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21.
Nasim Vahidfar Amir R. Jalilian Yousef Fazaeli Ali Bahrami-Samani Davood Beiki Ali Khalaj 《Journal of Radioanalytical and Nuclear Chemistry》2014,301(1):269-276
166Ho labeled 5,10,15,20-tetrakis(3,4-dimethoxyphenyl) porphyrin, and 5,10,15,20-tetrakis(3,4,5-trimethoxyphenyl) porphyrin ([166Ho]–TDMPP and [166Ho]–TTMPP respectively) were prepared with acceptable radiochemical purity and specific activities. Stability and partition coefficient of the complexes were determined in the final formulations and biodistribution studies in mouse demonstrated high accumulation of [166Ho]–TDMPP in the lung and liver and less excretion through the kidney. while [166Ho]–TTMPP was mostly excreted into intestines and kidneys while lungs were a minor accumulation site. In contrast to other reported radiolanthanide labeled porphyrins these two complexes showed less liver accumulation. Further investigation of their potential therapeutic properties is of interest. 相似文献
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Salamin YI 《Optics letters》2007,32(23):3462-3464
Fields of a radially polarized petawatt laser beam, represented by a truncated series in the diffraction angle epsilon to order epsilon15 and focused to subwavelength waist radius, are shown to accelerate protons and bare nuclei to several hundred MeV per nucleon over a distance equivalent to a few laser wavelengths. 相似文献
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Symmetrical dialkyl phthalates and maleates were synthesized using phosphinite ionic liquid as a catalyst and reaction medium. The results indicated that phosphinite ionic liquid shows better catalytic and reusable performance without using any acid or base catalyst. Under the optimum conditions, using 1-methyl-3-(4-phosphinitebutyl) imidazolium chloride as catalyst, the conversion of phthalic and maleic anhydrides to the corresponding diesters of primary and secondary alcohols was occurred in 72?C85% yields. The diesters of tertiary alcohols and phenols could not be prepared by this method. A kind of widely used plasticizer, dioctyl phthalate, was prepared in good yield under these conditions. The ionic liquid could be reused three times after easy separation from the products without any disposal. 相似文献
27.
Yousef Alavi Gary Chartrand F. R. K. Chung Paul Erds R. L. Graham Ortrud R. Oellermann 《Journal of Graph Theory》1987,11(2):235-249
A connected graph is highly irregular if each of its vertices is adjacent only to vertices with distinct degrees. In this paper we investigate several problems concerning the existence and enumeration of highly irregular graphs as well as their independence numbers, with particular focus on the corresponding problems for highly irregular trees. 相似文献
28.
Yousef Hashem Zahran 《国际流体数值方法杂志》2008,57(6):745-760
We describe a hybrid method for the solution of hyperbolic conservation laws. A third‐order total variation diminishing (TVD) finite difference scheme is conjugated with a random choice method (RCM) in a grid‐based adaptive way. An efficient multi‐resolution technique is used to detect the high gradient regions of the numerical solution in order to capture the shock with RCM while the smooth regions are computed with the more efficient TVD scheme. The hybrid scheme captures correctly the discontinuities of the solution and saves CPU time. Numerical experiments with one‐ and two‐dimensional problems are presented. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
29.
Pijanka JK Kumar D Dale T Yousef I Parkes G Untereiner V Yang Y Dumas P Collins D Manfait M Sockalingum GD Forsyth NR Sulé-Suso J 《The Analyst》2010,135(12):3126-3132
Over the last few years, there has been an increased interest in the study of stem cells in biomedicine for therapeutic use and as a source for healing diseased or injured organs/tissues. More recently, vibrational spectroscopy has been applied to study stem cell differentiation. In this study, we have used both synchrotron based FTIR and Raman microspectroscopies to assess possible differences between human pluripotent (embryonic) and multipotent (adult mesenchymal) stem cells, and how O(2) concentration in cell culture could affect the spectral signatures of these cells. Our work shows that infrared spectroscopy of embryonic (pluripotent) and adult mesenchymal (multipotent) stem cells have different spectral signatures based on the amount of lipids in their cytoplasm (confirmed with cytological staining). Furthermore, O(2) concentration in cell culture causes changes in both the FTIR and Raman spectra of embryonic stem cells. These results show that embryonic stem cells might be more sensitive to O(2) concentration when compared to mesenchymal stem cells. While vibrational spectroscopy could therefore be of potential use in identifying different populations of stem cells further work is required to better understand these differences. 相似文献
30.
A simple, rapid and efficient sample preparation technique, dispersive liquid-liquid microextraction, coupled with gas chromatography-flame ionization detection has been developed to determine N-methylpyrrolidine in cefepime. The effect of various experimental factors on the preparation procedure, such as the nature and volume of extraction and disperser solvents, extraction time, the nature of buffer and its pH, and salt effect, was investigated, optimized and the following results were obtained: extraction solvent, chloroform; dispersive solvent and solvent for dissolving cefepime, a mixture of methanol/water (88:12, v/v); salting out agent, NaCl; and buffer, carbonate/bicarbonate (C=0.5?M, pH=12). The optimized conditions were applied to the real sample (cefepime) for the extraction and determination of N-methylpyrrolidine. The calibration graph is linear from 0.02 to 850?mg/L with the square of correlation coefficient 0.999. LOD and LOQ are 6.4 and 21.2?μg/L in solution, respectively, and 0.2 (2×10(-5) ) and 0.6 (6×10(-5) ) μg/g (%, w/w) in cefepime powder, respectively, using sample size 50?mg. Repeatability of the method is good and RSD% for six repeated experiments (C=170?mg/L) is 6.35%. 相似文献