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What is heart surgery? Heart surgery can correct certain heart problems when other treatments haven't worked or can't be used. In some cases, heart surgery ...
A heart transplant removes a damaged or diseased heart and replaces it with a healthy one. The healthy heart comes from a donor who has died. It is the ...
What are heart valve diseases? Heart valve disease happens when one or more of your heart valves don't work well. Your heart has four valves: the tricuspid, ...
Heartburn is a painful burning feeling in your chest or throat. It happens when stomach acid backs up into your esophagus, the tube that carries food from your ...
Your body normally cools itself by sweating. During hot weather, especially when it is very humid, sweating just isn't enough to cool you off. Your body temperature ...
Heel problems are common and can be painful. Often, they result from too much stress on your heel bone and the tissues that surround it. That stress can come ...
Helicobacter pylori (H. pylori) is a type of bacteria that causes infection in the stomach. It is the main cause of peptic ulcers, and it can also cause gastritis ...
Hemochromatosis is a disease in which too much iron builds up in your body. Your body needs iron but too much of it is toxic. If you have hemochromatosis, you absorb ...
What is hemophilia? Hemophilia is a rare bleeding disorder in which the blood does not clot properly. This can lead to problems with bleeding too much ...
Viral hemorrhagic fevers (VHFs) are a group of illnesses caused by four families of viruses. These include the Ebola and Marburg, Lassa fever, and yellow fever ...
A stroke is a medical emergency. There are two types - ischemic and hemorrhagic. Hemorrhagic stroke is the less common type. It happens when a blood vessel ...
What are hemorrhoids? Hemorrhoids are swollen, inflamed veins around your anus or the lower part of your rectum. There are two types: External hemorrhoids, ...
What is hepatitis? Hepatitis is inflammation of the liver. Inflammation is swelling that happens when tissues of the body are injured or infected. It ...
What is hepatitis? Hepatitis is inflammation of the liver. Inflammation is swelling that happens when tissues of the body are injured or infected. It ...
What is hepatitis? Hepatitis is inflammation of the liver. Inflammation is swelling that happens when tissues of the body are injured or infected. It ...
What is hepatitis C? Hepatitis is inflammation of the liver. Inflammation is swelling that happens when tissues of the body are injured or infected. Inflammation ...
An herb is a plant or plant part used for its scent, flavor, or therapeutic properties. Herbal medicines are one type of dietary supplement. They are sold ...
A hernia happens when part of an internal organ or tissue bulges through a weak area of muscle. Most hernias are in the abdomen. There are several types ...
Your backbone, or spine, is made up of 26 bones called vertebrae. In between them are soft disks filled with a jelly-like substance. These disks cushion the ...
What is heroin? Heroin is an illegal, very addictive opioid drug. It's made from morphine, which comes from the seedpod of opium poppy plants. These plants ...
