(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.
Quartz
Definition:
(n.) A form of silica, or silicon dioxide (SiO2), occurring in hexagonal crystals, which are commonly colorless and transparent, but sometimes also yellow, brown, purple, green, and of other colors; also in cryptocrystalline massive forms varying in color and degree of transparency, being sometimes opaque.
Example Sentences:
(1) There fore, the adverse effects may be induced by such quartz or silicon compounds.
(2) We have previously shown that intratracheally instilled silica (quartz) produces both morphologic evidence of emphysema and small-airway changes, and functional evidence of airflow obstruction.
(3) Lung sections of rats exposed to quartz particles were significantly different.
(4) Exposures to quartz amounting to less than about 10 per cent of mixed coal mine dust do not generally affect the probability of developing simple pneumoconiosis.
(5) The effect of quartz, bentonite and coal dusts as well as the effect of the artificial mixture of these dusts on TTC reduction and extra-and intra-cellular lactate dehydrogenase activity in peritoneal rat macrophages was determined in vitro.
(6) Silica quartz dust, a direct toxin of macrophages, suppressed demyelination and inflammation if begun at time of virus infection.
(7) As expected the proportion of quartz was greater in lymph nodes and lungs from men who had worked "low" rank (high ash) coal.
(8) Guinea pig splenic lymphocytes and peritoneal macrophage cultures were incubated with quartz (DQ12), Corundum and aspirin as prostaglandin inhibitor.
(9) A surgical system using 308 nm excimer laser radiation transmitted by quartz fibers is described.
(10) Cancer incidence and cause-specific mortality were studied in a male cohort of 94 talc miners and 295 talc millers, exposed to non-asbestiform talc with low quartz content.
(11) The pulsed dye laser can effectively fragment biliary calculi when transmitted through a small-diameter quartz fiber and may be useful as a tool for fragmenting retained common duct stones.
(12) In mice bearing the highly metastatic tumors B16 melanoma and Lewis lung carcinoma (LLC) treated with Hpd and laser light delivered through a quartz fiber optic significantly prolonged the median survival time.
(13) With a long-term (1 and 4 months) introduction of an additional amount of edible fats (beef, hog fats, butter, sunflower seed oil) to intact and intratracheally quartz-dust laden sexually mature male rats an organ-specific reaction to the supply of fat, and in intact rats, also some peculiarities of the reaction depending upon the kind of the introduced fats, were discovered.
(14) Using a fluorescence microscope with quartz optics and an image analyser, it was possible to measure the intracellular concentration of free calcium ions [Ca2+]i in single microvessels for the first time.
(15) The median amount of quartz for all cases, was 0.044 grams.
(16) The microscope is focused on an in-line quartz flow cell incorporated down stream of a microbore HPLC column or directly on an optically clear portion of fused-silica capillary columns for analyte detection.
(17) X-ray diffraction data from samples of 20, 60 and 100 mug quartz on poly-vinyl chloride membrane filters have been collected using a rotating anode x-ray source.
(18) Mentally,” an Uber driver who used to do contract limo work told a reporter from business magazine Quartz last week, “these rating systems affect us a lot… If I am driving somebody who doesn’t live in New York, and they complain that I took the wrong route, how would they know the route that I should have taken?” He went on to note that in 20 years of working with corporate employees, he hadn’t a single customer complaining.
(19) There are closed relations between progressive systemic sclerosis (PSS) and exposure to quartz dust in the GDR.
(20) A 630 nanometer wavelength of light was delivered through a quartz-optical fiber with either a regular flat end for focal illumination or a bulb-type end which produced an isotropic light pattern.