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What are HIV and AIDS? HIV stands for human immunodeficiency virus. It harms your immune system by destroying a type of white blood cell that helps your ...
What is lung cancer? Lung cancer is cancer that forms in tissues of the lung, usually in the cells that line the air passages. It is the leading cause ...
What is lupus? Lupus is a chronic (long-lasting) type of autoimmune disease.Autoimmune diseases happen when your immune system attacks healthy cells and ...
What is Lyme disease? Lyme disease is a bacterial infection you get from the bite of an infected tick. At first, Lyme disease usually causes symptoms ...
Lymphoma is a cancer of a part of the immune system called the lymph system. There are many types of lymphoma. One type is Hodgkin disease. The rest are called ...
What is a mammogram? A mammogram is an x-ray picture of the breast. Health care providers use mammograms to look for early signs of breast cancer. There ...
What is marijuana? Marijuana is a green, brown, or gray mix of dried, crumbled parts from the marijuana plant. The plant contains chemicals which act ...
Children aren't just small adults. It is especially important to remember this when giving medicines to children. Giving a child the wrong dose or a medicine ...
Melanoma is the most serious type of skin cancer. Often the first sign of melanoma is a change in the size, shape, color, or feel of a mole. Most melanomas have ...
What is meningococcal disease? Meningococcal disease is the name for any illness that is caused by Neisseria meningitidis bacteria (also called meningococcal ...
What is menopause? Menopause is the time in your life when you stop having your period and can no longer get pregnant. You have reached menopause when ...
What are mental disorders? Mental disorders (or mental illnesses) are conditions that affect your thinking, feeling, mood, and behavior. They may happen ...
What is mental health? Mental health includes our emotional, psychological, and social well-being. It affects how we think, feel, and act as we cope with ...
What is metabolic syndrome? Metabolic syndrome is the name for a group of risk factors for heart disease, diabetes, and other health problems. You can ...
What are migraines? Migraines are a recurring type of headache. They cause moderate to severe pain that is throbbing or pulsing. The pain is often on ...
What is the mitral valve? The mitral valve is one of the four valves in your heart. Heart valves have flaps that open and close. The flaps make sure that ...
What are mobility aids? Mobility aids help you walk or move from place to place if you have a disability or an injury. Types of mobility aids can include: ...
Mosquitoes are insects that live all over the world. There are thousands of different species of mosquitoes; about 200 of those live in the United States. Female ...
What is mpox? Mpox, which used to be called monkeypox, is a disease caused by the monkeypox virus. This virus is in the same family of viruses as the ...
Magnetic resonance imaging (MRI) uses a large magnet and radio waves to look at organs and structures inside your body. Health care professionals use MRI scans ...