|Medical Dictionary - Dictionary of Medicine and Human Biology|
epiglottis (ep-i-glot′is) [TA]
A leaf-shaped plate of elastic cartilage, covered with mucous membrane, at the root of the tongue, which serves as a diverter valve over the superior aperture of the larynx during the act of swallowing; it stands erect when liquids are being swallowed, but is passively bent over the aperture by solid foods being swallowed. [G. e., fr. epi, on, + glottis, the mouth of the windpipe] bifid e. congenital malformation in which the right and left sides of the e. are not joined; associated with stridor and aspiration in the newborn due to the rotation of the two sides of the e. into the glottis.
Inflammation of the epiglottis, which may cause respiratory obstruction, especially in children; frequently due to infection by Haemophilus influenzae type b. SYN: epiglottiditis.
Unequal conjoined twins in which the smaller, incomplete parasite is attached to the larger autosite at the lower jaw. See conjoined twins, under twin. [epi- + G. gnathos, jaw]
Above the hyoid arch.
Upon the hyoid bone; denoting certain accessory thyroid glands lying above the geniohyoid muscle.
Modification of refractive error by application of a donor cornea to the anterior surface of the patient's cornea from which epithelium has been removed. SYN: epikeratophakic keratoplasty. [epi- + G. keras, horn, + phakos, lens]
A contact lens attached to the corneal stroma to replace the epithelium. [epi- + G. keras, horn, + prosthesis, an addition]
Upon or above a basement membrane. [epi- + L. lamella, dim. of lamina, a thin metal plate]
To extract a hair; to remove the hair from a part by forcible extraction, electrolysis, or loosening at the root by chemical means. Cf.:depilate. [L. e, out, + pilus, a hair]
The act or result of removing hair. SYN: depilation.
1. Having the property of removing hair; relating to epilation. SYN: depilatory (1) , psilotic (2) . SEE ALSO: decalvant. 2. SYN: depilatory (2) .
The connective tissue sheath of nerve fibers near their termination. [epi- lemma, husk]
A tumor resulting from hyperplasia of tissue derived from the true epiblast. [epi- + G. lepis, rind, + -oma, tumor]
SYN: epilepsy. [G.] e. partialis continua 1. a form of epilepsy marked by repetitive clonic muscular contractions with or without major convulsions; 2. simple partial motor status epilepticus of the rolandic cortex, often with myoclonic features; 3. a seizure type seen commonly with Rasmussen encephalitis. SYN: Kojewnikoff epilepsy.
A chronic disorder characterized by paroxysmal brain dysfunction due to excessive neuronal discharge, and usually associated with some alteration of consciousness. The clinical manifestations of the attack may vary from complex abnormalities of behavior including generalized or focal convulsions to momentary spells of impaired consciousness. These clinical states have been subjected to a variety of classifications, none universally accepted to date and, accordingly, the terminologies used to describe the different types of attacks remain purely descriptive and nonstandardized; they are variously based on 1) the clinical manifestations of the seizure (motor, sensory, reflex, psychic or vegetative), 2) the pathologic substrate (hereditary, inflammatory, degenerative, neoplastic, traumatic, or cryptogenic), 3) the location of the epileptogenic lesion (rolandic, temporal, diencephalic regions), and 4) the time of life at which the attacks occur (nocturnal, diurnal, menstrual, etc.). SYN: convulsive state, epilepsia, falling sickness. [G. epilepsia, seizure] anosognosic e. e. characterized by attacks of which the person is unaware. SYN: anosognosic seizures. automatic e. SYN: psychomotor e.. autonomic e. episodes of autonomic dysfunction presumably due to diencephalic irritation. SYN: diencephalic e., vasomotor e., vasovagal e.. benign childhood e. with centrotemporal spikes a specific e. syndrome beginning in childhood and remitting in adolescence, characterized by nocturnal simple partial motor seizures or generalized tonic-clonic seizures. EEG shows centrotemporal spikes that are activated by sleep and an otherwise normal EEG background. centrencephalic e. an imprecise term referring to e. characterized electroencephalographically by bilateral synchronous discharges, and clinically by absence or generalized tonic-clonic seizures. childhood absence e. a generalized e. syndrome characterized by the onset of absence seizures in childhood, typically at age six or seven years. There is a strong genetic predisposition and girls are affected more often than boys. EEG reveals generalized 3-Hz spike-wave activity on a normal background. Prognosis for remission is good if the patient does not also have generalized tonic-clonic seizures. SEE ALSO: absence. SYN: petit mal e., pyknolepsy. childhood e. with occipital paroxysms a benign e. syndrome characterized by frequent occipital spikes often activated by eye closure. It has a seizure semiology that includes visual manifestations; not always remitting later in life. complex precipitated e. a form of reflex e. initiated by specialized sensory stimuli, e.g., certain visual patterns. cortical e. SYN: focal e.. cryptogenic e. SYN: generalized tonic-clonic seizure. diencephalic e. SYN: autonomic e.. early posttraumatic e. seizures beginning within one week after severe head injury. eating e. epileptic, often generalized, seizures provoked by eating; a type of reflex e.. focal e. e. of various etiologies characterized by focal seizures or secondarily generalized tonic-clonic seizures. Ictal symptoms are often related to the brain region where the seizure begins focally. SYN: cortical e., local e., localization-related e. (2) , partial e.. frontal lobe e. a localization-related e. with seizures originating in the frontal lobe. A variety of clinical syndromes exist depending on the exact localization of seizures and clinical semiology of the seizure type. Frontal lobe epilepsies have been divided into several specific syndromes including the syndrome of supplementary motor seizures, cingulate seizures, anterior frontal polar region seizures, orbital frontal seizures, dorsolateral seizures, opercular seizures, and seizures of the motor cortex. generalized e. a major category of e. syndromes characterized by one or more types of generalized seizures. generalized tonic-clonic e. SYN: generalized tonic-clonic seizure. grand mal e. older term for e. characterized by generalized tonic-clonic seizure. idiopathic e. 1. an e. without evident cause; term often used to describe the genetic epilepsies; 2. SYN: generalized tonic-clonic seizure. intractable e. e. not adequately controlled by medication. SYN: pharmacoresistent e.. jacksonian e. SYN: jacksonian seizure. juvenile absence e. a generalized e. syndrome with onset around puberty, characterized by absence seizures and generalized tonic-clonic seizures. EEG often shows a greater than 3 Hz generalized spike wave pattern. juvenile myoclonic e. an e. syndrome typically beginning in early adolescence, and characterized by early morning myoclonic jerks that may progress into a generalized tonic-clonic seizure. A genetic disorder: some families have had gene linkage to chromosome-6. The EEG is characterized by generalized polyspike and wave discharges at 4–6 Hz. Kojewnikoff e. SYN: epilepsia partialis continua. laryngeal e. a form of reflex e. precipitated by coughing. local e. SYN: focal e.. localization-related e. 1. SYN: myoclonus e.. 2. SYN: focal e.. major e. SYN: generalized tonic-clonic seizure. masked e. a form of e. characterized by a paroxysmal disturbance, such as headache or vomiting, associated with an epileptic electroencephalographic pattern. matutinal e. a form of e. which occurs on awakening. myoclonic astatic e. a petit mal variant characterized by atonic (drop attacks) and tonic or tonic-clonic attacks in neurologically disabled (hemiplegic, ataxic, etc.) children with mental retardation; characterized in EEG by 2/sec spike and wave discharges; usually progresses in spite of medication. myoclonus e. [MIM*159800 and MIM*220300] a clinically diverse group of e. syndromes, some benign, some progressive. Many are hereditary with mendelian and nonmendelian mitochondrial inheritance. All are characterized by the occurrence of myoclonus, which may be limited or predominate in the condition. Specific syndromes include cherry red spot myoclonus syndrome, ceroid lipofuscinosis, myoclonic e. with ragged red fibers, and Baltic myoclonus. SYN: localization-related e. (1) . nocturnal e. an e. syndrome characterized by nocturnal seizures only. occipital lobe e. a localization-related e. where seizures originate from the occipital lobe. Symptoms commonly include visual abnormalities during seizures. parietal lobe e. a localization-related e. where seizures originate within the parietal lobe. Seizure semiology may involve abnormalities of sensation. partial e. SYN: focal e.. pattern-sensitive e. a form of reflex e. precipitated by viewing certain patterns. petit mal e. SYN: childhood absence e.. pharmacoresistent e. SYN: intractable e.. photogenic e. a form of reflex e. precipitated by light. posttraumatic e. a convulsive state following and causally related to head injury; with brain damage either manifested clinically or ascertained by special examinations such as computed tomography. To assume causal relationship, the individual must have had no previous e., no cerebral disease, and no other brain trauma. The attacks should have started, depending on the severity of the wounding, within 3 months to 2 years of the alleged trauma and be of a type compatible with the site of injury and the EEG abnormalities. primary generalized e. e. without evidence of focal or multifocal central nervous system disease. Seizures are generalized from onset, both by EEG and clinical criteria. Often a pure genetic form of e.. SEE ALSO: generalized tonic-clonic seizure. procursive e. a psychomotor attack initiated by whirling or running. psychomotor e. attacks with elaborate and multiple sensory, motor, and/or psychic components, the common feature being a clouding or loss of consciousness and amnesia for the event; clinical manifestations may take the form of automatisms; emotional outbursts of temper, anger or show of fear; motor or psychic disturbances; or may be related to any sphere of human activity. Electroencephalographically, the attack is characterized by spike discharges in the temporal lobe, especially in sleep. SEE ALSO: procursive e., visceral e., uncinate e.. SYN: automatic e.. reflex e. seizures which are induced by peripheral stimulation; e.g., audiogenic, laryngeal, photogenic, or other stimulation. SYN: sensory precipitated e.. rolandic e. a benign, autosomal dominant form of e. occurring in children, characterized clinically by arrest of speech, muscular contractions of the side of the face and arm, and epileptic discharges electroencephalographically. [Luigi Rolando] secondary generalized e. a group of e. syndromes of diverse etiologies with diffuse or multifocal cerebral involvement. Patients typically have a variety of generalized seizure types, including tonic, atonic, myoclonic, atypical absence, and generalized tonic-clonic seizures. Partial seizures may also occur. One classic syndrome is the Lennox-Gastaut syndrome. SYN: symptomatic e.. sensory e. focal e. initiated by a somatosensory phenomenon. sensory precipitated e. SYN: reflex e.. sleep e. incorrect term for narcolepsy. somnambulic e. postictal automatism in which the patient walks or runs about exhibiting natural behavior of which he or she has no subsequent remembrance. startle e. a form of reflex e. precipitated by sudden noises. supplementary motor area e. a localization-related e. syndrome in which seizures originate from the supplementary motor area of the mesial frontal lobe. Typical seizure semiology includes sudden bilateral tonic movements, vocalization, and preservation of consciousness. Attacks are often nocturnal. symptomatic e. SYN: secondary generalized e.. temporal lobe e. a localization-related e. with seizures originating from the temporal lobe, most commonly the mesial temporal lobe. The most common pathology is hippocampal sclerosis. SYN: uncinate fit. tonic e. an attack in which the body is rigid. tornado e. a type of focal e. or partial seizure with an aura of severe vertigo and a feeling of being drawn up into space. uncinate e. a form of psychomotor e. or complex partial seizure initiated by a dreamy state and hallucinations of smell and taste, usually the result of a medial temporal lesion. SYN: uncinate attack. vasomotor e. SYN: autonomic e.. vasovagal e. SYN: autonomic e.. visceral e. e., usually psychomotor, in which the attacks are initiated by visceral symptoms or sensations; most cases have their focus in the temporal lobe. e. with grand mal seizures on awakening generalized e. syndrome characterized by onset in the second decade of life, typically with generalized tonic-clonic seizures, of which most occur shortly after awakening (regardless of the time of day) and are exacerbated by sleep deprivation. There is a genetic predisposition and EEG shows one of several generalized patterns of interictal discharges; photosensitivity is common. e. with myoclonic absences a form of generalized e. characterized by absence seizures, severe bilateral rhythmic clonic jerks often associated with tonic contraction, and an EEG 3 Hz spike and wave pattern. Age of onset is usually around seven years and males are more often affected.
Relating to, characterized by, or suffering from epilepsy.
epileptogenic, epileptogenous (ep-i-lep-to-jen′ik, ep-i-lep-toj′e-nus)
Resembling epilepsy; denoting certain convulsions, especially of functional nature. SYN: epileptiform. [G. epilepsia, seizure, epilepsy, + eidos, resemblance]
SYN: tuberous sclerosis.
Upon the lower jaw. [epi- + L. mandibulum, mandible]
Increasing steadily until an acme is reached, then declining; said of a fever. [G. epakmastikos, coming to a height]
Term replacing “crithidial stage,” to avoid confusion with the insect-parasitizing flagellates of the genus Crithidia. In the e. stage the flagellum arises from the kinetoplast alongside the nucleus and emerges from the anterior end of the organism; an undulating membrane is present. [epi- + G. mastix, whip]
Prolonged and profuse menstruation occurring at any time, but most frequently at the beginning and end of menstrual life.
Too frequent menstruation, occurring at any time, but particularly at the beginning and end of menstrual life.
One of two molecules (having more than one chiral center) differing only in the spatial arrangement about a single chiral atom; e.g., α-d-glucose and α-d-galactose (with respect to carbon-4). See sugars. Cf.:anomer. [epi- + G. meros, part]
epimerase (ep′i-mer-as) [EC 5.1]
A class of enzymes catalyzing epimeric changes.
The dorsal part of the myotome. See myotome (3) . [epi- + G. meros, part]
The hooklike anchoring structure at the anterior end of a cephaline gregarine sporozoan; it is left embedded in tissues when the rest of the cephalont is freed in the lumen of the intestine of the invertebrate host. [epi- + G. meros, part]
A microscope with a condenser built around the objective; used for the investigation of opaque, or only slightly translucent, minute specimens. SYN: opaque microscope.
Regeneration of a part of an organism by growth at the cut surface. [epi- + G. morphe, shape]
Incision of the sheath of a muscle. [epimysium + G. tome, a cutting]
epimysium (ep-i-mis′e-um) [TA]
The fibrous connective tissue envelope surrounding a skeletal muscle. SYN: perimysium externum. [epi- + G. mys, muscle]
A catecholamine that is the chief neurohormone of the adrenal medulla of most species; also secreted by neurons. The l-isomer is the most potent stimulant (sympathomimetic) of adrenergic α- and β-receptors, resulting in increased heart rate and force of contraction, vasoconstriction or vasodilation, relaxation of bronchiolar and intestinal smooth muscle, glycogenolysis, lipolysis, and other metabolic effects; used in the treatment of bronchial asthma, acute allergic disorders, open-angle glaucoma, cardiac arrest, and heart block, and as a topical and local vasoconstrictor. Generally used salts are e. hydrochloride and e. bitartrate, the latter most frequently used in topical preparations. SYN: adrenaline. [epi- + G. nephros, kidney, + -ine]
SYN: suprarenal gland. [epi- + G. nephros, kidney]
On a neural arch of a vertebra.
Relating to the epineurium.
epineurium (ep-i-noo′re-um) [TA]
The outermost supporting structure of peripheral nerve trunks, consisting of a condensation of areolar connective tissue; subdivided into those layers that surround the whole nerve trunk (epifascicular e.), and those layers which extend between the nerve fascicles (interfascicular e.). With the endoneurium and perineurium, the e. composes the peripheral nerve stroma. [epi- + G. neuron, nerve] epifascicular e. the portion of the e. which surrounds the whole nerve trunk, in contrast to interfascicular e., which passes down between the nerve fascicles.
epiotic (ep′i-ot′ik, -o′tik)
One of the components of the otic capsule of some vertebrates; in the mammal the petrosal or petrous temporal bone incorporates the various otic elements seen in lower vertebrates. [epi- + G. ous, ear]
1. Usable as a dusting powder. 2. A dusting powder. [G. epi-passo, to sprinkle over]
Upon or about the pericardium.
SYN: nasopharynx. [G. epi, on, over, + pharynx]
A symptom appearing during the course of a disease, not of usual occurrence, and not necessarily associated with the disease.
An overflow of tears upon the cheek, due to imperfect drainage by the tear-conducting passages. SYN: tearing, watery eye (1) . [G. a sudden flow, fr. epi, on, + phero, to bear] atonic e. e. arising from weakness of the orbicularis oculi muscle.
epiphrenic, epiphrenal (ep′i-fren′ik, -fre′nal)
Upon or above the diaphragm. [epi- + G. phren, diaphragm]
epiphysial, epiphyseal (ep-i-fiz′e-al)
Relating to an epiphysis.
1. Premature union of the epiphysis with the diaphysis, resulting in cessation of growth. 2. An operative procedure that partially or totally destroys an epiphysis and may incorporate a bone graft to produce fusion of the epiphysis or premature cessation of its growth; generally undertaken to equalize leg length. [epiphysis + G. desis, binding]
Loosening or separation, either partial or complete, of an epiphysis from the metaphysis of a bone. [epiphysis + G. lysis, loosening]
Any disorder of an epiphysis of the long bones. [epiphysis + G. pathos, suffering]
epiphysis, pl .epiphyses (e-pif′i-sis, -sez) [TA]
A part of a long bone developed from a center of ossification distinct from that of the shaft and separated at first from the latter by a layer of cartilage. [G. an excrescence, fr. epi, upon, + physis, growth] atavistic e. a bone that is independent phylogenetically but is now fused with another bone, e.g., the coracoid process of the scapula. e. cerebri SYN: pineal body. pressure e. a secondary center of ossification in the articular end of a long bone. stippled e. SYN: chondrodysplasia punctata. traction e. a secondary center of ossification at the site of attachment of a tendon.
Inflammation of an epiphysis.
On the pia mater.
Omentum. SEE ALSO: omento-. [G. epiploon]
Rarely used term for hernia of the omentum. [epiplo- + G. kele, hernia]
SYN: greater omentum. [G.]
epipodophyllotoxin (ep-e-po-do- fi′lo-toks′in, -fil′o-toks′in)
Natural product that inhibits topoisomerase II. SEE ALSO: etoposide. [epi- + Podophyllum, genus name of botanical source, + toxin]
In the neighborhood of the pterion.
Unequal conjoined twins in which the smaller, incomplete parasite is attached to the buttock of the larger autosite. See pygomelus, conjoined twins, under twin. [epi- + G. pyge, buttocks]
The connective tissue between the sclera and the conjunctiva. [epi- + sclera]
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