AlcoholAlcohol is one of a group of liquid organic chemicals of similar structure. Alcohol is a colorless volatile flammable liquid. The chemical formula for alcohol is C2H5OH. It is formed by fermentation and contained in wine, beer, whisky and the other fermented and distilled liquors of which it is the intoxicating principle. Alcohol is manufactured principally by fermentation of carbohydrate materials, such as blackstrap molasses, various grains, especially corn, and potatoes, and by hydration of ethylene, being obtained by fractional distillation in a concentration of about 95 per cent with about 5 per cent water. Three alcohols only are of medical interest: ethyl alcohol (ethanol), the basic constituent of alcoholic drinks; methyl alcohol (methanol); and isopropyl alcohol (isopropanol). All alcohols are poisonous, but ethyl alcohol is less poisonous than the others. Ethyl alcohol is used in medicine to harden and clean the skin, and as a rubdown to prevent bedsores. In pharmacy it is chiefly used as a solvent for fats, volatile oils and resins (as in preparing alcoholates, spirits, essences, elixirs, and tinctures), and as a raw material for ethers and esters. Methyl alcohol is used as an antiseptic and as a cooling lotion to the skin. But it is extremely poisonous when drunk and can cause blindness, nerve inflammation (neuritis), and death. Alcohol, taken in the form of alcoholic drinks, is one of the most commonly abused drugs. Alcohol is addictive, and its repeated use often results in the need to drink more and more to produce intoxication. Other symptoms of alcohol abuse are impaired coordination and, often, aggressive behaviour. Inflammation of the stomach lining (gastritis), vomiting, and “hangover” are almost inevitable. Contrary to popular opinion, alcohol acts as a depressant and reduces self – criticism and anxiety. Alcoholic drinks are rich in calories, although they have little or no nutritive value. For that reason, heavy drinkers often have a weight problem. It is important to emphasize that the effects of alcohol increase the potency of such drugs as analgesics, antihistamines, tranquilizers, sedatives, muscle relaxants, and cough and cold drugs. As a result, one drink may have the effect of several and can cause drowsiness, depression, and disulfiram – like reactions*. This is very dangerous and can become fatal. Besides, alcohol is harmful for some groups of patients including epileptics and asthmatics, as well as for pediatric patients and those with gastric and liver disease. New alcohol–free drugs have been developed for these patient categories by the world’s leading pharmaceutical companies. * Disulfiram – like reactions include nausea, vomiting, diarrhea, flushing, tachycardia, increased respiratory rate, and hypotension. (Disulfiram [daI΄sölfIr@m] дисульфирам, дисульфид; антиоксидант, препятствующий нормальной метаболической деградации алкоголя; используется при лечении хронического алкоголизма, когда прием малых доз алкоголя вызывает нежелательную реакцию. Коммерческие названия – тетурам и антабус).
II.10. Назовите по-английски: § 3 способа получения спирта; § 3 разновидности спирта, используемые в медицине; § 3 назначения этилового спирта в медицине и фармации; § основное побочное действие алкоголя при частом употреблении; § 7 групп лекарств, действие которых нарушается под действием алкоголя; § 3 последствия взаимодействия лекарств и алкоголя, упомянутые в тексте.
II.11. Прочтите и переведите дополнительную информацию о спиртах как органических химических соединениях. Объясните, чем различаются структурные формулы первичных, вторичных и третичных спиртов. Alcohols contain a hydroxyl group (–OH) and may be classified as primary, secondary, or tertiary alcohols with their general formulas shown below. Low molecular weight alcohols are water soluble; water solubility decreases as hydrocarbon chain length increases. Alcohols are also lipid soluble. The common reactions of alcohols are esterification and oxidation. Primary alcohols are oxidized to aldehydes and then to acids. Secondary alcohols are oxidized to ketones. Tertiary alcohols ordinarily are not oxidized. On the shelf, alcohols are stable. In vivo, alcohols may undergo oxidation, glucuronidation, or sulfation. R ² | R – CH2 – OH R – CH – OH R – C – OH | | R' R' A B C II.12. Ознакомьтесь со словами к тексту C:
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