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101.
We report a genome-wide association study for open-angle glaucoma (OAG) blindness using a discovery cohort of 590 individuals with severe visual field loss (cases) and 3,956 controls. We identified associated loci at TMCO1 (rs4656461[G] odds ratio (OR) = 1.68, P = 6.1 × 10(-10)) and CDKN2B-AS1 (rs4977756[A] OR = 1.50, P = 4.7 × 10(-9)). We replicated these associations in an independent cohort of cases with advanced OAG (rs4656461 P = 0.010; rs4977756 P = 0.042) and two additional cohorts of less severe OAG (rs4656461 combined discovery and replication P = 6.00 × 10(-14), OR = 1.51, 95% CI 1.35-1.68; rs4977756 combined P = 1.35 × 10(-14), OR = 1.39, 95% CI 1.28-1.51). We show retinal expression of genes at both loci in human ocular tissues. We also show that CDKN2A and CDKN2B are upregulated in the retina of a rat model of glaucoma.  相似文献   
102.
电刺激小脑顶核对大鼠心肌梗死后心脏神经再生的影响   总被引:3,自引:0,他引:3  
探讨预先电刺激小脑顶核(FNS)对大鼠心肌梗死(MI)后心脏神经再生的干预作用。将90只Wistar大鼠随机分为:①MI组,结扎左冠状动脉前降支(LAD);②预先电刺激小脑顶核后再予以LAD结扎组(FNS MI组);③毁损小脑顶核后电刺激该部位,再行LAD结扎组(FNL FNS MI组)。各组又分MI后1,7,21d3个时间点。另设假手术组(Sham组)。应用免疫组织化学方法显示心脏组织胆碱乙酰转移酶(CHAT)和酪氨酸羟化酶(TH)。检测各时间点梗死区与非梗死区TH、CHAT阳性神经纤维分布密度,MI组与Sham组相比显著减少(P<0.01);FNS MI组较MI组显著增多(P<0.05);FNL FNS MI组与MI组比较无显著性差异(P>0.05)。因此,电刺激小脑顶核可增加梗死区和非梗死区心肌组织TH、CHAT染色阳性神经纤维密度,促进MI后心脏神经纤维再生。  相似文献   
103.
104.
Railway transportation plays an important role in modern society. As China's massive railway transportation network continues to grow in total mileage and operation density, the energy consumption of trains becomes a serious concern. For any given route, the geographic characteristics are known a priori, but the parameters(e.g., loading and marshaling) of trains vary from one trip to another. An extensive analysis of the train operation data suggests that the control gear operation of trains is the most important factor that affects the energy consumption. Such an observation determines that the problem of energy-efficient train driving has to be addressed by considering both the geographic information and the trip parameters. However, the problem is difficult to solve due to its high dimension, nonlinearity, complex constraints, and time-varying characteristics. Faced with these difficulties, we propose an energy-efficient train control framework based on a hierarchical ensemble learning approach. Through hierarchical refinement, we learn prediction models of speed and gear. The learned models can be used to derive optimized driving operations under real-time requirements. This study uses random forest and bagging – REPTree as classification algorithm and regression algorithm, respectively. We conduct an extensive study on the potential of bagging, decision trees, random forest, and feature selection to design an effective hierarchical ensemble learning framework. The proposed framework was testified through simulation. The average energy consumption of the proposed method is over 7% lower than that of human drivers.  相似文献   
105.
Amidst the rapid development of the Internet of Things(IoT), Vehicular Ad-Hoc NETwork(VANET), a typical IoT application, are bringing an ever-larger number of intelligent and convenient services to the daily lives of individuals. However, there remain challenges for VANETs in preserving privacy and security. In this paper, we propose the first lattice-based Double-Authentication-Preventing Ring Signature(DAPRS) and adopt it to propose a novel privacy-preserving authentication scheme for VANETs, offering the potential for security against quantum computers. The new construction is proven secure against chosen message attacks. Our scheme is more efficient than other ring signature in terms of the time cost of the message signing phase and verification phase, and also in terms of signature length. Analyses of security and efficiency demonstrate that our proposed scheme is provably secure and efficient in the application.  相似文献   
106.
接触辉光放电等离子体降解水体中硝基苯   总被引:11,自引:0,他引:11  
用接触辉光放电等离子体对硝基苯的降解进行了研究,考查了电压、浓度、pH值、催化剂对降解率的影响。结果表明:电压、浓度、催化剂对反应速率有显著影响,pH对硝基苯降解无明显影响。同时,利用高效液相色谱法对中间产物进行了分析,推测了硝基苯接触辉光放电降解的历程。  相似文献   
107.
应用CNDO/2方法研究了二氯二聚吡咯合铁配合物(DCBPF)的结构和H2在该配合物上的吸附行为,确定了配合物的稳定结构,讨论了被吸附分子相对于配合物的不同吸附取向的影响,优化了各个体系相对于能量的分子间距,探究了吸附的微观机制,得到了一些比较有意义的结果。  相似文献   
108.
高职<公路工程计量与计价>是一门技术性、实践性很强的课程.高职教育特别强调面向工作岗位适岗能力的培养,所以必须以学生就业岗位的工作内容为出发点,以岗位能力培养为目标构建课程内容体系.文章提出的四情境、四步骤教学内容体系,打破了传统的教学体系束缚,把知识和能力融入具体工作岗位项目的实施过程中,突出培养学生分析、解决实际工程问题的能力,实现课程和就业岗位零距离对接.  相似文献   
109.
通过对血浆标本的核酸和血清学检测结果进行比较分析,探讨核酸检测(NAT)与酶联免疫吸附试验(ELISA)联合应用在血液筛查中的意义.研究从血浆样本中同时提取HBV、HIV和HCV核酸,采用荧光实时聚合酶链反应(PCR)进行检测,同步进行ELISA检测HBV、HIV和HCV抗原或抗体.在5 184份血浆标本中检测出HBV“窗口期”标本12份,检出率为0.23%;检测出HCV“窗口期”标本3份,检出率为0.058%;未检测出HIV“窗口期”标本.从而得出结论,核酸检测可以有效检测出血浆中的HBV、HIV和HCV的“窗口期”标本.  相似文献   
110.
Ecological compensation is becoming one of key and multidiscipline issues in the field of resources and environmental management. Considering the change relation between gross domestic product (GDP) and ecological capital (EC) based on remote sensing estimation, we construct a new quantitative estimate model for ecological compensation, using county as study unit, and determine standard value so as to evaluate ecological compensation from 2001 to 2004 in Zhejiang Province, China. Spatial differences of the ecological compensation were significant among all the counties or districts. This model fills up the gap in the field of quantitative evaluation of regional ecological compensation and provides a feasible way to reconcile the conflicts among benefits in the economic, social, and ecological sectors.  相似文献   
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