chorioallantoic membraneThe membrane in hens' eggs that helps chicken embryos get enough oxygen and calcium for development. The calcium comes from the egg shell.
chorioblastoma(KOR-ee-oh-blas-TOH-muh) A malignant, fast-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and help…
choriocarcinoma(KOR-ee-oh-KAR-sih-NOH-muh) A malignant, fast-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and…
chorioepithelioma(KOR-ee-oh-EH-pih-THEE-lee-OH-muh) A malignant, fast-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus…
ChorionThe multilayered, outermost fetal membrane. As pregnancy progresses, part of the chorion becomes the placenta.
chorionic carcinoma(KOR-ee-AH-nik KAR-sih-NOH-muh) A malignant, fast-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and…
choroid(KOR-oid) A thin layer of tissue that is part of the middle layer of the wall of the eye, between the sclera (white outer layer of the eye) and the retina…
choroid plexus tumor(KOR-oyd PLEK-sus TOO-mer) A rare type of cancer that occurs in the ventricles of the brain. It usually occurs in children younger than 2 years.
chosen-plaintext attackIn cryptography, an analytical attack in which a cryptanalyst can submit an unlimited number of plaintext messages and examine the corresponding…
CHPPA procedure that bathes the abdominal cavity in fluid that contains anticancer drugs. This fluid is warmer than body temperature.
chroma keyingIn television, nearly instantaneous switching between multiple video signals, based on the state, i.e.
chroma noiseNoise that manifests itself in a video picture as colored snow. [After Silicon]
chromaffin cell(KROH-muh-fin ...) A type of cell that makes neurohormones (chemicals that are made by nerve cells and used to send signals to other cells) and releases…
chromatic dispersionA commonly used (but redundant) synonym for material dispersion. See dispersion.
chromaticity diagramA two-dimensional Cartesian plot that depicts the multidimensional subjective relationship among colors perceived by the normal human visual system (eyes…
ChromatidEach of the two daughter strands of a duplicated chromosome joined at the centromere during mitosis and meiosis.
chromatinSubstance of which eukaryotic chromosomes are composed. It consists of a complex of DNA, histone and non-histone chromosomal proteins (mainly histones)…
chromatin fibreThe standard structural conformation of chromatin in strands of 30 nm average diameter.
Chromatogramthe pattern of separated substances obtained by chromatography.
Chromatographya method for separating mixtures based on differences in the speed at which they migrate over or through a stationary phase.
chrominanceThe difference between a color and a specified reference color having a specified chromaticity and an equal luminance. [After Laurin]
chrominance signalIn color television, that signal or portion of the composite signal that bears the color information.
chromium(KROH-mee-yum): A kind of metal that comes in different forms and is found in rocks and soil. Some forms are also produced during industrial processes.
chromocentreBody produced by fusion of the heterochromatic regions of the chromosomes in the polytene tissues (e.g. the salivary glands) of certain Diptera.
ChromomereOne of the serially aligned beads or granules of a eukaryotic chromosome, resulting from local coiling of a continuous DNA thread.
chromomeresSmall dense bodies identified by their characteristic size and linear arrangement along a chromosome.
chromonema(pl.: chromonemata) An optically single thread forming an axial structure within each chromosome.
chromoplastPlastid containing pigments other than chlorophyll. See: chloroplast.
chromosomal aberrationAn abnormal change in chromosome structure or number, including deficiency, duplication, inversion, translocation, aneuploidy, polyploidy, or any other…
chromosomal integration siteA chromosomal location where foreign DNA can be integrated, often without impairing any essential function in the host organism.
Chromosomal inversionChromosome segments that have been turned 180 degrees. The gene sequence for the segment is reversed with respect to the rest of the chromosome.
chromosomal polymorphismThe occurrence of one to several chromosomes in two or more alteRNA tive structural forms within a population; the structurally changed chromosomes are…
Chromosome(KROH-muh-some) Part of a cell that contains genetic information. Except for sperm and eggs, all human cells contain 46 chromosomes.
chromosome bandingDifferential staining of chromosomes in such a way that light and dark areas occur along the length of the chromosomes in repeatable patterns.
chromosome jumpingA technique that allows two segments of duplex DNA that are separated by thousands of base pairs (about 200 kb) to be cloned together.
chromosome landingAn alteRNA tive to chromosome walking for positional cloning. Clones of genomic DNA are fragmented so as to include both the target gene and a closely…
chromosome mutationA change in the gross structure of a chromosome, usually causing severely deleterious effects in the organism, but can be maintained in a population (See…
Chromosome paintingAttachment of certain fluorescent dyes to targeted parts of the chromosome. Used as a diagnositic for particular diseases, e.g. types of leukemia.
chromosome theory of inheritanceThe theory that chromosomes carry the genetic information and that their behaviour during meiosis provides the physical basis for segregation and…
Chromosome walkingWorking from a flanking DNA marker, overlapping clones are successively identified that span a chromosomal region of interest. (See Chromosome.)
ChromosomesThe self-replicating genetic structure of cells containing the cellular DNA. Humans have 23 pairs of chromosomes.
Chromosphere2,500 km thick (1,600 mi) layer of plasma above the Sun’s photosphere. Temperatures range from ~4500 K to 60,000 K (110,000 to 8,000°F).
Chromospheric EventsIn solar-terrestrial terms, flares that are just Chromospheric Events without Centimetric Bursts or Ionospheric Effects. (SID) (Class C flare)
chronic(KRAH-nik) A disease or condition that persists or progresses over a long period of time.
Chronic ComplicationsAssociated with the duration of the disease, the lack of metabolic control of blood glucose, and other factors which result in tissue damage and have a…
Chronic ConditionA medical condition or disease that goes on for a long period of time. Examples are diabetes and cystic fibrosis.
Chronic Disease ManagementAn integrated care approach to managing illness which includes screenings, check-ups, monitoring and coordinating treatment, and patient education.
Chronic effectsEffects resulting from exposure to low levels of a stressing factor (e.g., contaminant, disease, electromagnetic field, noise, and radionuclides) over…
chronic eosinophilic leukemia(KRAH-nik EE-oh-SIH-noh-FIH-lik loo-KEE-mee-uh) A disease in which too many eosinophils (a type of white blood cell) are found in the bone marrow, blood…
chronic fatigue syndrome(KRAH-nik fuh-TEEG SIN-drome) A condition lasting for more than 6 months in which a person feels tired most of the time and may have trouble concentrating…
chronic granulocytic leukemia(KRAH-nik GRAN-yoo-loh-SIH-tik loo-KEE-mee-uh) A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone…
Chronic HyperglycemiaExcessively high blood glucose that is slow progressing and long continuance of that may result in diabetic ketoacidosis or nonketotic hyperosmolar coma.
chronic idiopathic myelofibrosis(KRAH-nik IH-dee-oh-PA-thik MY-eh-loh-fy-BROH-sis) A progressive, chronic disease in which the bone marrow is replaced by fibrous tissue and blood is made…
chronic leukemia(KRAH-nik loo-KEE-mee-uh) A slowly progressing cancer that starts in blood-forming tissues such as the bone marrow, and causes large numbers of white…
chronic lymphoblastic leukemia(KRAH-nik LIM-foh-BLAS-tik loo-KEE-mee-uh) A slow-growing type of leukemia (blood cancer) in which too many lymphoblasts (immature white blood cells) are…
chronic lymphocytic leukemia(KRAH-nik LIM-foh-SIH-tik loo-KEE-mee-uh) A slow-growing type of leukemia (blood cancer) in which too many lymphoblasts (immature white blood cells) are…
chronic myelogenous leukemia(KRAH-nik MY-eh-LAH-jeh-nus loo-KEE-mee-uh) A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow.
chronic myeloid leukemia(KRAH-nik MY-eh-loyd loo-KEE-mee-uh) A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow.
chronic myelomonocytic leukemia(KRAH-nik MY-eh-loh-MAH-noh-SIH-tik loo-KEE-mee-uh) A slowly progressing type of myelodysplastic/myeloproliferative disease in which too many…
chronic neutrophilic leukemia(KRAH-nik NOO-tro-FIH-lik loo-KEE-mee-uh) A disease in which too many neutrophils (a type of white blood cell) are found in the blood.
chronic obstructive pulmonary disease(KRAH-nik ob-STRUK-tiv PUL-muh-NAYR-ee dih-ZEEZ) A type of lung disease marked by permanent damage to tissues in the lungs, making it hard to breathe.
chronic pain(KRAH-nik payn) Pain that can range from mild to severe, and persists or progresses over a long period of time.
chronic phase(KRAH-nik fayz) Refers to the early stages of chronic myelogenous leukemia or chronic lymphocytic leukemia.
chronic phase chronic myelogenous leukemia(KRAH-nik FAYZ KRAH-nik MY-eh-LAH-jeh-nus loo-KEE-mee-uh) A phase of chronic myelogenous leukemia in which fewer than 10% of the cells in the blood and…
Chronic TrunkTrunk: A trunk experiencing a much higher then normal rate of failure or switching irregularities, over a period of time, with resulting high incidence of…
ChronologicalArranged in the order in which events happened; according to date, from the first event to the last event.
chronological fileRecords filed in date sequence Also referred to as CHRON and chron file.
chronologya general term for the age-depth relationship in ice, sediment, or another deposit.
CHS 828A drug that is being studied in the treatment of solid tumors.
cHTML (Compact HTML)Compact HTML (cHTML) is a subset of HTML which is designed for small devices. The major features of HTML that are excluded from cHTML are: JPEG image…
chuggerTopwater plug with a dished-out, concave or cupped head designed to make a splash when pulled sharply.
chumTo throw chum (typically cut up pieces of bait fish or other bait) overboard to attract fish.
ChurningExcessive buying and selling in a customer's account undertaken to generate commissions for the broker.
chymosinAn enzyme that clots milk, used in the manufacture of cheese.
CICirrus clouds- High-level clouds (16,000 feet or higher), composed of ice crystals and appearing in the form of white, delicate filaments or white or…
CI (n)Capability Increment (Number), e.g., CI-2, (NMD BMC3 term).
CI-1033A substance being studied in the treatment of some types of cancer. CI-1033 blocks the action of proteins called epidermal growth factor receptors, and…
CI-958A substance being studied in the treatment of some types of cancer. CI-958 binds to DNA and stops cells, including cancer cells, from repairing damage to…
CI-980An anticancer drug that belongs to the family of drugs called mitotic inhibitors. Also called mivobulin isethionate.
CI-994A substance being studied in the treatment of non-small cell lung cancer. Also called N-acetyldinaline.
CIDR (Classless Interdomain Routing)An IP address and routing management method that allocates IP addresses in a way that reduces the number of routes stored on any individual router, while…
CIDS(1) Control, Instrumentation and Diagnostic Systems (2) Critical Item Development Specification.
CIDSEConsolidated Integrated Development support Environment.
CIEAbbreviation for Commission International de l'Eclairage (International Commission on Illumination).