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81.
82.
A transparent wound dressing sheet was obtained by forming a complex between β-glucan and chitosan (CS). These materials were chosen for their biocompatible, bioabsorbable, and biodegradable properties, and they were expected to promote the therapeutic efficacy of the dressing by increasing the wound healing response. The therapeutic efficacy of the β-glucan–CS complex sheet as a wound dressing was evaluated in wounds created on the dorsal surfaces of mice. β-glucan–CS complex sheets demonstrated therapeutic efficacies comparable or superior to that of Beschitin®W, a commercial wound dressing made from CS. Additionally, the β-glucan–CS complex sheet did not dissolve during the application period, did not adhere to wounds, and was easy to remove. Cumulatively, these results indicate that β-glucan–CS complex sheets are a promising new wound dressing product.  相似文献   
83.
针对雷击故障参考点定位不准确,导致测距结果可能与雷击故障发生的实际距离相差较大的问题,结合雷电记录与行波数据,从雷击故障参考点定位角度着手,进行雷击故障测距结果优化研究。首先获取相关雷电记录和行波数据,然后计算待分析故障特征点,并利用雷击故障历史数据、非雷击故障历史数据、雷电定位系统历史数据,构建(Δx,Δt,ΔP)三维坐标系,划分雷击故障识别域和非雷击故障识别域,判断待分析故障特征点是否落入雷击故障识别域当中,确定雷击故障参考点,最后利用行波测距方法得出雷击故障精确位置。结果表明,与基于雷电记录或基于行波数据的2种单一测距方法相比,该方法测距结果更接近实际值,由此可知,雷击故障测距结果得到优化,提高了测距精度。  相似文献   
84.
We have studied the effect of enhanced oxygen delivery by perfluorocarbons on the differentiation of C2C12 cells. The extent of differentiation was assessed by means of phase contrast/fluorescence microscopy, active tension measurement and the glucose consumption/lactate production rates. We found that enhanced oxygen delivery is suitable for full differentiation of C2C12 cells.  相似文献   
85.
文章借助当前医院的"OA"院内办公系统,构建医务人员对医技科室工作评价平台,通过该平台,嵌入医院医技科室服务调查问卷的web页面,再通过数据挖掘技术即可实现对医院医技科室的评价,从HCS随访系统内医院也可直观的查看各医技科室的满意度调查结果统计,具有很强的实用性,并大幅提高医院工作效率。  相似文献   
86.
The thermal conductivity of the surface layer of engineering materials changes in the early stages of material degradation due to the appearance of micro‐cracks. A new method for evaluating and assessing the degree of degradation of a material using this change is proposed herein. The influence of the micro‐cracked layer on the temperature response as measured by a thermophysical handy tester was theoretically examined. By defining a thermal degradation parameter, the amount of degradation of various materials was evaluated. In order to verify this theory, fatigue tests using metallic materials were conducted. Comparisons before and after the fatigue tests were then made to establish the correlation between the density of micro‐cracks and the decrease in thermal conductivity. As a result, it was ascertained that a thermal degradation parameter can easily be estimated from a temperature response curve obtained using the tester. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(8): 501–512, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20178  相似文献   
87.
The Tetrahymena Ca(2+)-binding protein of 25 kDa (TCBP-25) is a member of the calmodulin family containing four EF-hand Ca(2+)-binding loops, but its biological role has not yet been investigated. In this study, TCBP-25 was expressed in Escherichia coli as a glutathione S-transferase fusion protein and then purified. Purified TCBP-25 showed a typical Ca(2+)-dependent shift in electrophoretic mobility, consistent with conformational change caused by Ca(2+)-binding. Localization of TCBP-25 was examined by indirect immunofluorescence using an antiserum specific for TCBP-25. Strong immunofluorescence was observed all over the cell cortex except in and around basal bodies. From the results of immunofluorescence using detergent-extracted cells, TCBP-25 is suggested to exist as an insoluble form in the cell cortex. TCBP-25 appears to be localized in the cortical alveoli or the epiplasm and exists around both the migratory and the stationary gametic pronuclei at the pronuclear exchange stage during conjugation. Therefore, we speculate that TCBP-25 may play crucial roles in Ca(2+)-mediated signaling processes in the cell cortex and in a Ca(2+)-dependent pronuclear exchange process during conjugation.  相似文献   
88.
日本新建筑标准的结构抗火设计   总被引:4,自引:0,他引:4  
本的目的是为了说明1998—2000期间日本建筑规程(日本建筑标准)以及相关技术标准的修订。考虑了功能要求后,规程修订趋向于以性能为主。在抗大这一章节中,功能要求指的是在发生火灾时防止结构倒塌以及火势向其他隔问的蔓延,同时还包括防止火势由失火建筑物内部向周围建筑的扩散。为了满足功能上的要求,我们提供了三种方法(A、B、C)。方法A是传统的设计方法,即建筑框架及隔墙采用防火构件。相对于方法A,新近引进了以考虑性能为主的方法B。在方法B中,由一系列设计公式计算出指定部分发生火灾可能产生的后果、结构和边界部分的热反应、构件破坏的临界时间。设计公式应足够简单,以便于建筑工程师和有关官员的使用。由方法B计算出的结果通常是保守的。方法C是一个框架,用最先进的设计方法。规程没有指定采用的设计方法,但是工程上火灾和结构分析的结果只有在全面地考证后才能被行业接受。  相似文献   
89.
The optimum BISDN teleconference service for business, called hypermedia teleconference, is designed based on research into typical business activities and ATM, the most promising BISDN architecture. Service characteristics are determined by analysing the daily work practices of a large set of businessmen. It is shown that communication tasks occupy 44 per cent of the working day. The analysis further shows that some 60 per cent of all communication tasks could be performed through an advanced digital teleconference service. Hypermedia teleconference is designed to satisfy the needs of business through personal communication terminals and ATM public networks. The terminals effectively allocate the BISDN's high-speed transmission capability between a number of subchannels that realize distributed multipoint connection links and multimedia paths. The terminals use a new variable-bit-rate ATM codec created to realize high quality video. Users can easily create full featured teleconferences without a centralized connection facility. Terminals allow the synergistic combination of video, voice, telewriting, telepointing and document transmission services.  相似文献   
90.
详述了单一纳米(非)金属粉和纳米复合(非)金属粉在固体推进剂应用中的发展现状,重点介绍了纳米铝粉存在的问题及解决方法。概述了纳米铝热剂、纳米(非)金属粉/碳纳米管、纳米(非)金属粉/石墨烯等功能化纳米(非)金属粉在固体推进剂中的研究进展。分析了纳米(非)金属粉发展中的瓶颈,并指出了未来发展方向,为该领域科研人员进一步研究高活性纳米(非)金属粉提供相应的参考。  相似文献   
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