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131.
This study aims to detect aflatoxins (AFs) in dairy cow feed, milk and milk products using a high-performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method. All the validation parameters met the method performance criteria of the European Union. The samples comprised 76 dairy cow feeds and 205 milk and milk products (including yoghurt and yoghurt-based beverage, ayran). AFs were present in 26.3% of the feed samples. Two feed samples exceeded the maximum limit (ML) of 5 µg kg?1 for AFB1 as established by the EU. Nineteen milk samples (21.1%) contained aflatoxin M1 (AFM1) of which three exceeded the EU ML of 0.05 µg l?1. In addition, only two yoghurt samples and one ayran sample contained AFM1, but the levels were lower than the EU ML.  相似文献   
132.
This study revealed the effect of cam setting and number of yarn ply on air permeability and bursting strength of weft-knitted fabrics from glass yarn. Change in cam setting from loose to tight level increased fiber content, and stitch-density; while it decreased loop length. Fabrics with 3-ply yarn exhibited higher fiber content; lower stitch-density; and longer loop length than fabrics with 2-ply yarn. Cam setting showed more pronounced effect on physical properties of fabric than number of yarn ply. Fabrics knitted via tight cam setting level exhibited less air permeability, and higher bursting strength than fabrics knitted via loose cam setting. Fabrics from 3-ply yarn showed less air permeability and higher bursting strength than fabrics from 2-ply yarn. Loop length, wale density, and fiber content were determined as the most effective physical properties on permeability and bursting strength. A negative correlation was detected between air permeability and bursting strength.  相似文献   
133.
A new sampling scheme applicable to the circular ring geometry positron camera is described. The new scheme employs Dichotomic-Ring (two half rings) with linearmotion which allows parallel or fan mode sampling with any desired degree of sampling interval. The parallel and fan data sets obtained by dichotomic motion provide d/4 and d/2 samplings where d is the detector to detector spacing. Computer simulations were made which confirmed the expected performances and results are compared with other conventional schemes such as wobbling and d/2 angular motion sampling schemes for a ring geometry positron camera.  相似文献   
134.
To improve enrichment and isolation of Escherichia coli O157:H7, this study evaluated increased incubation temperature and cefixime-tellurite (CT) on five strains of each of the following bacteria, E. coli, Hafnia alvei, Enterobacter spp., Citrobacter freundii and E. coli O157:H7, and two strains of E. coli O157:nH7. These were grown in pure culture in LST broth with varying cefixime-tellurite concentrations. A range of incubation temperatures from 37 to 46 degrees C was investigated for the inhibition of cohabitant microorganisms. Minced beef, spiked with E. coli O157:H7 and cohabitant microorganisms was investigated. Increased incubation temperature (42 degrees C) and treatment with half of the prescribed amount of cefixime-tellurite by BAM for SMAC agar in enrichment step were the most effective in selectively growing E. coli O157:H7. The results show that E. coli O157:H7 is more resistant to these two conditions than the other cohabitant bacteria.  相似文献   
135.
The key pathogenic event in the onset of Alzheimer's disease (AD) is the aggregation of beta-amyloid (Abeta) peptides into toxic aggregates. Molecules that interfere with this process might act as therapeutic agents for the treatment of AD. The amino acid residues 16-20 (KLVFF) are known to be essential for the aggregation of Abeta. In this study, we have used a first-generation dendrimer as a scaffold for the multivalent display of the KLVFF peptide. The effect of four KLVFF peptides attached to the dendrimer (K(4)) on Abeta aggregation was compared to the effect of monomeric KLVFF (K(1)). Our data show that K(4) very effectively inhibits the aggregation of low-molecular-weight and protofibrillar Abeta(1-42) into fibrils, in a concentration-dependent manner, and much more potently than K(1). Moreover, we show that K(4) can lead to the disassembly of existing aggregates. Our data lead us to propose that conjugates that bear multiple copies of KLVFF might be useful as therapeutic agents for the treatment of Alzheimer's disease.  相似文献   
136.
Epithelial ovarian carcinoma is the deadliest gynecologic malignancy. One reason underlying treatment failure is resistance to paclitaxel. Expression of the microtubule associated protein tau has recently been proposed as a predictor of response to paclitaxel in ovarian carcinoma patients. Expression of tau was probed using immunohistochemistry in 312 specimens of primary, and 40 specimens of metastatic, ovarian carcinoma. Serous epithelial ovarian carcinoma cell line models were used to determine the expression of tau by Western blot and immunofluorescence staining. Subcellular fractionation and Western blot were employed to examine nuclear and cytoplasmic localization of tau. Gene silencing and clonogenic assays were used to evaluate paclitaxel response. Tau was expressed in 44% of all tested cases. Among the primary serous epithelial ovarian carcinoma cases, 46% were tau-positive. Among the metastatic serous epithelial ovarian carcinomas, 63% were tau-positive. Cell culture experiments demonstrated that tau was expressed in multiple isoforms. Three-dimensional collagen I matrix culture conditions resulted in up-regulation of tau protein. Silencing of tau with specific siRNAs in a combination with three-dimensional culture conditions led to a significant decrease of the clonogenic ability of cells treated with paclitaxel. The data suggest that reduction of tau expression may sensitize ovarian carcinoma to the paclitaxel treatment.  相似文献   
137.
The energy distributions and electromagnetic emissions of deuterium ions and electrons in an inertial electrostatic confinement (IEC) unit are reported for low and moderate magnetic field cases. The IEC device has a central wire system inside the grid system of the chamber for the production of the azimuthal magnetic field. The real-time simulations are performed by time integration method by using a finite difference method (FDM) for the physical geometry of device. It is observed that the field induces helical trajectories on the particles especially at the central region where the magnetic force is maximized in a fully ionized Deuterium media. The results prove that the particles have rich dynamics in terms of their trajectories. The effect of negative potential and particle–particle interaction play important roles to determine the trajectories even for low number of ions and electrons. Ion temperatures are calculated as Ti = 6.9 keV after 6 μs for low field case and Ti = 1.517 MeV after 22 μs for medium field case.  相似文献   
138.
Pulses hold excellent nutritive potential owing to high-quality protein content, dietary fibre, minerals, vitamins, oligosaccharides, polyphenols, tannins, phytosterols and several other bioactive constituents. These bio-functional compounds impart significant health benefits by reducing the risk of several chronic complications such as hypertension, cancers, cardiovascular diseases and neurological concerns mainly through anti-oxidative and radical scavenging mechanisms. These high protein ingredients when added to cereal-based extruded snacks not only enhance the nutritive and bioactive profile of the resultant snacks but also modulate the techno-functional attributes of the extrudates. Protein interactions with cereal-based starch and other constituents result in structural variation at the macromolecular level consequently varying the physical, mechanical and techno-functional properties including expansion ratio, bulk density, hydration properties, pasting characteristics and texture. The present review aimed at elaborating the nutritive and bio-functional potential of pulses enriched cereal-based expanded snacks. Further, significant emphasis has been given to the impact of pulse flour incorporation on functional, structural and mechanical properties of the cereal-based extrudates.  相似文献   
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