Glossary N's

narcotic analgesic

Definition:type of painkiller that blocks the transmission of pain signals in the brain; often causes tolerance (the need for higher amounts of the drug to produce the same effect) and drug dependence

narcotic

Definition:addictive substance that blunts the senses; can cause confusion, stupor, coma, and death with increased dosages

nares

Definition:the nostrils or nasal openings

nasal septum

Definition:section of the nose that divides the left and right nostrils; made of cartilage and bone and covered by a mucous membrane

nasal

Definition:pertaining to the nose

nasopharynx

Definition:upper part of the pharynx, located behind the nose

nausea

Definition:feeling the need to vomit

nebulizer

Definition:instrument that provides a drug in a misted form through a facemask; used for severe asthma attacks and for children who have asthma but cannot use an inhaler

necrosis

Definition:death of tissue cells

needle aspiration

Definition:use of a thin, hollow needle and syringe to remove body fluid for examination

needle biopsy

Definition:use of a hollow, wide-diameter needle to remove a sample of tissue for examination

nephrectomy

Definition:surgical removal of one or both kidneys

nephritis

Definition:inflammation of one or both kidneys because of an infection, an abnormal immune system response, or a metabolic disorder

nephrolithotomy

Definition:surgical removal of a kidney stone

nephrons

Definition:tiny filtering units of the kidney

nephrosclerosis

Definition:replacement of normal kidney structures with scar tissue

nephrostomy

Definition:surgical placement of a tube into the kidney to drain urine

nephrotic syndrome

Definition:loss of protein from nephrons

nerve block

Definition:dulling of sensation in an area of the body by injecting a painkiller into or around a nerve leading to that section of the body

nerve cell

Definition:basic unit of the nervous system; transmits chemical messages throughout the body

nerve compression

Definition:pressure on a nerve, which can cause nerve damage and muscle weakness

nerve

Definition:bundle of fibers that transmit electrical messages between the brain and areas of the body; these messages convey sensory or motor function information

nervous system

Definition:the complete system of nerve tissues in the body, consisting of the brain, brainstem, spinal cord, nerves and ganglia

neural

Definition:pertaining to a nerve or the nerves

neuralgia

Definition:pain along the course of a nerve caused by irritation or damage to the nerve

neuritis

Definition:inflammation of a nerve, often characterized by pain, numbness, or tingling; also used to describe nerve damage and disease from causes other than inflammation

neuro

Definition:prefix indicating a nerve or relating to a nerve or the nervous system

neurofibromatosis

Definition:condition in which connective tissue tumors occur on nerves in the skin

neuroleptic

Definition:an antipsychotic drug

neurologic

Definition:pertaining to the nervous system or neurology

neurology

Definition:branch of medicine dealing with diagnosis and treatment of disorders of the nervous system

neuroma

Definition:noncancerous tumor occurring in nerve tissue

neuromuscular blocking drugs

Definition:group of very powerful drugs that completely relax most of the muscles in the body, temporarily disabling movement; patient must be on breathing machine as breathing muscles are affected

neuron

Definition:nerve cell

neuropathy

Definition:disease, inflammation, or damage to the nerves connecting the brain and spinal cord to the rest of the body

neurosis

Definition:relatively mild emotional disorders, such as mild depression and phobias

neurotransmitters

Definition:chemicals that transfer messages from one nerve cell to another or from a nerve cell to a muscle cell

neutrophil

Definition:type of white blood cell

National Institutes of Health (NIH)

Definition:nonregulatory United State's federal agency with oversight of research activities it funds

nitrates

Definition:group of drugs that widen blood vessels; used to treat insufficient blood supply to the heart (angina pectoris) and reduced pumping efficiency of the heart (heart failure)

nocturia

Definition:urination or a sleep-disturbing need to urinate during the night

nocturnal

Definition:occurring during or active at night

noninvasive

Definition:descriptive of medical procedures that do not enter or penetrate the body; also refers to noncancerous tumors that do not spread to other sections of the body

norepinephrine

Definition:hormone that regulates blood pressure by causing blood vessels to narrow and the heart to beat faster when blood pressure drops

nosocomial infection

Definition:infection acquired in a hospital

nurse practitioner (NP)

Definition:a registered nurse specially trained to provide an expanded role in the provision of medical care under the supervision of a doctor

nonsteroidal anti-inflammatory drugs (NSAID)

Definition:group of drugs that relieve pain and reduce inflammation

nursing home

Definition:facility which provides nursing supervision and limited medical care to people who do not require hospitalization; also called an extended care facility

nuclear medicine

Definition:use of weakly radioactive material as a type of contrast material and a radiation detection camera to make images of the inside of the body

numbness

Definition:lack of sensation in a part of the body because of interruption of nerve impulses

nutrient

Definition:any substance that the body can use to maintain its health

nutrition

Definition:collectively, all nutrients and the physical and chemical processes by which nutrients are converted into body tissue

nystagmus

Definition:persistent, rapid, involuntary movement of the eyes

nitroglycerin

Definition:drug used to widen blood vessels, including use as treatment for insufficient blood supply to the heart (angina pectoris) and the reduced pumping efficiency of the heart (heart failure)

nasogastric tube (NG)

Definition:thin, plastic tube that is inserted through the nose, down the esophagus, and into the stomach; used to drain, wash, or take samples from the stomach, or to feed very sick patients who cannot eat; also called NG tube