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1.
The hydrolysis of cyclic adenosine 3′,5′-monophosphate and 2′-deoxythymidylyl(3′-5′)2′-deoxythymidine by Ce(NH 4) 2(NO 3) 6 was kinetically studied. The rate of hydrolysis was fairly proportional to the concentration of [Ce IV 2 (OH) 4] 4+, showing that this is the catalytically active species. According to quantum-chemical calculation, the two Ce(IV) ions in this [Ce IV 2(OH) 4] 4+ cluster are bridged by two OH residues. Upon the complex formation with H 2 PO 4 ? (a model compound for the phosphodiesters), these two Ce(IV) ions bind the two oxygen atoms of the substrate and enhance the electrophilicity of the phosphorus atom. The catalytic mechanism of Ce(IV)-induced hydrolysis of phosphodiesters has been proposed on the basis these results. 相似文献
2.
By the surface modification strategy, a novel high-nuclearity lanthanide complex with a discrete structure, Er 26I(μ 3-OH) 20(μ 3-O) 6(NO 3) 9(IN) 33(OH) 3(H 2O) 33 (noted Er 26, HIN = isonicotinic acid), has been prepared under hydrothermal conditions. The magnetic properties of Er 26 and two analogue dysprosium assemblies Dy 30I(μ 3-OH) 24(μ 3-O) 6(NO 3) 9(IN) 41(OH) 3(H 2O) 38 (noted Dy 26-I) and Dy 26I(μ 3-OH) 20(μ 3-O) 6(NO 3) 9(IN) 31.25(OH) 4.75(H 2O) 41.75 (noted Dy 26-II) have been studied. The results show that the slow relaxation of the magnetization is newly found in Dy 26-I constructed from {Dy 26} and {Dy 4} cluster units. The {Dy 4} units in Dy 26-I, the relative orientation of the complex or the inter-molecular interactions between {Dy 26} cores might play an important role in the origin of this magnetic behavior. 相似文献
3.
Sr 3(PO 4) 2:Dy 3+,Li + phosphors were prepared using a simple high temperature solid method for luminescence enhancement. The structures of the as‐prepared samples agreed well with the standard phase of Sr 3(PO 4) 2, even when Dy 3+ and Li + were introduced. Under ultraviolet excitation at 350 nm, the Sr 3(PO 4) 2:Dy 3+ sample exhibited two emission peaks at 483 nm and 580 nm, which were due to the 4F 9/2 → 6H 15/2 and 4F 9/2 → 6H 13/2 transitions of Dy 3+ ions, respectively. A white light was fabricated using these two emissions from the Sr 3(PO 4) 2:Dy 3+ phosphors. The luminescence properties of Sr 3(PO 4) 2:Dy 3+,Li + phosphors, including emission intensity and decay time, were improved remarkably with the addition of Li + as the charge compensator, which would promote their application in near‐ultraviolet excited white‐light‐emitting diodes. 相似文献
4.
In the present study, Na 3(SO 4) X ( X = F or Cl) halosulphate phosphors have been synthesized by the solid‐state diffusion method. The phase formation of the compounds Na 3(SO 4)F and Na 3(SO 4)Cl were confirmed by X‐ray powder diffraction (XRD) measurement. Photoluminescence (PL) excitation spectrum measurement of Na 3(SO 4)F:Ce 3+ and Na 3(SO 4)Cl:Ce 3+ shows this phosphor can be efficiently excited by near‐ultraviolet (UV) light and presents a dominant luminescence band centred at 341 nm for Ce 3+, which is responsible for energy transfer to Dy 3+and Mn 2+ ions. The efficient Ce 3+ → Dy 3+ energy transfer in Na 3(SO 4)F and Na 3(SO 4)Cl under UV wavelength was observed due to 4 F 9/2 to 6H 15/2 and 6H 13/2 level, while Ce 3+ → Mn 2+ was observed due to 4 T 1 state to 6A 1. The purpose of the present study is to develop and understanding the photoluminescence properties of Ce 3+‐, Dy 3+‐ and Mn 2+‐doped fluoride and chloride Na 3(SO 4) X ( X = F or Cl) luminescent material, which can be the efficient phosphors in many applications, such as scintillation applications, TL dosimetry and the lamp industry, etc. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
5.
This review discusses the photoluminescence (PL) characteristics of halosulfate phosphors developed by us. Halosulfate phosphors KCaSO 4Cl:X,Y (X = Eu or Ce; Y = Dy or Mn) and Na 6(SO 4) 2FCl (doped with Dy, Ce or Eu) were prepared using a solid‐state diffusion method. The mechanism of energy transfer from Eu 2+→Dy 3+, Ce 3+→Dy 3+ and Ce 3+→Mn 2+ has also been studied. Dy 3+ emission in the host at 475 and 570 nm is observed due to 4F 9/2→ 6H 15/2 and 4F 9/2→ 6H 13/2 transition, whereas the PL emission spectra of Na 6(SO 4) 2FCl:Ce phosphor shows Ce 3+ emission at 322 nm due to 5d→4f transition of the Ce 3+ ion. The main property of KCaSO 4Cl is its very high sensitivity, particularly when doped by Dy, Mn or Pb activators. This review also discusses the PL characteristics of some new phosphors such as LiMgSO 4F, Na 6Pb 4(SO 4) 6Cl 2, Na 21Mg(SO 4) 10Cl 3 and Na 15(SO 4) 5F 4Cl. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
6.
Potentiometric titrations of N, N-bis(2-hydroxyethyl)glycine (bicine) in the presence of Ln(III) cations (Ln=La, Pr, Nd and Eu) in the pH range extended to ca. 9.5 reveal formation of two types of binuclear hydroxo complexes Ln 2(bic) 2(OH) 4 and Ln 2(bic)(OH) 4 + (bicH=bicine) in addition to previously reported mononuclear mono- and bis-complexes Ln(bic) 2+ and Ln(bic) 2 +, which predominate at pH below 8. 1H NMR titrations of La(III)-bicine mixtures in D 2O show that the complex formation with bicine is slow in the NMR time scale and confirm formation of hydroxide rather than alkoxide complexes in basic solutions. Formation of a different type of hydroxide species under conditions of an excess of metal over ligand is confirmed by studying the absorption spectra of the Nd(III)-bicine system in the hypersensitive region. The binuclear hydroxide complexes are predominant species at pH above 9 and their stabilities increase in the order La < Pr ≈ Nd < Eu. They show fairly high catalytic activity in the hydrolysis of bis(4-nitrophenyl) phosphate (BNPP) at room temperature. Comparison of concentration and pH-dependences of the reaction rates with the species distribution diagrams shows that the catalytic hydrolysis of BNPP proceeds via a Michaelis-Menten type mechanism, which involves the Ln 2(bic)(OH) 4 + complex as the reactive species. The values of the catalytic rate constants and the Michaelis constants are in the range 0.002-0.004 s −1 and 0.35-1.5 mM, respectively, for all lanthanides studied. The half-life for the hydrolysis of BNPP is reduced from 2000 years to ca. 10 min at 25 °C and pH 9.2 in the presence of 5 mM La(III) and 2.5 mM bicine. 相似文献
7.
KCe(PO 3) 4 doped with Dy 3+,Tb 3+,Yb 3+and Nd 3+ phosphors were synthesized by a solid state diffusion method. The prepared samples were characterized by X‐ray diffraction and photoluminescence. KCe(PO 3) 4 exhibits emission in ultraviolet (UV) region which indicates weak Ce 3+–Ce 3+ interaction. The Ce 3+–Ce 3+energy transfer is not efficient. In light of this, energy transfer from Ce 3+ to other lanthanides like Dy 3+, Tb 3+,Yb 3+ and Nd 3+ is rather surprising. 相似文献
8.
In our search to establish a reference ·OH production system with respect to which the reactivity of copper(II) complexes could then be tested, the influence of free Cu 2+ ions on the Cu +/H 2O 2 reaction has been investigated.This influence depends on the C Cu2+/C Cu+ ratio. At low Cu 2+ concentrations, ·OH damage to various detector molecules decreases with increasing Cu 2+ concentrations until C Cu2+/C Cu+ reaches unity. Above this value, ·OH damage increases sharply until C Cu2+/C Cu+ becomes equal to 5 with salicylate and 2 with deoxyribose, ratios for which the protective effect of Cu 2+ cancels. Finally, at higher concentrations, Cu 2+ ions logically add their own ·OH production to that normally expected from Cu + ions. The possible origin of this unprecedented alternate effect has been discussed. The possible influence of Cu + ions on the generation of ·OH radicals by water gamma radiolysis has also been tested and, as already established for Cu 2+ in a previous work, shown to be nonexistent. This definitely confirms that either form of ionised copper cannot scavenge ·OH radicals in the absence of a Iigand. 相似文献
9.
The luminescent properties and energy transfer (ET) mechanism in the Ln 3+ pair of the RE 3+ (RE = Eu 3+, Ce 3+, Dy 3+ and Sm 3+) doped K 4Ca(PO 4) 2 phosphor were successfully investigated using a conventional high-temperature solid-state reaction. In the near infrared (NIR) range, Ce 3+-doped K 4Ca(PO 4) 2 phosphor exhibited a UV–Vis. emission band, whereas K 4Ca(PO 4) 2:Dy 3+ exhibited characteristic emission bands centred at 481 and 576 nm in the near-ultraviolet excitation range. The possibility of ET from Ce 3+ to Dy 3+ in K 4Ca(PO 4) 2 phosphor was confirmed by a significant increase in the photoluminescence intensity of the Dy 3+ ion based on the spectral overlap of acceptor and donor ions. X-ray diffraction, Fourier-transform infrared and thermogravimetric analysis/differential thermal analysis TGA/DTA were carried out to study phase purity, presence of functional groups and amount of weight loss under different temperature regimes. Therefore, the RE 3+-doped K 4Ca(PO 4) 2 phosphor may be a stable phosphor host for light-emitting diode applications. 相似文献
10.
AbstractThe stability constants of the mixed uranyl-hydroxo-peroxo-carbonato species have been calculated. By incorporating those and including stability constants and corresponding equilibria into the developed model of seawater species distribution enables the dependence of uranyl species on pH to be evaluated. The calculations show that at seawater conditions (pH = 8), 88.3% of total uranyl-ion is in the form UO 2(CO 3) 4-, 11% is in the form UO 2(CO 3) 2(OH) 3-, and 0.5% in the UO 2(CO 3)(OH) 22- mixed-ligand complex form, while in the photic layer, 81.2% of uranyl-ion is in the tricarbonate complex, 10.1% in the form UO 2(CO 3) 2(OH 2) 3-, 7% as UO 2(CO 3) 2(OH) 3-, 0.5% as UO 2(CO 3)(OH) 24- and 0.5% as UO 2(O 2) 22- species. 相似文献
11.
The 31P NMR studies showed that lanthanide ions promote the site-specific hydrolysis of 2,3-Bisphosphoglycerate (BPG) at pH 7.4 by cleaving the 2 phosphomonoester bond. The effect of fourteen trivalent lanthanide ions and Sc 3+, and Y 3+ were compared by the percentage of hydrolysis obtained by determining the inorganic phosphate produced. All the trivalent lanthanide ions promote the hydrolysis, but Sc 3+ not. Among them, Ce 3+ affects the reaction mostly. This was mainly attributed to the autooxidation of Ce 3+ to Ce 4+, since the promoting effect of Ce 3+ is related to the increasing Ce 4+ amount in the solution and depressed by adding sulphite. Ce 4+ promotes the hydrolysis more efficiently than Ce 3+ do. The pseudo first-order rate constant for the hydrolysis of BPG by Ce(SO 4) 2 (18.7 mM) at pH 1 and pH 2, 37 °C is 3.1 h –1 and 0.65 h –1 respectively. A mechanism with a hydroxo species as reactive intermediate was proposed for the trivalent lanthanide ions. The site-specificity was explainable by this mechanism. 相似文献
12.
The individual emission and energy transfer between Ce 3+ and Eu 2+ or Dy 3+ in BaCa(SO 4) 2 mixed alkaline earth sulfate phosphor prepared using a co‐precipitation method is described. The phosphor was characterized by X‐ray diffraction (XRD) and photoluminescence (PL) studies and doped by Ce;Eu and Dy rare earths. All phosphors showed excellent blue–orange emission on excitation with UV light. PL measurements reveal that the emission intensity of Eu 2+ or Dy 3+ dopants is greater than when they are co‐doped with Ce 3+. An efficient Ce 3+ → Eu 2+ [ 2T 2g(4f 65d) → 8S 7/2(4f 7)] and Ce 3+ → Dy 3+ ( 4 F 9/2 → 6H 15/2 and 4 F 9/2 → 6H 13/2) energy transfer takes place in the BaCa(SO 4) 2 host. A strong blue emission peak was observed at 462 nm for Eu 2+ ions and an orange emission peak at 574 nm for Dy 3+ ions. Hence, this phosphor may be used as a lamp phosphor. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
13.
The aluminium (III) released from soil minerals to the soil solution under acid conditions may appear as hexaaquaaluminium
(Al(H 2O) 6
3+, or Al 3+ for convenience) or may react with available ligands to form additional chemical species. That one or more of these species
is rhizotoxic (inhibitory to root elongation) has been known for many decades, but the identity of the toxic species remains
problematical for the following reasons. 1. Several Al species coexist in solution so individual species cannot be investigated
in isolation, even in artificial culture media. 2. The activities of individual species must be calculated from equilibrium
data that may be uncertain. 3. The unexpected or undetected appearance of the extremely toxic triskaidekaaluminium (AlO 4Al 12(OH) 24(H 2O) 12
7+ or Al 13) may cause misatribution of toxicity to other species, especially to mononuclear hydroxy-Al. 4. If H + ameliorates Al 3+ toxicity, or vice versa, then mononuclear hydroxy-Al may appear to be toxic when it is not. 5. The identity and activities
of the Al species contacting the cell surfaces are uncertain because of the H + currents through the root surface and because of surface charges. This article considers the implications of these problems
for good experimental designs and critically evaluates current information regarding the relative toxicities of selected Al
species. It is concluded that polycationic Al (charge >2) is rhizotoxic as are other polyvalent cations. 相似文献
14.
In this work we report on the synthesis, crystal structure, and physicochemical characterization of the novel dinuclear [Fe IIICd II(L)(μ-OAc) 2]ClO 4·0.5H 2O ( 1) complex containing the unsymmetrical ligand H 2L = 2-bis[{(2-pyridyl-methyl)-aminomethyl}-6-{(2-hydroxy-benzyl)-(2-pyridyl-methyl)}-aminomethyl]-4-methylphenol. Also, with this ligand, the tetranuclear [Fe 2IIIHg 2II(L) 2(OH) 2](ClO 4) 2·2CH 3OH ( 2) and [Fe IIIHg II(L)(μ-CO 3)Fe IIIHg II(L)](ClO 4) 2·H 2O ( 3) complexes were synthesized and fully characterized. It is demonstrated that the precursor [Fe III2Hg II2(L) 2(OH) 2](ClO 4) 2·2CH 3OH ( 2) can be converted to ( 3) by the fixation of atmospheric CO 2 since the crystal structure of the tetranuclear organometallic complex [Fe IIIHg II(L)(μ-CO 3)Fe IIIHg II(L)](ClO 4) 2·H 2O ( 3) with an unprecedented {Fe III(μ-O phenoxo) 2(μ-CO 3)Fe III} core was obtained through X-ray crystallography. In the reaction 2 → 3 a nucleophilic attack of a Fe III-bound hydroxo group on the CO 2 molecule is proposed. In addition, it is also demonstrated that complex ( 3) can regenerate complex ( 2) in aqueous/MeOH/NaOH solution. Magnetochemical studies reveal that the Fe III centers in 3 are antiferromagnetically coupled ( J = − 7.2 cm − 1) and that the Fe III-OR-Fe III angle has no noticeable influence in the exchange coupling. Phosphatase-like activity studies in the hydrolysis of the model substrate bis(2,4-dinitrophenyl) phosphate (2,4-bdnpp) by 1 and 2 show Michaelis-Menten behavior with 1 being ~ 2.5 times more active than 2. In combination with kH/ kD isotope effects, the kinetic studies suggest a mechanism in which a terminal Fe III-bound hydroxide is the hydrolysis-initiating nucleophilic catalyst for 1 and 2. Based on the crystal structures of 1 and 3, it is assumed that the relatively long Fe III…Hg II distance could be responsible for the lower catalytic effectiveness of 2. 相似文献
15.
The luminescent properties of europium (Eu)‐ and dysprosium (Dy)‐co‐doped K 3Ca 2(SO 4) 3Cl halosulfate phosphors were analyzed. This paper reports the photoluminescence (PL) properties of K 3Ca 2(SO 4) 3Cl microphosphor doped with Eu and Dy and synthesized using a cost‐effective wet chemical method. The phosphors were characterized by X‐ray diffraction and scanning electron microscopy. The CIE coordinates were calculated to display the color of the phosphor. PL emission of the prepared samples show peaks at 484 nm (blue), 575 nm (yellow), 594 nm (orange) and 617 nm (red). The emission color of the Eu,Dy‐co‐doped K 3Ca 2(SO 4) 3Cl halophosphor depends on the doping concentration and excitation wavelength. The addition of Eu in K 3Ca 2(SO 4) 3Cl:Dy greatly enhances the intensity of the blue and yellow peaks, which corresponds to the 4 F 9/2 → 6H 15/2 and 4 F 9/2 → 6H 13/2 transitions of Dy 3+ ions (under 351 nm excitation). The Eu 3+/Dy 3+ co‐doping also produces white light emission for 1 mol% of Eu 3+, 1 mol% of Dy 3+ in the K 3Ca 2(SO 4) 3Cl lattice under 396 nm excitation, for which the calculated chromaticity coordinates are (0.35, 0.31). Thus, K 3Ca 2(SO 4) 3Cl co‐doped with Eu/Dy is a suitable candidate for NUV based white light‐emitting phosphors technology. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
16.
A yellow‐emitting phosphor NaY(MoO 4) 2:Dy 3+ was synthesized using a solid‐state reaction at 550 °C for 4 h, and its luminescent properties were investigated. Its phase formation was studied using X‐ray powder diffraction analysis, and there were no crystalline phases other than NaY(MoO 4) 2. NaY(MoO 4) 2:Dy 3+ produced yellow emission under 386 or 453 nm excitation, and the prominent luminescence was yellow (575 nm) due to the 4 F 9/2→ 6H 13/2 transition of Dy 3+. For the 575 nm emission, the excitation spectrum had one broad band and some narrow peaks; the peaks were located at 290, 351, 365, 386, 426, 453 and 474 nm. Emission intensities were influenced by the Dy 3+ doping content and a concentration quenching effect was observed; the phenomenon was also proved by the decay curves. Moreover, the Commission International de I'Eclairage chromaticity coordinates of NaY(MoO 4) 2:Dy 3+ showed similar values at different Dy 3+ concentrations, and were located in the yellow region. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
17.
Sr 3MgSi 2O 8:Ce 3+, Dy 3+ phosphors were prepared by a solid‐state reaction technique and the photoluminescence properties were investigated. The emission spectra show not only a band due to Ce 3+ ions (403 nm) but also as a band due to Dy 3+ ions (480, 575 nm) (UV light excitation). The photoluminescence properties reveal that effective energy transfer occurs in Ce 3+/Dy 3+ co‐doped Sr 3MgSi 2O 8 phosphors, and the co‐doping of Ce 3+ could enhance the emission intensity of Dy 3+ to a certain extent by transferring its energy to Dy 3+. The Ce 3+/Dy 3+ energy transfer was investigated by emission/excitation spectra, and photoluminescence decay behaviors. In Sr 2.94MgSi 2O 8:0.01Ce 3+, 0.05Dy 3+ phosphors, the fluorescence lifetime of Dy 3+ (from 3.35 to 27.59 ns) is increased whereas that of Ce 3+ is greatly decreased (from 43.59 to 13.55 ns), and this provides indirect evidence of the Ce 3+ to Dy 3+ energy transfer. The varied emitted color of Sr 3MgSi 2O 8:Ce 3+, Dy 3+ phosphors from blue to white were achieved by altering the concentration ratio of Ce 3+ and Dy 3+. These results indicate Sr 3MgSi 2O 8:Ce 3+, Dy 3+ may be as a candidate phosphor for white light‐emitting diodes. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
18.
In this article, photoluminescence (PL) and thermoluminescence (TL) properties of ZrO 2, ZrO 2:Dy 3+, ZrO 2:Dy 3+–Gd 3+, ZrO 2:Dy 3+–Yb 3+, ZrO 2:Dy 3+–Er 3+, and ZrO 2:Dy 3+–Sm 3+ phosphors synthesized by the Pechini method were investigated. The crystal structure, thermal properties, morphology, PL and TL properties were investigated using X-ray powder diffraction (XRD), differential thermal analysis/thermogravimetric analysis (DTA/TGA), scanning electron microscopy (SEM), PL and TL, respectively. The room temperature emission bands corresponding to 4F 9/2 → 6H J ( J = 9/2, 11/2, 13/2 and 15/2) transitions of Dy 3+ ions were measured. The phosphors were analysed using Tm– TSTOP, variable dose, and computerized glow curve fitting methods. Reusability, dose–response, and fading characteristics were investigated. The phosphors have a natural TL emission that vanished by heating treatment. Moreover, new peaks with similar properties to the natural emissions were observed after high-dose irradiation and long-term fading experiments. The glow curves of the phosphors have 13 individual peaks and many low- and high-temperature satellite peaks. The origin of the peaks is ZrO 2 host material and doping with rare-earth ions (Gd 3+, Dy 3+, Yb 3+, Er 3+ and Sm 3+) does not lead to a new glow peak. The dopants cause drastic changes in individual peak intensities of ZrO 2.The initial fading rates of all the phosphors are relatively fast, but they slow down as time goes on. 相似文献
19.
This work continues a series of studies devoted to complex formation of ions of biogenic metals with the flavonoid dihydroquercetin (DHQ). The interaction of Со2+ ions with DHQ in aqueous solutions has been investigated. It has been found that, at different pH of a solution, complex compounds (CC) with different stoichiometry are formed; a variation of the pH value of a solution from 6.0 to 7.0 results in the formation of compounds (1)–(3) with the metal : flavonoid ligand ratio (Met : L) from 1 : 2 at рН 6.0 (1), through 2 : 3 at pH 6.4–6.7 (2), to 1 : 1 at рН 6.8–7.0 (3). By using the thermogravimetric method and the data of the elemental analysis, the most probable composition of the compounds with the determination of the amount of bound water has been proposed: [CoL2(H2O)4] for (1), [Co2L3(ОН)(H2O)4] for (2), and [CoL(ОН)(H2O)2] for (3). Conditions for the optimization of product yield in the complexation reaction of Со2+ ions with DHQ in an aqueous solution have been determined for compound (2): the рН value of solution 6.7; the reaction time 15 min; the temperature of the reaction solution 90°С; the molar ratio of the initial reagents DHQ : Со2+ 1 : 1.5; the initial concentration of DHQ 0.020 mol/L and that of Со2+ 0.030 mol/L; and the use of CoSO4 ? 7H2O as a source of cobalt ions. The yield of the product is 81.8%. 相似文献
20.
The present studies were conducted to investigate the mechanisms underlying the 1,25-dihydroxycholecalciferol (1,25(OH) 2D 3)-induced increase in intracellular Ca 2+ ([Ca 2+]
i
) in individual CaCo-2 cells. In the presence of 2 mm Ca 2+, 1,25(OH) 2D 3-induced a rapid transient rise in [Ca 2+]
i
in Fura-2-loaded cells in a concentration-dependent manner, which decreased, but did not return to baseline levels. In Ca 2+-free buffer, this hormone still induced a transient rise in [Ca 2+]
i
, although of lower magnitude, but [Ca 2+]
i
then subsequently fell to baseline. In addition, 1,25(OH) 2D 3 also rapidly induced 45Ca uptake by these cells, indicating that the sustained rise in [Ca 2+]
i
was due to Ca 2+ entry. In Mn 2+-containing solutions, 1,25(OH) 2D 3 increased the rate of Mn 2+ influx which was temporally preceded by an increase in [Ca 2+]
i
. The sustained rise in [Ca 2+]
i
was inhibited in the presence of external La 3+ (0.5 mm). 1,25(OH) 2D 3 did not increase Ba 2+ entry into the cells. Moreover, neither high external K + (75 mm), nor the addition of Bay K 8644 (1 μ m), an L-type, voltage-dependent Ca 2+ channel agonist, alone or in combination, were found to increase [Ca 2+]
i
, 1,25(OH) 2D 3 did, however, increase intracellular Na + in the absence, but not in the presence of 2 mm Ca 2+, as assessed by the sodium-sensitive dye, sodium-binding benzofuran isophthalate. These data, therefore, indicate that CaCo-2
cells do not express L-type, voltage-dependent Ca 2+ channels. 1,25(OH) 2D 3 does appear to activate a La 3+-inhibitable, cation influx pathway in CaCo-2 cells. 相似文献
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