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991.
992.
The transplantation of stem cells may have a therapeutic effect on the pathogenesis and progression of neurodegenerative disorders. In the present study, we transplanted human mesenchymal stem cells (MSCs) into the lateral ventricle of a triple transgenic mouse model of Alzheimer´s disease (3xTg-AD) at the age of eight months. We evaluated spatial reference and working memory after MSC treatment and the possible underlying mechanisms, such as the influence of transplanted MSCs on neurogenesis in the subventricular zone (SVZ) and the expression levels of a 56 kDa oligomer of amyloid β (Aβ*56), glutamine synthetase (GS) and glutamate transporters (Glutamate aspartate transporter (GLAST) and Glutamate transporter-1 (GLT-1)) in the entorhinal and prefrontal cortices and the hippocampus. At 14 months of age we observed the preservation of working memory in MSC-treated 3xTg-AD mice, suggesting that such preservation might be due to the protective effect of MSCs on GS levels and the considerable downregulation of Aβ*56 levels in the entorhinal cortex. These changes were observed six months after transplantation, accompanied by clusters of proliferating cells in the SVZ. Since the grafted cells did not survive for the whole experimental period, it is likely that the observed effects could have been transiently more pronounced at earlier time points than at six months after cell application.  相似文献   
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The study analysed the effect of low‐concentrated acidic electrolysed water (LCAEW) treatment on meat. Microbiological analysis and colour and sensory quality testing during storage were performed on Longissimus thoracis. FT‐IR and FT‐Raman spectroscopy were used to detect eventual changes in the structure of meat after treatment. Meat samples were sprayed for 120 s with LCAEW (0.001%, 0.01% or 0.1% NaCl solution were electrolysed for 0, 5 or 10 min). The highest reduction in total number of micro‐organisms (3.25 log reduction), yeast and moulds (2.68 log reduction) and psychrotrophs (3.10 log reduction) was observed after spraying the meat samples with 0.1% NaCl electrolysed for 10 min. LCAEW caused a decrease in deoxymyoglobin and metmyoglobin concentration in unstored meat samples. The preliminary sensory studies proved that colour changes are not significant for consumers. The IR and Raman spectra indicate that the structure of compounds of meat tissues are not affected by chlorine and chlorine compounds (LCAEW components). LCAEW has no influence on denaturation of meat protein.  相似文献   
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997.
The conversion technology of fly ash into zeolites   总被引:1,自引:0,他引:1  
This paper presents a sub-pilot scale process of synthesis of Na-P1 zeolite from the coal fly ash. After establishing the appropriate synthesis conditions (20 kg of fly ash, 12 kg of NaOH, 90 dm3 of water, the reaction temperature: 80 °C and reaction time: 36 h), the high-purity (81 wt%) Na-P1 zeolite product was obtained. Its chemical, mineralogical, and textural properties were determined (by means of XRD, XRF, SEM–EDS and ASAP 2020). The synthesized material has a specific BET surface area (88 m2/g) c.a. six times higher than the fly ash from which it has been derived (15 m2/g). The pore-size distribution indicates a mesoporous character of the obtained zeolite, with the following pores size contents: micropores (2.76 %), mesopores (61.81 %), and macropores (35.43 %). The presented technological/production line is fully automated and allows to regulate the conditions of the synthesis process, therefore different types of zeolite materials (including: Na-X, Linde-A, and Na-P1) can be obtained using the same equipment.  相似文献   
998.
The term “cryptome” refers to the subset of cryptic peptides with bioactivities that are often unpredictable and very different from the parent protein. These cryptic peptides are generated by proteolytic cleavage of proteases, whose identification in vivo can be very challenging. In this work, we show that insulin-degrading enzyme (IDE) is able to degrade specific amino acid sequences present in the neuropeptide pro-NPFFA (NPFF precursor), generating some cryptic peptides that are also observed after incubation with rat brain cortex homogenate. The reported experimental findings support the increasingly accredited hypothesis, according to which, due to its wide substrate selectivity, IDE is involved in a wide variety of physiopathological processes.  相似文献   
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1000.
Developing multi-disciplinary products presents cross-disciplinary problems that are difficult to predict and to solve. Unfortunately, those cross-disciplinary problems are often discovered only at a later stage of the design through physical prototypes and can lead to modification of the conceptual design of a product. This is extremely costly and time consuming. This paper describes a new software tool, a Design Interference Detector (DID), which based on qualitative reasoning infers possible problematic physical phenomena that may appear in a design. However, qualitative reasoning techniques often reveal a shortcoming of generating too many negligible solutions. This is a burden to the designer and makes qualitative reasoning practically unusable. Therefore, we developed two filtering methods that filter out such negligible solutions and highlight only potential cross-disciplinary problems. DID with these filtering methods aims particularly at supporting redesign of complex multi-disciplinary products. The paper analyzes advantages and limitations of the filtering methods through a case study.  相似文献   
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