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Meng Gu Natalie M. Zahr Daniel M. Spielman Edith V. Sullivan Adolf Pfefferbaum Dirk Mayer 《NMR in biomedicine》2013,26(2):164-172
Separate quantification of glutamate (Glu) and glutamine (Gln) using conventional MRS on clinical scanners is challenging. In previous work, constant‐time point‐resolved spectroscopy (CT‐PRESS) was optimized at 3 T to detect Glu, but did not resolve Gln. To quantify Glu and Gln, a time‐domain basis set was constructed taking into account metabolite T2 relaxation times and dephasing from B0 inhomogeneity. Metabolite concentrations were estimated by fitting the basis one‐dimensional CT‐PRESS diagonal magnitude spectra to the measured spectrum. This method was first validated using seven custom‐built phantoms containing variable metabolite concentrations, and then applied to in vivo data acquired in rats exposed to vaporized ethanol and controls. Separate metabolite quantification revealed increased Gln after 16 weeks and increased Glu after 24 weeks of vaporized ethanol exposure in ethanol‐treated compared with control rats. Without separate quantification, the signal from the combined resonances of Glu and Gln (Glx) showed an increase at both 16 and 24 weeks in ethanol‐exposed rats, precluding the determination of the independent and differential contribution of each metabolite at each time. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Solid lipid microparticles were investigated as a taste-masking approach for a lipophilic weak base in a suspension. The idea was that the drug concentration in the aqueous phase of a suspension might be reduced by its partitioning into the solid lipid particles. Loratadine, as a model drug, was used to prepare Precirol® ATO 5 microparticles by a Micromixer. The effects of three process variables: drug loading, PVA concentration and water/lipid ratio on the microparticle size, encapsulation efficiency, surface appearance, in-vitro release and drug partitioning in a suspension were studied. Loratadine release was slow in simulated saliva and very fast at the pH of stomach. In suspension of loratadine lipid microparticles, drug was released into the aqueous phase to the same concentration as in a drug suspension. Therefore, the usefulness of these microparticles for taste-masking in liquids is limited. However, they might be useful for taste-masking in solid dosage forms. 相似文献
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Anna Maria Ierardi Natalie Lucchina Mario Petrillo Chiara Floridi Filippo Piacentino Alessandro Bacuzzi Paolo Fonio Federico Fontana Carlo Fugazzola Luca Brunese Gianpaolo Carrafiello 《La Radiologia medica》2014,119(7):483-498
Unresectable locally advanced pancreatic cancer with or without metastatic disease is associated with a very poor prognosis. Ablation techniques are based on direct application of chemical, thermal, or electrical energy to a tumor, which leads to cellular necrosis. Initial studies about ablation therapies of the pancreas were associated with significant morbidity and mortality, which limited widespread adoption. Modifications to the various applications, in particular combining the techniques with high-quality imaging and intra-operative approach has enabled real-time treatment monitoring and significant improvements in safety. Inoperable cases of pancreatic cancer have been treated by various ablation techniques in the last few years with promising results. The purpose of this review is to present the current status of local ablative therapies in the treatment of pancreatic advanced tumor. 相似文献
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Twelve microsatellite markers were developed for the scallop Pecten maximus. The markers were tested in three geographically diverse populations and all markers were polymorphic in all three populations. The mean number of alleles per locus ranged from 2 to 10.67 and the observed and expected heterozygosity ranged from 0.05 to 0.67 and 0.05 to 0.81 respectively. Some loci showed evidence of null alleles and an excess of homozygotes in some populations but 9 loci conformed to Hardy–Weinberg expectations. These new loci can be combined with previously published microsatellites to create a powerful suite of markers for genetic analyses. 相似文献