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高能电子束电磁透镜的研究进展 被引量:4
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作者 唐腾飞 刘海浪 +4 位作者 岳高 唐杰 宁蔚 刘坤明 骆玉城 《真空科学与技术学报》 EI CAS CSCD 北大核心 2022年第10期719-725,共7页
在电子束加工设备中,聚焦系统和偏转系统是决定电子枪性能的关键因素。介绍了电子束聚焦、偏转技术的原理和特点,归纳整理了电磁透镜结构的优化结果、电子束聚焦规律以及减小束斑像差控制等方面所取得的研究进展。分析了目前电磁透镜控... 在电子束加工设备中,聚焦系统和偏转系统是决定电子枪性能的关键因素。介绍了电子束聚焦、偏转技术的原理和特点,归纳整理了电磁透镜结构的优化结果、电子束聚焦规律以及减小束斑像差控制等方面所取得的研究进展。分析了目前电磁透镜控制电子束加工中存在的不足,并对未来电子枪发展趋势做出了展望。 展开更多
关键词 电子束 聚焦系统 偏转系统 电磁透镜 束斑像差
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老年患者术中每搏变异度指导液体治疗对肾功能的影响
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作者 孙涛 王涛 +2 位作者 刘欢 高月 李利彪 《中国肿瘤临床》 CAS CSCD 北大核心 2023年第24期1259-1264,共6页
目的:探讨老年患者在硬膜外联合全身麻醉下实施腹腔镜结直肠癌根治术,术中使用每搏变异度(stroke volume variation,SVV)指导液体治疗对肾功能的影响。方法:前瞻性选取内蒙古医科大学附属医院100例老年患者在硬膜外联合全身麻醉下行腹... 目的:探讨老年患者在硬膜外联合全身麻醉下实施腹腔镜结直肠癌根治术,术中使用每搏变异度(stroke volume variation,SVV)指导液体治疗对肾功能的影响。方法:前瞻性选取内蒙古医科大学附属医院100例老年患者在硬膜外联合全身麻醉下行腹腔镜结直肠癌根治术,随机分为对照组(C组)和试验组(S组),每组50例。C组采用常规补液法,S组在SVV指导下行液体补液。评估比较两组患者术前、术后血清肌酐(serum creatinine,Scr)、血尿素氮(blood urea nitrogen,BUN)、中性粒细胞明胶酶相关脂钙蛋白(neutrophil gelatinase-associated lipocalin protein,NGAL)、肾损伤分子-1(kidney injury molecule-1,KIM-1)。结果:S组术后2 h、24 h的NGAL浓度均较C组降低(P=0.033,P=0.014)。S组术后24 h的KIM-1明显低于C组(P=0.012)。S组术后1天Scr明显低于C组(P=0.049)。C组术后急性肾损伤(acute kidney injury,AKI)发生率显著高于S组(P=0.027)。结论:老年患者腹腔镜结直肠癌根治术中,使用SVV指导液体治疗,可降低术后血清中肾损伤标记物浓度及术后AKI的发生率,对肾功能有保护作用。 展开更多
关键词 每搏变异度 液体治疗 硬膜外联合全麻 急性肾损伤 老年患者
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Transcriptional regulation effect of constituents in Polygonum multiflorum Thunb. based on human progesterone X receptor(hPXR) mediated CYP3A4 rapid screening system
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作者 Zhao-yan ZHANG Yu-guang WANG yue gao 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期339-340,共2页
OBJECTIVE This study investigated transcriptional regulation of the main chemical con.stituents of Polygonum multiflorum Thunb.including Stilbene Glucoside(THSG) and anthraquinone constituents(Emodin,Rhein,Aloeemodin,... OBJECTIVE This study investigated transcriptional regulation of the main chemical con.stituents of Polygonum multiflorum Thunb.including Stilbene Glucoside(THSG) and anthraquinone constituents(Emodin,Rhein,Aloeemodin,Chrysophanol and Physcion) and six potential liver injury constituents(gallic acid,quercetin,luteolin,kaempferol,resveratrol) on mediated by PXR CYP3A4.Early establishment of pregnane X receptor mediated CYP3A4 drug induced rapid screening technique was used to determine the effects of these constituents.METHODS First,effect of constituents on the cell activity was detected by MTS cell viability assay.IC50 was calculated.Second,the expression vector and reporter vector were co-transfected into Hep G2 cells,10 μmol·L^(-1) Rifampicin as a positive control,10 μmol·L^(-1) Ketoconazole as a negative control.After treated with different concentrations of(the an.thraquinone constituents concentrations were 2.5,5 and 10 μmol·L^(-1);the concentrations of Gallic Acid,Quercetin,Luteolin,Kaempferol,Apigenin,Resveratrol concentrations were 5,10 and 20 μmol·L^(-1)) for24 h,the cells were tested for dual luciferase activity.RESULTS The results show that the inhibitory ef.fect of THSG,Chrysophanol,Emodin,Rhein and Aloeemodin on CYP3A4 was inhibited by co-transfec.tion of pcDNA3.1 and pGL4.17-CYP3A4.The expression of pcDNA3.14-PXR and pGL4.17-CYP3A4 was induced by the four constituents.Besides,Emodin has a directly inducing effect.Four anthraqui.none constituentscan induce the effect of CYP3A4 by PXR,but Emodin can directly induce CYP3A4.THSG can inhibit CYP3A4,but in the presence of PXR plasmid can induce CYP3A4.For the six poten.tial liver injury constituents,results show that the plasmid pcDNA3.1 was cotransfected with pGL4.17-CYP3A4 regulation of Gallic Acid and Resveratrol on CYP3A4 inhibitory effects of Quercetin,Luteolin,Kaempferol have an induce effect;after pcDNA3.14-PXR and pGL4.17-CYP3A4 cotransfected,Quercetin,Luteolin,Kaempferol,Apigenin,Resveratrol have induced effect,three constituents' induc.tion effect had significant difference.CONCLUSION 12 kinds of Polygonum multiflorum Thunb.constit.uents have inhibitory or activating effects on CYP3A4,after the participation of PXR,9 components have induced effects on CYP3A4,and the induction effect of 6 components has significant difference.The results suggested that we should pay attention to potential drug interactions when combined with Polygonum multiflorum Thunb.,and improve safety and efficacy. 展开更多
关键词 何首乌 肝损伤 治疗方法 临床分析
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Object detection based on combination of local and spatial information
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作者 Qinkun Xiao Nan Zhang +1 位作者 Fei Li yue gao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期715-720,共6页
A method of object detection based on combination of local and spatial information is proposed. Firstly, the categorygiven representative images are chosen through clustering to be templates, and the local and spatial... A method of object detection based on combination of local and spatial information is proposed. Firstly, the categorygiven representative images are chosen through clustering to be templates, and the local and spatial information of template are ex- tracted and generalized as the template feature. At the same time, the codebook dictionary of local contour is also built up. Secondly, based on the codebook dictionary, sliding-window mechanism and the vote algorithm are used to select initial candidate object win- dows. Lastly, the final object windows are got from initial candidate windows based on local and spatial structure feature matching. Experimental results demonstrate that the proposed approach is able to consistently identify and accurately detect the objects with better performance than the existing methods. 展开更多
关键词 object detection codebook dictionary spatial matching local contour matching.
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Lesch-Nyhan综合征家兔模型的建立及其表型分析
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作者 资崯 郑淑文 +6 位作者 宁丽 蔺紫怡 鹿璇 席嘉慧 高月 周小青 唐成程 《遗传》 CAS CSCD 北大核心 2024年第5期408-420,共13页
Lesch-Nyhan综合征(Lesch-Nyhan syndrome,LNS)是一种先天性的嘌呤代谢缺陷病,次黄嘌呤鸟嘌呤磷酸核糖转移酶(hypoxanthine phosphoribosyltransferase,HPRT)是其主要致病基因,临床特征表现为尿酸分泌过多、痛风、肾结石及肾脏损伤等,... Lesch-Nyhan综合征(Lesch-Nyhan syndrome,LNS)是一种先天性的嘌呤代谢缺陷病,次黄嘌呤鸟嘌呤磷酸核糖转移酶(hypoxanthine phosphoribosyltransferase,HPRT)是其主要致病基因,临床特征表现为尿酸分泌过多、痛风、肾结石及肾脏损伤等,目前致病机制尚未被完全阐明且无有效治愈手段。动物模型在疾病致病机理研究和治疗方式探索中发挥着重要功能。本研究采用高效的CRISPR/Cas9基因编辑技术和显微注射的方式敲除家兔(Oryctolagus cuniculus)HPRT基因建立了LNS家兔模型,以期能更好的模拟该疾病的表型。首先针对兔HPRT基因第3外显子设计一条sgRNA,将体外转录的sgRNA和Cas9 mRNA共注射到兔受精卵中,注射后的胚胎移植到代孕母兔子宫中,待仔兔出生后对其基因型及表型进行鉴定与分析。共出生4只仔兔(分别编号为R1、R2、R3和R4),测序结果显示4只仔兔都产生了不同程度的基因修饰,基因编辑效率达100%,其中R4仔兔T载体测序结果在基因编辑靶点未检测到野生型序列。通过6-硫代鸟嘌呤(6-Thioguanine,6-TG)药物测试,证明R4仔兔HPRT酶活性缺失;肾组织HE染色发现4只仔兔表现出肾小球炎细胞浸润、集合管脱落等肾脏损失。本研究成功设计了1条能够敲除家兔HPRT基因的sgRNA,并采用CRISPR/Cas9基因编辑技术和显微注射方式成功构建了HPRT基因修饰家兔,为研究LNS综合征致病机制和治疗方式提供了新的非啮齿类动物模型。 展开更多
关键词 Lesch-Nyhan综合征 HPRT 家兔
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