Medications

Marker gene: A detectable genetic trait or segment of DNA that can be identified and tracked. A marker gene can serve as a flag for another gene, sometimes called the target gene. A marker gene must be on the same chromosome as the target ge...

Nasal decongestant - Medical

Nasal decongestant: A drug that shrinks the swollen membranes in the nose, making it easier to breath. Decongestants can be taken orally or by nasal drops or spray. Nasal decongestants should not be used for more than five days in a row without the d...

Marker chromosome - Medical

Marker chromosome: An abnormal chromosome that is distinctive in appearance but not fully identified. A marker chromosome is not a "marker" of a specific disease. It is a marker chromosome merely in the sense that it can be distinguished under...

Nasal - Medical

Nasal: Having to do with the nose. Nasal drops are intended for the nose, not (for example) the eyes. The word "nasal" came from the Latin "nasus" meaning the nose or snout.Last Editorial Review: 4/27/2011 5:27:15 PM...

Marker - Medical

Marker: A piece of DNA that lies on a chromosome so close to a gene that the marker and the gene are inherited together. A marker is thus an identifiable heritable spot on a chromosome. A marker can be an expressed region of DNA (a gene) or a se...

Mark of Cain - Medical

Mark of Cain: The mark that God set upon Cain, the eldest son of Adam. According to the Book of Genesis in the Bible, God rejected Cain's grain offering while accepting the animal offering of his brother Abel. Out of jealousy, Cain murdered his broth...

Naris - Medical

Naris: One of the two nares, the openings to the nasal cavities that allow air to flow in and out or, more simply, a nostril. Naris is the Latin singular of nares and is less used in medicine than nares.Last Editorial Review: 11/30/2003 Nares: The n...

Nares - Medical

Nares: The nostrils or nasal passages. Nares is the Latin plural of naris, meaning nostril. Nares shares the same root with nose, nostril, nasal, pince-nez, and Nez Perce. Last Editorial Review: 4/27/2011 5:27:15 PM Nasal: Having to do with the nos...

Marinesco-Sjogren syndrome - Medical

Marinesco-Sjogren syndrome: A genetic disorder characterized by very small stature, cerebellar ataxia (wobbliness), cataracts, muscle weakness, hypogonadism (low gonadal function), and developmental and mental retardation. The disease is usually e...

Narcotic antagonist treatment - Medical

Narcotic antagonist treatment: Treatment of narcotic addiction by using a medication that is an antagonist to opiates or any other drug to which a person is addicted. See: Methadone treatment program; Naltrexone treatment program.Last Editorial Revi...

Marijuana - Medical

Marijuana: A very common street and recreational drug that comes from the marijuana plant. The plant that produces marijuana, as is well known, is the hemp plant cannabis sativa. The pharmacologically active ingredient in marijuana is tetra-hydro-c...

Marie-Strumpell disease - Medical

Marie-Strümpell disease: A synonym for ankylosing spondylitis. Named for the French neurologist Pierre Marie (1853-1940) and the German neurologist whose full name was Ernst Adolf Gustav Gottfried von Str¨mpell (1853-1925). See: Ankylosing...

Narcotic - Medical

Narcotic: 1. A drug that causes insensibility or stupor. A narcotic induces narcosis, from the Greek "narke" for "numbness or torpor." 2. A drug such as marijuana which is subject to regulatory restrictions comparable to those for addictive narcotic...

Margaret Mead - Medical

Margaret Mead: See: Mead, Margaret.Last Editorial Review: 11/6/2004 Mead, Margaret: (1901-1978) American anthropologist, author, and social critic. From the publication of her first book, "Coming of Age in Samoa," in 1928, in which she describ...

Narcolepsy - Medical

Narcolepsy: A neurological disorder marked by a sudden recurrent uncontrollable compulsion to sleep. Narcolepsy is often associated with cataplexy (a sudden loss of muscle tone and paralysis of voluntary muscles associated with a strong emotion), sle...

Marfan syndrome - Medical

Marfan syndrome: An inherited disorder of connective tissue characterized by abnormalities of the eyes, skeleton, and cardiovascular system. Myopia (nearsightedness) is the most common eye feature. Displacement of the lens from the center of the pu...

Narcan - Medical

Narcan: Brand name for naloxone.Last Editorial Review: 8/7/2004 Naloxone: A drug that antagonizes morphine and other opiates. Naloxone is a pure opiate antagonist and prevents or reverses the effects of opioids including respiratory depression, seda...

Marburg virus - Medical

Marburg virus: The virus that causes Marburg hemorrhagic fever, a disease which affects both humans and non-human primates. Caused by a genetically unique zoonotic (that is, animal-borne) RNA virus of the filovirus family, its recognition led to th...

Naprosyn - Medical

Naprosyn: See: Naproxen. Last Editorial Review: 3/3/2004...

Naprelan - Medical

Naprelan: See: Naproxen. Last Editorial Review: 3/3/2004...

Marburg disease - Medical

Marburg disease: A severe form of hemorrhagic fever which affects both humans and non-human primates. Caused by a genetically unique zoonotic (that is, animal-borne) RNA virus of the filovirus family, its recognition led to the creation of this vir...

Napiform - Medical

Napiform: A little-used but useful adjective meaning turnip-shaped. Large and round at the top and tapering down sharply and becoming exceedingly slender toward the bottom tip. "A napiform root is one when much swollen at the base, so as to become br...

Marasmus - Medical

Marasmus: Wasting away, as occurs with children who have kwashiorkor. Also called cachexia, is usually a result of protein and calorie deficiency. Last Editorial Review: 4/27/2011 5:27:15 PM...

Mapping, gene - Medical

Mapping, gene: The process of determining the relative positions of genes on a chromosome (or another piece of DNA) and the distances between the genes in linkage units or in physical units.Last Editorial Review: 4/27/2011 5:27:15 PM...

Nannycam - Medical

Nannycam: See: Nanny cam. Last Editorial Review: 7/8/2004 Nanny cam: A camcorder (a video camera and video recorder in one unit) that displays a live feed so that parents can monitor their babysitters. Also known as a nanny-cam or nannycam. La...

Mapping - Medical

Mapping: Charting the location of genes on chromosomes. Last Editorial Review: 4/27/2011 5:27:15 PM...

Nanny cam - Medical

Nanny cam: A camcorder (a video camera and video recorder in one unit) that displays a live feed so that parents can monitor their babysitters. Also known as a nanny-cam or nannycam. Last Editorial Review: 7/8/2004...

Maple syrup urine disease - Medical

Maple syrup urine disease: Hereditary disease due to deficiency of an enzyme involved in amino acid metabolism, characterized by urine that smells like maple syrup. The three branched-chain amino acids: (leucine, isoleucine, and valine) cannot be me...

Nanny - Medical

Nanny: A woman employed full-time to take care of one or more children in a family home. Nanny is the diminutive of Ann or Anne and a nanny is also a female goat but the origin of the term nanny as a woman caring for children is conjectural. The male...

Map-dot-fingerprint type corneal dystrophy - Medical

Map-dot-fingerprint type corneal dystrophy: A disorder in which the cornea (the normally clear front window of the eye) shows geographic map-like lines, dots (or microcysts), and grayish fingerprint lines on examination with a slit-lamp, a device th...