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81.
Habib M Hussain I Fang WH Rajput ZI Yang ZZ Irshad H 《Journal of Zhejiang University. Science. B》2006,7(4):320-323
In this experiment conducted to study the inactivation dynamics of infectious bursal disease virus (IBDV) by binary ethylenimine (BEI) in comparison with formalin, IBDV was isolated from the bursa of infected chickens and its confirmation was done by agar gel precipitation test. Viral suspensions were subjected to inactivation with BEI and formalin for pre-set time in- tervals. BEI was employed at concentrations of 0.001 and 0.002 mol/L while formalin was used at 0.1% and 0.2%. Sampling was done at 6, 12, 24, 36 and 48 h of incubation and samples were tested for their inactivation status in 9-day-old embryonated eggs and 3-week-old broiler chickens. IBDV was completely inactivated by 0.001 and 0.002 mol/L BEI after 36 h of incubation at 37℃, whereas formalin at 0. 1% and 0.2% concentrations inactivated IBDV in 24 h. 相似文献
82.
针对水泥混凝土路面的主要病害和机理,探讨选择基层材料的合理性及其施工方法,以减少水泥混凝土路面的施工病害。 相似文献
83.
标准粒子群算法(PSO)容易陷入局部最优解,导致收敛速度慢、效率低.文章结合遗传算法提出了改进的组合粒子群算法,在每次迭代后应用随机函数随机选择下一次迭代所使用的变异策略或交叉策略.由测试数据表明组合粒子群算法在求解TSP时性能上有很大提高. 相似文献
84.
ABSTRACTThis study operationalized Weick’s [(1988). Enacted sensemaking in crisis situations. Journal of Management Studies 25(4), 305–317 and (1993). The collapse of sensemaking in organizations: The Mann Gulch disaster. Administrative Science Quarterly, 38, 628–652] theory of enacted sensemaking to examine the communication processes associated with the Flint Water Crisis of 2014–2015. A content analysis of 389 emails and attachments from a total population of N?=?37,376 pages of publicly released e-mails and documents pertaining to Flint’s water issues, identified examples of failed sensemaking by government officials. These failures hastened and intensified a growing crisis of lead contamination and an outbreak of Legionnaires disease associated with Flint’s municipal water system. Analysis of email messages suggests that strong commitments by top leaders and limited capacity were important factors as were efforts to create and maintain consensus among officials. The Flint Water Crisis offers an important application of sensemaking theory and its utility for both organizational and risk communication scholars and for practical application. The authors emphasize the importance of questioning previous assumptions and commitments, insuring that communication practitioners are involved in decisions, and avoiding over reliance on image repair as a strategic response. 相似文献
85.
Xiaochuan Zhang Xianzhen Yin Jingjing Zhang Anan Li Hui Gong Qingming Luo Haiyan Zhang Zhaobing Gao Hualiang Jiang 《国家科学评论(英文版)》2019,6(6):1223
Accumulating evidence indicates the critical importance of cerebrovascular dysfunction in the pathogenesis of Alzheimer''s disease (AD). However, systematic comparative studies on the precise brain vasculature of wild-type and AD model mice are still rare. Using an image-optimization method for analysing Micro-Optical Sectioning Tomography (MOST) data, we generated cross-scale whole-brain 3D atlases that cover the entire vascular system from large vessels down to smallest capillaries at submicron resolution, for both wild-type mice and a transgenic (APP/PS1) mouse model of AD. In addition to distinct vascular patterns in different brain regions, we found that the main vessels of the molecular layer of the hippocampal dentate gyrus (DG-ml) undergo abrupt changes in both diameter and branch angle, spreading a unique comb-like pattern of capillaries. By using a quantitative analysis workflow, we identified in the hippocampus of AD mice an overall reduction of the mean vascular diameter, volume fraction and branch angle, with most significant impairment in the DG-ml. In addition, virtual endoscopy revealed irregular morphological features in the vessel lumen of the AD mice, potentially contributing to the impairment of blood flow. Our results demonstrate the capability of high-resolution cross-scale evaluation of brain vasculature and underscore the importance of studying hippocampal microcirculation for understanding AD pathogenesis. 相似文献
86.
刘丽娟 《中华医学图书馆杂志》2008,17(2):47-49
近年来,有关阿尔茨海默病的文献大量涌现,但《中图法》第4版中并无相关类目。通过对《中图法》R749.16老年及早老性精神障碍和中国精神疾病分类的分析,参照国际疾病分类(ICD-10)和《美国精神疾病诊断与统计手册》第4版修订本(DSM-IV-R)和《中国精神障碍分类与诊断标准》第3版(CCMD-3)相关类目的现行标准和原则,提出3种分类方案。 相似文献
87.
系统深入地研究了光谱与色谱方法用于有机合成分析,本文依据光谱与色谱方法发现传统合成过程中金属卟啉相互转化问题,并进行了深入探讨,从而改进了合成方法,取得良好结果。 相似文献
88.
离散型随机变量的数学期望在法律、医学和经济等问题中的应用 总被引:1,自引:0,他引:1
陈卫东 《广东广播电视大学学报》2005,14(4):103-105
数学期望是随机变量的重要的数字特征之一。本文通过民事纠纷、疾病普查和利润的例子探讨离散型随机变量的数学期望在法律、医学和经济等问题的应用。 相似文献
89.
从神经生理谈老年性痴呆症的发病机制与疗法 总被引:2,自引:0,他引:2
从神经生理的角度分析了老年痴呆症的发病机制,认为老年痴呆与胆碱能、单胺能、神经肽能等多种递质和调制物的功能障碍有着直接的联系,提出了根据病因采用中药、西药和康复3大类的治疗方法。 相似文献
90.
用昆明种小白鼠对中药复方制剂"连黄"进行了传统致畸试验与致突变试验.结果表明,在传统致畸试验中,对孕鼠的着床数、死胎数、吸收胎数等进行了检查,与对照组比较差异不显著(P>0.05);致突变试验结果表明,小白鼠的微核、精子畸形呈阴性反应,Ames试验也呈阴性反应;结论,中药制剂"连黄"对小鼠无致畸和致突变作用. 相似文献