(n.) The regular form which a substance tends to assume in solidifying, through the inherent power of cohesive attraction. It is bounded by plane surfaces, symmetrically arranged, and each species of crystal has fixed axial ratios. See Crystallization.
(n.) The material of quartz, in crystallization transparent or nearly so, and either colorless or slightly tinged with gray, or the like; -- called also rock crystal. Ornamental vessels are made of it. Cf. Smoky quartz, Pebble; also Brazilian pebble, under Brazilian.
(n.) A species of glass, more perfect in its composition and manufacture than common glass, and often cut into ornamental forms. See Flint glass.
(n.) The glass over the dial of a watch case.
(n.) Anything resembling crystal, as clear water, etc.
(1) Such a signal must be due to a small ferromagnetic crystal formed when the nerve is subjected to pressure, such as that due to mechanical injury.
(2) A comprehensive review of the roentgenographic features of calcium pyrophosphate crystal deposition disease (pseudogout) is presented.
(3) CW Nd:YAG light transmitted by fiber optic cable and sapphire crystal was applied transsclerally to the ciliary body of pigmented and albino rabbits.
(4) The crystal structure of the biological stain, "acridine orange," has been determined.
(5) Urinalysis revealed a low pH, increased ketones and bilirubin excretion, dark yellowish change in color, the appearance of "leaflet-shaped" crystals and increased red blood cells and epithelial cells in the urinary sediment, increased water intake, decreased specific gravity and decreased sodium, potassium and chloride in the urine.
(6) Early in the regression process, cholesterol esters are reduced at least partly by hydrolysis to yield cholesterol, some of which may crystallize and inhibit rapid regression.
(7) Here we determine the position of bound ADP diffused into the recA crystal.
(8) The virus material in these crystals had been subjected to treatment with EDTA at pH 8.0 before crystallization at pH 6.5.
(9) Results obtained show that chlorophyll is more active than other inhibitors studied and suggest a higher surface adsorption intensity on the primary sources of the crystal surface.
(10) The "Mg(2+)-Sarkosyl crystals" (M band) technique distinguishes between membrane-bound and free intracellular DNA.
(11) The molecular structure of the hexagonal crystal form of porcine pepsin (EC 3.4.23.1), an aspartic proteinase from the gastric mucosa, has been determined by molecular replacement using the fungal enzyme, penicillopepsin (EC 3.4.23.6), as the search model.
(12) In vitro experiments show that these macromolecules are able to interact with specific faces of different crystals, influencing both nucleation and crystal growth.
(13) 2 Each of the drugs significantly increased leucocyte cyclic AMP content within 3 h of the injection of crystals.
(14) For Kevin Phillips, just like Wilfried Zaha, this might have been his final act as a Crystal Palace player.
(15) In ancillary studies, multiple cycles of direct dissolution of UCB crystals revealed a progressive decrease in aqueous solubility of UCB as fine crystals were removed; this effect was minimal in CHCl3.
(16) Six dogs were instrumented with electromagnetic flow probes and subendocardial ultrasonic crystals.
(17) The crystallization of the lipase was successfully carried out.
(18) The values of the energy level distributions in crystals obtained from the measurements and analysis reported here are compared with those obtained by a different method for the same protein complex in frozen solution.
(19) The crystal structure of proteolytically modified human ACT has been solved at 2.7-A resolution (Baumann et al., 1991).
(20) These observations support our hypothesis that calcium pyrophosphate dihydrate crystal deposition in joints is regulated by the physical chemical gel state of the connective tissue matrix.
Dextrorotatory
Definition:
(a.) Turning, or causing to turn, toward the right hand; esp., turning the plane of polarization of luminous rays toward the right hand; as, dextrorotatory crystals, sugars, etc. Cf. Levorotatory.
Example Sentences:
(1) The dextrorotatory enantiomer of fluoxetine was slightly more potent than the levorotatory enantiomer in antagonizing the depletion of brain serotonin by p-chloroamphetamine in rats.
(2) The dextrorotatory morphinan opioid, dextrorphan, which has recently been reported to block the excitation of cortical neurons by N-methyl-D-aspartate, was found at 10-100 microM concentrations to attenuate both morphological and chemical evidence of glutamate neurotoxicity in murine neocortical cell cultures; a similar effect was found with its methyl ester derivative, dextromethorphan.
(3) The differences in antihypertensive activity of racemic and dextrorotatory propranolol cannot be explained by different plasma levels; the data indicate that the hypotensive effect of propranolol is due to beta receptor blockade.
(4) Subsequently, beta-End and levorphanol (10(-8) M), but not the dextrorotatory isomer, stimulated an elongation of the cells.
(5) It is dextrorotatory, [alpha](D) = +138 degrees , and has a pK(a) of 5.1.
(6) A compound, C14H24O2, which induces strong juvenilizing effects in the yellow mealworm, Tenebrio molitor L., following topical application to the pupal stage, was isolated in pure form from the roots of Echinacea angustifolia DC and tentatively identified as dextrorotatory (E)-10-hydroxy-4,10-dimethyl-4,11-dodecadien-2-one.
(7) In hypertensive patients, whose blood pressure was decreased by racemic propranololthe dextrorotatory isomer had no antihypertensive effect.
(8) The dextrorotatory enantiomer prevented the depletion of brain serotonin at any time after p-chloroamphetamine.
(9) The dextrorotatory enantiomer of aminoglutethimide is 38 times more potent than the levoenantiomer in inhibiting aromatization of testosterone by human placental microsomes.
(10) In a separate experiment, 100 micrograms of dextrorotatory and levorotatory gossypol was administered to male mice.
(11) The [3H]Tol2Gdn binding site displays stereoselectivity for dextrorotatory optical isomers of benzomorphan opiates known to have sigma-type behavioral effects.
(12) Fatty acids esterifying these fatty alcohols in M. marinum and M. ulcerans were found to belong to the phthioceranic series (dextrorotatory fatty acids), in contrast to those of the other species (laevorotatory fatty acids called mycocerosic acids), both groups having the same chain length and methyl-branched positions.
(13) The dextrorotatory gossypol, both in rat and mice, had less pronounced effect on the histoarchitecture of the testis in comparison to racemic and levorotatory gossypol.
(14) The non-narcotic dextrorotatory morphinan, dextrorphan, as well as its levorotatory opioid enantiomer, levorphanol, and its O-methyl derivative, dextromethorphan, have recently been shown to antagonize N-methyl-D-aspartate receptor-mediated neurotoxicity.
(15) Contrary to what is generally accepted, the dysphoric and psychotomimetic side effects of sigma opiates are mediated by the levo-and not by the dextrorotatory isomers.
(16) Increases in ventricular myocardial refractoriness and in QTc and paced QT intervals suggest that class III electrophysiologic actions contribute to the antiarrhythmic properties of dextrorotatory sotalol in this animal model.
(17) When dog urine was heated with acid rather than treated with beta-glucuronidase, the isolated p-HPPH contained a small preponderance of the dextrorotatory isomer, probably owing to production of d-p-HPPH from the dihydrodiol metabolite.
(18) The dextrorotatory and levorotatory isomers of chloroquine did not differ in their ability to stimulate the hydrolysis of tRNA by pancreatic ribonuclease A.
(19) The others were the dextrorotatory 2,6-bis-(3',4'-dihydroxyphenyl)-3,7-dioxabicyclo-[3,3,0]-octane 4,8-dione (dehydrodicaffeic acid dilactone) andits antipode.
(20) Another mu-agonist, levorphanol (20, 40, 80, or 160 micrograms) and dextrorphan (160 micrograms), its dextrorotatory isomer, were used next to evaluate opioid specificity.