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猿猴免疫缺陷病毒_(大猩猩)具有跨物种以及在人群中传播的能力

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新发传染病电子杂志 2023年第3期8卷 1-6页

作者：邹薇邬小萍陈新萍刘梨邹世杰 john Foster JVictor Garcia 南昌大学第一附属医院感染科江西南昌330006 南昌大学第一附属医院妇产科江西南昌330006 北卡罗来纳大学教堂山分校艾滋病研究中心美国北卡罗来纳州 27514

目的西非大猩猩(Gorilla gorilla gorilla)是猿猴免疫缺陷病毒大猩猩(SIVgor)的天然宿主。本研究旨在确定SIVgor能否传播给人类并在人体内复制。方法首先将25只6~8周的NOD/SCIDIL-2Rγc^(-/-)小鼠通过尾静脉注射移植人造血干细胞入免疫... 详细信息

目的西非大猩猩(Gorilla gorilla gorilla)是猿猴免疫缺陷病毒大猩猩(SIVgor)的天然宿主。本研究旨在确定SIVgor能否传播给人类并在人体内复制。方法首先将25只6~8周的NOD/SCIDIL-2Rγc^(-/-)小鼠通过尾静脉注射移植人造血干细胞入免疫缺陷小鼠中,构建有完整人造血系统的人源化小鼠。然后通过静脉(5只)、直肠(7只)和阴道(5只)三种途径将人源化小鼠暴露于9×10~4TCIU的SIVgor,每2周检测人源化小鼠体内HIV的病毒载量和CD4^(+)T淋巴细胞水平,评估三种暴露途径SIVgor的传播能力、体内复制能力以及对CD4^(+)T淋巴细胞的杀伤力。结果静脉暴露后,SIVgor在人源化小鼠中高效复制,病毒载量达到与HIV感染的人类相当。直肠和阴道接种病毒也导致人源化小鼠感染SIVgor。尽管SIVgor在人源化小鼠体内高水平复制,但外周血中人CD4^(+)T淋巴细胞水平在三种暴露途径导致的感染中仅略有下降。而三种暴露途径导致的感染对小鼠其他组织中人CD4^(+)T淋巴细胞的影响则略有不同:阴道暴露使阴道中的CD4^(+)T淋巴细胞明显下降,而对其他组织中的人CD4^(+)T淋巴细胞无影响;静脉和直肠暴露对各组织中人CD4^(+)T淋巴细胞水平的影响不大。结论SIVgor能通过静脉、直肠和阴道途径感染人源化小鼠并在其内高效复制。黏膜相关淋巴组织中SIVgor对CD4^(+)T淋巴细胞的选择性细胞毒性与人类HIV-1感染相似。由于人类仍可因狩猎暴露于SIVs,新的人畜共患病可能再次发生。因此,建立能评估当前和未来人畜共患病的模型系统至关重要。

关键词：猿猴免疫缺陷病毒_(大猩猩) 人类免疫缺陷病毒 CD4^(+)T淋巴细胞人源化小鼠

Studies on electroless Ni-p-Cr_2O_3 and Ni-p-SiO_2 composite coatings

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电镀与涂饰 2007年第1期26卷 1-6页

作者： KARTHIKEYAN S SRINIVASAN K N VASUDEVAN T john S National Engineering College K.R.NagarKovilpatti-628503TamilnaduIndia Central Electrochemical Research Institute Karaikudi-630006India Alagappa University Karaikudi-630003India

本文对化学镀镍及化学镀镍磷基质中SiO2与Cr2O3的共沉积进行了研究。微粒在不断生长的膜层中共沉积引起了新的化学复合镀层的出现,这些复合镀层许多都具有优异的耐磨及耐蚀性能。通过选取镀层合金/复合微粒/金属基体的组分可改进镀层,... 详细信息

本文对化学镀镍及化学镀镍磷基质中SiO2与Cr2O3的共沉积进行了研究。微粒在不断生长的膜层中共沉积引起了新的化学复合镀层的出现,这些复合镀层许多都具有优异的耐磨及耐蚀性能。通过选取镀层合金/复合微粒/金属基体的组分可改进镀层,获得所需的性能,以满足特别的需求。在对这些复合镀层的应用需求正在迫近与增长的同时,其市场正在迅速扩张。本文开发出了一种合适的复合化学镀镍液,并通过维氏硬度法对化学复合镀镍层进行了表征。采用动电位极化及交流阻抗法测定了镀层的Taber耐磨性能及耐蚀性能。采用SEM及XRD对复合镀层的表面形貌进行了分析。

关键词：化学镀镍化学复合镀层SiO2 Cr2O3 共沉积维氏硬度法动电位极化交流阻抗

prediction of Gestational Diabetes Mellitus in Early pregnancy: Is Abdominal Skin Fold Thickness 20 mm or More an Independent Risk predictor?

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Journal of Biosciences and Medicines 2017年第11期5卷 13-26页

作者： Vaduneme Kingsley Oriji john Dimkpa Ojule Bassey Offiong Fumudoh Department of Obstetrics and Gynaecology University of Port Harcourt Teaching Hospital Port Harcourt Nigeria Department of Obstetrics and Gynaecology Federal Medical Centre Yenagoa Nigeria

Background: Gestational Diabetes Mellitus (GDM) is associated with several maternal and perinatal complications. Early detection and treatment can improve pregnancy outcomes. Objectives: To determine the prevalence, risk factors and predictors of GDM in early pregnancy at the University of port Harcourt Teaching Hospital, (UpTH), port Harcourt Nigeria. Methods: A cohort of 235 mothers who registered for antenatal care between 15 - 18 weeks of gestation at UpTH was prospectively studied. Their socio-demographic data, examination findings, anthropometric measurements, fasting blood sugar at booking and OGTT results at 28 weeks gestation were collated and entered into pC with SpSS for windows version 21.0 which was also used for the analysis. Variables were expressed as absolute numbers, percentages or means with standard deviations and significant differences determined using chi square test or the student “t” test as appropriate. The level of significance was set at p participants, 35 (14.9%) developed GDM. Women who had GDM were significantly older (p = 0.001), had higher weight (t = 2.95, p = 0.01), BMI (t = 2.29, p = 0.02), abdominal skin fold thickness (t = 4.15, p = 0.001), blood pressure (t = 3.38, p = 0.001) compared to women who did not. previous history of GDM was significantly different between two groups as χ2 = 93.56 and p = 0.001. Abdominal skin fold thickness and prior GDM history were found to be independent predictors of GDM on application of multiple logistic regression analysis. Conclusion: The prevalence of GDM in port Harcourt is 14.9% and major risk factors are obesity, previous GDM history, advanced age and hypertension. Abdominal skin fold thickness ≥ 20 mm is an independent predictor. The risk of developing GDM can be predicted in early second trimester using algorithm incorporating risk factor screening and anterior abdominal wall skin fold thickness estimation.

关键词： Gestational Diabetes Mellitus Risk Factors Detection Early pregnancy port Harcourt

Integrated Landsat Imagery and Geophysical Exploration for Groundwater potential Evaluation of Okene and Its Environs, Southwestern Nigeria

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International Journal of Geosciences 2015年第3期6卷 209-229页

作者： john Olurotimi Amigun Richard Ajibola Faruwa Akinola Adesuji Komolafe Department of Applied Geophysics Federal University of Technology Akure Akure Nigeria Department of Remote Sensing and Geoscience Information System Federal University of Technology Akure Akure Nigeria

In this study, an integrated remote sensing and geophysical (aeromagnetic and geo-electric) methods was employed to assess the potential of groundwater in a basement complex terrain of Okene and its environs, Southwestern, Nigeria. Landsat imagery acquired over the study area was processed in the Geographic Information Systems (GIS) environment to delineate the surface lineaments, drainage networks and their orientations. Aeromagnetic data over the area were analyzed and its derivative maps were interpreted to further map the structures and the geology in the subsurface;depths to magnetic sources were determined using spectral analysis. Vertical Electrical Sounding (VES) of geo-electric method was interpreted to map the subsurface geology layers. The results of the integrated data were correlated with borehole yield data of the area for effective interpretation. Delineated lineaments from the azimuth, frequency plot showed dominant trends in the NE-SW and NNE-SSW directions. Radial average power spectrum revealed the depth to magnetic sources between 100 and 2500 m and the interpreted VES data characterized the area into three to four subsurface layers. In correlating the results with borehole yield data, the zones with high lineament density and low/negative magnetic anomaly were categorized as high groundwater potential zones while areas with low lineament density and high/positive magnetic anomaly as low groundwater potential zones. This study will guide efficiently subsequent groundwater drilling program in the study area.

关键词： Groundwater Basement Complex Aeromagnetic Geo-Electrics Remote Sensing GIS

Brachial plexus Neuropraxia after CT-Guided Radiofrequency Ablation in a patient with a Narrow Costoclavicular Space: A Case Report

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Open Journal of Anesthesiology 2017年第11期7卷 357-363页

作者： john paul Lew Yan Ru Tan Yee Yian Ong Division of Anaesthesiology Singapore General Hospital Singapore

A case of brachial plexus neuropraxia occurring during CT-guided radiofrequency ablation is reported in a patient with a narrow costoclavicular space. We discuss clinical methods of identifying patients with a narrow costoclavicular space who are at risk of position-related injury of the brachial plexus during anaesthesia. Identifying high risk patients and proper positioning during anaesthesia are hallmarks of preventing such injuries.

关键词： Brachial plexus Injuries Anaesthesia Interventional Radiology Narrow Costoclavicular Space Complication

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田间农药雾滴精准采样技术与发展趋势

农业工程学报 2021年第11期37卷 1-12页

作者：王国宾李烜 john Andaloro 陈盛德韩小强王娟单常峰兰玉彬山东理工大学农业工程与食品科学学院淄博255049 山东省农业航空智能装备工程技术研究中心淄博255049 FMC Corporation Stine Research Center1090 Elkton RoadNewarkDE 19711USA 华南农业大学电子工程学院(人工智能学院) 广州510642 石河子大学农学院石河子832002 海南大学机电工程学院海口570228

采用植保机械喷施化学农药仍是病虫害防治最为有效的手段。喷施过程中,农药雾滴精准的采集并测定沉积、流失飘移量,对于优化植保机械的作业参数、提高农药利用率具有重要意义。该研究综述分析了室内与田间采样过程中不同类型采样器的优... 详细信息

采用植保机械喷施化学农药仍是病虫害防治最为有效的手段。喷施过程中,农药雾滴精准的采集并测定沉积、流失飘移量,对于优化植保机械的作业参数、提高农药利用率具有重要意义。该研究综述分析了室内与田间采样过程中不同类型采样器的优缺点,并分析采样效率、采样器的布置及采样条件等因素对雾滴沉积、流失飘移采样结果的影响。针对当前的采样方法,该研究提出了未来在农药雾滴采样方面的5点要求与展望,包括提高采样的准确性、提高采样方法和采样设备的标准化、增加对农药有效成分雾滴运动规律的研究、研发新型的采样传感器以提高采样效率、建立植保无人飞机喷施雾滴沉积、飘移模型。综上,通过更为标准化和精准的采样,获取可比较、准确度高的农药雾滴沉积与流失飘移数据,可为中国农药使用量“零增长”提供科学技术指导。

关键词：植保机械农药喷雾雾滴沉积雾滴流失雾滴飘移采样方法

On the Norm of Elementary Operator

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Advances in pure Mathematics 2014年第7期4卷 309-316页

作者： Denis Njue Kingangi john Ogoji Agure Fredrick Oluoch Nyamwala Department of Mathematics and Computer Science University of Eldoret Eldoret Kenya Department of physics Mathematics Statistics and Computer Science Moi University Eldoret Kenya Department of pure and Applied Mathematics Maseno University Maseno Kenya

The norm of an elementary operator has been studied by many mathematicians. Varied results have been established especially on the lower bound of this norm. Here, we attempt the same problem for finite dimensional ope... 详细信息

关键词： Bounded Linear Operator Elementary Operator

语言教学法效率的最大化——从经济学角度看提高教学法的效率

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世界汉语教学 2018年第4期32卷 517-533页

作者：俞志强美国纽约城市大学现代语言与比较文学系

外语教学法的效率问题研究一直是一个盲区,从经济学角度进行的相关研究几乎空白。经济学提供了有力的观察工具。旧有的教学法只强调效力的最大化,新的教学法还应注重效率的最大化,应研究如何用最小的教学成本取得最大的教学效益。

关键词：效力效率效益边际效应教学成本

Comparison of cognitive and UHDRS measures in monitoring disease progression in Huntington’s disease: a 12-month longitudinal study

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Translational Neurodegeneration 2014年第1期3卷 109-118页

作者： Eng A Toh Michael R MacAskill john C Dalrymple-Alford Daniel J Myall Leslie Livingston Sandy AD Macleod Tim J Anderson Department of Medicine Christchurch School of Medicine&Health SciencesUniversity of OtagoChristchurchNew Zealand New Zealand Brain Research Institute ChristchurchNew Zealand Department of psychology University of CanterburyChristchurchNew Zealand Brain Injury Rehabilitation Service Canterbury District Health BoardChristchurchNew Zealand Department of Neurology Canterbury District Health BoardChristchurchNew Zealand

progressive cognitive decline is a feature of Huntington’s disease(HD),an inherited neurodegenerative movement *** neuropsychological testing is the‘gold standard’to establish cognitive status but is often impractical in time-constrained *** study evaluated the utility of brief cognitive tests(MMSE and MoCA),UHDRS measures and a comprehensive neuropsychological tests battery in monitoring short-term disease progression in ***-two manifest HD patients and 22 matched controls were assessed at baseline and 12-month.A linear mixed-effect model showed that although the HD group had minimal change in overall global cognition after 12 months,they did show a significant decline relative to the control *** controls exhibited a practice effect in most of the cognitive domain scores over *** decline at 12-month in HD was found in the executive function domain but the effect of this on global cognitive score was masked by the improvement in their language domain *** varying practice effects by cognitive domain with repeated testing indicates the importance of comparing HD patients to control group in research trials and that cognitive progression over 12 months in HD should not be judged by changes in global cognitive *** three brief cognitive tests effectively described cognition of HD patients on cross-sectional *** UHDRS cognitive component,which focuses on testing executive function and had low variance over time,is a more reliable brief substitute for comprehensive neuropsychological testing than MMSE and MoCA in monitoring cognitive changes in HD patients after 12 months.

关键词： Huntington’s disease Disease progression Cognition UHDRS Longitudinal