Pupil, small

Toxicology of Opivim and its Derivatives.—Opium, its preparations and the alkaloids obtained from it, are all active poisons. They produce drowsiness, stupor, slow and stertorous respiration, contraction of the pupils, small and irregular pulse, coma, and death. The symptoms set in from 10 minutes to 3 hours, sometimes immediately, sometimes only after 18 hours. Death has. occurred in from 45 minutes to 3 days, usually in 5 to 18 hours. After 24 hours the prognosis is favorable. Death has been caused in an adult by one-half grain of acetate of morphia, while 30-grains a day have been taken by those accustomed to its use without ill effects. 

Atropine causes dilation of the pupil of the eye. A drop or two of an aqueous solution, containing 1 part in 130,000 parts of water, introduced into the eye of a cat is sufficient to produce this effect. When warmed with sulphuric acid and a small crystal of potassium dichromate, atropine develops a bitter almond odour. Evaporated to dryness on a water-bath with concentrated nitric acid, it gives a residue which becomes violet on adding a drop of sodium hydroxide solution in alcohol (Vitali s test). With a solution of mercuric chloride atropine gives a yellow to red precipitate of mercuric oxide. 

Deformable mirrors are usually placed at a greatly reduced image of the telescope entrance pupil - the typical diameter of PZT or PMN based deformable mirrors is in the range 10-20 cm. A completely different approach is to make one of the telescope mirrors deformable, and the best choice is the secondary mirror (relatively small and usually coincides with the aperture stop for in-... 

The first effect that we ever observed with very small concentrations of the vapour of D.F.P. was the constriction of the pupil of the eye (see p. 2). As all the intrinsic muscles of the eye... 

Minor exposures also occurred at Dugway Proving Grounds, where remnants of BZ munitions remained in the soil. Workers sometimes came to the dispensary with Big Eye - one dilated pupil - probably caused by a small BZ particle kicked up while walking on the test grid. Physostigmine eye drops were usually sufficient to correct the problem. 

In contrast to muscarine, atropine blocks these actions of acetylcholine and muscarine. Atropine is, therefore, an acetylcholine antagonist. It binds where acetylcholine binds and therefore prevents the binding of the latter but does not activate it. Two molecules cannot occupy the same binding site at the same time. Atropine is isolated from the plant Atropa belladonna. Extracts of this plant have been used for millennia for a variety of purposes. Although large doses are poisonous (Atropos is the name of the Fate who cuts the thread of life), small doses causes dilation of the pupils, a consequence of its action as an acetylcholine antagonist, and has been used for cosmetic purposes by women, hi Itahan, belladonna means beautiful woman. 

The quantity of metal which Davy prepared was very small, and it was not until 1831 that it was first prepared in a coherent form. This was done by the French chemist, Antoine-Alexandre-Brutus Bussy, who was bom at Marseilles on May 29, 1794. He studied at the Ecole Polytechnique for a time, but his interest in chemistry soon led him to abandon his military career and to become apprenticed to a pharmacist. After studying pharmacy at Lyons and at Paris he became a pupil of P.-J. Robiquet, who was then a pr parateur in chemistry at the Ecole de... 

Finally, there may be a small systematic error associated with the lens used. The origin of this is not fully understood, but it may depend on how components around the Rayleigh angle are weighted by the pupil function. Each lens may be calibrated on a well defined reference material to correct for such systematic errors. 

There are considerable difficulties in comparing theory and experiment even in such model experiments. The theoretical calculations are subject to the approximations inherent in the method, and also to uncertainties in the pupil function used to characterize the lens and in the two parameters used to characterize the crack. The experiments are subject to the difficulties of making a crack that is straight and flat to a fraction of the acoustic wavelength used, over the length measured by the line-focus-beam lens, and to the sensitivity of the results in some cases to small changes in x or z. Nevertheless, when all these considerations are taken into account it does seem... 

Blockade of receptors in other tissues elicits miosis (small pupils) and nasal stuffiness. Alpha receptors are expressed in the base of the bladder and the prostate, and their blockade decreases resistance to the flow of urine. Alpha blockers, therefore, are used therapeutically for the treatment of urinary retention due to prostatic hyperplasia (see below). Individual agents may have other important effects in addition to -receptor antagonism (see below). 

ADRENAL MEDULLA HORMONES. Adrenaline (epinephrine) and its immediate biological precursor noradrenaline (norepinephrine, levartei-nol) are the principal hormones of the adult adrenal medulla. See Fig.l. Some of the physiological effects produced by adrenaline arc contraction of the dilator muscle of the pupil of the eye (mydriasis), relaxation of the smooth muscle of the bronchi constriction of most small blood vessels dilation of some blood vessels, notably those in skeletal muscle increase in heart rate and force of ventricular conlraction relaxation of the smooth muscle of the intestinal tract and either contraction or relaxation, or both, of uterine smooth muscle. Electrical stimulation of appropriate sympathetic (adrenergic) nerves can produce all the aforementioned effects with exception of vasodilation in skeletal muscle. 

In the laboratory experiment described above, pentobarbital (450 mg) caused a small but significant decrease in pupil size and a reduction in the constriction velocity of the light reflex. The maximal effect was measured 300 min after oral drug administration. Nystagmus (rhythmical oscillation of the eyeballs) and ptosis (drooping of the upper eyelid) are the eye signs that are most often attributed to ingestion of barbiturates, benzodiazepines, ethanol, and other CNS depressants.26 30 31... 

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