(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.
Levorotatory
Definition:
(a.) Turning or rotating the plane of polarization towards the left; levogyrate, as levulose, left-handed quartz crystals, etc.
Example Sentences:
(1) In addition, the inhibitory activity of these acyclic analogues was enantioselective, exhibiting a preference, similar to the parent vesamicol, for the levorotatory isomer [(-)-11a vs (+)-11a].
(2) The levorotatory form of 5-hydroxytryptophan significantly improved the ataxia score.
(3) The stereochemistry of this material was established by conversion to levorotatory methyl 4-phthalimido [4(-2)H] butyrate.
(4) Extraction and fractionation of Frullania tamarisci has given, as the only allergenic component isolated, a levorotatory crystalline sutbstance, the structure of which is demonstrated.
(5) As several reports in literature confirmed the greatest antineoplastic activity of L-form in animals, the suggestion of further clinical investigation of levorotatory form as a separate preparation has been put forward.
(6) 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.
(7) The levorotatory compounds of R configuration showed stronger protective and also therapeutic effect in different experimental arrhythmias.
(8) These data indicate that the beta 2-receptor agonistic and anti-permeability actions of terbutaline are found solely in the levorotatory enantiomer.
(9) In five cases in which the levorotatory form of 5-hydroxytryptophan therapy was maintained for 12 months, the effect continued progressively.
(10) Some features of cerebellar ataxia have been reported to regress partially with long-term administration of 5-hydroxytryptophan or levorotatory form of 5-hydroxytryptophan.
(11) The racemic N-alkyl derivatives are more active than the racemic or even the levorotatory N-benzyl compound.
(12) By the consecutive oxidation and hydrolysis reactions a levorotatory intermediate was formed, presumably (-)-2-oxo-4-hydroxy-4-carbohydroxy-5-ureido-imidazoline.
(13) It was shown that the stereodifferentiation of anti-tumor effect of enantiomers was not outstanding although quite consistently in favour of levorotatory forms.
(14) A similar, but less potent neuron-protective effect, was seen with the opioid levorotatory enantiomer of DX, levorphanol (ED50, 40 microM).
(15) Treponemycin is a crystalline light-yellow compound with an mp of 93 to 95 degrees C, levorotatory, and soluble in most organic solvents.
(16) In this report, we identify that a major cortical receptor alteration in these disorders is a reduction in nicotinic receptors measured using both tritiated acetylcholine and levorotatory tritiated nicotine binding.
(17) The therapeutic index of the racemic 13 and its levorotatory enantiomer was about 1.7 times higher than that for ifosfamide and about 2.7 times higher than that for cyclophosphamide.
(18) In a separate experiment, 100 micrograms of dextrorotatory and levorotatory gossypol was administered to male mice.
(19) Among these compounds, the levorotatory 3-acetyl-N-(cyclopropylmethyl)morphinan (12) was found to be an orally active analgesic, comparable in potency to morphine (1), yet only weakly able to substitute for morphine (1) in morphine-dependent rats.
(20) 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.