• Specialty
  • Cardiology
  • Dentistry
  • Dermatology
  • General Medicine
  • GI/GU
  • Hematology
  • Immunology
  • Lab Medicine & Pathology
  • Neuro-Psych
  • OB-Gyn
  • Oncology
  • Ophthalmology
  • Orthopaedic
  • Otolaryngology - ENT
  • Radiology
  • Surgery

• General Medicine
  • Diabetes Related Terms
  • Epidemiology Terms
  • General Medicine Terms
  • Sample Reports - General Medicine
  • Sample Reports - Allergy / Immunology
  • Sample Reports - Endocrinology

• General Medicine Terms

- N -

• Narcolepsy

A sudden, uncontrollable disposition to sleep occurring at irregular intervals, with or without obvious predisposing or exciting cause.



• National Cancer Institute

The US government agency for cancer research and information.



• Natural Killer Cell (NK)

A lymphocyte which, unlike other lymphocytes, does not require specific activation by foreign antigen. They are considered to play a 'front line' role in controlling infection, curbing infection until a specific, coordinated immune response can be mounted.



• 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.



• 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

Biopsy procedure in which a small sample of tissue is removed through a hollow needle.



• Neoadjuvant therapy

Chemotherapy given before surgery or radiation therapy.



• Nephrectomy

Surgical removal of the kidney.



• Nephropathy

Diabetic kidney disease.



• Nerve conduction test

Procedure to determine nerve impulse generation.



• Nerve sparing technique

A surgical technique often used during a radial prostatectomy in which one or both of the neurovascular bundles controlling erections are spared.



• Neural mobilization

Techniques by which neural tissues are moved, either by movement relative to their surroundings or by tension development.



• 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

A painful condition caused by disorders of the nervous system.



• Neurasthenia

Nervous exhaustion. A functional neurosis marked by intense nervous irritability and weakness.



• Neuritis

Inflammation of a nerve or nerves.



• Neurogenic

Of nerve origin.



• Neurogenic communication disorder

Inability to exchange information with others because of hearing, speech, and/or language problems caused by impairment of the nervous system.



• Neuromyasthenia

Muscular weakness, usually of emotional origin.



• Neuron

A cell specialized to conduct and generate electrical impulses and to carry information from one part of the brain to another.



• Neuropathology

The study of the nervous system.



• Neuropsychiatric

Relating to organic and functional diseases of the nervous system.



• Neurotransmitters

Substances produced in neurons that promote or inhibit the conduction of nerve impulses, such as epinephrine, norepinephrine, dopamine, serotonin, and gamma-aminobutyrate.



• 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).



• Newborn screening

Examining blood samples from a newborn infant to detect disease-related abnormalities or deficiencies in gene products. There are other purposes for , and methods of, screening newborns.



• NIH

National Institutes of Health.



• Nissen fundoplication

Operation to sew the top of the stomach (fundus) around the esophagus; used to stop stomach contents from flowing back into the esophagus (reflux) and to repair a hiatal hernia.



• Nitrogenous base

A nitrogen containing molecule having the chemical properties of a base.



• Noise-induced hearing loss

Hearing loss that is caused either by a one-time or repeated exposure to very loud sound(s).



• Non-insulin-dependent diabetes

See type 2 diabetes.



• Noninvasive procedures

A diagnostic effort or treatment that does not require entering the body or puncturing the skin.



• Nonsense mutation

A mutation in which a codon is changed to a stop codon, resulting in a truncated protein product.



• Non-steroidal anti-inflammatory drugs (NSAIDS)

Medications that produces antipyretic, analgesic, and anti-inflammatory effects.



• Nonsyndromic hereditary hearing impairment

Hearing loss or deafness that is inherited and is not associated with other inherited clinical characteristics.



• Nontropical sprue

See celiac disease.



• Nonulcer dyspepsia

Constant pain or discomfort in the upper gastrointestinal 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.



• Norwalk virus

Virus that may cause gastrointestinal (GI) infection and diarrhea. (See also gastroenteritis.)



• Nuclear medicine

A specialized area of radiology that uses very small amounts of radioactive substances to examine organ function and structure.



• Nucleic acid

A large molecule composed of nucleotide subunits.



• Nucleotide

A subunit of DNA or RNA, consisting of one chemical base plus a phosphate molecule and a sugar molecule.



• Nucleus

The cell structure that houses the chromosomes.



• Nutrients

Proteins, carbohydrates, fats, vitamins, and minerals provided by food and necessary for growth and the maintenance of life.