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91.
I. T. L. Bresolin M. Borsoi-Ribeiro W. M. S. C. Tamashiro E. F. P. Augusto M. A. Vijayalakshmi S. M. A. Bueno 《Applied biochemistry and biotechnology》2010,160(7):2148-2165
Monoclonal antibodies (MAbs) have been used for therapies and some analytical procedures as highly purified molecules. Many
techniques have been applied and studied, focusing on monoclonal antibodies purification. In this study, an immobilized metal
affinity chromatography membrane was developed and evaluated for the purification of anti-TNP IgG1 mouse MAbs from cell culture supernatant after precipitation with a 50% saturated ammonium sulfate solution. The chelating
ligands iminodiacetic acid, carboxymethylated aspartic acid (CM-Asp), nitrilotriacetic acid, and tris (carboxymethyl) ethylenediamine
in agarose gels with immobilized Ni(II) and Zn(II) ions were compared for the adsorption and desorption of MAbs. The most
promising chelating ligand—CM-Asp—was then coupled to poly(ethylene vinyl alcohol) (PEVA) hollow fiber membranes. According
to SDS-PAGE and ELISA analyses, a higher selectivity and a purification factor of 85.9 (fraction eluted at 500 mM Tris) were
obtained for IgG1 using PEVA-CM-Asp-Zn(II). The anti-TNP MAb could be eluted under mild pH conditions causing no loss of antigen binding capacity. 相似文献
92.
Daniel Francisco Palacios Juan A. Alfonso Haydn Barros John J. LaBrecque Karla Prez Marian R. Lossada 《Radiation measurements》2008,43(1):77-84
A semi-empirical method to determine radionuclide concentrations in large environmental samples without the use of reference material and avoiding the typical complexity of Monte-Carlo codes is proposed. The calculation of full-energy peak efficiencies was carried out from a relative efficiency curve (obtained from the gamma spectra data), and the geometric (simulated by Monte-Carlo), absorption, sample and intrinsic efficiencies for energies between 130 and 3000 keV. The absorption and sample efficiencies were determined from the mass absorption coefficients, whereas the intrinsic efficiency was approximated by an empirical function. The deviations between calculated and experimental efficiencies for a reference material in most cases are less than 10%. Radionuclide activities in marine sediment samples calculated by the proposed method and by the experimental comparative method were not significantly different. This new method can be used for routine environmental monitoring when uncertainties up to 10% are acceptable. 相似文献
93.
Room temperature Mössbauer spectra of Ga and Al substituted lithium ferrite Li[Fe0.9(AlxGa1?x)0.1]5O8 with x = 0.00, 0.25, 0.50, 0.75 and 1.00 are reported. It is shown that the varying covalence of bonds caused by gallium and aluminium ions can explain the observed values of hyperfine fields and isomer-shifts. 相似文献
94.
We have measured the luminescent properties of single crystals of LiAl5O8:Fe3+. In addition to a zero-phonon line due to Fe3+ in A-sites, we have observed another sharp fluorescent line at 699.2 nm which we assign to Fe3+ occupying B-sites. The excitation spectrum of the B-site Fe3+ shows characteristics similar to those of the A-site Fe3+ but are also shifted towards longer wavelengths. The spectra of the single crystals are compared with those of ordered and disordered powder samples. 相似文献
95.
Louis?Dupaigne Augusto?C.?Ponceaugponce@math.rutgers.edu" title="ponce@ann.jussieu.fr augponce@math.rutgers.edu" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author 《Selecta Mathematica, New Series》2004,10(3):341-358
We present several extensions of the Brezis–Lions Lemma on removable singularities. We also give a positive answer to a question raised by H. Brezis and M. Marcus about an inverse maximum principle for the Laplacian. 相似文献
96.
We extend the classical version of Kato's inequality in order to allow functions u∈L1loc such that Δu is a Radon measure. This inequality has been recently applied by Brezis, Marcus, and Ponce to study the existence of solutions of the nonlinear equation ?Δu+g(u)=μ, where μ is a measure and is a nondecreasing continuous function. To cite this article: H. Brezis, A.C. Ponce, C. R. Acad. Sci. Paris, Ser. I 338 (2004). 相似文献
97.
We demonstrate edge-enhanced imaging produced by volume phase gratings recorded on a polyvinyl alcohol/acrylamide photopolymer. Bragg diffraction, exhibited by volume gratings, modifies the impulse response of the imaging system, facilitating spatial filtering operations with no need for a physical Fourier plane. We demonstrate that Kogelnik's coupled-wave theory can be used to calculate the transfer function for the transmitted and the diffracted orders. The experimental and simulated results agree, and they demonstrate the feasibility of our proposal. 相似文献
98.
Duarte MF Martins F Fernandez MT Langley GJ Rodrigues P Barros MT Costa ML 《Rapid communications in mass spectrometry : RCM》2003,17(9):957-962
A series of derivatives of 2-azidoacetic acid and 2-azidoacetone were synthesized and their behaviour under electron ionization conditions was investigated. This paper reports the electron ionization fragmentation mechanisms for five aliphatic alpha-carbonyl azides, which were clarified by accurate mass measurements and B/E linked scans. The substituent influences the abundance and the nature of the ions resulting from the molecular ion fragmentation. 相似文献
99.
[reaction: see text] The directing ability of an aziridine group for the epoxidation of adjacent double bonds is demonstrated. The aziridine group is also used to effectively protect a double bond in a cycloenone system for a short synthesis of the title compound. 相似文献
100.
Barros W de Sousa PL Engelsberg M 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2003,165(1):175-179
Intermolecular double-quantum coherence (i-DQC) signals in liquids are usually associated with high magnetic fields. We demonstrate that, in a magnetic field of only 16mT, i-DQC imaging of water protons is feasible thanks to the nuclear magnetization enhancement produced by the Overhauser effect. i-DQC images of a phantom containing an aqueous solution of a trityl free radical, with phase encoding in the DQC evolution period or in the acquisition period, are presented. Possible applications of low field i-MQC images are proposed. 相似文献