Bloody nose: Bleeding from the blood vessels of the nose. The nose is rich in blood vessels and is situated in a vulnerable position on the face. As a result, any trauma to the face can cause bleeding, which may be profuse. Nosebleeds can also occur spontaneously when the nasal membranes dry out, crust, and crack, as is common in dry climates or during winter months, when the air is dry and warm from household heaters. People have increased susceptibility to nosebleeds if they are taking medications that prevent normal blood clotting, such as warfarin (brand name: Coumadin), aspirin, or any anti-inflammatory medication. Other predisposing factors include infection, trauma, allergic and nonallergic rhinitis, hypertension, alcohol abuse, and inherited bleeding problems. Also known as epistaxis.
- Bloody show
Bloody show: Literally, the appearance of blood, a classic sign of impending labor. The bloody show ‘consists of blood-tinged mucus created by extrusion and passage of the mucous plug that filled the cervical canal during pregnancy.
- Bloody sputum
Bloody sputum: Coughed up blood or bloody mucus. Bloody sputum can be caused by infection in the lungs and airways, such as acute bronchitis or pneumonia, or cancer. Whenever bloody sputum is present and cannot be attributed to a curable infectious condition, a complete lung evaluation is warranted, including bronchoscopy, to be certain cancer is […]
- Blot, Northern
Blot, Northern: A technique in molecular biology, used mainly to separate and identify pieces of RNA. Called a Northern blot only because it is similar to a Southern blot (which is named after its inventor, the British biologist M.E. Southern). There is also a Western blot.
- Blot, Southern
Blot, Southern: A test commonly used in molecular biology and genetics, the purpose of the test being to check for a match between DNA molecules. In the Southern blot technique, DNA fragments are separated by a method called agarose gel electrophoresis, transferred (blotted) onto membrane filters, and hybridized with complementary radiolabeled probes. The aim is […]
- Blot, Western
Blot, Western: A technique in molecular biology that is used to separate and identify proteins. It is called a Western blot merely because it is similar to a Southern blot, which was named after its inventor, the British biologist M.E. Southern. For example, the Western blot assay method is commonly used to diagnose Lyme disease.