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Epidemiological Surveillance: Genetic Diversity of Rotavirus Group A in the Pearl River Delta, Guangdong, China in 2019
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作者 JIANG Jie Ying LIANG Dan +9 位作者 WANG Li XIAO Yun LIANG Yu Feng KE Bi Xia SU Juan XIAO Hong WANG Tao ZOU Min LI Hong Jian KE Chang Wen 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第3期278-293,共16页
Objective This study aimed to understand the epidemic status and phylogenetic relationships of rotavirus group A(RVA)in the Pearl River Delta region of Guangdong Province,China.Methods This study included individuals ... Objective This study aimed to understand the epidemic status and phylogenetic relationships of rotavirus group A(RVA)in the Pearl River Delta region of Guangdong Province,China.Methods This study included individuals aged 28 days–85 years.A total of 706 stool samples from patients with acute gastroenteritis collected between January 2019 and January 2020 were analyzed for 17 causative pathogens,including RVA,using a Gastrointestinal Pathogen Panel,followed by genotyping,virus isolation,and complete sequencing to assess the genetic diversity of RVA.Results The overall RVA infection rate was 14.59%(103/706),with an irregular epidemiological pattern.The proportion of co-infection with RVA and other pathogens was 39.81%(41/103).Acute gastroenteritis is highly prevalent in young children aged 0–1 year,and RVA is the key pathogen circulating in patients 6–10 months of age with diarrhea.G9P[8](58.25%,60/103)was found to be the predominant genotype in the RVA strains,and the 41 RVA-positive strains that were successfully sequenced belonged to three different RVA genotypes in the phylogenetic analysis.Recombination analysis showed that gene reassortment events,selection pressure,codon usage bias,gene polymorphism,and post-translational modifications(PTMs)occurred in the G9P[8]and G3P[8]strains.Conclusion This study provides molecular evidence of RVA prevalence in the Pearl River Delta region of China,further enriching the existing information on its genetics and evolutionary characteristics and suggesting the emergence of genetic diversity.Strengthening the surveillance of genotypic changes and gene reassortment in RVA strains is essential for further research and a better understanding of strain variations for further vaccine development. 展开更多
关键词 Infectious diarrheal disease rotavirus Phylogenetic analysis Gene rearrangement Codon usage bias Genetic diversity
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The protective role of prebiotics and probiotics on diarrhea and gut damage in the rotavirus-infected piglets
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作者 Heng Yang Xiangqi Fan +4 位作者 Xiangbing Mao Bing Yu Jun He Hui Yan Jianping Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1424-1448,共25页
Rotavirus is one of the pathogenic causes that induce diarrhea in young animals, especially piglets, worldwide. However, nowadays, there is no specific drug available to treat the disease, and the related vaccines hav... Rotavirus is one of the pathogenic causes that induce diarrhea in young animals, especially piglets, worldwide. However, nowadays, there is no specific drug available to treat the disease, and the related vaccines have no obvious efficiency in some countries. Via analyzing the pathogenesis of rotavirus, it inducing diarrhea is mainly due to disturb enteric nervous system, destroy gut mucosal integrity, induce intracellular electrolyte imbalance, and impair gut microbiota and immunity. Many studies have already proved that prebiotics and probiotics can mitigate the damage and diarrhea induced by rotavirus infection in hosts. Based on these, the current review summarizes and discusses the effects and mechanisms of prebiotics and probiotics on rotavirus-induced diarrhea in piglets. This information will highlight the basis for the swine production utilization of prebiotics and probiotics in the prevention or treatment of rotavirus infection in the future. 展开更多
关键词 DIARRHEA PIGLET PREBIOTICS PROBIOTICS rotavirus
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RV减速器的多目标层次优化设计
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作者 丁国龙 叶梦传 +1 位作者 吴熙 余运清 《机械设计与制造》 北大核心 2024年第3期67-72,共6页
为了使RV减速器的结构更加紧凑、传动效率更高和承载能力更强,提出了一种基于层次分析法(AHP)的RV减速器多目标优化设计方法。以RV减速器的体积、传动效率和摆线轮接触应力为多目标函数,借助层次分析法(AHP)对优化目标进行评估,计算各... 为了使RV减速器的结构更加紧凑、传动效率更高和承载能力更强,提出了一种基于层次分析法(AHP)的RV减速器多目标优化设计方法。以RV减速器的体积、传动效率和摆线轮接触应力为多目标函数,借助层次分析法(AHP)对优化目标进行评估,计算各个目标的权重,将多个目标通过加权法转化为单目标函数,其次建立了包含参数范围、强度校核及结构限制的约束条件。最后利用遗传算法(GA)实现多目标优化设计问题的求解。优化结果表明,优化后的RV减速器体积减小、传动效率更高、承载能力更强,综合性能提高了8.0%。为实际生产应用中减速器的优化设计提供理论和方法指导。 展开更多
关键词 rv减速器 层次分析法(AHP) 多目标优化 优化设计 遗传算法
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偏载作用下RV减速器主轴承启停动态特性研究
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作者 殷新科 杨芳 +1 位作者 李济顺 黎建涛 《机械强度》 CAS CSCD 北大核心 2024年第3期701-707,共7页
为了获得RV减速器启停工况下主轴承的动态响应特性,以某型RV减速器主轴承为研究对象,分析轴承的径向和轴向偏载作用情况;在此基础上建立轴承多刚体动力学仿真模型,结合工况设置载荷、转速和接触参数,并验证模型有效性;仿真分析了RV减速... 为了获得RV减速器启停工况下主轴承的动态响应特性,以某型RV减速器主轴承为研究对象,分析轴承的径向和轴向偏载作用情况;在此基础上建立轴承多刚体动力学仿真模型,结合工况设置载荷、转速和接触参数,并验证模型有效性;仿真分析了RV减速器主轴承启动和减速停止工况对轴承滚子与保持架、内外圈接触力的影响规律。结果表明,RV减速器主轴承滚子与保持架接触力受启停工况的影响,启动加速阶段碰撞最为激烈,平稳时次之,减速时最小;在启动加速和减速停止阶段,滚子与内圈接触力波动范围为平稳运行时的15倍,为研究RV减速器主轴承的动态特性及寿命试验提供了理论基础。 展开更多
关键词 rv减速器 主轴承 动态特性 转速 接触力
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Clinical factors predicting rotavirus diarrhea in children:A crosssectional study from two hospitals 被引量:1
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作者 Michelle Indrawan Jason Chendana +2 位作者 Tan Gabriella Heidina Handoko Melanie Widjaja Gilbert Sterling Octavius 《World Journal of Clinical Pediatrics》 2023年第5期319-330,共12页
BACKGROUND Rotavirus is still a significant contributing morbidity and mortality in pediatric patients.AIM To look at clinical signs and symptoms and laboratory findings that can predict rotavirus gastroenteritis comp... BACKGROUND Rotavirus is still a significant contributing morbidity and mortality in pediatric patients.AIM To look at clinical signs and symptoms and laboratory findings that can predict rotavirus gastroenteritis compared to non-rotavirus gastroenteritis.METHODS This was a cross-sectional study with medical records obtained from December 2015 to December 2019.Inclusion criteria for this study include all hospitalised pediatric patients(0-18 years old)diagnosed with suspected rotavirus diarrhea.The receiver operating curve and Hosmer-Lemeshow test would be used to assess the final prediction findings'calibration(goodness of fit)and discrimination performance.RESULTS This study included 267 participants with 187(70%)rotavirus-diarrhea cases.The patients were primarily male in both rotavirus(65.2%)and non-rotavirus(62.5%)groups.The median age is 1.33 years old(0.08-17.67 years old).Multivariate analysis shows that wet season(OR_(adj)=2.5;95%CI:1.3-4.8,Padj=0.006),length of stay(LOS)≥3 days(OR_(adj)=5.1;95%CI:1.4-4.8,Padj=0.015),presence of abdominal pain(OR_(adj)=3.0;95%CI:1.3-6.8,Padj=0.007),severe dehydration(OR_(adj)=2.9;95%CI:1.1-7.9,Padj=0.034),abnormal white blood cell counts(OR_(adj)=2.8;95%CI:1.3-6.0,Padj=0.006),abnormal random blood glucose(OR_(adj)=2.3;95%CI:1.2-4.4,Padj=0.018)and presence of fecal leukocytes(OR_(adj)=4.1,95%CI:1.7-9.5,Padj=0.001)are predictors of rotavirus diarrhea.The area under the curve for this model is 0.819(95%CI:0.746-0.878,P value<0.001),which shows that this model has good discrimination.CONCLUSION Wet season,LOS≥3 d,presence of abdominal pain,severe dehydration,abnormal white blood cell counts,abnormal random blood glucose,and presence of fecal leukocytes predict rotavirus diarrhea. 展开更多
关键词 rotavirus PEDIATRIC GASTROENTERITIS DIARRHEA Indonesia
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结核分枝杆菌潜伏感染抗原Rv2628c-Rv1737c融合蛋白的原核表达与免疫原性分析
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作者 解建辉 李昆 +3 位作者 孙卫国 贺雄 朱琰 张灵霞 《中国人兽共患病学报》 CAS CSCD 北大核心 2024年第1期7-14,共8页
目的原核系统表达、纯化结核分枝杆菌潜伏感染抗原Rv2628c-Rv1737c融合蛋白,并检测其能否被结核感染者外周血PBMC细胞识别,通过小鼠模型判定其免疫原性。方法按照原核系统密码子特点,全基因合成Rv2628c-Rv1737c表达核酸序列,构建表达质... 目的原核系统表达、纯化结核分枝杆菌潜伏感染抗原Rv2628c-Rv1737c融合蛋白,并检测其能否被结核感染者外周血PBMC细胞识别,通过小鼠模型判定其免疫原性。方法按照原核系统密码子特点,全基因合成Rv2628c-Rv1737c表达核酸序列,构建表达质粒pET24a-Rv2628c-Rv1737c,原核细胞内诱导表达、亲和层析纯化Rv2628c-Rv1737c蛋白;分离不同患者样本PBMC细胞,抗原刺激后,通过q-PCR分析IFN-γmRNA表达差异,判定融合蛋白能否被TB感染者识别;联合融合佐剂DMT免疫BALB/c小鼠,检测体液免疫应答水平。结果原核克隆的重组表达质粒pET24a-Rv2628c-Rv1737c测序正确,融合蛋白以包涵体表达形式存在,经复性、亲和纯化后,分子量为57 kDa,纯度90%以上。以Rv2628c-Rv1737c融合蛋白刺激TB感染者,尤其TB潜伏感染(LTBI)者,外周血PBMC细胞IFN-γmRNA水平高于健康对照者(P<0.05);同时,BCG+Rv2628c-Rv1737c/DMT诱导小鼠能产生高水平的IgG抗体。结论原核重组可获得高纯度Rv2628c-Rv1737c融合蛋白,其作为潜伏感染抗原,可被TB感染者PBMC细胞识别,具有较强的免疫原性,是具有潜力的TB候选亚单位疫苗靶抗原,可用于TB感染尤其是潜伏感染的预防及实验室诊断。 展开更多
关键词 结核分枝杆菌 潜伏感染 rv2628c蛋白 rv1737c蛋白 Γ干扰素
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伺服特征信息与RV减速器负载关联性研究
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作者 李恒 赵兵 +1 位作者 赖泳辉 张申 《航空制造技术》 CSCD 北大核心 2024年第5期95-102,共8页
针对现有RV减速器工况识别中传感器安装位置受限和采集信号易受外界噪声干扰等问题,综合利用伺服特征信息对RV减速器工作状况进行监测,提高工业机器人在制造领域的服役性能。首先,根据RV减速器的结构参数及工作机制,分析输入转速与RV减... 针对现有RV减速器工况识别中传感器安装位置受限和采集信号易受外界噪声干扰等问题,综合利用伺服特征信息对RV减速器工作状况进行监测,提高工业机器人在制造领域的服役性能。首先,根据RV减速器的结构参数及工作机制,分析输入转速与RV减速器关键频率、伺服特征信息与负载之间的关联性;然后,基于K-means聚类算法构建伺服特征信息与RV减速器负载之间的关联性辨识模型;最后,通过搭建RV减速器试验平台采集不同负载工况下伺服系统反馈信息,进行相应处理后运用关联辨识模型,实现了对负载状态的精确识别,识别率高达97.45%。本文可为基于伺服特征信息的RV减速器运行状态监测提供技术支撑。 展开更多
关键词 工业机器人 特征信息 rv减速器 K-MEANS聚类 负载 关联性
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面向传动性能的分体式RV减速器结构优化
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作者 杨晨昊 王金栋 +1 位作者 李澳 唐雷雨 《组合机床与自动化加工技术》 北大核心 2024年第4期72-77,82,共7页
针对当前国产RV减速器加工成本高,传动效率低等问题,提出分体式摆线轮结构对原齿廓进行优化以减少加工难度,提升加工效率。分析RV减速器传动原理,提出了分体式摆线轮的设计方法,确定各零部件的参数尺寸,以负载性能,传动精度,传动效率为... 针对当前国产RV减速器加工成本高,传动效率低等问题,提出分体式摆线轮结构对原齿廓进行优化以减少加工难度,提升加工效率。分析RV减速器传动原理,提出了分体式摆线轮的设计方法,确定各零部件的参数尺寸,以负载性能,传动精度,传动效率为评价指标,构建多目标评价函数,采用NSGA算法实现面向性能的RV减速器结构参数优化。构建RV减速器三维模型,采用Adams动力学分析对其各项指标进行评定,验证设计方法的有效性。同时,采用有限元分析对设计出RV减速器结构的合理性进行验证分析。 展开更多
关键词 rv减速器 遗传算法 结构分析 运动仿真 模态分析
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基于IAS信号自适应窄带解调的RV减速器摆线轮故障特征提取
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作者 张珈源 郭瑜 《振动与冲击》 EI CSCD 北大核心 2024年第9期261-266,共6页
RV(rotary vector)减速器广泛应用于工业机器人,研究其关键零部件的故障检测方法具有重要意义。由于RV减速器结构复杂、摆线轮转速低、故障冲击较弱等问题,造成摆线轮故障特征难以用常规振动分析方法提取。针对上述问题,提出一种基于瞬... RV(rotary vector)减速器广泛应用于工业机器人,研究其关键零部件的故障检测方法具有重要意义。由于RV减速器结构复杂、摆线轮转速低、故障冲击较弱等问题,造成摆线轮故障特征难以用常规振动分析方法提取。针对上述问题,提出一种基于瞬时角速度信号自适应窄带解调的RV减速器摆线轮故障特征提取方法。首先对编码器角度信号进行采集,然后使用向前差分法获得瞬时角速度信号,在此基础上,使用角域同步平均提取摆线轮周期相关同步分量,消除非同步干扰,并通过构建边带信噪比指标选取故障信息丰富的啮合谐波频带进行带通滤波,最后对滤波后的信号进行窄带解调,实现对RV减速器摆线轮的故障特征提取。试验结果表明,该方法可以有效地提取RV减速器摆线轮故障特征,且自适应实现优化带宽选择。 展开更多
关键词 rv减速器 摆线轮 瞬时角速度 边带信噪比指标 窄带解调技术
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Neonatal erythema multiforme associated with a rotavirus infection:A case report
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作者 Jung Jae Kim Joon Kee Lee 《World Journal of Clinical Cases》 SCIE 2023年第24期5749-5754,共6页
BACKGROUND Erythema multiforme(EM)is an extremely rare condition in neonates,and studies suggest its association with certain infections and neonatal vaccinations;however,few specific etiological agents have been iden... BACKGROUND Erythema multiforme(EM)is an extremely rare condition in neonates,and studies suggest its association with certain infections and neonatal vaccinations;however,few specific etiological agents have been identified.Rotavirus,a common pathogenic gastrointestinal virus in the neonatal period that is preventable via vaccination,has not been identified as a possible etiology.We report the case of a neonate who was referred for skin lesions presenting as EM,where a meticulous workup identified rotavirus as the sole causative agent.CASE SUMMARY A 14-day-old male infant was admitted to our hospital with a 1-day history of skin lesions.No medical history or medication intake was recorded.Except for the complaint of skin lesions,the caregivers denied any abnormal symptoms.Multiple tests,including routine laboratory evaluations,were performed to identify the cause of skin lesions.Serological tests for Immunoglobulin M for Toxoplasma,Rubella,Cytomegalovirus,Herpes Simplex Virus,and Epstein-Barr virus viral-capsid antigen were all negative.Multiple polymerase chain reaction(PCR)tests for respiratory viruses and bacterial pathogens were negative(including the severe acute respiratory syndrome coronavirus 2).Multiple PCR tests for gastrointestinal viruses and bacterial pathogens demonstrated evidence of rotavirus infection.No growth was reported in the blood and urine cultures.The patient received intravenous fluids for hydration;meanwhile,no other medications were prescribed.The lesions improved rapidly without specific treatment,and full recovery was achieved within a week.CONCLUSION The possibility of rotavirus,a major cause of pediatric gastrointestinal infections,being a trigger for neonatal EM should be considered. 展开更多
关键词 Erythema multiforme Gastrointestinal diseases NEONATE rotavirus Skin abnormalities Case report
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Evaluation of Hyperimmune Hen Egg Yolk Derived Anti-Human Rotavirus Antibodies (Anti-HRVIgY) against Rotavirus Infection 被引量:1
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作者 Manika Buragohain Ganesh S. Dhale +1 位作者 Govind R. Ghalsasi Shobha D. Chitambar 《World Journal of Vaccines》 2012年第2期73-84,共12页
Oral delivery of specific IgY has been reported to be beneficial against rotavirus infection. However, the production of IgYs against globally prevalent human rotavirus (HRV) serotypes and their evaluation detailing t... Oral delivery of specific IgY has been reported to be beneficial against rotavirus infection. However, the production of IgYs against globally prevalent human rotavirus (HRV) serotypes and their evaluation detailing the influence on the virological/histopathological consequences have not been reported to date. In the present study, anti-HRVIgY was generated in the eggs of specific pathogen free hens immunized with HRV serotypes G1 - G4 and G9 independently. Purified anti-HRVIgY preparations were tested to determine the ELISA and neutralizing antibody titers respectively in an indirect ELISA and cell culture based neutralization assay. Efficacy of pre and post infection treatment of anti-HRV-3IgY was assessed in an infant BALB/c mouse model of human rotavirus infection by monitoring percent diarrhea, severity and duration of diarrhea, intestinal viral load and histopathology. High (1:64000 - 1:512000) titered anti-HRVIgYs were obtained from the egg yolk of immunized hens with peak titer value (1:256000/1:512000) at 40 - 60 day of immunization. In-vitro, each of the anti-HRVIgY preparations showed the presence of multiserotypic neutralizing activity with high (1:1600 - ≥1:6400) homologous and low (≤1:50 - 1:800) heterologous titers. However, anti-HRV-3IgY neutralized all of the serotypes tested in the study indicating broader in-vitro neutralizing activity. In mice, post exposure treatment with anti-HRV-3IgY significantly reduced the extent of diarrhea and intestinal virus load and inhibited histopathological changes whereas pre exposure anti-HRV-3IgY treatment imparted immediate protection from development of rotavirus gastroenteritis. Thus, the anti-HRVIgY administered orally decreased morbidity and disease incidences in mice suggesting its potential implication in prophylactic and therapeutic usage in human to achieve reduction in rotavirus disease burden. 展开更多
关键词 IGY rotavirus Mouse Model Oral Immunotherapy
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DosR抗原Rv1737c用于活动性肺结核和潜伏性结核病感染的区分诊断评价
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作者 郑鸽之 许娟 +2 位作者 石磊 李洁洁 贺婷 《兰州大学学报(医学版)》 2024年第5期34-40,共7页
目的评价结核分枝杆菌(MTB)潜伏相关抗原Rv1737c用于活动性肺结核(ATB)和潜伏性结核病感染(LTBI)的诊断价值。方法纳入西安交通大学第一附属医院感染科2022年1月—2023年8月294例ATB病例和299例LTBI病例。用荧光斑点(FluoroSpot)法检测... 目的评价结核分枝杆菌(MTB)潜伏相关抗原Rv1737c用于活动性肺结核(ATB)和潜伏性结核病感染(LTBI)的诊断价值。方法纳入西安交通大学第一附属医院感染科2022年1月—2023年8月294例ATB病例和299例LTBI病例。用荧光斑点(FluoroSpot)法检测特异性T细胞经MTB毒力因子ESAT-6和CFP-10、MTB潜伏相关抗原Rv1737c刺激后分泌的IFN-γ和IL-2。受试者操作特征(ROC)曲线用于定义在区分ATB和LTBI时潜伏期相关抗原的最佳截断值。结果在MTB特异性ESAT-6和CFP-10肽刺激后,ATB组仅分泌IFN-γ的T细胞(IFN-γ+T细胞)百分比显著高于LTBI组(P<0.001);相反,仅分泌IL-2的T细胞(IL-2+T细胞)百分比显著低于LTBI组(P<0.001)。MTB潜伏相关抗原Rv1737c刺激后,LTBI组IL-2+T细胞百分比显著高于ATB组(P<0.001)。由Rv1737c刺激的IL-2+T细胞百分比得出的ROC曲线下面积(AUC)为0.812(95%CI:[0.775,0.850]),区分ATB和LTBI的敏感性和特异性分别为81.9%和84.4%。仅考虑ESAT-6或CFP-10刺激的IFN-γ+T细胞百分比,ESAT-6及CFP-10 FluoroSpot对ATB和LTBI鉴别诊断的敏感性和特异性分别为77.6%和75.3%,AUC值为0.739(95%CI:[0.695,0.782])。在ESAT-6和CFP-10 FluoroSpot的基础上,与Rv1737c联合使用可将特异性提高到92.3%(95%CI:[0.872,0.994]),AUC增加至0.881(95%CI:[0.853,0.910])。结论Rv1737c与ESAT-6和CFP-10结合,可作为基于T细胞的结核病诊断测试的候选抗原,用于区分ATB和LTBI。 展开更多
关键词 结核分枝杆菌 活动性肺结核 DosR抗原 rv1737c 诊断 潜伏性结核病感染
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Rapid genotyping of human rotavirus using SYBR green real-time reverse transcription-polymerase chain reaction with melting curve analysis 被引量:1
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作者 Yupin Tong Bonita E Lee Xiaoli L Pang 《World Journal of Virology》 2015年第4期365-371,共7页
AIM: To develop a real-time reverse transcriptionpolymerase chain reaction(RT-PCR) assay to genotype rotavirus(G and P) in Alberta from January 2012 to June 2013. METHODS: We developed and validated a different approa... AIM: To develop a real-time reverse transcriptionpolymerase chain reaction(RT-PCR) assay to genotype rotavirus(G and P) in Alberta from January 2012 to June 2013. METHODS: We developed and validated a different approach to perform rotavirus G and P genotyping using a two-step SYBR green RT-PCR(rt-g PCR) by selecting genotype-specific primers of published conventional RT nested PCR(cn RT-PCR) assay and optimizing the amplification conditions. c DNA was first synthesized from total RNA with Super Script? Ⅱ reverse transcriptase kit followed by amplication step using monoplex SYBR green real-time PCR. After the PCR reaction, melting curve analysis was used to determine specific genotype. Sixteen samples previously genotyped using cn RT-PCR were tested using the new assay and the genotyping results were compared as sensitivity analysis. Assay specificity was evaluated by testing other gastroenteritis viruses with the new assay. The amplicon size of each available genotype was determined by gelelectrophoresis and DNA sequences were obtained using Sanger-sequencing method. After validation and optimization, the new assay was used to genotype 122 pediatric clinical stool samples previously tested positive for rotavirus using electron microscopy between January2012 and June 2013.RESULTS: The new rt-g PCR assay was validated and optimized. The assay detected G1 to G4, G9, G12 and P[4] and P[8] that were available as positive controls in our laboratory. A single and clear peak of melting curve was generated for each of specific G and P genotypes with a Tm ranging from 80 ℃ to 82 ℃. The sensitivity of rt-g PCR was comparable to cn RT-PCR with 100% correlation of the 16 samples with known G and P genotypes. No cross reaction was found with other gastroenteritis viruses. Using the new rt-g PCR assay, genotypes were obtained for 121 of the 122 pediatric clinical samples tested positive for rotavirus: G1P[8](42.6%), G2P[4](4.9%), G3P[8](10.7%), G9P[8](10.7%), G9P[4](6.6%), G12P[8](23.0%), and unknown GP[8](0.8%). For the first time, G12 rotavirus strains were found in Alberta and G12 was the second most common genotype during the study period. Gel electrophoresis of all the genotypes showed expected amplicon size for each genotype. The sequence data of the two G12 samples along with other genotypes were blasted in NCBI BLAST or analyzed with Rota C Genotyping tool(http://rotac.regatools.be/). All genotyping results were confirmed to be correct.CONCLUSION: rt-g PCR is a useful tool for the genotyping and characterization of rotavirus. Monitoring of rotavirus genotypes is important for the identification of emerging strains and ongoing evaluation of rotavirus vaccination programs. 展开更多
关键词 rotavirus A Melting temperature REAL-TIME POLYMERASE chain reaction SYBR green GENOTYPING
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Autostrain RV技术联合TDI-Tei指数对肺心病患者右心室收缩功能的评估价值
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作者 王琪 温德惠 +3 位作者 李卫天 谢亚宁 刘伟亮 陆海永 《徐州医科大学学报》 CAS 2024年第3期214-218,共5页
目的 探讨右心室自动应变定量技术(Autostrain RV)联合组织多普勒(TDI)-Tei指数对慢性肺源性心脏病(CPHD)患者右心室收缩功能的评估价值。方法 根据肺动脉收缩压(PASP)将111例CPHD伴三尖瓣反流患者分为3组:A组(35~49 mmHg, 1 mmHg=0.133... 目的 探讨右心室自动应变定量技术(Autostrain RV)联合组织多普勒(TDI)-Tei指数对慢性肺源性心脏病(CPHD)患者右心室收缩功能的评估价值。方法 根据肺动脉收缩压(PASP)将111例CPHD伴三尖瓣反流患者分为3组:A组(35~49 mmHg, 1 mmHg=0.133 kPa)40例,B组(50~69 mmHg)36例,C组(≥70 mmHg)35例,纳入同期40名健康体检者作为对照组,测量4组常规超声参数及TDI-Tei指数,应用Autostrain RV技术获取右心室整体长轴应变(RV4CSL)、右心室游离壁纵向应变(RVFWSL)、游离壁基底部纵向应变(B-RVFWSL)、中部纵向应变(M-RVFWSL)及心尖部纵向应变(A-RVFWSL)数据,比较各组间差异。结果 与对照组相比,A、B、C组RV4CSL、RVFWSL、B-RVFWSL、M-RVFWSL、A-RVFWSL绝对值及三尖瓣环收缩期平面位移(TAPSE)均减小(P<0.05),且随着PASP升高依次降低,TDI-Tei指数升高(P<0.05),且随着PASP升高依次升高,组间比较差异均有统计学意义(P<0.05)。相关分析显示TDI-Tei指数与RVFWSL相关性较高(r=0.553,P<0.001)。ROC曲线显示Autostrain RV技术、TDI-Tei指数单独及联合评估右心室收缩功能的AUC均大于0.70,联合评估价值更高。结论 Autostrain RV技术能够敏感、准确地评价CPHD患者早期心肌功能障碍,联合TDI-Tei指数可进一步提高评估效能,为临床及时干预提供客观依据。 展开更多
关键词 Autostrain rv技术 组织多普勒TEI指数 肺源性心脏病 右心室功能
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基于色度分析的RV减速器健康状态评估
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作者 尚羽佳 丁露 《仪器仪表标准化与计量》 2024年第2期26-28,共3页
针对基于声发射的RV减速器运行状态监测中,声发射信号易被噪声影响,并且判别性特征难以获取的问题,本文提出了基于小波变化的声发射信号降噪方法,在此基础上提取了具有判别性特征的峭度信息,作为判断RV减速器健康状态的重要指标。
关键词 rv减速器 机器人 健康状态 状态监测
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PEDV、PoRVA和PDCoV TaqMan三重RT-qPCR检测方法的建立与初步应用
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作者 胡泽奇 李润成 +5 位作者 谭祖明 谢秀艳 王江平 秦乐娟 李荣 葛猛 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第5期2267-2272,共6页
旨在建立一种可快速同时检测猪流行性腹泻病毒(porcine epidemic diarrhea virus, PEDV)、猪A群轮状病毒(porcine rotavirus type A, PoRVA)和猪丁型冠状病毒(porcine deltacoronavirus, PDCoV)三重荧光定量PCR方法。针对PEDV-N、PoRVA-... 旨在建立一种可快速同时检测猪流行性腹泻病毒(porcine epidemic diarrhea virus, PEDV)、猪A群轮状病毒(porcine rotavirus type A, PoRVA)和猪丁型冠状病毒(porcine deltacoronavirus, PDCoV)三重荧光定量PCR方法。针对PEDV-N、PoRVA-VP6和PDCoV-M基因设计了引物和探针,条件优化后进行性能评估,并与商品化试剂盒检测对比。结果显示:本研究建立的三重RT-qPCR方法具有良好特异性,对PRRSV、PCV_2和PRV等阳性核酸不发生扩增;具有较高的敏感性,PEDV、PoRVA和PDCoV的最低检测限均达1 copies·μL^(-1);重复性良好,组内和组间变异系数均小于1%;样本适应性广,检测不同样本类型时,变异系数均小于1%。与商品化试剂盒对比,本研究建立的方法PEDV和PoRVA的检测符合率为92.5%和97.5%,并对PDCoV的检测范围更广,对其变异毒株仍有较好的检测效果。本研究建立的检测方法具有特异性好、敏感性高、稳定性强和样本适应性广等优势,为临床腹泻样本提供了一种好的检测方法。 展开更多
关键词 猪流行性腹泻病毒 猪A群轮状病毒 猪丁型冠状病毒 三重RT-qPCR
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RT-3DE联合Autostrain RV技术评价冠心病合并右冠状动脉狭窄患者右心室功能
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作者 毛荔 乔英艳 +1 位作者 李晓美 蒋珊珊 《中国动脉硬化杂志》 CAS 2024年第2期133-140,共8页
[目的]探讨实时三维超声心动图(RT-3DE)联合二维斑点追踪成像技术(2D-STI)中的右心室自动应变定量技术(Autostrain RV)评估冠心病合并右冠状动脉狭窄患者右心室功能的临床价值。[方法]收集132例疑诊为冠心病的患者,根据冠状动脉造影结... [目的]探讨实时三维超声心动图(RT-3DE)联合二维斑点追踪成像技术(2D-STI)中的右心室自动应变定量技术(Autostrain RV)评估冠心病合并右冠状动脉狭窄患者右心室功能的临床价值。[方法]收集132例疑诊为冠心病的患者,根据冠状动脉造影结果分为未发现有大于50%冠状动脉狭窄的对照组、冠心病未合并右冠状动脉狭窄组(单纯冠心病组)及冠心病合并右冠状动脉狭窄组,对三组研究对象进行常规超声测量、Autostrain RV技术分析以及RT-3DE分析。[结果]与对照组相比,单纯冠心病组、冠心病合并右冠状动脉狭窄组右心室游离壁基底段心肌纵向应变(Basal RVFWSL)、右心室游离壁中间段心肌纵向应变(Medial RVFWSL)、右心室游离壁心尖段心肌纵向应变(Apical RVFWSL)、右心室游离壁纵向应变(RVFWSL)、右心室四腔整体纵向应变(RV4CSL)、右心室射血分数(RVEF)、右心室每搏量(RVSV)及右心室每搏量指数(RVSVI)均降低,右心室收缩期末容积(RVESV)及右心室收缩期末容积指数(RVESVI)升高,差异均有统计学意义(均P<0.05);ROC曲线分析发现2D-STI各参数中RVFWSL指标以及RT-3DE各参数中RVEF指标诊断效能较高;2D-STI RVFWSL指标与RT-3DE RVEF指标联合诊断效能更高,灵敏度为90.9%,特异度为95.3%。[结论]RT-3DE联合Autostrain RV技术可提高评估冠心病合并右冠状动脉狭窄患者右心室功能损伤的准确性,为早期治疗提供依据,临床应用价值高。 展开更多
关键词 冠心病 RT-3DE Autostrain rv技术 右冠状动脉狭窄 右心室功能
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结核分枝杆菌Rv3425-16kD融合蛋白原核表达及其刺激ATB患者IFN-γ释放水平研究
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作者 史阅韩 张雪莲 +1 位作者 解宝江 贾晓炜 《临床肺科杂志》 2024年第6期915-920,共6页
目的 原核系统表达与纯化结核分枝杆菌(mycobacterium tuberculosis, MTB)融合蛋白抗原Rv3425-16kD,检测其能否被活动性结核病(active tuberculosis, ATB)中肺结核患者和结核潜伏性感染(latent TB infection, LTBI)者外周血单个核细胞(p... 目的 原核系统表达与纯化结核分枝杆菌(mycobacterium tuberculosis, MTB)融合蛋白抗原Rv3425-16kD,检测其能否被活动性结核病(active tuberculosis, ATB)中肺结核患者和结核潜伏性感染(latent TB infection, LTBI)者外周血单个核细胞(peripheral blood mononuclear cells, PBMCs)识别,探讨作为诊断抗原鉴别活动性结核感染的可行性。方法 利用原核表达系统表达融合蛋白Rv3425-16kD并进行亲和纯化,以Western Blot法鉴定;收集结核病医学部收治的的ATB患者、LTBI者和健康人外周血,分离PBMCs,分别用Rv3425-16kD融合蛋白、早期分泌靶抗原6/培养液蛋白10(ESAT-6/CFP10)和MTB全菌裂解液刺激后,提取细胞总RNA,荧光定量PCR方法检测γ-干扰素(Interferon-γ,INF-γ) mRNA的表达,通过t检验分析刺激前后PBMCs IFN-γ mRNA的表达差异。结果 原核系统表达及纯化的Rv3425-16kD融合蛋白相对分子质量均为37kD。健康人PBMCs刺激前,IFN-γ mRNA表达量为4.2±1.6,MTB全菌裂解液刺激后为14.7±3.5,差异具有统计学意义(P<0.001),另外两组刺激没有明显变化;ATB患者PBMCs刺激前,IFN-γ mRNA表达量为3.7±1.2,经Rv3425-16kD融合蛋白、ESAT-6/CFP10抗原多肽和H37Rv全菌裂解液分别刺激后IFN-γ mRNA表达量为:166.0±29.7、13.7±5.8和213.0±33.5,三组抗原在刺激前后IFN-γ mRNA表达量差异均具有统计学意义(P<0.001)。结论 原核重组的Rv3425-16kD融合蛋白可被ATB患者PBMCs细胞识别,具有较强抗原刺激作用和特异性,可用作MTB感染的预防及诊断。 展开更多
关键词 结核分枝杆菌 rv3425-16kD融合蛋白 外周血单个核细胞 Γ-干扰素
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一种未知转速下的RV减速器故障诊断方法
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作者 唐靖 林长鹏 +2 位作者 柳景 兰江 韦开湘 《中北大学学报(自然科学版)》 CAS 2024年第1期22-29,共8页
随着制造业的快速发展,工业机器人已经成为智能制造的核心执行单元。针对旋转矢量(Rotary vector,RV)减速器在运行过程中转速时变、瞬时转速不易被读取的问题,提出一种基于电流信号和振动信号的RV减速器健康状态评估方法。基于电流信号... 随着制造业的快速发展,工业机器人已经成为智能制造的核心执行单元。针对旋转矢量(Rotary vector,RV)减速器在运行过程中转速时变、瞬时转速不易被读取的问题,提出一种基于电流信号和振动信号的RV减速器健康状态评估方法。基于电流信号的瞬时频率获取输入转频信息,计算得出减速器组成部件的故障特征频率;同步截取平稳振动信号,再利用粒子寻优的变分模态分解算法对提取出来的振动特征进行分解,并基于多维评价函数选取故障敏感分量进行包络分析,以挖掘故障信息进而评估其健康状态。最后,通过实验数据集验证该方法的有效性。结果表明,本文所提方法可以获得工业机器人在作业时的关节输入转速,同时,多维评价函数可以从RV减速器信号中提取富含冲击信息的故障敏感分量。 展开更多
关键词 未知转速 工业机器人 旋转矢量(Rotary vector rv)减速器 故障诊断 多维评价函数
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基于改进NSGA-Ⅱ算法的RV减速器参数多目标优化研究
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作者 杨昊霖 王茹芸 +2 位作者 罗利敏 贡林欢 楼应侯 《机电工程》 CAS 北大核心 2024年第4期651-658,共8页
旋转矢量(RV)减速器是工业机器人核心部件,对于机器人的性能起到关键作用。针对提升RV减速器综合性能的问题,从优化传动压力角的相关参数出发,对其结构参数(摆线轮齿数、短幅系数、针径系数、摆线轮宽度等)的多目标优化设计进行了研究... 旋转矢量(RV)减速器是工业机器人核心部件,对于机器人的性能起到关键作用。针对提升RV减速器综合性能的问题,从优化传动压力角的相关参数出发,对其结构参数(摆线轮齿数、短幅系数、针径系数、摆线轮宽度等)的多目标优化设计进行了研究。首先,研究了摆线轮平均压力角、传动效率和传动机构体积三者的相关参数之间的关系;然后,以此为优化目标,在摆线轮标准齿廓方程的基础上建立了多目标优化数学模型(该模型采用了基于非支配占优排序遗传学算法(NSGA-Ⅱ)改进了交叉算子系数生成的改进NSGA-Ⅱ算法);通过模型求解得到了帕累托最优解集,根据模糊集合理论的相关方法选取了最优解;最后,以某公司220-BX型RV减速器为例,进行了优化设计,建立了3D模型后进行了有限元分析,并加工出实验样机,进行了传动效率对比实验。实验结果表明:摆线轮平均压力角减小了7.19%,体积减小了11.1%,传动效率提高了4.9%。研究结果表明:该模型交互性强,能提高设计效率并节省设计开销,可为实际RV减速器工程优化设计提供参考。 展开更多
关键词 机械传动 旋转矢量(rv)减速器 改进非支配占优排序遗传学算法(NSGA-Ⅱ) 多目标优化 平均传动压力角 传动效率
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