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What is bipolar disorder? Bipolar disorder is a mood disorder that can cause intense mood swings: Sometimes you may feel extremely "up," elated, irritable, ...
What is bird flu? Birds, just like people, can get the flu. Another name for bird flu is avian influenza. The viruses that cause bird flu normally only ...
What is birth control? Birth control, also known as contraception, is the use of medicines, devices, or surgery to prevent pregnancy. There are many different ...
What are birth defects? A birth defect is a problem that happens while a baby is developing in the mother's body. Most birth defects happen during the ...
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 ...
What is bone density? Your bones are made of living tissue. To keep them strong, your body breaks down old bone and replaces it with new bone. But when ...
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 ...
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 calcium and why do I need it? Calcium is a mineral, a nutrient that you need (in small amounts) to keep your body healthy. You have more calcium ...
