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641.
Objective To investigate changes in T lymphocyte subsets and NK cells in patients with simple Graves' disease (GD)and Graves' disease combined with type 2 diabetes mellitus (GD/T2DM). Methods Fifteen cases of GD/ T2DM were selected from our hospital from November 2001 to November 2004. Before and after therapy thyroid function, thyroglobulin antibody (TGA), thyroid microsomal antibody (TMA) and blood glucose level were measured, and T lymphocyte subsets (CD3, CD4, CD8, CD4/CD8) and NK cells (CD56) were measured by immunofluorescence double labeling monoclonal antibody and flow cytometry, respectively. At the same time, comparison was made with simple GD (15 cases), T2DM (15 cases) and healthy control (20 cases). Results Before therapy, CD4/CD8, CD4 and NK cells in GD/T2DM were less than normal, and there was no significant difference in comparison with simple GD (P<0.05). In T2DM group, only CD4/CD8 and CD4 were less than those of healthy controls (P<0.05). When thyroid function recovered after 1 to 3 months of methimazole treatment in both GD/T2DM and simple GD groups, various indexes recovered, which were more obvious in simple GD. Conclusion Immune hypofunction of GD may be the key to the immune abnormality of GD/T2DM, which is more significant than that of simple GD or T2DM. The recovery of thyroid function and immune abnormality is not consistent, and the recovery of GD is more significant than that of GD/T2DM.  相似文献   
642.
在100℃,6mol/L的硫酸作用下,含硬质粗蛋白很高的羽肠粉经10h水解可制得氨基酸态氮含量为5.2mg/mL的氨基酸。其水解液 的酸可用氧化钙中和至微酸性。过滤后的滤液经稀释做为农作物叶面喷施的有机液体肥,而剩余的滤渣亦可做缺硫土壤用的固体肥料。  相似文献   
643.
介绍武广高速铁路移动通信公网的建设及通信效果,给乘客提供通信无缝连接、优质、可靠的通信服务,并希望对其他铁路工程建设有所参考。  相似文献   
644.
从上世纪90年代早期到目前为止,尼日利亚联邦政府并没对航运业和造船修理业投入太多精力。一个典型例子就是,由于对这些行业不够重视导致了前尼日利亚国家货运公司(NNSL)的衰败及倒闭。1996年,尼日利亚联合货运公司(NUL)成立。但新公司的成立并  相似文献   
645.
舰船电力系统保护性能优化的自适应算法   总被引:1,自引:0,他引:1  
为满足舰船电力系统保护在快速性和选择性方面的要求,提出保护性能优化模型,根据电力系统的运行方式、拓扑结构和故障类型的变化,实时在线计算并修改保护整定值的自适应保护方法。将快速性和选择性指标作为保护性能综合指标的基本元素,采用模拟退火粒子群算法进行优化,最终实现不同运行工况下保护性能最优的整定值自适应调整。并在PSCAD/EMTDC软件中建立包含自适应保护算法的舰船电力系统保护仿真模型,仿真结果证明所提方法可有效提高系统保护性能。  相似文献   
646.
Within the literature concerned with aspects of competitiveness, innovation and strategic management of industrial clusters, the body regarding forecasting of strategic management is still nascent. This work aspires to render a contribution within the domain of strategic management forecasting, through the indicative case of European maritime clusters. For this end, a two-tier model is formulated. A quantitative strengths, weaknesses, opportunities, and threats (SWOT) methodology that derives from the fusion of a quondam situation analysis and crosstabs’ theory is generated. This leads to the utilization of the crosstab’s conditional probabilities as transition probabilities; the latter are called to compile the transition matrix of a Markov chain. Through this methodology, and the successive Markov chain’s transition matrices, strategic forecasts are extracted for a devised European maritime cluster case. This work relinquishes a novel application with respect to strategic management forecasting, that provides a dichotomy of practical interpretations and scenarios for quantitative situation analysis. Thus, it may enable effective real-time decision-making for strategic management and/or policy drafting. The situation analysis forecasting model may find applicability in a plethora of practical and theoretical cases, wherein forecasting may be desirable. It may as well pertain to an intrinsic methodology for situation analysis forecasting of maritime clusters.  相似文献   
647.
Understanding how people are dependent on Large Scale Marine Protected Areas (LSMPAs) is important for understanding how people might be sensitive to changes that affect these seascapes. We review how resource dependency is conceptualized and propose that it be broadened to include cultural values such as pride in resource status, scientific heritage, appreciation of aesthetics, biodiversity, and lifestyle opportunities. We provide an overview of how local residents (n = 3,181 face-to-face surveys), commercial fishers (n = 210, telephone surveys), and tourism operators (n = 119 telephone surveys) are potentially dependent on the Great Barrier Reef (GBR), a region currently experiencing significant environmental, social, and economic change. We found that commercial fishers and tourism operators were dependent not only financially on the GBR, but also because of their age, years in the industry and region, lack of education, and the number of dependents. These stakeholders lacked flexibility to secure alternative employment. All stakeholder groups, regardless of economic imperatives, were dependent on the GBR because of their cultural connections. We propose that resource dependency also provides an umbrella concept to describe the cultural services provided by an ecosystem, which can be described through place-based dependence and place-identity.  相似文献   
648.
动态电压恢复器(DVR)可在供电电压发生电压下陷时维持负载电压稳定,以保护敏感负载。由于在正常电力系统中,电压下陷故障出现的频率相对不高,使得DVR的利用率较低。将一种基于二阶开关平面理论的边界控制器应用于DVR系统,使其既可用于电压下陷补偿又能用于稳态下电压电能质量控制,大大提高了设备利用率。通过预测DVR逆变器的某次开关动作后,其系统状态矢量的运动轨迹可得到上述二阶开关平面。将该平面作为状态轨迹沿理想开关平面运动的上界,可约束轨迹使其趋向理想工作点。为考察其动态特性,应用上述控制器的DVR样机针对源端谐波畸变和伴有畸变的下陷电压波形进行了补偿试验。结果证实上述边界控制方案可获得优于其它一些控制策略的谐波补偿效果。  相似文献   
649.
This paper examines a case study of the SkyCabs system as a way to alleviate some of the traffic problems of Auckland, New Zealand. SkyCabs is an elevated two-way monobeam carrying light eight-seater cabs on tracks on each side of the beam, available on demand, providing fast, pollution-free, unimpeded travel above the footpath with panoramic views of the city. The aim of this study is to investigate the attractiveness of implementing the SkyCabs system to and from Auckland central business district (CBD) and Auckland international airport by examining four variables: different routes, different number of stops/stations, different passenger demand levels, and different number of cabs in the system. The analysis utilizes geographical information system and simulation tools for the various scenarios considered. The results show that it is possible to assess the cost–benefit of alternative routes in terms of those four variables and rate of return on investment.  相似文献   
650.
In this paper, a new cellular automata model is proposed to simulate the car and bicycle heterogeneous traffic on urban road. To capture the complex interactions between these two types of vehicles, a novel occupancy rule is adopted in the proposed model to consider the variable lateral distances of mixed vehicular traffic. Based on massive simulations, microscopic fundamental diagrams under different bicycle densities are devised. With these, the bicycle's spilling behavior is then investigated and discussed. In order to reflect the interference of a bicycle on a car, the interference transformation from friction state to block state is modeled explicitly. Finally, different simulation results under different occupancy rules indicate that the constant and fixed occupancy rule adopted in the previous studies might lead to overestimation of car flux in the heterogeneous traffic flows with different bicycle densities. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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