Rarely used term relating to the mental processes. [G. noema, perception, a thought]
Cognition, especially through direct and self-evident knowledge. [G. n., thought, intelligence]
A circumscript region in the lower part of the medulla oblongata, near the apex of the calamus scriptorius, interpreted by M. Flourens (1858) as a nerve center controlling ...
A genus of aerobic to facultatively anaerobic, motile, peritrichous bacteria (family Brucellaceae) containing small, slender, Gram-negative, encapsulated rods. These organisms ...
1. Unwanted sound, particularly complex sound that lacks a musical quality because the various frequencies of which it is composed are not whole or partial number multiples ...
Offensive to the senses and especially disgusting, offensive, or harmful to the sense of smell. For example, the smell of a chemical such as formaldehyde can be noisome. ...
An antiestrogen (a drug that blocks the effects of estrogen) which competes with estrogen for binding sites in target tissues such as breast. Tamoxifen has been widely ...
A gangrenous stomatitis, usually beginning in the mucous membrane of the corner of the mouth or cheek, and then progressing fairly rapidly to involve the entire thickness of ...
Georges, 20th century French optical inventor. See N. optics.
A system of names as of anatomic structures, organisms, used in any science. [L. nomenclatura, a listing of names, fr. nomen, name, + calo, to proclaim]
- binary n., binomial ...
Committee on Nomenclature of the German Anatomical Society, appointed to revise or supplement the BNA (1895).
The modification of the Basle N. or BNA system of anatomic terminology adopted in 1955 by the International Congress of Anatomists in Paris, France. The International Anatomical ...
A form of line chart showing scales for the variables involved in a particular formula in such a way that corresponding values for each variable lie in a straight line ...
1. A graph consisting of three coplanar curves, usually parallel, each graduated for a different variable so that a straight line cutting all three curves intersects the related ...
Denoting the generalizations pertaining to the behavior of groups of individuals as groups, as opposed to idiographic. [G. nomos, law, + thesis, a placing]
Relating to, or occurring at, the usual or normal place. [G. nomos, law, custom, + topos, place]
non compos mentis
Not of sound mind; mentally incapable of managing one's affairs. [L. non, not, + compos, participating, competent, + mens, gen. mentis, mind]
Non-rapid eye movement sleep
NREM (non-rapid eye movement) sleep is dreamless sleep. During NREM, the brain waves on the electroencephalographic (EEG) recording are typically slow and of high voltage, the ...
Used of genes that are not competitors at the same locus; how independently they will behave depends on whether their loci are linked. At least when first formed (for instance, as ...
Occurring on the ninth day. [L. nonus, ninth]
An oligopeptide containing nine amino acid residues ( E.G., oxytocin).
Inflammation of the prostate not due to bacterial infection. The prostate is a walnut-sized organ below the male bladder that surrounds the urethra and contributes fluid to the ...
Denoting a nontaxonomic division of Nematoda embracing those in which the male copulatory bursa is only a skin fold containing no fleshy ribs, as seen in hookworms and other ...
1. Lacking cellular organization, as applied to viruses, which can only replicate within a cell, whether prokaryotic or eukaryotic. SYN: subcellular. 2. SYN: acellular (1).
The strand of DNA that does not carry the information necessary to make proteins. DNA normally has two strands — the coding strand and the non-coding strand. Although these ...
The failure or refusal to comply: the failure or refusal to conform and adapt one's actions to a rule or to necessity. The term "noncompliance" is used in medicine particularly in ...
Absence of disease when a specific disease is suspected but not found.
Failure of paired chromosomes to disjoin (separate) during cell division so that both chromosomes go to one daughter cell and none to the other. Nondisjunction causes errors in ...
A substance with molecules that do not, in solution, dissociate to ions and, therefore, do not carry an electric current.
1. Not causing estrus in animals. 2. Not having an action similar to that of an estrogen. Cf.:nonuterotropic. SYN: nonoestrogenic.
Pertaining to an individual that is not immune or to a serum from such an individual.
Denoting a procedure that does not require insertion of an instrument or device through the skin or a body orifice for diagnosis or treatment.
A class of radiographic contrast media that do not ionize in solution, thereby decreasing effective osmolarity and toxicity. SEE ALSO: low osmolar contrast agent.
Nonlymphocytic leukemia, acute
Abbreviated ANLL. More commonly called acute myeloid leukemia (AML). A quickly progressive malignant disease in which there are too many immature blood-forming cells in the ...
The ethical principle of doing no harm, based on the Hippocratic maxim, primum non nocere, first do no harm. [non- + L. maleficencia, evildoing, fr. male, badly, wrongly, + ...
Failure of a tooth to contact an opposing tooth.
A sugar with nine carbon atoms. [L. nonus, ninth]
Nonoxynol-9 is the most commonly encountered spermatocide in the United States. As with other spermatocides, it destroys spermatozoa; it kills sperm. The nonoxynols, technically ...
A group of compounds that are surface-acting agents, used in spermicidal preparations such as contraceptive foam and diaphragm jelly.
A group of statistical maneuvers that can be applied effectively to data nonnormal or non-Gaussian in distribution.
Incapable of causing disease. Nonpathogenic bacteria are harmless. By contrast, pathogenic bacteria can cause disease. For example, nonpathogenic E. coli are E. coli that are ...
The state in which a genetic trait, although present in the appropriate genotype ( i.e., homozygous, hemizygous, or heterozygous according to the state of dominance and mode ...
A genetic trait (characteristic) that is present in the genome but does not manifest itself in the individual. By contrast, a penetrant trait is one that manifests itself. If, ...
A short name (often called a generic name) of a chemical, drug, or other substance that is not subject to trademark (proprietary) rights but is, in contrast to a trivial name, ...
Not by chance alone. Not in keeping with the process by which an outcome is determined solely by chance, for example, by a coin flip. The opposite of nonrandom is random.
nonreset nodus sinuatrialis
Nonreset of the sinoatrial node produced by a premature atrial depolarizaton when the sum of the duration of the premature cycle and the return cycle is fully compensatory, ...
Failure of normal rotation.
- n. of intestine a developmental anomaly resulting in the small intestine being on the right of the abdomen and the colon on the left.
- n. of kidney ...
Not subject to saponification; E.G., triacylglycerols are saponifiable but cholesterol is n..
An individual whose saliva does not contain antigens of the ABO blood group. SEE ALSO: secretor.
: A classification of testicular cancers that arise in specialized sex cells called germ cells. Nonseminomas include embryonal carcinoma, teratoma, choriocarcinoma, and yolk ...
As used in genetics, relating to a mutation that causes a sequence such that the growing peptide chain terminates, often after several incorrect amino acid residues are ...
A set of three adjacent bases in the DNA or their complementary bases in messenger RNA that specifies the premature end of a polypeptide chain. The three nonsense codons in ...
A mutation (a change) in a base in the DNA that prematurely stops the translation (reading) of messenger RNA (mRNA) resulting in a polypeptide chain that ends prematurely and a ...
A structurally normal spine that appears to have a lateral curve (scoliosis). Nonstructural scoliosis involves a temporary change of spinal curvature. This is caused by an ...
Failure of normal healing of a fractured bone.
Not causing an effect on the uterus. Cf.:nonestrogenic.
Having no valency; not capable of entering into chemical composition.
Denoting communication without words, e.g., by signs, symbols, facial expressions, gestures, posture.
1. Incapable of independent existence; often denoting a prematurely born fetus. 2. Denoting a microorganism or parasite incapable of metabolic or reproductive activity.
Jacqueline A., U.S. pediatric cardiologist, *1921. See N. syndrome.
Noonan syndrome (NS)
A multifaceted genetic disorder characterized by a series of birth defects (congenital malformations) including dysmorphic (malformed) facial features, short stature after birth ...
1. Chemical prefix denoting 1) elimination of one methylene group from a chain, the highest permissible locant being used; 2) contraction of a (steroid) ring by one CH2 unit, ...
- n. acid tartrate SYN: norepinephrine bitartrate.
- n. bitartrate SYN: norepinephrine bitartrate.
An active sedative/hypnotic of the benzodiazepine class; an active metabolite of diazepam, chlorazepate, and several other benzodiazepines; has a long biologic half-life ...
l-(−)-α-(aminomethyl)-3,4-dihydroxybenzyl alcohol; a catecholamine hormone of which the natural form is d, although the l form has some activity; the base is considered to be ...
An androgenic steroid similar chemically and pharmacologically to testosterone.
A potent orally effective progestational agent with some estrogenic and androgenic activity; used as a substitute for progesterone and, in combination with an estrogen, as an ...
An orally active progestin with some estrogenic activity; used as a progestational agent and, in combination with mestranol, as an oral contraceptive.
An oral broad-spectrum quinoline antibacterial agent used in the treatment of urinary tract infections.
A progestin used in oral contraceptive products.
α-Amino-n-caproic acid; 2-aminohexanoic acid; an α-amino acid, isomer of leucine and isoleucine, but not found in proteins; a deamination product of l-lysine, to which it is ...
1. The usual value. 2. The desirable value or behavior.
1. SYN: aspect. 2. SYN: profile (1). 3. SYN: projection. [L. a carpenter's square]
- n. anterior SYN: facial aspect.
- n. basilaris SYN: external surface of cranial base.
1. Typical; usual; according to the rule or standard. 2. In bacteriology, nonimmune; untreated; denoting an animal, or the serum or substance contained therein, that has not ...
Normal pressure hydrocephalus (NPH)
Hydrocephalus is an abnormal buildup of cerebrospinal fluid (CSF) in the brain. The fluid (the CSF) is often under increased pressure which can compress and damage the brain. ...
By convention, the normal range for whatever (a particular test, condition, symptom, behavior, etc.) is set to cover ninety-five percent (95%) of all values from the general ...
1. Making normal or according to the standard. 2. Reducing or strengthening of a solution to make it normal. 3. Adjusting one curve to another by multiplication of the points of ...
A metabolite of meperidine in which the N-methyl group has been removed. The compound possesses convulsant properties.
A catabolite of norepinephrine found, together with metanephrine, in the urine and some tissues, resulting from the action of catechol-O-methyltransferase on norepinephrine; ...
Normal, usual. [L. normalis, according to pattern]
Denoting a barometric pressure equivalent to sea level pressure. [ normo- + G. baros, weight]
A nucleated red blood cell, the immediate precursor of a normal erythrocyte in humans. Its four stages of development are: 1) pronormoblast, 2) basophilic n., 3) polychromatic ...
Excessive production of normoblasts by the bone marrow.
A state in which the arterial carbon dioxide pressure is normal, about 40 mm Hg. SEE ALSO: eucapnia. [ normo- + G. kapnos, vapor]
Normal color; referring to blood in which the amount of hemoglobin in the red blood cells is normal. [ normo- + G. chroma, color]
Being normal in color; referring especially to red blood cells that possess the normal quantity of hemoglobin.
A nonnucleated erythrocyte of normal size (average 7.5 μm); a normal, healthy red blood cell. SYN: normoerythrocyte. [ normo- + G. kytos, cell]
A normal state of the blood with regard to its component formed elements.
Condition in which specific gravity of urine is normal. [ normo- + G. sthenos, strength, + ouron, urine]
Indicating a normal arterial blood pressure. SYN: normotonic (2).
Environmental temperature that does not cause increased or depressed activity of body cells. [ normo- + G. therme, heat]
1. Relating to or characterized by normal muscular tone. SYN: eutonic. 2. SYN: normotensive.
The state of being in the normal place; used in reference to normal placement of an organ. [ normo- + G. topos, place]
Relating to normotopia; in the right place.
A normal blood volume. [ normo- + volume, + G. haima, blood]
A state in which the partial pressure of oxygen in the inspired gas is equal to that of air at sea level, about 150 mm Hg. [ normo- + oxygen]
A tripeptide analog of glutathione (l-cysteine replaced by l-alanine), found in the lens of the eye.
Implantable progestin in the form of Norplant was approved by the U.S. Food and Drug Administration (FDA) for contraception in 1990 and the newer Norplant 2 was approved in ...
Gordon, Danish ophthalmologist, 1855–1941. See N. disease.
Richard, English physiologist, 1830–1916. See N. corpuscles, under corpuscle.
Steroids in which an angular methyl group is missing; most commonly, the group between the A and B rings (C-19).
North Asian tick-borne rickettsiosis
One of the tick-borne rickettsial diseases of the eastern hemisphere, similar to Rocky Mountain spotted fever, but less severe, with fever, a small ulcer (eschar) at the site of ...
A technique in molecular biology, used mainly to separate and identify pieces of RNA. Called a Northern blot only because it is similar to a Southern blot (which is named after ...
U.F., U.S. obstetrician. See N. operation.
Larry, 20th century U.S. oncologist. See N.-Simon hypothesis.
α-Aminovaleric acid; the straight chain analog of valine; not found in proteins.
: A family of small round viruses that are an important cause of viral gastroenteritis (viral inflammation of the stomach and intestines). Norwalk disease is a significant ...
An extremely common cause of foodborne acute gastroenteritis, usually with more vomiting than diarrhea, that resolves within 2-3 days. Clinical criteria for the diagnosis ...
Prefix indicating a phosphonic acid radical (–PO3H2) attached through an oxygen atom, hence a phosphoric ester. SEE ALSO: phospho-.
The phosphoric ester of serine; found as a constituent in many proteins ( e.g., phosphorylase a and phosvitin).
A reagent used in the identification and the detection of amino acid.
An enzyme catalyzing the reaction between cystathionine and succinate to form l-cysteine and O-succinyl-l-homoserine. SYN: cystathionine γ-synthase.
1. Abbreviation for L. oculus dexter, right eye. 2. Abbreviation for Doctor of Optometry. See optometrist.
Abbreviation for L. omni die, every day.
Abbreviation for L. oculus sinister, left eye.
Abbreviation for Latin oculus uterque, each eye or both eyes.
Abbreviation for occipitoanterior position.
Obsolete term for an ovary. See oo-, oophor-, ovario-. [G. oarion, a small egg, dim. of oon, egg]
A solemn affirmation or attestation.
Oath of Maimonides
A prayer that is said to have been written by the 12th-century physician-philosopher Moses Maimonides. Like the famous oath of Hippocrates, the prayer of Maimonides is often ...
Abbreviation for obstetrician or for obstetrics, the art and science of managing pregnancy, labor and the puerperium, the time immediately after delivery.
* * *
Abbreviation for ...
A commonly used abbreviation. OB is short for obstetrics or for an obstetrician, a physician who delivers babies. GYN is short for gynecology or for a gynecologist, a physician ...
A craniometric point on the sagittal suture between the parietal foramina near the lambdoid suture. [G. obelos, a spit]
Friedrich, Austrian physician, 1861–1925. See O. test.
Otto H.F., German physician, 1843–1873. See O. spirillum.
Heinrich, Austrian neurologist, 1847–1922. See O.- Redlich line, O.- Redlich zone.
Well above ones normal weight. A person has traditionally been considered to be obese if they are more than 20 percent over their ideal weight. That ideal weight must take into ...
The state of being well above ones normal weight. A person has traditionally been considered to be obese if they are more than 20 percent over their ideal weight. That ideal ...
Overweight caused by consuming more food than the person’s activity level
A fat distribution generally characteristic of that of a woman, around the hips, etc. Gynecoid means like a woman, womanly, female. The word gynecoid comes from the Greek gyno, ...
The point on the midline of the dorsal surface of the medulla oblongata that marks the caudal angle of the rhomboid fossa or fourth ventricle. It corresponds to a small, ...
1. A rendering dark or obscure. 2. A deliberate attempt to confuse or to prevent understanding. [L. ob-fusco, pp. -atus, to darken, fr. fuscus, dark, tawny]
1. Anything to which thought or action is directed. 2. In psychoanalysis, that through which an instinct can achieve its aim. 3. In psychoanalysis, often used synonymously ...
In psychoanalysis, the object (usually a person) upon which psychic energy is centered.
In a microscope, the objective (also called the objective lens) is the lens nearest to the object being examined whereas the lens closest to the eye is termed the ocular (the ...
Without an alternative system or pathway. [L. ob-ligo, pp. -atus, to bind to]
Slanting; deviating from the perpendicular, horizontal, sagittal, or coronal plane of the body. In radiography, a projection that is neither frontal nor lateral. [L. obliquus]
- Litzmann o. inclination of the fetal head so that the biparietal diameter is oblique in relation to the plane of the pelvic brim, the posterior parietal ...
Denoting a structure having an oblique course or direction; a name given, with further qualification, to several muscles. See muscle. [L. slanting, oblique]
Blotting out, especially by filling of a natural space or lumen by fibrosis or inflammation. In radiology, disappearance of the contour of an organ when the adjacent tissue has ...
SYN: medulla o.. [L. fem. of oblongatus, from oblongus, rather long]
A clouded mental state. [L. ob-nubilo, to becloud, obscure, fr. nubes, cloud]
Abbreviation for organic brain syndrome.
One who perceives, notices, or watches; in behavioral research with humans, the investigator or his/her surrogate. [L. observo, to watch]
- nonparticipant o. an investigator who ...
Failure by the observer to measure accurately, resulting in error. Observer variation may be due to the observer's missing a measurement, making an incorrect measurement, or ...
A recurrent and persistent idea, thought, or impulse to carry out an act that is ego-dystonic, that is experienced as senseless or repugnant, and that the individual cannot ...
Having a tendency to perform certain repetitive acts or ritualistic behavior to relieve anxiety, as in o. neurosis ( e.g., a compulsive, ritualistic need to wash one's hands ...
Falling into disuse; denoting the abolition of a function. [L. obsolesco, to grow out of use]
A physician who delivers babies and is in the practice of obstetrics, the art and science of managing pregnancy, labor and the puerperium, the time immediately after delivery.
An obstetrician is a physician who delivers babies and is in the practice of obstetrics while a gynecologist is a physician who specializes in treating diseases of the female ...
The art and science of managing pregnancy, labor and the puerperium (the time after delivery).
* * *
The specialty of medicine concerned with the care of women during pregnancy, ...
1. Firmly adhering to one's own purpose or opinion, even when wrong; not yielding to argument, persuasion, or entreaty. SYN: intractable (2), refractory (2). 2. SYN: ...
Intestinal obstruction; severe constipation. [L. ob, against, + stipo, pp. -atus, to crowd]
Blockage, clogging, or impeded flow, e.g., by occlusion or stenosis. [L. obstructio]
- closed loop o. o. of a segment of intestine either rotated on a fixed point ( volvulus) or ...
Partial or complete blockage of the breathing tubes to the lungs. Obstruction of the airway can be due to different causes including foreign bodies, allergic reactions, ...
Obstructive sleep apnea
Sleep apnea is a breathing disorder characterized by brief interruptions of breathing during sleep. It owes its name to a Greek word, apnea, meaning "want of breath." There are ...
1. Rarely used term for obstructing or clogging. 2. Rarely used term for an agent that obstructs or prevents a normal discharge, especially a discharge from the bowels. [L. ...
To dull or blunt, especially to blunt sensation or deaden pain. [L. ob-tundo, pp. -tusus, to beat against, blunt]
Obstruction or occlusion. [see obturator]
- intermittent self-o. passage of a blunt object in a lumen or meatus to occlude it or to dilate it.
1. Any structure that occludes an opening. 2. Denoting the o. foramen, the o. membrane, or any of several parts in relation to this foramen. 3. A prosthesis used to close an ...
1. Dull in intellect; of slow understanding. 2. Blunt; not acute. [see obtund]
1. Dullness of sensibility. 2. A dulling or deadening of sensibility.
The opposite, the opposite side, the counterpart. For example, mania is thought of as the obverse of depression just as heads is the obverse of tails on a coin.
The principle of scientific parsimony. William of Occam (14th century) stated it thus : “The assumptions introduced to explain a thing must not be multiplied beyond necessity.”
Relating to the occiput; referring to the o. bone or to the back of the head. SYN: occipitalis.
The occiput, occipital structures. [L. occiput]
Relating to the occipital bone and the atlas; denoting the articulation between the two bones.
Relating to the occiput and the bregma; denoting a measurement in craniometry.
1. Relating to the occiput and the forehead. 2. Relating to the occipital and frontal lobe of the cerebral cortex and association pathways that interconnect these regions.
Relating to the occiput and the temple, or the occipital and the temporal bones.
Relating to the nerve fibers leading from the occipital lobe of the cerebral cortex to the thalamus.
The back of the head. The occipital bone is the bone forming the back of the skull — the rear and the rear bottom of the skull. The occipital bone encloses a large oval hole, ...
1 To close, obstruct, or prevent the passage. To occlude an artery is to occlude the flow of blood. 2 To bring together. To occlude the teeth is to align the upper and lower ...
In dentistry, a name given to some articulators.
1. Pertaining to occlusion or closure. 2. In dentistry, pertaining to the contacting surfaces of opposing o. units (teeth or occlusion rims) or the masticating surfaces of the ...
1. The act of closing or the state of being closed. 2. In chemistry, the absorption of a gas by a metal or the inclusion of one substance within another (as in a gelatinous ...
Serving to close; denoting a bandage or dressing that closes a wound and excludes it from the air.
Hidden. Occult blood is hidden from the eye but is nonetheless present and can be detected by chemical tests. Spina bifida occulta is a hidden defect in the spinal column.
* * *
A disease due to a factor in a person's occupation. Occupational medicine was founded by the Italian physician Bernardino Ramazzini (1633-1714). His De Morbis Artificium (On ...
The field of medicine encompassing occupational disease, diseases due to factors in people's occupations. For example, lung disease in miners.
OCD (Obsessive-compulsive disorder)
A psychiatric disorder characterized by obsessive thoughts and compulsive actions, often concerned with cleaning, checking, counting, or hoarding. OCD appears to be rooted in ...
OCD (osteochondritis dissecans)
A condition in which a fragment of bone in a joint is deprived of blood and separates from the rest of the bone, causing soreness and making the joint “give way”. The ...
A genus of motile, nonsporeforming, aerobic bacteria (family Spirillaceae) containing Gram-negative, rigid, helical cells that are 0.3–1.2 μm in diameter. Motile cells ...
1. The simple eye found in many invertebrates. SYN: eyespot (2). 2. Facet of the compound eye of an insect. [L. dim. of oculus, eye]
Morbid fear of crowds. [G. ochlos, a crowd, + phobos, fear]
Severo, Spanish-U.S. biochemist and Nobel laureate, 1905–1993. See O. law.
A mycotoxin produced by Aspergillus ochraceus growing on stored cereal grains. Affects poultry and other animals fed the grain.
- o. A o. produced by some species of ...
A Gram-negative genus of bacteria similar to Alcaligenes and Pseudomonas spp. in their distribution in environmental and water sources and their culture characteristics. These ...
Yellow discoloration of the skin. [G. ochros, pale yellow, + derma, skin]
An instrument for determining the capillary blood pressure; one of two adjacent fingers is compressed by a rubber balloon until blanching of the skin occurs, after which the ...
A rare, autosomal recessive disease characterized by alkapton uria with pigmentation of the cartilages and sometimes tissues such as muscle, epithelial cells, and dense ...
Relating to or characterized by ochronosis.
Albert John, U.S. surgeon, 1858–1925. See O. clamp, O. method.
Obsessive-compulsive personality disorder.
An eight–base-pair sequence in DNA that has a regulatory role; for example, if it is artificially appended to a gene, it will cause that gene to be preferentially expressed in ...
1. SYN: octavalent. 2. An octavalent element or radical. [L. octo, eight]
Applied to fever, the paroxysms of which recur every eighth day, the day of a paroxysm being counted as the first in the computation. [L. octo, eight]
A peptide made up of eight amino acid residues.
Denoting a chemical element or radical having a combining power (valency) of eight. SYN: octad (1).
SYN: vestibulocochlear nerve [CN VIII]. [L.]
A family in the protozoan class Zoomastigophorea; flagellates with six to eight flagella arranged in pairs and a body that is bilaterally symmetric; it includes the common human ...
A sympathomimetic amine; a false neurotransmitter produced by noradrenergic neurons in the presence of monoamine oxidase inhibitors. SYN: norsympatol, norsynephrine.