(n.) Native phosphate of lime, occurring usually in six-sided prisms, color often pale green, transparent or translucent.
Example Sentences:
(1) Thirty-eight fluids were found to have crystals (monosodium urate (MSU) in 15, calcium pyrophosphate dihydrate (CPPD) in 5, CPPD plus apatite-like crystals in 9, apatite-like clumps alone in 8 and lipid liquid in 1).
(2) Collagen and apatite have been extracted from full bone using well known methods.
(3) These results show that Mg-containing apatites dissolve to a greater extent than Mg-free apatites with the subsequent reprecipitation of Mg-poor apatites.
(4) Both in the HA and the dental mineral systems, the results are consistent with the precipitation of another carbonate-containing apatitic phase during equilibration.
(5) Pure monoclinic or triclinic calcium pyrophosphate dihydrate (CPPD) crystals, apatite crystals or mixtures of these crystals were injected into the synovial-like space created by the rat air pouch to compare the acute inflammation induced by these crystals.
(6) The findings in X-ray analysis had the best correlation with chemical analysis, which was applied mainly to the detection of apatite.
(7) Three presented atypically with calcific periarthritis (due to apatite) in the absence of osteopenia; two had classical presentation with osteopenic fracture; and one was the asymptomatic father of one of the patients with calcific periarthritis.
(8) The radiographic feature is characteristic, and the examination of the material removed from synovial sheath or from calcific deposits allows apatite crystals to be identified.
(9) The findings evidence changed ratio and concentrations of chemical elements and complexes (apatite phases) in the mineral component structure.
(10) The results of the present constant composition (CC) studies show that defect apatites may be formed under conditions of sustained supersaturation with a non-stoichiometric coefficient dependent on the pH of the growth medium.
(11) On histologic examination, the one and two-day-old infarcts exhibited subendocardially located central zones and surrounding peripheral zones, both of which showed distinctive histopathological and histochemical features, including the selective occurrence in the peripheral zones of calcified muscle cells with ultrastructurally demonstrable apatite-like crystals in mitochondria.
(12) The surface is stabilized, i.e., leaching is retarded, by the rapid Ca,P-accumulation within the silica structure before apatite crystals are observed on the surface.
(13) On the other hand, synchrotron X-ray diffraction data clearly indicate that apatite lattice parameters do not change as the crystals get larger.
(14) The present study was undertaken to determine the adsorption isotherms of Mg ions onto synthetic apatites and biominerals in tooth and bone tissues in the presence of other ions of natural occurrence.
(15) The loss of the organic phosphate groups significantly increased the operational lag time, but did not abolish nucleation of apatite crystals by the bone collagen fibrils essentially devoid of Ser(P) and Thr(P).
(16) Synthetic hydroxyapatite has long been used in chromatography because of the bonding capacity apatite surface has for certain proteins and polynucleotides.
(17) A large number of trace elements has been found in calcium stones (whewellite, weddellite, and apatite) and in struvite.
(18) The heats of adsorption of small molecules on bone and apatite surfaces show that these materials have polarizing surfaces which form strong bonds with polar and polarizable molecules.
(19) Fe-containing fluoridated apatites were less well crystallized than Fe-free fluoridated apatites.
(20) The results of kinetic studies are presented for two forms of soluble 3':5'-AMP-dependent protein kinase, obtained by DEAE-cellulose and hydroxyl apatite chromography.
Calcium
Definition:
(n.) An elementary substance; a metal which combined with oxygen forms lime. It is of a pale yellow color, tenacious, and malleable. It is a member of the alkaline earth group of elements. Atomic weight 40. Symbol Ca.
Example Sentences:
(1) In studies of calcium metabolism in 13 unselected patients with untreated sarcoidosis all were normocalcaemic but five had hypercalcuria.
(2) After stimulation with lipopolysaccharide and calcium ionophore A23187, culture supernatants of clones c18A and c29A showed cytotoxic activity against human melanoma A375 Met-Mix and other cell lines which were resistant to the tumor necrosis factor, lymphotoxin and interleukin 1.
(3) The half-life of 45Ca in the various calcium fractions of both types of bone was 72 hours in both the control and malnourished groups except the calcium complex portion of the long bone of the control group, which was about 100 hours.
(4) Calcium alginate dressings have been used in the treatment of pressure ulcers and leg ulcers.
(5) of PLA2 caused marked degranulation of mast cells in the rat mesentery which was facilitated by addition of calcium ion (10 mM) but antagonized by pretreating with three antiinflammatory agents.
(6) Thus adrenaline, via pre- and post-junctional adrenoceptors, may contribute to enhanced vascular smooth muscle contraction, which most likely is sensitized by the elevated intracellular calcium concentration.
(7) It includes preincubation of diluted plasma with ellagic acid and phospholipids and a starting reagent that contains calcium and a chromogenic peptide substrate for thrombin, Tos-Gly-Pro-Arg-pNA.
(8) The results show that endolymph is extremely inhomogenous with respect to calcium potentials.
(9) The occupation of the high affinity calcium binding site by Ca(II) and Mn(II) does not influence the Cu(II) binding process, suggesting that there is no direct interaction between this site and the Cu(II) binding sites.
(10) This was unlike the action of the calcium channel blocker, cadmium, which reduced the calcium action potential and the a.h.p.
(11) Increases in extracellular calcium antagonized the negative inotropic effect.
(12) Plasma membranes were isolated from rat kidney and their transport properties for sodium, calcium, protons, phosphate, glucose, lactate, and phenylalanine were investigated.
(13) In experiments performed to determine whether PtdIns(4,5)P2 hydrolysis induced by TRH may have been caused by the elevation of [Ca2+]i, the following results were obtained: the effect of TRH to decrease the level of PtdIns(4,5)P2 was not reproduced by the calcium ionophore A23187 or by membrane depolarization with 50 mM K+; the calcium antagonist TMB-8 did not inhibit the TRH-induced decrease in PtdIns(4,5)P2; and, most importantly, inhibition by EGTA of the elevation of [Ca2+]i did not inhibit the TRH-induced decrease in PtdIns(4,5)P2.
(14) The distribution of gelsolin, a calcium-dependent actin-severing and capping protein, in the retina of the developing and adult rabbit was studied.
(15) In K+-depolarized basilar arteries, ifenprodil competitively antagonized the response to Ca2+, and this was enhanced by pre-incubation in calcium hopantenate.
(16) Thirty of the 32 women of the calcitonin group and 27 of 28 women of the calcium group finished treatment.
(17) The influence of calcium ions on the electrophoretic properties of phospholipid stabilized emulsions containing various quantities of the sodium salts of oleic acid (SO), phosphatidic acid (SPA), phosphatidylinositol (SPI), and phosphatidylserine (SPS) was examined.
(18) Hypercalcitoninemia was the most pronounced in patients with cardiac rhythm disorders and a simultaneous reduction in total serum calcium.
(19) The effects of low doses of dihydropyridine (DHP) calcium channel antagonists nimodipine, nifedipine, (-)-R-202-791, and amlodipine, the DHP calcium channel agonist BAY K 8644 were investigated on clonic convulsions to pentylenetetrazole (PTZ) in mice.
(20) A comprehensive review of the roentgenographic features of calcium pyrophosphate crystal deposition disease (pseudogout) is presented.