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What is anesthesia? Anesthesia is the use of medicines to prevent pain during surgery and other procedures. These medicines are called anesthetics. They ...
An aneurysm is a bulge or "ballooning" in the wall of an artery. Arteries are blood vessels that carry oxygen-rich blood from the heart to other parts of ...
Angina is chest pain or discomfort you feel when there is not enough blood flow to your heart muscle. Your heart muscle needs the oxygen that the blood carries. ...
What is angioplasty? Angioplasty is a procedure to improve blood flow in coronary arteries that have become narrow or blocked. Your coronary arteries ...
Wild animals usually avoid people. They might attack, however, if they feel threatened, are sick, or are protecting their young or territory. Attacks by pets ...
Animal diseases that people can catch are called zoonoses. Many diseases affecting humans can be traced to animals or animal products. You can get a disease ...
Your ankle bone and the ends of your two lower leg bones make up the ankle joint. Your ligaments, which connect bones to one another, stabilize and support ...
Ankylosing spondylitis is a type of arthritis of the spine. It causes inflammation between your vertebrae, which are the bones that make up your spine, and in the ...
Anthrax is a disease caused by Bacillus anthracis, a germ that lives in soil. Many people know about it from the 2001 bioterror attacks. In the attacks, someone ...
Antibiotics are medicines that fight bacterial infections. Used properly, they can save lives. But there is a growing problem of antibiotic resistance. It happens ...
What are antibiotics? Antibiotics are medicines that fight bacterial infections in people and animals. They work by killing the bacteria or by making ...
What are antidepressants? Antidepressants are prescription medicines to treat depression. Depression is more than feeling a little sad or "blue" for a ...
Antioxidants are man-made or natural substances that may prevent or delay some types of cell damage. Antioxidants are found in many foods, including fruits and vegetables. ...
What is anxiety? Anxiety is a feeling of fear, dread, and uneasiness. It might cause you to sweat, feel restless and tense, and have a rapid heartbeat. ...
An aneurysm is a bulge or "ballooning" in the wall of an artery. Arteries are blood vessels that carry oxygen-rich blood from the heart to other parts of ...
What is aphasia? Aphasia is a language disorder that makes it hard for you to read, write, and say what you mean to say. Sometimes it makes it hard to ...
What is aplastic anemia? Aplastic anemia is a rare but serious blood disorder. If you have it, your bone marrow doesn't make enough new blood cells. It ...
The appendix is a small, tube-like organ attached to the first part of the large intestine. It is located in the lower right part of the abdomen. It has ...
Of the 206 bones in your body, three of them are in your arm: the humerus, radius, and ulna. Your arms are also made up of muscles, joints, tendons, and ...
An arrhythmia is a problem with the rate or rhythm of your heartbeat. It means that your heart beats too quickly, too slowly, or with an irregular pattern. ...
