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Bleeding is the loss of blood. It can be external, or outside the body, like when you get a cut or wound. It can also be internal, or inside the body, like when ...
Normally, if you get hurt, your body forms a blood clot to stop the bleeding. For blood to clot, your body needs cells called platelets and proteins known as clotting ...
Your blood is made up of liquid and solids. The liquid part, called plasma, is made of water, salts, and protein. Over half of your blood is plasma. The solid ...
What is a blood clot? A blood clot is a mass of blood that forms when platelets, proteins, and cells in the blood stick together. When you get hurt, your ...
What is blood glucose? Blood glucose, or blood sugar, is the main sugar found in your blood. It is your body's primary source of energy. It comes from ...
What are blood thinners? Blood thinners are medicines that prevent blood clots from forming. They do not break up clots that you already have. But they ...
Every year, millions of people in the United States receive life-saving blood transfusions. During a transfusion, you receive whole blood or parts of blood ...
What are body lice? Body lice (also called clothes lice) are tiny insects which live and lay nits (lice eggs) on clothing. They are parasites, and they ...
Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains immature cells, called stem cells. The stem cells ...
A brain aneurysm is an abnormal bulge or "ballooning" in the wall of an artery in the brain. They are sometimes called berry aneurysms because they are ...
What is breast cancer? Breast cancer is a cancer that starts in breast tissue. It happens when cells in the breast change and grow out of control. The ...
What is bullying? Bullying is when a person or group repeatedly harms someone on purpose. It can be physical, social, and/or verbal. It is harmful to ...
A bursa is a small, fluid-filled sac that acts as a cushion between a bone and other moving parts, such as muscles, tendons, or skin. Bursitis occurs when ...
What is C. diff? C. diff is a bacterium that can cause diarrhea and more serious intestinal conditions such as colitis. You may see it called other names, ...
What is caffeine? Caffeine is a bitter substance that occurs naturally in more than 60 plants including: Coffee beans Tea leaves Kola nuts, which are ...
What is cancer chemotherapy? Cancer chemotherapy is a type of cancer treatment. It uses medicines to destroy cancer cells. Normally, the cells in your ...
Cancer is a group of related diseases. In all types of cancer, some of the body's cells begin to divide without stopping and spread into surrounding tissues. ...
Learning to live with cancer Cancer is a common disease. Almost 40 percent of Americans will be diagnosed with cancer during their lifetimes. Even though ...
What are carbohydrates? Carbohydrates, or carbs, are sugar molecules. Along with proteins and fats, carbohydrates are one of three main nutrients found ...
What is a caregiver? A caregiver gives care to someone who needs help taking care of themselves. The person who needs help may be a child, an adult, or ...
