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目的 评价石杉碱甲片联合丁苯酞软胶囊对阿尔茨海默病患者认知功能的临床疗效.方法 将100例轻度阿尔茨海默病(Alzheimer's disease,AD)患者随机分为石杉碱甲片联合丁苯酞软胶囊组(治疗组)及单独应用石杉碱甲组(对照组).治疗前及治疗90 d后分别评价两组患者简易智力状态检查(Mini-mental State Examination,MMSE)量表、事件诱发电位P300潜伏期、波幅及不良反应.结果 石杉碱甲片联合丁苯酞软胶囊组治疗90 d后,MMSE评分和P300潜伏期、波幅与治疗前比较差异均具有统计学意义(P<0.05);与单独应用石杉碱甲组比较差异具有统计学意义(P<0.05).结论 石杉碱甲片联合丁苯酞软胶囊对轻度阿尔茨海默病患者认知功能有明显改善,且优于单独应用石杉碱甲片组. 相似文献
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为了在保证较高水平的保障可用度前提下提高舰载机出动效率, 提出一种支持可用度约束的统计优化模型及其对应的启发式求解算法。能够同时生成舰载机的保障作业调度方案和保障装备计划性维护的时间安排, 并通过基于仿真的优化方式, 在启发算法的适应度评价中增加对视情维修和事后维修的仿真, 提高了舰载机作业调度方案的鲁棒性。仿真结果表明,所提算法能够提供一个稳定可靠的基准调度方案, 避免不必要的重调度。 相似文献
4.
Patricio Atanes Inmaculada Ruz-Maldonado Ross Hawkes Bo Liu Min Zhao Guo Cai Huang Israa Mohammed Al-Amily Albert Salehi Stefan Amisten Shanta J. Persaud 《Cellular and molecular life sciences : CMLS》2018,75(16):3039-3050
Introduction
Islets synthesise and secrete numerous peptides, some of which are known to be important regulators of islet function and glucose homeostasis. In this study, we quantified mRNAs encoding all peptide ligands of islet G protein-coupled receptors (GPCRs) in isolated human and mouse islets and carried out in vitro islet hormone secretion studies to provide functional confirmation for the species-specific role of peptide YY (PYY) in mouse islets.Materials and methods
GPCR peptide ligand mRNAs in human and mouse islets were quantified by quantitative real-time PCR relative to the reference genes ACTB, GAPDH, PPIA, TBP and TFRC. The pathways connecting GPCR peptide ligands with their receptors were identified by manual searches in the PubMed, IUPHAR and Ingenuity databases. Distribution of PYY protein in mouse and human islets was determined by immunohistochemistry. Insulin, glucagon and somatostatin secretion from islets was measured by radioimmunoassay.Results
We have quantified GPCR peptide ligand mRNA expression in human and mouse islets and created specific signalomes mapping the pathways by which islet peptide ligands regulate human and mouse GPCR signalling. We also identified species-specific islet expression of several GPCR ligands. In particular, PYY mRNA levels were ~ 40,000-fold higher in mouse than human islets, suggesting a more important role of locally secreted Pyy in mouse islets. This was confirmed by IHC and functional experiments measuring insulin, glucagon and somatostatin secretion.Discussion
The detailed human and mouse islet GPCR peptide ligand atlases will allow accurate translation of mouse islet functional studies for the identification of GPCR/peptide signalling pathways relevant for human physiology, which may lead to novel treatment modalities of diabetes and metabolic disease.5.
In this paper, PID (proportional-integral-derivative) controllers will be designed to solve the tracking problem for a class of coupled multi-agent systems, where each agent is described by a second-order high-dimensional nonlinear uncertain dynamical system, which only has access to its own tracking error information and does not need to communicate with others. This paper will show that a 3-dimensional manifold can be constructed based on the information about the Lipschitz constants of the system nonlinear dynamics, such that whenever the three parameters of each PID controller are chosen from the manifold, the whole multi-agent system can be stabilized globally and the tracking error of each agent approaches to zero asymptotically. For a class of coupled first-order multi-agent nonlinear uncertain systems, a PI controller will be designed to stabilize the whole system. 相似文献
6.
The lack of continuous connectivity and a complete path from source to destination makes node communication quite difficult in Delay-Tolerant Networks(DTNs). Most studies focus on routing problems in idealized network environments without considering social properties. Communication devices are carried by individuals in many DTNs; therefore, DTNs are unique social networks to some extent. To design efficient routing protocols for DTNs, it is important to analyze their social properties. In this paper, a more accurate and comprehensive metric for detecting the quality of the relationships between nodes is proposed, by considering the contact time, contact frequency, and contact regularity. An overlapping hierarchical community detection method is designed based on this new metric, and a tree structure is built. Furthermore, we exploit the overlapping community structure and the tree structure to provide message-forwarding paths from the source node to the destination node.The simulation results show that our Routing method based on Overlapping hierarchical Community Detection(ROCD) achieves better delivery rate than SimBet and Bubble Rap, the classic routing protocols, without affecting the average delay. 相似文献
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随着物联网技术飞速发展,租赁设备大多安装有传感系统,可以及时地对设备关键部件和整体运行状态进行检测,进而可基于设备的健康状态为其安排更为合理的维修方案,在降低租赁商维修费用的同时,尽量少地干预客户的正常施工,并且保证租赁设备在客户施工场所的可靠运行.本文研究了基于状态检测的租赁设备的最优维修问题,研究中引入了顺序状态检测,定义了基于状态的控制限维修策略,并建立了以维修开销最小为目标的解析模型,以决策系统最优的检测间隔和预防维修阈值.除检测、维修等基本费用外,模型中还进一步考虑了租赁系统的故障罚金和故障后维修超时罚金.在模型的求解中,推导了维修干预下设备任意时刻的检测概率和状态概率分布,作为模型构建和求解的依据.数值实验结果验证并表明了面向租赁设备的基于状态的维修策略的有效性. 相似文献
8.
通过室温拉伸测试和显微组织观察,研究了挤压温度和热处理工艺对Ti-1300钛合金挤压管材显微组织和力学性能的影响,讨论了热加工工艺、显微组织和力学性能之间的关系。结果表明:Ti-1300钛合金在两相区挤压后的横向组织均匀细小,纵向组织沿挤压加工流线破碎均匀;其拉伸强度高达1 445 MPa。管材在相变点以上的高温固溶组织主要由等轴β相晶粒组成,具有较好的塑性。合金两相区挤压后具有较好的强度和塑性的匹配,两相区挤压的塑性明显优于β单相区挤压,尤其面缩。试样经过固溶时效处理后显微组织明显细化,强度大幅度提高,可达1 300 MPa以上。 相似文献
9.
以市场中9种饮料为研究对象,探究阿斯巴甜含量测定方法.实验结果表明:流动相39%的甲醇水溶液,柱温30℃、流速0.8mL/min时,在210nm波长处存在阿斯巴甜的最大吸收峰,1-9号样品阿斯巴甜含量依次为:0.164mg/kg、0.079mg/kg、0.202mg/kg、0.00mg/kg、0.029mg/kg、0.043mg/kg、0.121mg/kg、0.063mg/kg、0.053mg/kg.实验精密度RSD值为1.233%、稳定性RSD值为0.395%、平均加标回收率为100.3%.研究为食品中阿斯巴甜含量检测提供理论参考. 相似文献
10.
文章利用方志与墓志中的商业与商人史料,分析了明清时代鄱阳县本地商业状况与外来商帮构成,以及鄱阳商人的经营行业和商贸地域.透过商人的传记资料,可以看到士人为商人写传,大力肯定商人的志业,商人则高度认同士人所代表的儒学主流价值观;方志为商人立传,商人为桑梓与国家效力,体现的是士商之间、商人与国家和社会之间相得益彰、"美美与共"的良性互动. 相似文献