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False Positive HIV “Combo” Screening Test in a Hemodialysis Patient in Saudi Arabia: A Case Report and Review of the Literature
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作者 Ngozi Virginia Aikpokpo Ahmed Yayha Omaysh 《Case Reports in Clinical Medicine》 2024年第9期366-374,共9页
Introduction: HIV screening tests are routinely conducted on dialysis patients as the constant exposure of their blood during the dialysis process makes them a reasonable risk for blood-borne infections. However, in l... Introduction: HIV screening tests are routinely conducted on dialysis patients as the constant exposure of their blood during the dialysis process makes them a reasonable risk for blood-borne infections. However, in low prevalence settings, where HIV rates are <0.1% of the population, false positive results are more likely. This results in apprehension in the dialysis unit as breaches in infectious disease protocols could be presumed. This is illustrated in the case report below. Case Summary: A 62-year-old male Saudi end-stage kidney disease patient secondary to DM nephropathy began dialysis a year before presentation in a hemodialysis center in Saudi Arabia. Routine screening tests done at the start of dialysis revealed negative Hepatitis C, HIV 1 and 2 screening but a positive Hepatitis B surface antigen screen. The patient went for holiday dialysis at another facility and had a routine fourth-generation HIV test done which was positive. A confirmatory HIV PCR test was negative. Conclusion: This case highlights the need for caution in interpreting highly sensitive and specific HIV screening tests in a low-prevalence setting. Routine screening beyond the national recommendation may not be necessary in low-prevalence areas. 展开更多
关键词 Saudi Arabia False Positive HIV test HEMODIALYSIS
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紧急切断阀部分行程测试功能的实现方式与适用性分析
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作者 李俊 《石油化工自动化》 CAS 2024年第5期57-63,共7页
随着石油化工行业安全意识的不断增强,针对一些重大风险源的联锁评估的要求也不断提高,在项目SIL验证阶段出现结果不满足SIL定级要求的情况时有发生。为避免增加类似以降低SIL评估等级为目标的额外独立保护层的高成本方案,提出了紧急切... 随着石油化工行业安全意识的不断增强,针对一些重大风险源的联锁评估的要求也不断提高,在项目SIL验证阶段出现结果不满足SIL定级要求的情况时有发生。为避免增加类似以降低SIL评估等级为目标的额外独立保护层的高成本方案,提出了紧急切断阀部分行程测试作为一种缩短检测周期、提高检测覆盖率的有效手段。介绍了紧急切断部分行程测试功能的由来以及其具体要求,列举了不同形式的实现方式以及现有的一些产品,并在实际应用层面进行了详细分析,并从经济性、可用性、安全性等方面进行了全面比较,推荐了成本适中、适用性最广的气路设计类的测试解决方案。 展开更多
关键词 紧急切断阀 部分行程测试 机械限位 PST专用执行机构 ESD阀门定位器
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CT colonography after incomplete colonoscopy in subjects with positive faecal occult blood test 被引量:1
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作者 Lapo Sali Massimo Falchini +7 位作者 Andrea Giovanni Bonanomi Guido Castiglione Stefano Ciatto Paola Mantellini Francesco Mungai Ilario Menchi Natale Villari Mario Mascalchi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第28期4499-4504,共6页
AIM: To report our experience with computed tomography colonography (CTC) systematically performed in subjects with positive faecal occult blood test (FOBT) and an incomplete colonoscopy in the setting of a popul... AIM: To report our experience with computed tomography colonography (CTC) systematically performed in subjects with positive faecal occult blood test (FOBT) and an incomplete colonoscopy in the setting of a population-based screening for colorectal cancer (CRC). METHODS: From April 2006 to April 2007, 43 290 individuals (age range 50-70) who adhered to the regional screening program for the prevention of CRC underwent immunochemical FOBT. FOBT was positive in 1882 subjects (4.3%). 1463 (77.7%) of these subjects underwent colonoscopy, 903 performed in a single center. Of 903 colonoscopies 65 (7.2%) were incomplete. Forty-two of these subjects underwent CTC. CTC was performed with a 16-MDCT scanner after standard bowel prep (polyethyleneglycole) in both supine and prone position. Subjects whose CTC showed polyps or masses were referred to the endoscopist for repeat colonoscopy under sedation or underwent surgery. Perlesion and per-segment positive predictive values (PPV) were calculated. RESULTS: Twenty-one (50%) of 42 CTCs showed polyps or masses. Fifty-five of these subjects underwent a repeat colonoscopy, whereas 2 subjects underwent surgery for colonic masses of indeterminate nature. Four subjects refused further examinations. CTC correctly identified 2 colonic masses and 20 polyps. PPV for masses or polyps greater than 9 mm was of 87.5%. Per-lesion and per-segment PPV were, respectively, 83.3% and 83.3% for polyps greater or equal to 10 mm, and 77.8% and 85.7% for polyps of 6-9 mm. CONCLUSION: In the context of a screening program for CRC based on FOBT, CTC shows high per-segment and per-lesion PPV for colonic masses and polyps greater than 9 mm. Therefore, CTC has the potential to become a useful technique for evaluation of the non visualized part of the colon after incomplete colonoscopy. 展开更多
关键词 Computed tomography colonography Virtual colonoscopy Incomplete colonoscopy Positive faecal occult blood test Colorectal cancer screening
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Contrastive study of HIV RNA detection and RIBA test in anti-HIV repeated positive donors
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《中国输血杂志》 CAS CSCD 2001年第S1期405-,共1页
关键词 RIBA HIV Contrastive study of HIV RNA detection and RIBA test in anti-HIV repeated positive donors RNA
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Simple Statistical Tests Used in Positive Accounting Research: a Thing to be Noted
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作者 Fengqian Gong 《Chinese Business Review》 2005年第1期13-15,共3页
This paper is concerned with the right use of simple hypothesis tests in the area of positive accounting research. Both the usefulness and the limitations of the technique are dealt with in detail.
关键词 positive accounting hypothesis tests Bayesian interence
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Factors to Give Full Play to the Positive Backwash Effect in the Language Testing
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作者 Guanyu Chen 《Sino-US English Teaching》 2004年第6期50-53,共4页
"Backwash" has usually been described in terms of the effect of testing on language teaching and learning. "Backwash can be harmful or beneficial", as Arthur Hughes states. (Hughes: 1989) This paper set out to ... "Backwash" has usually been described in terms of the effect of testing on language teaching and learning. "Backwash can be harmful or beneficial", as Arthur Hughes states. (Hughes: 1989) This paper set out to see how far this term can be applied to the ways in which both the students and teachers can benefit from language testing. 展开更多
关键词 positive backwash beneficial testing motivation validity and reliability
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三坐标定位器系统动态特性分析和实验 被引量:8
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作者 蒋君侠 陈琪 +1 位作者 方强 柯映林 《计算机集成制造系统》 EI CSCD 北大核心 2009年第5期1004-1009,1040,共7页
为解决飞机传统装配精度低、调整复杂和质量不稳定问题,介绍了三坐标定位器结构与工作原理,建立了伺服传动系统的数学模型,得到系统的传递函数。采用Matlab/Simulink对系统进行仿真模拟,并对三坐标定位器的动态特性进行分析。实验测试... 为解决飞机传统装配精度低、调整复杂和质量不稳定问题,介绍了三坐标定位器结构与工作原理,建立了伺服传动系统的数学模型,得到系统的传递函数。采用Matlab/Simulink对系统进行仿真模拟,并对三坐标定位器的动态特性进行分析。实验测试结果表明,三坐标定位器能够快速、准确地跟踪位置指令,并具有很好的抗干扰能力。对三坐标定位器进行动态特性分析和实验测试,有利于分析与优化系统调姿工作特性,对改进定位器的结构设计具有一定的指导意义。 展开更多
关键词 三坐标定位器 SIMULINK 仿真 动态特性 实验测试
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仿人智能控制在智能电-气阀门定位器中的应用 被引量:7
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作者 吴朋 时光 聂绍忠 《仪器仪表学报》 EI CAS CSCD 北大核心 2009年第9期1930-1934,共5页
智能电-气阀门定位器是阀门执行机构的核心控制部件,智能阀门定位器的控制算法与控制参数的选择直接决定着定位器的性能。针对阀门对象的时变性和非线性的特性,把仿人智能控制应用于智能阀门定位器,完成了仿人智能控制器的运行控制级与... 智能电-气阀门定位器是阀门执行机构的核心控制部件,智能阀门定位器的控制算法与控制参数的选择直接决定着定位器的性能。针对阀门对象的时变性和非线性的特性,把仿人智能控制应用于智能阀门定位器,完成了仿人智能控制器的运行控制级与参数矫正级的设计。智能阀门定位器的自检过程完成对阀门特征的辨识和仿人智能控制的参数整定,并对气体泄漏采取补偿措施,有效减小了气体泄漏所造成的不利影响。仿真与应用结果表明了该算法的有效性。 展开更多
关键词 智能电-气阀门定位器 时变性 非线性 自检 仿人智能控制
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New System to Measure the Yaw and PitchAngles of Rocket in Launch Phase
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作者 王志军 王瑞臣 +1 位作者 王辉 蔡汉文 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期73-77,共5页
Aim To describe a news system for measuring the and pitch angles of rocket during the launch phase Methods Optical system was to reflect the spot that represents the angular movement of rocket to the position sensitiv... Aim To describe a news system for measuring the and pitch angles of rocket during the launch phase Methods Optical system was to reflect the spot that represents the angular movement of rocket to the position sensitive detector that can convert analogue signal into digital one.Results Compared with conventional optical lever test system which had been applied to measure rocket attitude angle,the new system used the position sensitive detector to replace the screen and high-speed photographic instrumentation as grapher,which can avert photointerpretive data reduction and apply to field experiment more easily and pre- cisely .Conclusion Experimental results show that the test system can be used in measuring the yaw and pitch angles of rocket effectively. 展开更多
关键词 ROCKETS attitude angle position sensitive detector test system
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浮头式换热器试压胎具的改进 被引量:3
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作者 祁彦伟 《石油化工设备》 CAS 2007年第1期57-59,共3页
介绍了一种理想的浮头式换热器试压胎具——通用O型环密封试压胎具,并在原理上和使用效果上与填料密封试压胎具和C型环密封试压胎具进行了比较。
关键词 浮头式换热器 试压胎具 密封 O型环 C型环 填料
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工业变位机的精密减速机国产化可行性探讨 被引量:1
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作者 刘佳 白思思 张晓磊 《河北能源职业技术学院学报》 2021年第2期72-74,77,共4页
针对用于工业变位机上的国产320C减速机,根据减速机的最大承载3000kg来进行试验,采用机器人控制外部轴伺服电机的形式驱动转台,在转台上将试验重量从小到大,从均衡负载到偏载,通过试验的往复循环验证减速机的精度、电机减速机的温升、... 针对用于工业变位机上的国产320C减速机,根据减速机的最大承载3000kg来进行试验,采用机器人控制外部轴伺服电机的形式驱动转台,在转台上将试验重量从小到大,从均衡负载到偏载,通过试验的往复循环验证减速机的精度、电机减速机的温升、噪音等内容,由记录数据判定减速机满足试验条件的过程,可替代进口品牌设备。 展开更多
关键词 变位机 减速机 试验
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深水钻井隔水管环焊缝组焊试验装置研制 被引量:1
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作者 肖虎 付堃 +2 位作者 李晓康 张林森 张小龙 《石油矿场机械》 2020年第4期55-58,共4页
基于深水钻井隔水管的使用工况和结构特点,为了对隔水管材料进行焊接工艺研究及优化,研制了隔水管环焊缝组焊试验装置。该试验装置中的变位机解决了大型工件装夹、组对难题,多样化的焊接方法(MIG焊、热丝TIG焊、埋弧焊)利于焊接工艺研究... 基于深水钻井隔水管的使用工况和结构特点,为了对隔水管材料进行焊接工艺研究及优化,研制了隔水管环焊缝组焊试验装置。该试验装置中的变位机解决了大型工件装夹、组对难题,多样化的焊接方法(MIG焊、热丝TIG焊、埋弧焊)利于焊接工艺研究,并扩展了装置的应用范围。试验结果表明,研制的组焊试验装置能够满足隔水管环焊缝的试验研究需要,同时也适用于其他类似产品的组焊生产。 展开更多
关键词 隔水管 试验装置 变位机 焊接方法
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关于部分行程测试的影响因素研究 被引量:2
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作者 蒋浩 范耀峰 钟盛辉 《自动化仪表》 CAS 2020年第11期11-13,16,共4页
为了解决阀门因卡住而无法运行的问题,智能阀门定位器加入部分行程测试(PST)功能,解决了工业生产过程中管道阀门的控制和定位问题,从而满足安全生产的需要。根据阀门运行控制原理,分别对气源压力、脉冲宽度调制(PWM)脉冲个数、执行机构... 为了解决阀门因卡住而无法运行的问题,智能阀门定位器加入部分行程测试(PST)功能,解决了工业生产过程中管道阀门的控制和定位问题,从而满足安全生产的需要。根据阀门运行控制原理,分别对气源压力、脉冲宽度调制(PWM)脉冲个数、执行机构大小、进/排气方向、端点处理、填料摩擦力等因素进行试验数据分析,得出完成PST功能主要考虑这六个方面的影响因素。结合阀门的实际应用控制要求,定位器首次安装之后,要对运行参数进行一次检测自动学习,包括阀门全开码值、全关码值、行程、泄漏量检测、运行速度、始动量、滑动量等参数,从而保证PST的正确控制。在现场控制过程中,PST功能预判由于阀门故障卡死导致阀门不能到达安全位置引起安全事故,从而通过报警输出解决现场故障问题,体现了PST对工业阀门控制的重要性。 展开更多
关键词 部分行程测试 智能阀门定位器 HAX执行机构 I/P转换器 脉冲宽度调制 微处理器 功能安全
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换热管试压胎具的设计
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作者 李拥军 《大氮肥》 CAS 2000年第2期82-83,共2页
在换热设备制造过程中 ,一般要求对换热管进行逐根压力试验或抽验。本文讨论利用换热管端面进行密封的试压胎具的设计。
关键词 换热管 试压 胎具设计 化工设备
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国产300MW机组摆动燃烧器控制系统的改进
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作者 齐俊虎 武俊平 沈国清 《锅炉制造》 2004年第4期29-31,共3页
张家口发电厂5号锅炉改造摆动燃烧器,通过实验建模的方法得出了摆动燃烧器调节再热汽温的对象特性,同时还介绍了该系统的控制策略和现场控制系统,并运用MATLAB软件对控制参数进行了优化。
关键词 摆动燃烧器 试验模型 智能定位器
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209HS型转向架橡胶堆定位器的性能试验与研究
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作者 姜卫星 沈培德 《铁道车辆》 1996年第9期11-16,共6页
在介绍橡胶件静、动态试验要求的基础上,对209HS型准高速转向架的ZSD3型橡胶堆定位器的高、低温试验和静、动态试验工况及试验结果进行了分析。通过试验比较,选择了适合高、低温要求的橡胶堆定位器的材质,保证了定位器的性能。
关键词 转向架 试验 铁路 车辆 ZSD3型 橡胶堆定位器
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Multiple Choice Items in Testing 被引量:1
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作者 陈熙 《长春理工大学学报(高教版)》 2005年第3期51-53,共3页
Language testing is very important and necessary,and moreover as we all know,nowadays,in English language testing, the muhiple-choice item is most widely used and many users regard the multiple-choice item as the most... Language testing is very important and necessary,and moreover as we all know,nowadays,in English language testing, the muhiple-choice item is most widely used and many users regard the multiple-choice item as the most flexible and probably the most effective of the objective item types.The multiple-choice item has its characteristics,advantages and disadvantages.We should bring out its strengths to make up for its weaknesses and use it appropriately.Although it has its limitations,it is suitable for large-scale tests and tests dealing with wide-range knowledge.We should correctly ap- ply testing principles and methods in order to make testing more effective and reliable. 展开更多
关键词 Language testing the multiple choice items characteristics position advantages disadvantages develop principles
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Model-Based Embedded Compiled Software Fault Positioning
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作者 LIU Jinshuo CHEN Jian +2 位作者 ZHANG Weixin XU Xiangyang YAN Jingjing 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第3期263-268,共6页
Software fault positioning is one of the most effective activities in program debugging. In this paper, we propose a model-based fault positioning method to detect the faults of embedded program without source code. T... Software fault positioning is one of the most effective activities in program debugging. In this paper, we propose a model-based fault positioning method to detect the faults of embedded program without source code. The system takes the machine code of embedded software as input and translates the code into high-level language C with the software reverse engineering program. Then, the static analysis on the high-level program is taken to obtain a control flow graph(CFG), which is denoted as a node-tree and each node is a basic block. According to the faults found by the field testing, we construct a fault model by extracting the features of the faulty code obtained by ranking the Ochiai coefficient of basic blocks. The model can be effectively used to locate the faults of the embedded program. Our method is evaluated on ST chips of the smart meter with the corresponding source code. The experiment shows that the proposed method has an effectiveness about 87% on the fault detection. 展开更多
关键词 code reverse engineering model-based test fault positioning
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非限位铝合金定位器的疲劳强度仿真研究
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作者 郑菲 戢敏 陈立明 《计算机仿真》 2024年第11期194-198,共5页
接触网定位器的疲劳强度是影响其服役安全的重要技术指标。在对国外某型非限位铝合金定位器疲劳特性分析的基础上,对定位器进行了疲劳试验,分别得到三种工况下定位器的应力循环次数。通过有限元法对多种工况下定位器危险截面的疲劳强度... 接触网定位器的疲劳强度是影响其服役安全的重要技术指标。在对国外某型非限位铝合金定位器疲劳特性分析的基础上,对定位器进行了疲劳试验,分别得到三种工况下定位器的应力循环次数。通过有限元法对多种工况下定位器危险截面的疲劳强度进行了校核,并估算了其疲劳寿命。仿真结果与试验结果一致,表明采用有限元方法的有效性和可行性。以上研究为国外某型高速定位器在我国的安全使用提供了技术支撑,对定位器的工作性能研究及其优化设计效果评估具有一定的指导意义。 展开更多
关键词 定位器 疲劳试验 疲劳强度 疲劳寿命 有限元仿真
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Quantities and function of NK cells in patients with positive BMMNC-Coombs test and cytopenia
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作者 袁鑫 《China Medical Abstracts(Internal Medicine)》 2016年第3期182-183,共2页
Objective To test NK cell quantities and function in patients with positive BMMNC-Coombs test(CBCPC)and cytopenia and to explore how NK cell participate in the progress of this disease.Methods The percentage of CD3-CD... Objective To test NK cell quantities and function in patients with positive BMMNC-Coombs test(CBCPC)and cytopenia and to explore how NK cell participate in the progress of this disease.Methods The percentage of CD3-CD56+NK cell in peripheral blood lymphocytes,the expression of activating receptor(NKG2D,NKp46,NKp44),inhibitory receptor(CD158a,CD158b),per- 展开更多
关键词 BMMNC test cell Quantities and function of NK cells in patients with positive BMMNC-Coombs test and cytopenia NK
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