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61.
The effects of extruded linseed and rapeseed on lipids and FA composition of total, polar and neutral lipids of longissimus thoracis (LT) and semitendinosus (ST) muscles were investigated in 21 Normand cull cows. Animals were assigned in a 100d finishing period to straw (30%) and concentrate (70%) based (C) or the same diet supplemented with linseed (L) or with rapeseed (66%) plus linseed (33%) (RL). Beef polar and neutral lipids were purified by liquid chromatography and their FA analysed by GLC. Trans and cis 18:1, purified by HPLC from total FA methyl esters, were analysed by GLC–MS. L and LR diets did not increase beef lipid deposition, but had modified FA composition of both LT and ST muscles in favouring deposition of 18:3n-3 and 9cis,11tr 18:2 (CLA), mainly to the detriment of 18:1?9 cis (neutral lipids) and 18:2n-6 (polar lipids). However, they did not favour deposition of LC n-3 PUFA in the two muscles, but had increased deposition of trans 18:1 significantly, especially of ?13tr to ?16tr isoforms to the detriment of ?10tr 18:1 (L diet) and of ?11tr 18:1 (RL diet).  相似文献   
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In this paper, we consider the computational power of a new variant of networks of splicing processors in which each processor as well as the data navigating throughout the network are now considered to be polarized. While the polarization of every processor is predefined (negative, neutral, positive), the polarization of data is dynamically computed by means of a valuation mapping. Consequently, the protocol of communication is naturally defined by means of this polarization. We show that networks of polarized splicing processors (NPSP) of size 2 are computationally complete, which immediately settles the question of designing computationally complete NPSPs of minimal size. With two more nodes we can simulate every nondeterministic Turing machine without increasing the time complexity. Particularly, we prove that NPSP of size 4 can accept all languages in NP in polynomial time. Furthermore, another computational model that is universal, namely the 2-tag system, can be simulated by NPSP of size 3 preserving the time complexity. All these results can be obtained with NPSPs with valuations in the set \(\{-1,0,1\}\) as well. We finally show that Turing machines can simulate a variant of NPSPs and discuss the time complexity of this simulation.  相似文献   
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Two well-known active agents, mesalamine (MES) and sucralfate (SUC), were investigated for possible utilization as fixed-dose combination product. The anti-inflammatory action of MES in association with bioadhesiveness and mucosal healing properties of SUC were considered promising for the development of a new compound containing both molecules, aimed as an improved treatment of ulcerative colitis. The present study investigates the capacity of the two active agents to interact and generate a new and stable entity via self-assembling. Spray-drying was used to co-process the two active principles from an aqueous mixture where the ratio MES:SUC was in the range 25:75, 50:50, and 75:25. The structural data (X-Ray, FTIR, SEM, DSC, and 1H NMR) have shown that MES and SUC are interacting leading to complexes with properties differing from those of each separate active agent and from their physical blends. 1H NMR results indicated that complexation occurred when the aqueous suspensions of drugs were mixed, prior to spray-drying. Drug–drug self-assembling was the driving mechanism in the formation of the new entity. Based on the structural data, a hypothetical structure of the complex was proposed. Co-processing of MES and SUC represents a simple and useful procedure to prepare new self-assembled compounds by valorizing the ionic interactions between the two entities. Preliminary studies with oral solid dosage forms based on MES–SUC complexes tested in vitro have shown a controlled MES release, opening the perspective of a new colon-targeted delivery system and a novel class of compounds with therapeutic application in inflammatory bowel diseases.  相似文献   
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Five anthocyanins were detected in the sweet cherry extract as follows: cyanidin 3-rutinoside, cyanidin 3-glucoside, peonidin 3-rutinoside, peonidin 3-glucoside, and pelargonidin 3-rutinoside, whereas the cyanidin 3-rutinoside was found to be in the highest amount. The effect of thermal treatment on the degradation of the polyphenolic compounds in sweet cherry extract was investigated in the range of 70–120 °C by means of fluorescence spectroscopy and spectrophotometric techniques. The fluorescence spectra were dominated by emission bands with maximum ranging from 356 nm at 25 °C to 350 nm at 110 °C. The heating of sweet cherry extract resulted in structural changes that led to a significant decrease in fluorescence intensity when increasing temperature. Degradation rate constants were estimated using a fractional conversion kinetic model. The activation energy values revealed a higher-temperature dependence of antioxidant activity, followed by anthocyanins, total polyphenols, and total flavonoids.  相似文献   
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Regioregular polythiophene-based conductive copolymers with highly crystalline nanostructures are shown to hold considerable promise as the active layer in volatile organic compound (VOC) chemresistor sensors. While the regioregular polythiophene polymer chain provides a charge conduction path, its chemical sensing selectivity and sensitivity can be altered either by incorporating a second polymer to form a block copolymer or by making a random copolymer of polythiophene with different alkyl side chains. The copolymers were exposed to a variety of VOC vapors, and the electrical conductivity of these copolymers increased or decreased depending upon the polymer composition and the specific analytes. Measurements were made at room temperature, and the responses were found to be fast and appeared to be completely reversible. Using various copolymers of polythiophene in a sensor array can provide much better discrimination to various analytes than existing solid state sensors. Our data strongly indicate that several sensing mechanisms are at play simultaneously, and we briefly discuss some of them.  相似文献   
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Although experimental studies in vitro and vivo have been numerous, the effects of laser irradiation on human fibroblast cells are poorly understood. The aim of this study was to assess the influence on three different laser wavelengths on nanoparticles components of the human fibroblast cells from oral tumor. The cells were irradiated by 830, 920, and 2940 nm laser wavelength. The irradiated cells were incubated and their mitochondrial activity was assessed by the MTT assay at 24, 48, and 72 h. It can be concluded that the laser light with 830 nm wavelength stimulates mitochondrial activity compared to the other two wavelengths, which produce inhibition.  相似文献   
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