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41.
Rapid and accurate analysis of platelet count plays an important role in evaluating hemorrhagic status. Therefore, we evaluated platelet counting performance of a hematology analyzer, Celltac F (MEK-8222, Nihon Kohden Corporation, Tokyo, Japan), that features easy use with low reagent consumption and high throughput while occupying minimal space in the clinical laboratory. All blood samples were anticoagulated with dipotassium ethylenediaminetetraacetic acid (EDTA-2K). The samples were stored at room temperature (18^C–22^C) and tested within 4 hours of phlebotomy. We evaluated the counting ability of the Celltac F hematology analyzer by comparing it with the platelet counts obtained by the flow cytometry method that ISLH and ICSH recommended, and also the manual visual method by Unopette (Becton Dickinson Vacutainer Systems). The ICSH/ISLH reference method is based on the fact that platelets can be stained with monoclonal antibodies to CD41 and/or CD61. The dilution ratio was optimized after the precision, coincidence events, and debris counts were confirmed by the reference method. Good correlation of platelet count between the Celltac F and the ICSH/ISLH reference method (r = 0.99, and the manual visual method (r= 0.93) were obtained. The regressions were y = 0.90 x+9.0 and y=1.11x+8.4, respectively. We conclude that the Celltac F hematology analyzer for platelet counting was well suited to the ICSH/ISLH reference method for rapidness and reliability.  相似文献   
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Gliomas are among the most common tumors of the central nervous system and include highly malignant subtypes, such as glioblastoma, which are associated with poor prognosis. Effective treatments are therefore urgently needed. Despite the recent advances in neuroimaging technologies, differentiating gliomas from other brain diseases such as multiple sclerosis remains challenging in some patients, and often requires invasive brain biopsy. Protein tyrosine phosphatase receptor type Z (PTPRZ) is a heavily glycosylated membrane protein that is highly expressed in the central nervous system. Several reports analyzing mouse tumor models suggest that PTPRZ may have potential as a therapeutic target for gliomas. A soluble cleaved form of PTPRZ (sPTPRZ) in the cerebrospinal fluid is markedly upregulated in glioma patients, making it another promising diagnostic biomarker. Intriguingly, PTPRZ is also involved in the process of remyelination in multiple sclerosis. Indeed, lowered PTPRZ glycosylation by deletion of the glycosyltransferase gene leads to reduced astrogliosis and enhanced remyelination in mouse models of demyelination. Here, we review the expression, molecular structure, and biological roles of PTPRZ. We also discuss glioma and demyelinating diseases, as well as the pathological role of PTPRZ and its application as a diagnostic marker and therapeutic target.  相似文献   
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Two main pivotal subjects of research in automotive catalysts were studied by modern X-ray absorption analysis techniques. One is oxygen storage/release behaviour, and the other is sintering inhibition of Pt particles. First, three types of CeO2–ZrO2 (Ce:Zr = 1:1 molar ratio) compounds with different oxygen storage/release capacities and different structural properties were prepared, and the valence change of Ce as a function of temperature during oxygen release/storage processes was investigated. The reduction of surface Ce mainly occurred in the range 100–170 °C, and the reduction of bulk Ce progressed at high temperatures of 170 °C and above. The Ce reduction behaviour depended not only on the homogeneity of the Ce and Zr for bulk reduction at high temperatures but also on the particle size of the CeO2–ZrO2 samples for surface reduction at low temperatures. Secondly, sintering inhibition of Pt in Pt/Al2O3, Pt/MgO and Pt/ceria-based catalysts after 800 °C ageing in air was studied. We found that the Pt–O–M (M = Mg, Ce) bond acted as an anchor and inhibited the sintering of Pt particles on MgO or ceria-based oxide. Especially, it was noteworthy that the Pt–O–Ce4+ bond on the ceria-based support breaks easily through the reduction of Ce (Ce4+ → Ce3+) during the usual stoichiometric and reducing conditions.  相似文献   
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Changes in the microstructure and mechanical properties of Al-7Si-(Fe) alloys by low temperature working have been investigated. The size and shape of eutectic Si and intermetallic AlSiFe compound were controlled by the low temperature working process. This process consisted of repeated cold working at 77 K and recovery treatment at 793 K. By applying this process to the Al-7Si-1Fe alloy, the eutectic Si and acicular Fe compound(β-AlSiFe) phases were broken down to the size of 2-3 μm, with spherical shape. The refined particles were uniformly distributed, and a fine microstructure was obtained. The strength and elongation of Al-7Si-1Fe alloy increased as the temperature was lowered due to the microstructural refinement. This elongation was well reflected in the fracture surface.  相似文献   
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The production process for expanded polypropylene foam beads (EPP), which consists of steaming, depressurizing, cooling, and ageing operations, was consistently simulated by a set of mathematical models. The models, developed from Yang and Lee's ageing models (Yang and Lee, J. Cell. Plast., 39 , 59 (2003)) for extrusion foam products, were extended in terms of the fundamental aspects of mass and heat transport phenomena. Evaporation and condensation of blowing agents and heat conduction during the steam chest molding and ageing processes were modeled. The governing equations were established by integrating the mass transfer equations of steam and air at the intercellular walls with the constitutive equations of evaporation and condensation in each cell, the equation of heat conduction from the mold to the foam, and the mechanical force balance equation on the cell walls. The models simulate the stress exerted on the steaming chest mold and predict the expansion behavior of cells in the EPP bead‐foam board throughout the ageing process. A sensitivity analysis was also performed by the models to find the key factors which might allow the theoretical determination of the ejection time and shortening of the length of the ageing process. POLYM. ENG. SCI., 48:107–115, 2008. © 2007 Society of Plastics Engineers  相似文献   
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The distribution of nano-sized silica in binary rubber blends is characterized by scanning transmission electron microscopy (STEM) tomography combined with energy dispersive X-ray spectrometry (EDX). 3D distribution of silica is visualized by STEM-EDX tomography with the tilt-series of silicon elemental maps, while the phase-separated morphologies of polyisoprene rubber (IR) and styrene-butadiene rubber (SBR) are visualized by STEM-tomography in high-angle-annular-dark field (HAADF) mode. The combination of STEM-EDX and STEM-HAADF tomography enables us to determine the distribution of silica between the two rubber phases quantitatively even with high contents of silica up to 70 phr (weight parts per hundred rubber). It is found that silica is preferentially distributed in the SBR phase, but it is also distributed in the IR phase when the IR fraction in the total rubber components is higher than 40 wt%. The preferential distribution of silica in the SBR phase improves the dispersion of the IR domains. This is the first use of this technique for a multicomponent polymer system, showing the advantage to characterize the complicated multicomponent polymer composite morphologies.  相似文献   
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聚丙烯性能试验方法对比研究   总被引:1,自引:0,他引:1  
选择均聚聚丙烯(PP—H)、抗冲共聚聚丙烯(PP—B)、无规共聚聚丙烯(PP—R)共7个牌号的聚丙烯(PP)产品为研究对象,对比研究了国际标准化组织(简称ISO)制定的标准和美国材料试验协会(简称ASTM)制定的标准对三类PP性能测试的影响。ISO和ASTM2种标准测得的PP产品的拉伸性能、弯曲性能、缺口冲击强度和负荷变形温度存在一定的差异。但2种标准的测试结果具有一定的规律性,这些规律可为今后修订聚丙烯行业和企业标准提供参考。  相似文献   
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