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Dehydration severe

Contraindications Debilitated patients, severe cardiovascular disease, severe dehydration, severe renal disease, severe sodium depletion... [Pg.705]

Maple syrup urine disease (MSUD) is a recessive disorder in which there is a partial or complete deficiency in branched-chain o-ketoacid dehydrogenase, an enzyme that decarboxylates leucine, isoleucine, and valine (see Figure 20.10). These amino acids and their corre sponding a-keto acids accumulate in the blood, causing a toxic effect that interferes with brain functions. The disease is characterized by feeding problems, vomiting, dehydration, severe metabolic acidosis, and a characteristic maple syrup odor to the urine. If untreated, the disease leads to mental retardation, physical disabilities, and death. [Pg.270]

Derived from these bases, no doubt, by dehydration, several dehydroaporphines have been identified as natural products. These incluyde dehydroisolaureline, dehydrostephanine and de-... [Pg.284]

Not Dehydrated Mild Dehydration Moderate Dehydration Severe Dehydration... [Pg.126]

There are few absolute contraindications to the use of thiopental sodium, but porphyria is generally considered to be completely restrictive [61]. Extra care with both dosage and rate of administration is required in cases of severe haemorrhage, bums dehydration, severe liver disease, status asthmaticus, severe anaemia, raised intracranial pressure, and some metabolic diseases such as thyrotoxicosis and diabetes [61]. [Pg.566]

The effect will be clear from a comparison of the magnetic properties of chromium oxide gel with those of massive crystalline chromic oxide. Chromium oxide gel may be made by precipitation of the hydroxide from a nitrate solution, followed by slow dehydration. Several other processes are available, of which slow reduction from a basic chromate solution is one. On ignition, these gels generally undergo the glow-phenomenon during which they revert to Crystalline chromic oxide. [Pg.75]

The construction of a y-pyrone is essentially the construction of a 1,3,5-tricarbonyl compound since such compounds easily form cyclic hemiacetals then requiring only dehydration. Several methods are available for the assembly of such precursors the synthesis of chelidonic acid (4-pyrone-2,6-dicarboxylic acid) represents the obvious approach of bringing about two Claisen condensations, one on each side of a ketone carbonyl group. Chelidonic acid can be decarboxylated to produce y-pyrone itself. ... [Pg.161]

A solution of the substrate in alcoholic hydrochloric acid (1-3 M, substrate reagent ratio 1 20 to 1 100, w/v) is heated in a sealed vial at 90-100 °C for 2h. For complete dehydration, several successive portions of dry alcohol are evaporated under reduced pressure from the solution of the product. [Pg.122]

If oil and water are mixed as an emulsion, dehydration becomes much more difficult. Emulsions can form as oil-in-water or water-in-oil if mixed production streams are subjected to severe turbulence, as might occur in front of perforations in the borehole. Emulsions can be encouraged to break (or destabilise) using chemicals, heat or just gentle agitation. Chemical destabilisation is the most common method and laboratory tests would normally be conducted to determine the most suitable combination of chemicals. [Pg.248]

Extremely dry (or super-dry ) ethyl alcohol. The yields in several organic preparations e.g., malonic ester syntheses, reduction with sodium and ethyl alcohol, veronal synthesis) are considerably improved by the use of alcohol of 99-8 per cent, purity or higher. This very high grade ethyl alcohol may be prepared in several ways from commercial absolute alcohol or from the product of dehydration of rectified spirit with quicklime (see under 4). [Pg.167]

Thiazole carboxylic acid hydrazides were prepared in a similar way (444, 445). Thus by refluxing thioacetamide or thiobenzamide with y-bromoaceto acetic ester arylhydrazones (83) for several hours in alcohol the 4-carboxythiazole derivatives (84) listed in Table II-ll were obtained (Scheme 36) (656). This reaction is presumed to proceed via dehydration of the intermediate, thiazoline-S-oxide. [Pg.206]

Nitdles may be prepared by several methods (1). The first nitrile to be prepared was propionitdle, which was obtained in 1834 by distilling barium ethyl sulfate with potassium cyanide. This is a general preparation of nitriles from sulfonate salts and is referred to as the Pelou2e reaction (2). Although not commonly practiced today, dehydration of amides has been widely used to produce nitriles and was the first commercial synthesis of a nitrile. The reaction of alkyl hahdes with sodium cyanide to produce nitriles (eq. 1) also is a general reaction with wide appHcabiUty ... [Pg.217]

Adipic acid undergoes the usual reactions of carboxyflc acids, including esterification, amidation, reduction, halogenation, salt formation, and dehydration. Because of its biflmctional nature, it also undergoes several industrially significant polymerization reactions. [Pg.239]

Ma.nufa.cture. Nitroguanidine may be made by several methods. In all the processes guanidine nitrate is the iatermediate which is then dehydrated with sulfuric acid. When used ia propellants, the average particle size of nitroguanidine has to be carefully controlled. [Pg.16]

Several theories have been postulated to explain the various types of flame retardants for cotton. These theories include coating, gas, thermal, and dehydration or chemical. [Pg.485]

Hydroxybenzaldehyde has extensive use as an intermediate in the synthesis of a variety of agricultural chemicals. Halogenation of Nhydroxybenzaldehyde, followed by conversion to the oxime, and subsequent dehydration results in the formation of 3,5-dihalo-4-hydroxybenzonitrile (2). Both the dibromo- and dhodo-compounds are commercially important contact herbicides, hromoxynil [1689-84-5] (2) where X = Br, and ioxynil [1689-83-4]( where X = I respectively (74). Several hydrazone derivatives have also been shown to be active herbicides (70). [Pg.507]

Ma.nufa.cture. Isophorone is produced by aldol condensation of acetone under alkaline conditions. Severe reaction conditions are requited to effect the condensation and partial dehydration of three molecules of acetone, and consequendy raw material iaefftciency to by-products is limited by employing low conversions. Both Hquid- and vapor-phase continuous technologies are practiced (186,193,194). [Pg.494]

The reaction is mn for several hours at temperatures typically below 100°C under a pressure of carbon monoxide to minimise formamide decomposition (73). Conversions of a-hydroxyisobutyramide are near 65% with selectivities to methyl a-hydroxyisobutyrate and formamide in excess of 99%. It is this step that is responsible for the elimination of the acid sludge stream characteristic of the conventional H2SO4—ACH processes. Because methyl formate, and not methanol, is used as the methylating agent, formamide is the co-product instead of ammonium sulfate. Formamide can be dehydrated to recover HCN for recycle to ACH generation. [Pg.252]

Gas and Hquid dehydrators employing molecular sieves provide product gas streams of <0.1 ppmv water and product Hquid streams routinely to <10 ppmv water. AppHcable pressures range from less than one to several hundred times atmospheric pressure. Temperatures range from subzero to several hundred °C. Processing units range in capacity from as Httle as 10 m /h to as much as 10 mr /d in multiple-train units. [Pg.456]

Several crystalline condensed phosphates may also be formed by the dehydration of monosodium phosphate (MSP). Maddrell s salt exists as Form 11 (high temperature MaddreU, NaPO -ll, insoluble metaphosphate-11) and Form 111 (low temperature MaddreU, NaPO -lll, insoluble metaphosphate-111). Both forms are highly polymerized and difficult (slow) to dissolve in water. Mixtures of the two forms are marketed as a dental abrasive for toothpaste formulations containing soluble fluoride. Maddrell s salt is also used with disodium phosphate as a cheese emulsifying aid. [Pg.338]

Salt preserves foods by providing a hostile environment for certain microorganisms. Within foods, salt brine dehydrates bacterial cells, alters osmotic pressure, and inhibits bacterial growth and subsequent spoilage. Dry salt and salt brine are used in several types of curing processes. Pickles are preserved in strong brine before final processing. [Pg.185]


See other pages where Dehydration severe is mentioned: [Pg.272]    [Pg.293]    [Pg.90]    [Pg.238]    [Pg.272]    [Pg.293]    [Pg.90]    [Pg.238]    [Pg.309]    [Pg.2786]    [Pg.272]    [Pg.9]    [Pg.134]    [Pg.247]    [Pg.252]    [Pg.43]    [Pg.135]    [Pg.180]    [Pg.516]    [Pg.256]    [Pg.291]    [Pg.356]    [Pg.446]    [Pg.38]    [Pg.276]    [Pg.117]    [Pg.338]    [Pg.343]    [Pg.150]    [Pg.170]    [Pg.49]    [Pg.255]    [Pg.443]   
See also in sourсe #XX -- [ Pg.118 ]




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