases ...
Many people who chew tobacco or dip snuff think it's safer than smoking. But you don't have to smoke tobacco for it to be dangerous. Chewing or dipping carries ...
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 ...
Smoking cigarettes has many health risks for everyone. However, the younger you are when you start smoking, the more problems it can cause. People who start ...
Snoring is the sound you make when your breathing is blocked while you are asleep. The sound is caused by tissues at the top of your airway that strike each ...
