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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 ...
MRSA stands for methicillin-resistant Staphylococcus aureus. It causes a staph infection (pronounced "staff infection") that is resistant to several common ...
Multiple myeloma is a cancer that begins in plasma cells, a type of white blood cell. These cells are part of your immune system, which helps protect the body ...
Multiple sclerosis (MS) is a nervous system disease that affects your brain and spinal cord. It damages the myelin sheath, the material that surrounds and protects ...
Mumps is an illness caused by the mumps virus. It starts with: Fever Headache Muscle aches Tiredness Loss of appetite After that, the salivary glands under ...
What are muscle cramps? Muscle cramps are sudden, involuntary contractions or spasms in one or more of your muscles. They are very common and often occur ...
Your muscles help you move and help your body work. Different types of muscles have different jobs. There are many problems that can affect muscles. Muscle ...
What is muscular dystrophy (MD)? Muscular dystrophy (MD) is a group of more than 30 genetic diseases. They cause weakness of the muscles. Over time, the ...
What is myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)? Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a serious, long-term ...
What is myasthenia gravis? Myasthenia gravis, sometimes called MG, is a chronic (long-lasting) disease that causes weakness in your voluntary muscles. ...
Mycobacteria are a type of germ. There are many different kinds. The most common one causes tuberculosis. Another one causes leprosy. Still others cause infections ...
Your 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 ...
Myositis means inflammation of the muscles that you use to move your body. An injury, infection, or autoimmune disease can cause it. Two specific kinds are polymyositis ...
Your toenails and fingernails protect the tissues of your toes and fingers. They are made up of layers of a hardened protein called keratin, which is also ...
Your paranasal sinuses are small hollow spaces around the nose. They are lined with cells that make mucus, which keeps your nose from drying out. The nasal ...
What are nausea and vomiting? Nausea is when you feel sick to your stomach, as if you are going to throw up. Vomiting is when you throw up.What causes ...
Any part of your neck - muscles, bones, joints, tendons, ligaments, or nerves - can cause neck problems. Neck pain is very common. Pain may also come from your ...
Neural tube defects are birth defects of the brain, spine, or spinal cord. They happen in the first month of pregnancy, often before a woman even knows that ...
What is neuroblastoma? Neuroblastoma is a type of cancer that forms in nerve cells called neuroblasts. Neuroblasts are immature nerve tissue. They normally ...
