Nerve Gas: From 1 Different Sources
any gas that disrupts the normal functioning of nerves and thus of the muscles they supply. There are two groups, the G agents and the V agents. The latter are more than 300 times as deadly as mustard gas: one inhalation can kill by paralysing the respiratory muscles. V agents also act through the skin, therefore gas masks are ineffective protection against them.
Inflammation of the mucous coat of the stomach and intestine due to bacterial infection... gastroenteritis
Inflammation of the stomach lining, with either congested and boggy or inflamed membranes. It may be caused by bacteria and yeast or chemical irritation like alcohol, but most frequently it is the result of emotional stress and inappropriate patterns of eating.... gastritis
A usually chronic condition, started by irritation, with congestion in time, leading to edema, blistering, and the formation of an ulcer. Hylobacter infections seem to prolong and aggravate the condition, but the presence alone of the bacteria, without functional impairment, will not begin the disease. Possessing a certain “workaholic” panache...even boasted of in some business circles as if to validate one’s work ethic, it nonetheless is fatal if untreated.... gastric ulcer
See VESTIBULOCOCHLEAR NERVE.... auditory nerve
The seventh cranial nerve (arising from the BRAIN), supplying the muscles of expression in the face, being purely a motor nerve. It enters the face immediately below the ear after splitting up into several branches. (See BELL’S PALSY.)... facial nerve
Pertaining to the stomach.... gastric
A hormone produced by the MUCOUS MEMBRANE in the pyloric part of the STOMACH. The arrival of food stimulates production of the hormone which in turn stimulates the production of gastric juice.... gastrin
An operation performed usually in order to relieve some obstruction to the outlet from the STOMACH. One opening is made in the lower part of the stomach; another in a neighbouring loop of the small intestine. The two are then stitched together.... gastroenterostomy
An operation on the STOMACH by which, when the gullet is blocked by a tumour or other cause, an opening is made from the front of the abdomen into the stomach, so that ?uid food can be passed into the organ.... gastrostomy
The 12th cranial nerve, which supplies the muscles of the tongue, together with some others lying near it. This nerve is responsible for movements required for swallowing and talking. (See also NERVOUS SYSTEM.)... hypoglossal nerve
See ANAESTHESIA – Local anaesthetics.... nerve block
This NERVE arises from the BRACHIAL plexus in the axilla. At ?rst descending posteriorly and then anteriorly, it ends just above the elbow by dividing into the super?cial radial and interosseous nerves. It supplies motor function to the muscles which extend the arm, wrist, and some ?ngers, and supplies sensation to parts of the posterior and lateral aspects of the arm, forearm and hand.... radial nerve
The ?fth cranial nerve (arising from the BRAIN). It consists of three divisions: (1) the ophthalmic nerve, which is purely sensory in function, being distributed mainly over the forehead and front part of the scalp; (2) the maxillary nerve, which is also sensory and distributed to the skin of the cheek, the mucous membrane of the mouth and throat, and the upper teeth; and (3) the mandibular nerve, which is the nerve of sensation to the lower part of the face, the tongue and the lower teeth, as well as being the motor nerve to the muscles concerned in chewing. The trigeminal nerve is of special interest, owing to its liability to NEURALGIA – TRIGEMINAL NEURALGIA, or tic douloureux as it is also known, being the most painful form known.... trigeminal nerve
The fourth cranial nerve (arising from the BRAIN), which acts upon the superior oblique muscle of the EYE.... trochlear nerve
A major NERVE in the arm, it runs from the brachial plexus to the hand. The nerve controls the muscles that move the ?ngers and thumb and conveys sensation from the ?fth and part of the fourth and from the adjacent palm. Muscle weakness and numbness in the areas supplied by the nerve is usually caused by pressure from an abnormal outgrowth from the epicondyle at the bottom of the humerus (upper-arm bone).... ulnar nerve
Also called the pneumogastric nerve, this is the tenth cranial nerve, with many fibers leading to parasympathetic ganglia in internal organs, and can be considered the presynapse starter for the upper parts of the parasympathetic functions.... vagus nerve
The eighth cranial nerve. It consists of two sets of ?bres, which constitute two separate nerves. One is known as the vestibular nerve, which connects the semicircular canals and inner ear to the BRAIN and conveys information on posture and movement of the body; it is the nerve of equilibration or balance. The other is known as the cochlear nerve, which links the COCHLEA (organ that responds to sounds) with the brain and is the nerve of hearing. Disturbance of the former causes giddiness (VERTIGO), whilst disturbance of the latter causes DEAFNESS.... vestibulocochlear nerve
This is the sixth nerve rising from the brain and controls the external rectus muscle of the EYE, which turns the eye outwards. It is particularly liable to be paralysed in diseases of the nervous system, thus leading to an inward squint.... abducent nerve
Speci?cally, this describes the measurement of the tensions of oxygen and carbon dioxide in blood. However, it is commonly used to describe the analysis of a sample of heparinised arterial blood for measurement of oxygen, carbon dioxide, oxygen saturation, pH, bicarbonate, and base excess (the amount of acid required to return a unit volume of the blood to normal pH). These values are vital in monitoring the severity of illness in patients receiving intensive care or who have severe respiratory illness, as they provide a guide to the e?ectiveness of oxygen transport between the outside air and the body tissues. Thus they are both a guide to whether the patient is being optimally ventilated, and also a general guide to the severity of their illness.... blood gases
Pain in the stomach... gastralgia
The large double muscle which forms the chief bulk of the calf, and ends below in the tendo calcaneus.... gastrocnemius
A surgical operation to join the DUODENUM to a hole made in the STOMACH wall to circumvent an obstruction in the gut – for example, PYLORIC STENOSIS – or to improve the passage of food from the stomach into the duodenum.... gastroduodenostomy
The passage along which the food passes, in which it is digested (see DIGESTION), and from which it is absorbed by lymphatics and blood vessels into the circulation. The tract consists of the mouth, pharynx or throat, oesophagus or gullet, stomach, small intestine, and large intestine, in this order. For details, see articles under these headings. The total length in humans is about 9 metres.... gastrointestinal tract
An endoscopic instrument (see ENDOSCOPE) for viewing the interior of the STOMACH. Introduced into the stomach via the mouth and OESOPHAGUS, the long ?exible instrument (also called an oesophagogastroduodenoscope) transmits an image through a ?breoptic bundle or by a small video camera. The operator can see and photograph all areas of the stomach and also take biopsy specimens when required. (See also FIBREOPTIC ENDOSCOPY.)... gastroscope
A branch of the ophthalmic nerve supplying the lacrimal gland and conjunctiva of the EYE.... lacrimal nerve
See NEURON(E).... nerve cell
The NERVE which chie?y supplies the DIAPHRAGM. A phrenic nerve arises on each side of the SPINAL CORD from the third, fourth and ?fth cervical spinal nerves; both follow a long course down the neck, and through the chest to the diaphragm. They play a key part in RESPIRATION through control of the diaphragm. Injury to one nerve paralyses one half of the diaphragm. Occasionally the phrenic nerve may be surgically crushed as part of the treatment to repair a HIATUS HERNIA or, rarely, to stop intractable hiccups.... phrenic nerve
The nerve that operates the lowest muscles of the ?oor of the PELVIS and also the anal SPHINCTER muscle. It may be damaged in childbirth, resulting in INCONTINENCE.... pudendal nerve
See: REFLUX. ... gastro-oesophageal reflux disease
The 11th cranial nerve. Unlike the other cranial nerves, most of the accessory nerve originates from the spinal cord. The small part of the nerve that originates from the brain supplies many muscles of the palate, pharynx (throat), and larynx (voice box). Damage to this part of the nerve may cause difficulty in speaking and swallowing. The spinal part of the nerve supplies large muscles of the neck and back, notably the sternomastoid and trapezius. Damage to the spinal fibres of the nerve paralyses these muscles.... accessory nerve
The part of the vestibulocochlear nerve (the 8th cranial nerve) that is concerned with hearing. It is also known as the auditory nerve.... acoustic nerve
The study of the digestive system and the diseases and disorders affecting it.... gastroenterology
The 3rd cranial nerve, controlling most of the muscles that move the eye. The oculomotor nerve also supplies the muscle that constricts the pupil, that which raises the upper eyelid, and the ciliary muscle, which focuses the eye. The nerve may be damaged due to a fracture to the base of the skull or a tumour. Symptoms include ptosis, squint, dilation of the pupil, inability to focus the eye, double vision, and slight protrusion of the eyeball. (See also trochlear nerve; abducent nerve.)... oculomotor nerve
The first cranial nerve, which conveys sensations of smell as nerve impulses from the nose to the brain. Each of the 2 olfactory nerves has receptors in the mucous membrane lining the nasal cavity. These receptors detect smells and send signals along nerve fibres, which pass through tiny holes in the roof of the nasal cavity and combine to form the olfactory bulbs. From here, nerve fibres come together to form the olfactory nerve, leading to the olfactory centre in the brain. Sense of smell may be lost or impaired due to damage to the olfactory nerves, usually as a result of head injury.... olfactory nerve
The main nerve in each leg and the largest nerve in the body.The sciatic nerves are formed from nerve roots in the spinal cord.... sciatic nerve
See TENS.... transcutaneous electrical nerve stimulation
(Russian) One who is well-behaved Gashah, Gashia, Gashea, Gashiah, Gasheah... gasha
(Spanish) One who is treasured Gasparah, Gasparra, Gasparrah... gaspara
Hair-like appendages in the stomach of most cubozoan jellyfish. They contain nematocysts and aid in digestion.... gastric cirri
A method of gastric decontamination used in the treatment of poisoning. It is not used routinely. Lavage involves the passage of a lubricated tube via the mouth and OESOPHAGUS into the stomach. Patients are positioned on their side with the head lower than the feet. A small quantity of ?uid (300 ml) is passed into the stomach and the contents then drained out (by gravity) by lowering the end of the tube. This is repeated until the solution is clear of particulate matter. The procedure should be done only by an experienced health professional.... gastric lavage
Pain in the stomach... gastrodynia
The involuntary regurgitation of stomach contents or surface acids into the throat, with heartburn; it can be simple or serious.... gastroesophageal reflux
Ulceration of the stomach... gastrohelcosis
Enlargement of the stomach... gastromegaly
Any disease of the stomach... gastropathy
The digestive system of the cnidarian, consisting of the stomach and its connecting canals which perform a similar task to vascular system of higher orders.... gastrovascular cavity
See BELL’S PALSY.... idiopathic facial nerve palsy
A method of electrical stimulation that is being used for the relief of PAIN, including that of MIGRAINE, NEURALGIA and phantom limbs (see AMPUTATION). Known as TENS, its mode of action appears to have some resemblance to that of ACUPUNCTURE. Several controlled trials suggest that it provides at least a modicum of relief of pain after operations, thereby reducing the amount of ANALGESICS that may be called for.... transcutaneous electrical nerve stimulation (tens)
See: REFLUX. GASTRIC ULCER. See: PEPTIC ULCER. ... gastric reflux
See: SEDATIVE. ... nerve relaxant
A group of hormones released from specialized cells in the stomach, pancreas, and intestine that control various functions of the digestive organs. Gastrin, secretin, and cholecystokinin are the best known of these hormones.... gastrointestinal hormones
One of a pair of nerves that carry instructions from the brain to the larynx and send sensations from the larynx to the brain.... laryngeal nerve
Washing out the stomach with water, usually to remove toxins.... lavage, gastric
See nerve, trapped.... trapped nerve
the sixth *cranial nerve (VI), which supplies the lateral rectus muscle of each eyeball, responsible for turning the eye outwards.... abducens nerve
a mixed sensory and motor nerve of the upper arm. It arises from the fifth and sixth cervical segments of the spinal cord and is distributed to the deltoid muscle of the shoulder and the overlying skin.... circumflex nerve
(acoustic nerve, auditory nerve) the nerve connecting the cochlea to the brain and therefore responsible for transmitting the nerve impulses relating to hearing. It forms part of the *vestibulocochlear nerve (cranial nerve VIII).... cochlear nerve
either of two nerves that supply the teeth; they are branches of the trigeminal nerve. The inferior dental nerve supplies the lower teeth and for most of its length exists as a single large bundle; thus anaesthesia of it has a widespread effect (see inferior dental block). The superior dental nerve, which supplies the upper teeth, breaks into separate branches at some distance from the teeth and it is possible to anaesthetize these individually with less widespread effect for the patient.... dental nerve
n. a genus of widely distributed non-bloodsucking beelike flies. The parasitic maggots normally live in the alimentary canal of horses but, rarely, can also infect humans and cause an inflamed itching eruption of the skin (see creeping eruption).... gasterophilus
(gastro-) combining form denoting the stomach. Examples: gastrocolic (relating to the stomach and colon); gastrointestinal (relating to the stomach and intestines).... gastr
n. pathological dilatation of the stomach. This may be caused by gastric outlet obstruction or it may occur as a complication of previous abdominal surgery, trauma, or overeating.... gastrectasia
a form of *bariatric surgery in which a band is placed around the stomach to effectively reduce its size and therefore restrict the amount of food it can accommodate. Weight loss should result. The procedure can be performed either in open operation or laparoscopically. The bands can be of a fixed size or adjustable (to vary calorie intake) by means of a small reservoir situated under the skin into which fluid can be injected or removed by the patient.... gastric banding
any of several procedures of *bariatric surgery that allow food to bypass parts of the gut in order to reduce absorption of nutrients and calories. Such operations often lead to greater weight loss than restrictive procedures, such as *gastric banding and *stomach stapling, but there are significant long-term complications relating to chronic malabsorption and patients must remain under long-term specialist follow-up.... gastric bypass surgery
tubular glands that lie in the mucous membrane of the stomach wall. There are three varieties: the cardiac, parietal (oxyntic), and pyloric glands, and they secrete *gastric juice.... gastric glands
the liquid secreted by the *gastric glands of the stomach. Its main digestive constituents are hydrochloric acid, mucin, *rennin, and pepsinogen. The acid acts on pepsinogen to produce *pepsin, which functions best in an acid medium. The acidity of the stomach contents also kills unwanted bacteria and other organisms that have been ingested with the food. Gastric juice also contains *intrinsic factor, which is necessary for the absorption of vitamin B12.... gastric juice
see stomach stapling.... gastric stapling
n. a rare tumour that secretes the hormone gastrin, which stimulates excessive gastric acid production. Such tumours most frequently occur in the pancreas; about half of them are malignant. Patients present with intractable gastroduodenal ulceration, abdominal pain, and diarrhoea (the *Zollinger–Ellison syndrome). Gastrinomas may be a feature of *MENS type 1.... gastrinoma
combining form. See gastr-.... gastro
a wave of peristalsis produced in the colon by introducing food into a fasting stomach.... gastrocolic reflex
n. see gastroscope.... gastroduodenoscope
n. see oesophagogastroduodenoscopy.... gastroduodenoscopy
n. trade name for meglumine diatrizoate, a water-soluble *contrast medium used in diagnostic radiology, usually in the gastrointestinal tract. It is used in some conditions as a laxative.... gastrografin
the relaxation of the *ileocaecal valve caused by the presence of food in the stomach.... gastroileac reflex
(GIST) a rare type of sarcoma arising from the gastrointestinal tract (usually the stomach), characterized by the presence of the receptor c-kit/CD117 on the surface of the tumour cells, which stimulates division of these cells. It displays a wide range of malignant behaviour. Specific treatment is available with *tyrosine kinase inhibitors.... gastrointestinal stromal tumour
n. a surgical operation in which the *jejunum is joined to an opening made in the stomach. This is usually done in preference to *gastroduodenostomy. See also jejunostomy.... gastrojejunostomy
n. a stone in the stomach, which usually builds up around a *bezoar.... gastrolith
the process in which the stomach contents transiently reflux into the oesophagus. Reflux is a normal process but pathological reflux (see gastro-oesophageal reflux disease) gives rise to symptoms and complications.... gastro-oesophageal reflux
n. a surgical operation in which the oesophagus (gullet) is joined to the stomach, bypassing the natural junction when this is obstructed by *achalasia, *stricture (narrowing), or cancer. This operation is rarely performed.... gastro-oesophagostomy
n. a condition in which the stomach fails to empty at an appropriate rate into the small intestine. Symptoms of bloating, nausea, early satiety, and vomiting are often intermittent in the early stages but can worsen to be a constant feature. It is most commonly seen in long-standing diabetes after the development of neuropathy affecting the parasympathetic nerves to the stomach.... gastroparesis
n. surgical attachment of the stomach to the abdominal wall.... gastropexy
n. surgical alteration of the shape of the stomach without removal of any part. The term was originally used for correction of an acquired deformity, e.g. narrowing due to a peptic ulcer, but has more recently been applied to techniques for reducing the size of the stomach in the treatment of morbid obesity, e.g. vertical banded gastroplasty (see stomach stapling) and *gastric banding.... gastroplasty
n. a congenital defect in the abdominal wall, which during fetal development fails to close to the right of a normal umbilical cord. Bowel herniates through the defect and has no covering; free loops of bowel can be seen floating in the amniotic cavity on ultrasound. Treatment is surgical. Compare exomphalos.... gastroschisis
n. a procedure during abdominal surgery in which the stomach is opened, usually to allow inspection of the interior (e.g. to find a point of bleeding), to remove a foreign body, or to allow the oesophagus to be approached from below (e.g. to pull down a tube through a constricting growth).... gastrotomy
n. an early stage in the development of many animal embryos. It consists of a double-layered ball of cells formed by invagination and movement of cells in the preceding single-layered stage (blastula) in the process of gastrulation. It contains a central cavity, the *archenteron, which opens through the blastopore to the outside. True gastrulation only occurs in the embryos of amphibians and certain fish, but a similar process occurs in the embryonic disc in other vertebrates, including humans.... gastrula
(House–Brackmann score, House–Brackmann scale, House–Brackmann facial weakness scale) a six-point grading system for patients with *Bell’s palsy or other forms of facial nerve palsy. Grade I is normal function; grade VI is a total palsy. [J. W. House and D. E. Brackmann (21st century), US otorhinolarygologists]... house–brackmann facial nerve grading system
(myelinated nerve fibre) see myelin.... medullated nerve fibre
one of the nerves that carry impulses outwards from the central nervous system to bring about activity in a muscle or gland. Compare sensory nerve.... motor nerve
a nerve of the *brachial plexus that supplies some muscles of the arm and the skin of the lateral part of the forearm.... musculocutaneous nerve
a test done to assess the peripheral nervous system. It involves activating the nerves electronically with electrical pulses and measuring the responses obtained.... nerve conduction study
the final part (terminal) of one of the branches of a nerve fibre, where a *neuron makes contact either with another neuron at a synapse or with a muscle or gland cell at a neuromuscular or neuroglandular junction.... nerve ending
any syndrome resulting from pressure on a nerve from surrounding structures. Examples include the *carpal tunnel syndrome and *meralgia paraesthetica.... nerve entrapment syndrome
the long fine process that extends from the cell body of a *neuron and carries nerve impulses. Bundles of nerve fibres running together form a *nerve. Each fibre has a sheath, which in medullated nerve fibres is a relatively thick layer containing the fatty insulating material *myelin.... nerve fibre
(NGF) a protein (see growth factor), consisting of two polypeptide chains, that is required for the development and longevity of some neurons, including those in the sympathetic nervous system and some central nervous system and sensory neurons. Nerve growth factor is necessary for axon growth and also for initiating new neuronal connections with other cells. The role of NGFs in preventing the degeneration of brain cells is being explored in research into Alzheimer’s disease.... nerve growth factor
the electrical activity in the membrane of a *neuron that – by its rapid spread from one region to the next – is the means by which information is transmitted within the nervous system along the axons of the neurons. The membrane of a resting nerve is charged (polarized) because of the different concentrations of ions inside and outside the cell. When a nerve impulse is triggered, a wave of *depolarization spreads, and ions flow across the membrane (see action potential). Until the nerve has undergone *repolarization no further nerve impulses can pass.... nerve impulse
the growth of new nerve tissue, which occurs at a very slow rate (1–2 mm per day) after a nerve has been severed and is often partially or totally incomplete. *Microsurgery has improved the results by facilitating primary repair in the immediate aftermath of injury. See also axonotmesis; neurotmesis.... nerve regeneration
the smallest of the three branches of the *trigeminal nerve. It supplies sensory fibres to the eyeball, conjunctiva, and lacrimal gland, to a small region of the nasal mucous membrane, and to the skin of the nose, brows, and scalp.... ophthalmic nerve
a large branch of the *femoral nerve that arises in the upper thigh, travels down on the inside of the leg, and supplies the skin from the knee to below the ankle with sensory nerves.... saphenous nerve
a nerve that carries information inwards, from an outlying part of the body towards the central nervous system. Different sensory nerves convey information about temperature, pain, touch, taste, etc., to the brain. Compare motor nerve.... sensory nerve
a small subdivision of the *vestibular nerve that carries information from the posterior *semicircular canal to the brain. Singular neurectomy is a surgical procedure to divide the singular nerve, occasionally used in the treatment of *benign paroxysmal positional vertigo.... singular nerve
see accessory nerve.... spinal accessory nerve
any nerve, usually belonging to the autonomic nervous system, that controls the circulation of blood through blood vessels by its action on the muscle fibres within their walls or its action on the heartbeat. The *vagus nerve slows the heart and reduces its output, but sympathetic nerves increase the rate and output of the heart and increase blood pressure by causing the constriction of small blood vessels at the same time.... vasomotor nerve
see gastroplasty; stomach stapling.... vertical banded gastroplasty
the division of the *vestibulocochlear nerve that carries impulses from the semicircular canals, utricle, and saccule of the inner ear to the brain, conveying information about the body’s posture and movements in space and allowing coordination and balance.... vestibular nerve
Health Encyclopedia