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991.
Nilay Bereli Gizem Ertürk M.Aşkın Tümer Rıdvan Say Adil Denizli 《Biomedical chromatography : BMC》2013,27(5):599-607
Antibodies are used in many applications, especially as diagnostic and therapeutic agents. Among the various techniques used for the purification of antibodies, immunoaffinity chromatography is by far the most common. For this purpose, oriented immobilization of antibodies is an important step for the efficiency of purification step. In this study, Fc fragment‐imprinted poly(hydroxyethyl methacrylate) cryogel (MIP) was prepared for the oriented immobilization of anti‐hIgG for IgG purification from human plasma. Non‐imprinted poly(hydroxyethyl methacrylate) cryogel (NIP) was also prepared for random immobilization of anti‐hIgG to compare the adsorption capacities of oriented (MIP/anti‐hIgG) and random (NIP/anti‐hIgG) cryogel columns. The amount of immobilized anti‐hIgG was 19.8 mg/g for the NIP column and 23.7 mg/g for the MIP column. Although the amount of immobilized anti‐hIgG was almost the same for the NIP and MIP columns, IgG adsorption capacity was found to be three times higher than the NIP/anti‐hIgG column (29.7 mg/g) for the MIP/anti‐hIgG column (86.9 mg/g). Higher IgG adsorption capacity was observed from human plasma (up to 106.4 mg/g) with the MIP/anti‐hIgG cryogel column. Adsorbed IgG was eluted using 1.0 m NaCl with a purity of 96.7%. The results obtained here are very encouraging and showed the usability of MIP/anti‐hIgG cryogel prepared via imprinting of Fc fragments as an alternative to conventional immunoaffinity techniques for IgG purification. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
992.
993.
Er Ozge Eksin Ece Soylu Hale Melis Göçmen Bayram Nalbantsoy Ayşe Yurt Fatma Erdem Arzum 《Applied biochemistry and biotechnology》2019,187(4):1539-1550
Applied Biochemistry and Biotechnology - Snake venoms are a natural biological source that has potential therapeutic value with various protein compounds. Disintegrins originally were discovered as... 相似文献
994.
This paper justifies dynamic programming PDEs for optimal control problems with performance criteria involving curvilinear
integrals. The main novel feature, relative to the known theory, is that the multitime dynamic programming PDEs are now connected
to the multitime maximum principle. For the first time, an interesting and useful connection between the multitime maximum
principle and the multitime dynamic programming is given, characterizing the optimal control by means of a PDE system that
may be viewed as a multitime feedback law. 相似文献
995.
Yuri V. Rogovchenko Fatoş Tuncay 《Nonlinear Analysis: Theory, Methods & Applications》2008,69(1):208-221
For a second-order nonlinear differential equation with a damping term, we obtain new oscillation criteria without an assumption that has been required for related results reported in the literature over the last two decades. Two approaches refining the standard integral averaging technique suggested in the paper can be used to derive a variety of simpler oscillation theorems for different classes of nonlinear differential equations, and both sets of oscillation criteria established in the paper are of independent interest. Several examples are provided to illustrate the relevance of the new theorems. 相似文献
996.
Ayşegül Gölcü 《Journal of Analytical Chemistry》2008,63(6):538-543
A sensitive, extraction, derivatization, evaporation and complexation-free, direct spectrophotometric method is developed
for the determination of some anthypertensive drugs such as acebutolol hydrochloride (ACH), atenolol (ATE), and propranolol hydrochloride (PRH) in bulk and pharmaceutical formulations. The optimum conditions for the analysis of aqua solutions of drugs are established.
The method permits the determination of ACH, ATE, and PRH over a concentration range of 37.3–111.9, 53.3–213.1 and 14.8–51.8
μg/mL, respectively. Detection and quantification limits are calculated. The obtained results showed good recoveries of 99.60,
99.20 and 99.80% with relative standard deviations of 0.82, 0.79 and 1.70% for ACH, ATE, and PRH, respectively. The repeatability
and reproducibility of the drugs for aqua media are determined. Precision and accuracy of the developed methods are used for
the recovery studies. The proposed method is applicable for the assay of the three drugs under investigation in dosage forms
and the results are in good agreement with those obtained by the literature method.
The text was submitted by the author in English. 相似文献
997.
Journal of Global Optimization - Channel coding aims to minimize the errors that occur during the transmission of digital information from one place to another. Low-density parity-check codes can... 相似文献
998.
László Csaba Bencze Csaba Paizs Monica Ioana Toşa Florin Dan Irimie 《Tetrahedron: Asymmetry》2010,21(3):356-364
In this Letter the baker’s yeast-mediated biotransformation of variously substituted α-hydroxy- and α-acetoxymethyl-5-phenylfuran-2-yl-ethanones is described. The stereochemical outcome of the reactions was strongly influenced by the nature of the substituents on the phenyl ring. 相似文献
999.
M. Altay Atlıhan Eren Şahiner Feriştah Soykal Alanyalı 《Radiation Physics and Chemistry》2012,81(6):594-598
The luminescence method is a widely used technique for environmental dosimetry and dating archaeological, geological materials. In this study, equivalent dose (ED) and annual dose rate (AD) of an archaeological sample were measured. The age of the material was calculated by means of equivalent dose divided by the annual dose rate. The archaeological sample was taken from Antalya, Turkey. Samples were prepared by the fine grain technique and equivalent dose was found using multiple-aliquot-additive-dose (MAAD) and single aliquot regeneration (SAR) techniques. Also the short shine normalization-MAAD and long shine normalization-MAAD were applied and the results of the methods were compared with each other. The optimal preheat temperature was found to be 200 °C for 10 min. The annual doses of concentrations of the major radioactive isotopes were determined using a high-purity germanium detector and a low-level alpha counter. The age of the sample was found to be 510±40 years. 相似文献
1000.
A novel silica sorbent, silica gel-immobilized 5-aminoisophthalohydrazide (SiO2-APH), was prepared by the condensation of 3-chloropropyl-functionalized silica gel with 5-aminoisophthalohydrazide (APH) derived from dimethyl 5-aminoisophthalate as a starting material and used for separation and preconcentration of Cu, Zn, and Pb metals in water samples using Flame Atomic Absorption Spectrometry (FAAS). The characterization of the new sorbent was carried out by Elemental Analysis, Thermogravimetric Analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR). Important analytical parameters including as pH, amount of sorbent, type and amount of eluting solvent, sample volume, vortex and ultrasonic bath time, matrix ions that effect the developed SiO2-APH-solid phase extraction (SPE) method were investigated and optimum parameters were detected. Recoveries of examined metals were obtained as 98% for Cu and Pb and 101% for Zn. The relative standard deviation (RSD, n = 8) of Cu, Zn and Pb metals were 3.2, 2.8 and 1.6%, respectively. Limit of detections (LODs) (n = 10) were found as 2.7 μg L−1 for Cu, 7.4 μg L−1 for Zn and 3.5 μg L−1 for Pb μg L−1. The accuracy of the new method was assessed by analyzing of TMDA-51.4 and TMDA-70.2 certified reference materials. The results obtained for metals were in a good agreement with certified values. Addition/recovery test was applied to the real well, river, dam and stream water samples to check the accuracy of the method. The results showed that the developed SiO2-APH-SPE method can be effectively used as an alternative method for determination of Cu, Zn, and Pb metals in water samples. 相似文献