Glossary: N
- narcissistic personality disorder
persons with this disorder present severely overly-inflated feelings of self-worth, grandiosity, and superiority over others. Persons with narcissistic personality disorder often exploit others who fail to admire them, and are overly sensitive to criticism, judgment, and defeat.
- nasal
relating to the nose.
- National Cancer Institute
The US government agency for cancer research and information.
- nausea
a feeling or sensation leading to the urge to vomit.
- near point of accommodation
the closest point in front of the eyes that an object may be clearly focused.
- near point of convergence
the maximum extent the two eyes can be turned inward.
- necrosis
death of tissue.
- needle aspiration (of the breast)
uses a thin needle and syringe to collect tissue or drain a lump after using a local anesthetic.
- needle biopsy
use of a needle to extract tissue, cells, or fluid for microscopic examination.
- needle biopsy (of the breast)
a procedure to remove a small piece of breast tissue using a needle with a special cutting edge, after using a local anesthetic.
- neoadjuvant therapy
treatment such as chemotherapy, radiation therapy, or hormone therapy which is given before the primary treatment.
- neoplasm
any abnormal growth of new tissue; a proliferation of cells no longer under normal physiologic control. These may be benign (non-cancerous) or malignant (cancerous).
- nephrectomy
surgery to remove the kidney; the most common treatment for kidney cancer.
- nephritis
inflammation of the kidneys.
- nephrology
the medical specialty concerned with diseases of the kidneys.
- nephropathy
diabetic kidney disease.
- nephrotic syndrome
a condition characterized by high levels of protein in the urine, low levels of protein in the blood, tissue swelling, and high cholesterol.
- nerve conduction tests
procedure to determine nerve impulse generation.
- nerve sparing technique
a surgical technique during a radial prostatectomy where one or both of the neurovascular bundles controlling erections are spared.
- neural plasticity
ability of the brain and/or certain parts of the nervous system to change in order to adapt to new conditions, such as an injury.
- neural prostheses
devices that substitute for an injured or diseased part of the nervous system to enhance the function.
- neural stimulation
to activate or energize a nerve through an external source.
- neural tube defect
type of birth defect, such as spina bifida, that results from failure of the spinal cord or brain to develop normally in a fetus.
- neuralgia
pain in distribution of nerve or nerves.
- neuritis
inflammation of a nerve or nerves.
- neurofibromatosis
a group of inherited disorders in which noncancerous tumors grow on several nerves that may include the hearing nerve.
- neurogenic
of nerve origin.
- neurogenic bladder (Also called neuropathic bladder.)
a bladder disorder that can be caused by a tumor or other condition of the nervous system.
- neurogenic communication disorder
inability to exchange information with others because of hearing, speech, and/or language problems caused by impairment of the nervous system.
- neurological
pertaining to the nervous system.
- neuron
a cell specialized to conduct and generate electrical impulses and to carry information from one part of the brain to another.
- neuropathology
the pathology of the nervous system.
- neuropathy
diabetic nerve damage.
- neurosonography
a procedure that uses ultra high-frequency sound waves that enable the physician to analyze blood flow in cases of possible stroke.
- neurotransmitters
chemical substances that carry impulses from one nerve cell to another; found in the space (synapse) that separates the transmitting neuron's terminal (axon) from the receiving neuron's terminal (dendrite).
- nigral
of or referring to the substantia nigra.
- nitroglycerin
a medication used to relax or dilate arteries.
- nodule (Also called papule.)
a solid, raised bump.
- noise-induced hearing loss
hearing loss that is caused either by a one-time or repeated exposure to very loud sound(s) or sounds at various loudness levels over an extended period of time.
- non-Hodgkin's lymphoma
a type of lymphoma, a cancer in the lymphatic system; causes the cells in the lymphatic system to abnormally reproduce, eventually causing tumors to grow. Non-Hodgkin's lymphoma cells can also spread to other organs.
- non-insulin-dependent diabetes
a condition in which the body either makes too little insulin or cannot properly use the insulin it makes to convert blood glucose to energy. Type 2 diabetes may be controlled with diet, exercise, and weight loss, or may require oral medications and/or insulin injections.
- noninvasive procedures
a diagnostic effort or treatment that does not require entering the body or puncturing the skin.
- nonsteroidal anti-inflammatory drugs (NSAIDs)
medication that produces fever reducing, analgesic (pain relieving), and anti-inflammatory effects.
- nonsyndromic hereditary hearing impairment
hearing loss or deafness that is inherited and is not associated with other inherited clinical characteristics.
- nonulcer dyspepsia
constant pain or discomfort in the upper GI tract.
- norepinephrine
a neurotransmitter found mainly in areas of the brain that are involved in governing autonomic nervous system activity, especially blood pressure and heart rate.
- NSAID
abbreviation for nonsteroidal anti-inflammatory drug, which do not contain corticosteroids and are used to reduce pain and inflammation; aspirin and ibuprofen are two types of NSAIDs.
- nuclear medicine
a specialized area of radiology that uses very small amounts of radioactive substances to examine organ function and structure.
- Nutcracker syndrome
abnormal muscle tightening in the esophagus.
- nutrients
proteins, carbohydrates, fats, vitamins, and minerals provided by food and necessary for growth and the maintenance of life.
