neurotransmitter(NOOR-oh-tranz-MIH-ter) A chemical that is made by nerve cells and used to communicate with other cells, including other nerve cells and muscle cells.
neurotropismAn ability to invade and live in neural tissue. This term is usually used to describe the ability of viruses to infect nerve tissue.
neutropenia(noo-troh-PEE-nee-uh) An abnormal decrease in the number of neutrophils, a type of white blood cell.
neutrophil(NOO-tro-fil) A type of white blood cell.
nevoid basal cell carcinoma syndrome(NEE-voyd BAY-sul SEL KAR-sih-NOH-muh SIN-drome) A genetic condition that causes unusual facial features and disorders of the skin, bones, nervous system…
nevus(NEE-vus) A benign (noncancerous) growth on the skin that is formed by a cluster of melanocytes (cells that make a substance called melanin, which gives…
Newcastle disease virus(NOO-ka-sul dih-ZEEZ VY-rus) A bird virus that is being studied in the treatment of cancer.
Nexavar(NEK-suh-var) A drug used to treat advanced kidney cancer and a type of liver cancer that cannot be removed by surgery.
Nexium(NEK-see-um) A drug that blocks acid from being made in the stomach. It is used to treat acid reflux disease and to prevent certain types of…
NF1A rare genetic condition that causes brown spots and tumors on the skin, freckling in skin areas not exposed to the sun, tumors on the nerves, and…
NF2A genetic condition in which tumors form on the nerves of the inner ear and cause loss of hearing and balance.
NG-monomethyl-L-arginineAn amino acid derivative used to counteract high blood pressure caused by interleukin-2.
NGR-TNFA substance being studied in the treatment of cancer. It is made by linking tumor necrosis factor (TNF) to a peptide.
NHLAny of a large group of cancers of the immune system. NHLs can occur at any age and are often marked by enlarged lymph nodes, fever, and weight loss.
niacinamideA vitamin being studied to increase the effect of radiation therapy on tumor cells. Also called nicotinamide.
Nickel(NIK-ul): A kind of metal found in soil and often used in alloys and in industry.
nicotinamideA vitamin being studied to increase the effect of radiation therapy on tumor cells.
nicotine(NIH-kuh-TEEN) An addictive, poisonous chemical found in tobacco. It can also be made in the laboratory.
nicotine gum(NIH-kuh-TEENâ¦) A chewing gum that contains a small dose of nicotine, which enters the blood by being absorbed through the lining of the mouth.
nicotine inhaler(NIH-kuh-TEEN in-HAY-ler) A device used to inhale (breathe in) small doses of nicotine through the mouth.
nicotine lozenge(NIH-kuh-TEEN LAH-zinj) A hard candy-like tablet that contains a small dose of nicotine.
nicotine nasal spray(NIH-kuh-TEEN NAY-zulâ¦) A nose spray that contains a small dose of nicotine, which enters the blood by being absorbed through the lining of the…
nicotine patch(NIH-kuh-TEEN...) A patch that sticks on the skin and contains a small dose of nicotine, which enters the blood by being absorbed through the skin.
nicotine replacement therapy(NIH-kuh-TEEN rih-PLAYS-munt THAYR-uh-pee) A type of treatment that uses special products to give small, steady doses of nicotine to help stop cravings…
NIHA federal agency in the U.S. that conducts biomedical research in its own laboratories; supports the research of non-Federal scientists in universities…
nilotinib(ny-LOH-tih-nib) A drug used to treat certain types of chronic myelogenous leukemia (CML).
nilutamide(ny-LOO-tuh-mide) A drug that blocks the effects of male hormones in the body. It is a type of antiandrogen.
nimodipineBelongs to a family of drugs called calcium channel blockers. It is being investigated for use with anticancer drugs to prevent or overcome drug…
nimotuzumab(ny-moh-TOO-zoo-mab) A monoclonal antibody being studied in the treatment of some types of cancer.
nimustine(NY-mus-tine) A substance that is being studied in the treatment of brain cancer. It belongs to the family of drugs called nitrosoureas.
Nipent(NY-pent) The active ingredient in a drug that is used to treat hairy cell leukemia and is being studied in the treatment of other types of cancer.
NippleIn anatomy, the small raised area in the center of the breast through which milk can flow to the outside.
nitrocamptothecinAn alkaloid drug belonging to a class of anticancer agents called topoisomerase inhibitors.
nitrosourea(nye-TRO-so-yoo-REE-ah) An anticancer drug that can cross the blood-brain barrier. Carmustine and lomustine are nitrosoureas.
NK cellA type of white blood cell that contains granules with enzymes that can kill tumor cells or microbial cells.
NLPHLA rare type of Hodgkin lymphoma, which is a cancer of the immune system. It is marked by the presence of a type of cell called a popcorn cell, which is…
NMRIA procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the body.
NMSA life-threatening condition that may be caused by certain drugs used to treat mental illness, nausea, or vomiting.
node-negativeCancer that has not spread to the lymph nodes.
node-positive(... PAH-zih-tiv) Cancer that has spread to the lymph nodes.
nodular parenchyma(NAH-juh-ler puh-REN-kih-muh) A small mass of tissue within a gland or organ that carries out the specialized functions of the gland or organ.
nodule(NOD-yool) A growth or lump that may be cancerous or noncancerous.
nolatrexedA substance that is being studied in the treatment of liver cancer. It belongs to the family of drugs called thymidylate synthase inhibitors.
Nolvadex(NOL-vuh-dex) A drug used to treat certain types of breast cancer in women and men.
nomogram(NAH-moh-GRAM) A mathematical device or model that shows relationships between things.
non-Hodgkin lymphoma(non-HOJ-kin lim-FOH-muh) Any of a large group of cancers of the immune system.
non-melanoma skin cancerSkin cancer begins in the outer layer of the skin. Melanoma is a cancer that begins in skin cells that produce melanin, which gives your skin color.
non-small cell lung cancerA group of lung cancers that are named for the kinds of cells found in the cancer and how the cells look under a microscope.
nonblindedDescribes a clinical trial or other experiment in which the researchers know what treatments are being given to each study subject or experimental group.
nonconsecutive case seriesA clinical study that includes some, but not all, of the eligible patients identified by the researchers during the study registration period.
noncontiguous lymphoma(non-kun-TIG-yoo-us lim-FOH-muh) Lymphoma in which the lymph nodes containing cancer are not next to each other, but are on the same side of the diaphragm…
nonfunctioning tumor(non-FUNK-shuh-ning TOO-mer) A tumor that is found in endocrine tissue but that does not make extra hormones (chemicals that travel in the blood and…
nonhematologic cancer(non-HEE-muh-tuh-LAH-jik KAN-ser) Cancer that does not begin in the blood or bone marrow.
noniMorinda citrifolia. A tropical shrub. An extract from the fruit is being studied as a treatment for cancer, and extracts from the fruit, leaves, or roots…
noninvasive(NON-in-VAY-siv) In medicine, it describes a procedure that does not require inserting an instrument through the skin or into a body opening.
nonlyticIn biology, refers to viruses that do not kill infected cells by disrupting their plasma membranes.
nonmalignant hematologic disorder(non-muh-LIG-nunt HEE-muh-tuh-LAH-jik dis-OR-der) A disorder of the blood. Some nonmalignant hematologic disorders may lead to leukemia.
nonmelanoma carcinoma in situ(non-MEH-luh-NOH-muh KAR-sih-NOH-muh in SY-too) Abnormal cells are found in the squamous cell or basal cell layer of the epidermis (outer layer of skin).
nonmelanoma skin cancer(... non-MEH-luh-NOH-muh skin KAN-ser) Skin cancer that forms in basal cells or squamous cells but not in melanocytes (pigment-producing cells of the…
nonmelanomatousHaving to do with skin cancer that develops in basal cells or squamous cells but not in melanocytes (pigment-producing cells of the skin).
nonmetastatic(non-meh-tuh-STA-tik) Cancer that has not spread from the primary (original) site to other sites in the body.
nonopioidA drug that is not an opioid. Examples include acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDS), such as aspirin and ibuprofen.
nonprescriptionA medicine that can be bought without a prescription (doctor's order). Examples include analgesics (pain relievers) such as aspirin and acetaminophen.
nonrandomized clinical trialA clinical trial in which the participants are not assigned by chance to different treatment groups.
nonseminoma(non-sem-ih-NO-ma) A group of testicular cancers that begin in the germ cells (cells that give rise to sperm).
nonspecific immune cell(non-speh-SIH-fik ih-MYOON SEL) A cell (such as a phagocyte or a macrophage) that responds to many antigens, not just one antigen.
nonsteroidal anti-inflammatory drug(NON-steh-ROY-dul AN-tee-in-FLA-muh-TOR-ee ...) A drug that decreases fever, swelling, pain, and redness. Also called NSAID.
nonsteroidal aromatase inhibitor(NON-steh-ROY-dul uh-ROH-muh-tayz in-HIH-bih-ter) A drug that decreases the production of sex hormones (estrogen or testosterone) and slows the growth of…
noradrenaline(NOR-uh-dreh-nuh-lin) A chemical made by some nerve cells and in the adrenal gland.
nordihydroguaiaretic acid(NOR-dy-HY-droh-GWY-uh-reh-tik A-sid) A drug put on the skin to treat growths caused by sun exposure.
Norepinephrine(NOR-ep-ih-NEF-rin) A chemical made by some nerve cells and in the adrenal gland.
Notary PublicA person who serves as a public official and certifies the authenticity of required signatures on a document by signing and stamping the document.
NovantroneA drug used to treat advanced prostate cancer that does not respond to hormones, adult acute nonlymphocytic leukemia, and advanced or chronic multiple…
novobiocinAn antibiotic drug used to treat infection.
Nplate(EN-playt) A drug used to treat patients with immune thrombocytopenic purpura (ITP) who do not get better with other forms of treatment.
NSAIDA drug that decreases fever, swelling, pain, and redness. Also called nonsteroidal anti-inflammatory drug.
NSC 655649A substance that is being studied in the treatment of cancer. It belongs to the families of drugs called antitumor antibiotics and topoisomerase…
nuclear gradeAn evaluation of the size and shape of the nucleus in tumor cells and the percentage of tumor cells that are in the process of dividing or growing.
nuclear magnetic resonance imaging(NOO-klee-er mag-NEH-tik REH-zuh-nunts IH-muh-jing) A procedure in which radio waves and a powerful magnet linked to a computer are used to create…
nuclear medicine scan(NOO-klee-er MEH-dih-sin SKAN) A method of diagnostic imaging that uses very small amounts of radioactive material.
Nucleotide(NOO-klee-oh-TIDE) A building block for nucleic acids (the molecules inside cells that carry genetic information).
Nucleus(NOO-klee-us) In biology, the structure in a cell that contains the chromosomes.
nurseA health professional trained to care for people who are ill or disabled.
Nursing HomeA place that gives care to people who have physical or mental disabilities and need help with activities of daily living (such as taking a bath, getting…
nutraceuticalA food or dietary supplement that is believed to provide health benefits.
nutrient(NOO-tree-ent) A chemical compound (such as protein, fat, carbohydrate, vitamin, or mineral) contained in foods.
nutrition(noo-TRIH-shun) The taking in and use of food and other nourishing material by the body. Nutrition is a 3-part process. First, food or drink is consumed.
nutrition therapy(noo-TRIH-shun THAYR-uh-pee) Treatment based on nutrition. It includes checking a person's nutrition status, and giving the right foods or nutrients to…
nutritional counseling(noo-TRIH-shuh-nul KOWN-suh-ling) A process by which a health professional with special training in nutrition helps people make healthy food choices and…
nutritional status(noo-TRIH-shuh-nul STA-tus) The state of a person's health in terms of the nutrients in his or her diet.
nutritional supplement(noo-TRIH-shuh-nul SUH-pleh-ment) A product that is added to the diet. A nutritional supplement is taken by mouth, and usually contains one or more…
nutritionistA health professional with special training in nutrition who can help with dietary choices. Also called dietitian.