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Pathological axonal enlargement in connection with amyloidosis,lysosome destabilization,and bleeding is a major defect in Alzheimer’s disease 被引量:1
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作者 Hualin Fu Jilong Li +4 位作者 Chunlei Zhang Guo Gao Qiqi Ge Xinping Guan Daxiang Cui 《Neural Regeneration Research》 2026年第2期790-799,共10页
Alzheimer’s disease is a multi-amyloidosis disease characterized by amyloid-βdeposits in brain blood vessels,microaneurysms,and senile plaques.How amyloid-βdeposition affects axon pathology has not been examined ex... Alzheimer’s disease is a multi-amyloidosis disease characterized by amyloid-βdeposits in brain blood vessels,microaneurysms,and senile plaques.How amyloid-βdeposition affects axon pathology has not been examined extensively.We used immunohistochemistry and immunofluorescence staining to analyze the forebrain tissue slices of Alzheimer’s disease patients.Widespread axonal amyloidosis with distinctive axonal enlargement was observed in patients with Alzheimer’s disease.On average,amyloid-β-positive axon diameters in Alzheimer’s disease brains were 1.72 times those of control brain axons.Furthermore,axonal amyloidosis was associated with microtubule-associated protein 2 reduction,tau phosphorylation,lysosome destabilization,and several blood-related markers,such as apolipoprotein E,alpha-hemoglobin,glycosylated hemoglobin type A1C,and hemin.Lysosome destabilization in Alzheimer’s disease was also clearly identified in the neuronal soma,where it was associated with the co-expression of amyloid-β,Cathepsin D,alpha-hemoglobin,actin alpha 2,and collagen type IV.This suggests that exogenous hemorrhagic protein intake influences neural lysosome stability.Additionally,the data showed that amyloid-β-containing lysosomes were 2.23 times larger than control lysosomes.Furthermore,under rare conditions,axonal breakages were observed,which likely resulted in Wallerian degeneration.In summary,axonal enlargement associated with amyloidosis,micro-bleeding,and lysosome destabilization is a major defect in patients with Alzheimer’s disease.This finding suggests that,in addition to the well-documented neural soma and synaptic damage,axonal damage is a key component of neuronal defects in Alzheimer’s disease. 展开更多
关键词 Alzheimer’s disease amyloid-β AMYLOIDOSIS axonal enlargement hemoglobin hemorrhage lysosome destabilization neuropil thread tau Wallerian degeneration
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拟缺香茶菜水提物显著改善肿瘤细胞荧光成像分辨率
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作者 郑然 刘馨慧 +2 位作者 林平昊 侯欣艺 黄华 《生命科学研究》 2026年第1期53-62,共10页
荧光成像分析是生物医学领域中用于研究目的蛋白亚细胞定位及蛋白质相互作用的常用手段,但很多模式细胞的荧光成像效果不佳,其成像分辨率提升受限于细胞的自身厚度和体积。膨胀显微成像是解决此问题的技术手段之一,但现有方法操作复杂... 荧光成像分析是生物医学领域中用于研究目的蛋白亚细胞定位及蛋白质相互作用的常用手段,但很多模式细胞的荧光成像效果不佳,其成像分辨率提升受限于细胞的自身厚度和体积。膨胀显微成像是解决此问题的技术手段之一,但现有方法操作复杂、稳定性差且对免疫荧光抗体的浓度要求较高。笔者团队在前期研究中发现,拟缺香茶菜的分离提取物Reniformin A对肿瘤细胞有放大作用。基于上述背景,本研究旨在探索低成本且操作便捷的提升荧光成像分辨率的方法。首先,考察了不同质量浓度及不同处理时间下,拟缺香茶菜水提物对A549、MDA-MB-231和HeLa 3种肿瘤细胞的影响,结果显示:拟缺香茶菜水提物对A549和MDA-MB-231细胞有显著的体积放大作用,且能有效提高荧光成像分辨率,其最佳处理时间和质量浓度分别为24 h和8 mg/m L;同时,拟缺香茶菜水提物对HeLa细胞无显著放大效果,提示其作用具有细胞特异性。随后,对关键细胞器及细胞骨架进行了形态学分析,结果显示,拟缺香茶菜水提物并不影响A549和MDA-MB-231细胞的基本骨架结构(α-tubulin、F-actin)及关键细胞器(溶酶体、线粒体)的形态和分布特性。接下来,以A549细胞为模型,用已知定位信息的3个蛋白质(METTL6、SLC38A7和MYH9)进行了亚细胞定位验证,结果显示,拟缺香茶菜水提物处理没有改变3个蛋白质的原有定位特性,且没有引发非特异性共定位现象。最后,以A549细胞为模型,通过免疫荧光实验初步探究了拟缺香茶菜水提物提升肿瘤细胞荧光成像分辨率的潜在机制,推测拟缺香茶菜水提物可能是通过增强整合素功能、稳定黏着斑、优化黏着斑动态,进而为细胞体积增大提供更好的支撑作用。以上结果表明:高质量浓度(8 mg/m L)拟缺香茶菜水提物对部分肿瘤细胞有放大效应,可有效提升荧光成像分析的便利度和分辨率,且不影响原有细胞结构的形态及分布特性,未来具有较大的应用前景和进一步开发价值。 展开更多
关键词 拟缺香茶菜 肿瘤细胞 放大效应 荧光成像 分布特性
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扩孔方法对纳米梯级孔β分子筛催化剂烷基化性能的影响
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作者 时雅滨 李翠钦 +1 位作者 田明 王瑞雨 《分子催化(中英文)》 北大核心 2026年第1期34-43,I0002,共11页
C4烃类和FCC汽油进行烷基化反应是生产高辛烷值清洁汽油的有效途径.纳米梯级孔β分子筛可明显提升催化剂的活性,增强反应物的扩散能力,延长催化剂使用寿命,但是制备过程中却存在结晶度低、工艺条件不稳定、易产生杂峰等问题.因此如何制... C4烃类和FCC汽油进行烷基化反应是生产高辛烷值清洁汽油的有效途径.纳米梯级孔β分子筛可明显提升催化剂的活性,增强反应物的扩散能力,延长催化剂使用寿命,但是制备过程中却存在结晶度低、工艺条件不稳定、易产生杂峰等问题.因此如何制备介孔尺寸较大且热稳定性高的纳米梯级孔β分子筛成为研究热点.为了解决上述问题,本文采用融硅法、物理扩孔法和化学扩孔法制备纳米梯级孔β分子筛,在设定条件(90℃、2 MPa、氢油体积比为10、空速为2h^(-1))下对催化剂烷基化反应性能完成系统评估,并采用低温氮气吸附-脱附测试、扫描电子显微镜(SEM)和X射线衍射(XRD)等技术手段,系统的对样品的物理化学特性进行了考察.结果表明,β分子筛晶型在融硅法过程中受到损害,物理扩孔法未能对催化剂的催化性能进行改善,而经过化学扩孔法处理的β分子筛在XRD谱图中形成特征峰,且具有良好的晶型,颗粒尺寸一致性高,扩孔效果提升显著,烷基化性能优异,因此化学扩孔法更适用于制备纳米梯级孔β分子筛. 展开更多
关键词 Β分子筛 烷基化 融硅法 物理扩孔法 化学扩孔法
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基于FPGA实现的改进误差补偿图像放大算法研究
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作者 万子荣 张彩珍 《计算机工程与科学》 北大核心 2026年第3期467-475,共9页
为了尽可能地保持边缘信息,提高图像放大后的视觉效果,提出一种基于FPGA实现的改进误差补偿图像放大算法。该算法基于误差补偿理论,在对每个像素点进行误差补偿修正的基础上,增加了引导滤波。利用误差补偿后的图像作为引导滤波的引导图... 为了尽可能地保持边缘信息,提高图像放大后的视觉效果,提出一种基于FPGA实现的改进误差补偿图像放大算法。该算法基于误差补偿理论,在对每个像素点进行误差补偿修正的基础上,增加了引导滤波。利用误差补偿后的图像作为引导滤波的引导图像和输入图像以保留更多的边缘信息,调整像素的权重并将参数ε设置为0.1。采用峰值信噪比PSNR、均值梯度和梯度标准差,对改进算法及双线性误差补偿算法进行了实验研究对比分析。研究结果表明,改进算法将图像的PSNR增加了3~9 dB,均值梯度减小了9~36,梯度标准差减少了8~26,可以有效改善图像边缘失真的情况。 展开更多
关键词 图像放大 误差补偿 FPGA 引导滤波 边缘失真
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A case report with the progression from atrial fibrillation to complete AV block, heart failure and electrical storm
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作者 Shi-Xing LI Xiang-Min SHI +1 位作者 Jian LI Chuang ZHANG 《Journal of Geriatric Cardiology》 2026年第1期65-68,共4页
When patients initially present with atrial fibrillation along with an enlarged heart and heart failure, followed by atrioventricular block, it's essential to consider genetic factors.^([1])Genetic testing can off... When patients initially present with atrial fibrillation along with an enlarged heart and heart failure, followed by atrioventricular block, it's essential to consider genetic factors.^([1])Genetic testing can offer crucial diagnostic evidence, aiding in prognosis assessment and the adoption of appropriate treatment strategies. 展开更多
关键词 heart failure atrial fibrillation enlarged heart atrioventricular block genetic factors genetic testing adoption appropriate treatment strategies complete av block prognosis assessment
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突扩跌坎式掺气减蚀设施水力特性研究
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作者 赵歆萌 刘亚坤 +1 位作者 张帝 卢洋亮 《中国农村水利水电》 北大核心 2026年第3期134-139,147,共7页
针对高水头、大流量的泄洪洞有压段出口易出现空化空蚀问题,依托长度比尺为1∶50的物理模型试验对窄缝消能的突扩跌坎式掺气设施水力特性进行研究;并借助Fluent软件探究不同体型参数下的水力特性规律,数值模拟采取VOF多相流模型、RNG k... 针对高水头、大流量的泄洪洞有压段出口易出现空化空蚀问题,依托长度比尺为1∶50的物理模型试验对窄缝消能的突扩跌坎式掺气设施水力特性进行研究;并借助Fluent软件探究不同体型参数下的水力特性规律,数值模拟采取VOF多相流模型、RNG k-ε湍流模型、PISO速度压力耦合方程,得出的流量、水面线、流速和时均压强分布与试验实测值最大误差低于10%,可满足工程精度要求。进一步深入研究发现:随着闸门开度减小、出口窄缝宽度增加,侧壁对水流约束降低,纵向拉伸减弱,空腔长度、净空腔长度及净空腔高度均有所增加,且高水位下的各项空腔水力学指标增加趋势大于低水位;其他条件不变时,空腔回水相比射流落点对窄缝收缩比的变化更敏感;随着侧壁由对称收缩逐渐偏转至单侧收缩,最长射流落点位置不变,由侧壁中心逐渐偏转至不收缩侧,且净空腔高度保持不变;采取增大窄缝收缩比及底板坡度的方法可较好解决空腔回水问题。该研究有助于明晰采用窄缝消能的泄洪洞掺气减蚀设施的三维水力学特性,可为相关工程掺气减蚀设计提供借鉴。 展开更多
关键词 高速水流 掺气减蚀 突扩跌坎 空腔回水 窄缝消能
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Y形切口主动脉根部扩大术治疗小主动脉瓣环患者2例
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作者 李燚 唐龙 +1 位作者 张永恒 刘建平 《中国实用医药》 2026年第1期135-139,共5页
心脏瓣膜病是一类常见心血管外科疾病,其病因较为复杂,患者随病情进展可能逐渐出现右心衰竭和(或)左心衰竭等症状,严重的主动脉瓣狭窄或反流甚至有猝死的风险。目前临床上诊断和评估心脏瓣膜病主要依靠超声心动图。外科主动脉瓣置换术... 心脏瓣膜病是一类常见心血管外科疾病,其病因较为复杂,患者随病情进展可能逐渐出现右心衰竭和(或)左心衰竭等症状,严重的主动脉瓣狭窄或反流甚至有猝死的风险。目前临床上诊断和评估心脏瓣膜病主要依靠超声心动图。外科主动脉瓣置换术是临床上治疗主动脉瓣病变的经典术式,但对于小主动脉瓣环患者,在置换瓣膜时往往需要同时扩大主动脉根部,便于植入更大型号的瓣膜,改善患者血流动力学和远期生活质量。当前国际上已有多种主动脉根部扩大术式应用于小主动脉瓣环患者的外科治疗,但各有优劣。本文报道了通过Y形切口主动脉根部扩大术成功治疗2例小主动脉瓣环患者,该技术安全性高、效果显著,为临床上类似患者治疗方案的选择提供了参考依据。 展开更多
关键词 心脏瓣膜病 小主动脉瓣环 主动脉瓣置换术 Y形切口 主动脉根部扩大术
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超高性能混凝土(UHPC)加固古石拱桥的力学性能有限元分析 被引量:1
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作者 张瀚升 曹三鹏 +2 位作者 亓兴军 王福祥 赵若帆 《混凝土与水泥制品》 2026年第1期81-85,共5页
为了改善古石拱桥因长期服役累积损伤所引起的整体承载能力降低问题,采用增大截面法对某现存服役古石拱桥的主拱圈底部进行加固,并建立了有限元计算模型,通过承载力富裕量、挠度、弹性屈曲稳定系数等指标,对比分析了C50混凝土和超高性... 为了改善古石拱桥因长期服役累积损伤所引起的整体承载能力降低问题,采用增大截面法对某现存服役古石拱桥的主拱圈底部进行加固,并建立了有限元计算模型,通过承载力富裕量、挠度、弹性屈曲稳定系数等指标,对比分析了C50混凝土和超高性能混凝土(Ultra-high performance concrete,UHPC)的加固效果。结果表明:采用C50混凝土和UHPC加固均可以有效提高古石拱桥的承载能力和稳定性,减小挠度;与C50混凝土相比,UHPC的加固效果更好。 展开更多
关键词 古石拱桥 增大截面法 超高性能混凝土(UHPC) 承载能力 挠度 稳定性 有限元分析
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急诊重度EPVSs急性脑梗死患者预后不良风险列线图预测模型的构建及临床意义
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作者 韩明明 唐秀丽 韩咪 《河北医学》 2026年第1期105-112,共8页
目的:通过分析影响急诊重度血管周围间隙扩大(EPVSs)急性脑梗死(ACI)患者预后不良的影响因素,构建风险列线图预测模型,并分析其临床指导意义。方法:前瞻性选择2021年1月至2024年11月急诊收治的300例重度EPVSs ACI患者为研究对象,根据7∶... 目的:通过分析影响急诊重度血管周围间隙扩大(EPVSs)急性脑梗死(ACI)患者预后不良的影响因素,构建风险列线图预测模型,并分析其临床指导意义。方法:前瞻性选择2021年1月至2024年11月急诊收治的300例重度EPVSs ACI患者为研究对象,根据7∶3的比例分为建模集(n=210)和验证集(n=90),根据改良Rankin量表评分将建模集分为预后良好组(0~2分,n=127)和预后不良组(3~6分,n=83)。收集ACI患者入院时基本信息、临床病史等一般资料并检测相关实验室指标。多因素Logistic回归分析急诊重度EPVSs的ACI患者预后不良的影响因素,并应用rms程序包构建列线图预测模型;ROC曲线评估模型的预测效能;校准曲线评估模型预测概率与观察结果之间的一致性;决策曲线评估模型的净收益。结果:建模集和验证集预后不良率为分别39.52%、35.56%;建模集预后不良组年龄≥65岁、梗死部位为关键脑区、高血压、脑白质疏松占比及美国国立卫生研究院卒中量表(NIHSS)、梗死面积、EPVSs数量、超敏C反应蛋白(hs-CRP)高于预后良好组(均P<0.05);年龄(≥65岁)、高血压(是)及NIHSS评分、梗死面积、EPVSs数量增加是急诊重度EPVSs的ACI患者预后不良的独立危险因素(P<0.05);基于多因素Logistic回归分析结果构建列线图预测模型,建模集和验证集ROC曲线的AUC分别为0.810(95%CI:0.750~0.860)、0.802(95%CI:0.741~0.853);两组预测曲线与实际曲线拟合良好;决策曲线分析阈值概率均大于0。结论:年龄、高血压、NIHSS评分、梗死面积、EPVSs数量是急诊重度EPVSs的ACI患者预后不良的独立影响因素,基于该结果构建的列线图预测模型具有较高的预测效能,为临床预后评估及个性化治疗提供有效参考。 展开更多
关键词 急性脑梗死 血管周围间隙扩大 预测模型
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闪速浮选技术研究及应用进展
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作者 张福亚 张跃军 +1 位作者 樊学赛 张明 《有色金属(中英文)》 北大核心 2026年第1期90-97,共8页
闪速浮选技术是一种应用在磨矿分级回路分选分级沉砂的选矿技术,对于减少目的矿物过磨,实现能收早收具有重要意义。本文归纳总结了闪速浮选技术适用的矿石工艺条件以及影响闪速浮选效果的因素,并介绍了近些年来闪速适用矿种的扩展情况... 闪速浮选技术是一种应用在磨矿分级回路分选分级沉砂的选矿技术,对于减少目的矿物过磨,实现能收早收具有重要意义。本文归纳总结了闪速浮选技术适用的矿石工艺条件以及影响闪速浮选效果的因素,并介绍了近些年来闪速适用矿种的扩展情况以及闪速浮选试验方法的研究进展。然后总结了闪速浮选装备方面的研究和应用进展,其中矿冶集团开发的YX系列闪速浮选机是目前工业应用最广泛的闪速浮选设备。最后提出了随着矿山规模的增加以及矿石性质的差异化,大型化和专属化是闪速浮选装备的发展方向。随着矿产资源的不断开发,闪速浮选技术具有非常广阔的应用前景。 展开更多
关键词 闪速浮选 试验方法 设备 大型化
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基于剪切速率与涡结构协同调控的TBK高剪切调浆机放大研究
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作者 孙伟成 张福亚 +3 位作者 李红帅 张明 王青芬 段莉莉 《有色金属(选矿部分)》 2026年第2期95-101,共7页
针对微细粒矿物浮选前高剪切调浆过程,解决实验室小型设备向工业大型设备放大时存在的“放大效应”问题,旨在确定科学可靠的放大准则。以TBK1015型高剪切调浆机为标准机型,遵循几何相似原则(放大倍数k=2),应用搅拌雷诺数(Re)、弗劳德数(... 针对微细粒矿物浮选前高剪切调浆过程,解决实验室小型设备向工业大型设备放大时存在的“放大效应”问题,旨在确定科学可靠的放大准则。以TBK1015型高剪切调浆机为标准机型,遵循几何相似原则(放大倍数k=2),应用搅拌雷诺数(Re)、弗劳德数(Fr)、韦伯数(We)、单位体积输入功(P/V)及科莫尺度剪切速率(γ)五种动力相似准则计算放大后机型(TBK2030)的操作转速。采用计算流体力学(CFD)方法,对比分析不同准则下的流场特性、剪切速率分布及涡流结构。模拟结果表明,不同放大准则对流场剪切强度影响显著。其中,等科莫尺度剪切速率准则计算出的转速(107 r/min)能使放大后的设备在叶轮区及全槽范围内维持与标准机型(180 r/min)相近的剪切速率分布和涡流强度,最大局部剪切速率300 s^(-1),流体速度从叶轮通过涡流传递到槽体边壁下降幅度不超过80%。相比之下,等雷诺数和等韦伯数准则导致剪切不足,而等弗劳德数准则则可能造成过度剪切,等科莫尺度剪切速率准则在保证微细粒矿物表面活化与药剂分散效果的同时,兼顾了能耗经济性,是高剪切调浆机工业放大的优选方案。 展开更多
关键词 剪切 分散 放大 设备大型化 流体力学 仿真 多相流 黄铁矿
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基于扩孔竖井掘进机开挖工法的锥形刀盘设计与试验
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作者 徐光亿 齐志冲 +4 位作者 赵子辉 贾涛 李明 吴浩 耿麒 《隧道建设(中英文)》 北大核心 2026年第1期194-203,共10页
为实现扩孔竖井掘进机的全断面机械开挖,提升整机掘进效率,基于平面刀盘设计理论并结合扩孔竖井下部排渣工法,研制一种扩孔竖井锥形刀盘。首先,介绍扩孔竖井的开挖工法、整机组成及排渣原理,并采用数值模拟方法对比分析4种不同先导井直... 为实现扩孔竖井掘进机的全断面机械开挖,提升整机掘进效率,基于平面刀盘设计理论并结合扩孔竖井下部排渣工法,研制一种扩孔竖井锥形刀盘。首先,介绍扩孔竖井的开挖工法、整机组成及排渣原理,并采用数值模拟方法对比分析4种不同先导井直径(2000、1600、1200、800 mm)下的下排渣溜渣效率;然后,基于平面刀盘设计理论对锥形刀盘刀间距、刀具布置、刀具选型、刀座结构、本体结构形式等进行设计;最后,依托某试验场地开展开挖掘进试验,对扩孔竖井锥形刀盘的实用性进行现场试验验证。由研究结果可得:1)先导井直径建议≥1200 mm;2)锥形刀盘的整体结构设计及结构强度合理、运用可行;3)在45°锥度下刀具受力满足使用要求;4)试验过程中刀盘较好地完成了锥面破岩,满足扩孔竖井掘进机开挖、出渣等工序的施工需求,实现了扩孔竖井掘进机的机械化和自动化作业。 展开更多
关键词 扩孔竖井掘进机 锥形刀盘 刀具 先导井 下排渣
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Risk factors of distal segment aortic enlargement after complicated type B aortic dissection 被引量:8
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作者 Yu Shen Simeng Zhang +4 位作者 Guanglang Zhu Yanqing Chen Zheng Chen Zaiping Jing Qingsheng Lu 《Journal of Interventional Medicine》 2019年第4期154-159,共6页
Objectives:Distal segment aortic enlargement(DSAE)is a common complication that influences the long-term prognosis of type B aortic dissection(TBAD)after thoracic endovascular aortic repair(TEVAR).In this study,a mult... Objectives:Distal segment aortic enlargement(DSAE)is a common complication that influences the long-term prognosis of type B aortic dissection(TBAD)after thoracic endovascular aortic repair(TEVAR).In this study,a multivariate analysis was performed to find potential factors predictive of DSAE.Methods:A single-center retrospective study was performed from 1999 to 2016.Included in the study were complicated TBAD patients who underwent TEVAR with uncovered residual tears.Based on the diameter of the distal segment of the uncovered aorta,we assigned patients to an enlargement group and a non-enlargement group.Data extracted from the medical records included demographic and clinical characteristics and followup computed tomography angiography data.The primary endpoints were the all-cause mortality and the presumably aortic-related events that required reintervention during the follow-up period.Results:For the 333 patients,all-cause mortality was 38(11.41%),and 76(22.82%)patients underwent reintervention.A total of 70(21.02%)patients experienced DSAE,among them were 2 patients who died of aortic rupture and 58 patients who accepted reintervention.Multivariate analysis reviewed independent risk factors of postoperative DSAE,including current smoking,the residual length of the patent false lumen,the postoperative number of dissection tears in the thoracic aorta and type III aortic arch;as well as protective factors,including the application of a restrictive bare stent(RBS),the length of covered stent in the descending thoracic aorta,and the distance from the residual first tear to the left subclavian artery(LSA).Conclusion:DSAE after TEVAR for patients with a complicated TBAD can be influenced by their current smoking habit,the residual length of patent false lumen,the postoperative number of dissection tears in the thoracic aorta and the aortic arch type.Meanwhile,RBS usage,the length of the covered stent in the descending thoracic aorta and the distance from the residual first tear to the LSA could have positive effect on the prognosis. 展开更多
关键词 Type B AORTIC dissection THORACIC ENDOVASCULAR AORTIC repair DISTAL SEGMENT AORTIC enlargement Risk factor
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Methylated CpG dinucleotides in the 5 -a reductase 2 gene may explain finasteride resistance in benign prostatic enlargement patients 被引量:4
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作者 Zhe-Min Lin Dong-Dong Fan +2 位作者 Song Jin Zhan-Liang Liu Yi-Nong Niu 《Asian Journal of Andrology》 SCIE CAS CSCD 2021年第3期266-272,共7页
The inhibition of 5-a reductase type 2(SRD5A2)by finasteride is commonly used for the management of urinary obstruction resulting from benign prostatic enlargement(BPE).Certain BPE patients showing no SRD5A2 protein e... The inhibition of 5-a reductase type 2(SRD5A2)by finasteride is commonly used for the management of urinary obstruction resulting from benign prostatic enlargement(BPE).Certain BPE patients showing no SRD5A2 protein expression are resistant to finasteride therapy.Our previous work showed that methylated cytosine-phosphate-guanine(CpG)islands in the SRD5A2 gene might account for the absence or reduction of SRD5A2 protein expression.Here,we found that the expression of the SRD5A2 protein was variable and that weak expression of the SRD5A2 protein(scored 0-100)occurred in 10.0%(4/40)of benign adult prostates.We showed that the expression of SRD5A2 was negatively correlated with DNA methyltransferase 1(DNMT1)expression.In vitro SRD5A2-negative BPH-1 cells were resistant to finasteride treatment,and SRD5A2 was re-expressed in BPH-1 cells when SRD5A2 was demethylated by 5-Aza-2T-deoxycytidine(5-Aza-CdR)or N-phthalyl-L-tryptophan(RG108).Furthermore,we determined the exact methylation ratios of CpG dinucleotides in a CpG island of SRD5A2 through MassArray quantitative methylation analysis.Ten methylated CpG dinucleotides,including four CpG dinucleotides in the promoter and six CpG dinucleotides in the first exon,were found in a CpG island located from-400 bp to+600 bp in SRD5A2,which might lead to the silencing of SRD5A2 and the absence or reduction of SRD5A2 protein expression.Finasteride cannot exert a therapeutic effect on patients lacking SRD5A2,which may partially account for the resistance to finasteride observed in certain BPE patients. 展开更多
关键词 5-a reductase benign prostatic enlargement CpG island methylated CpG dinucleotides METHYLATION
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Hematoma enlargement-related factors in hypertensive cerebral hemorrhage 被引量:4
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作者 Dengji Pan Zhouping Tang Feng Xu Di Chen Xingyong Chen Xiangwu Meng Suiqiang Zhu Wei Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第8期925-928,共4页
BACKGROUND:Continuous hemorrhage or hematoma enlargement often occurs following cerebral hemorrhage attacks. OBJECTIVE: To retrospectively analyze the influential factors for hematoma enlargement in patients with hy... BACKGROUND:Continuous hemorrhage or hematoma enlargement often occurs following cerebral hemorrhage attacks. OBJECTIVE: To retrospectively analyze the influential factors for hematoma enlargement in patients with hypertensive cerebral hemorrhage prior to minimally invasive surgery. DESIGN, TIME AND SETTING: A comparative analysis of 90 patients with cerebral hemorrhage undergoing minimally invasive surgery at the Department of Neurology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology between April 2005 and February 2007. PARTICIPANTS: Fifty-eight males and thirty-one females aged (52.7 ± 5.23) years (range, 28-73 years). METHODS: Cranial CT was performed twice to objectively identify hematoma enlargement. Patients with hematoma enlargement prior to surgery were selected as the observation group (n = 30), and those with no obvious hematoma changes served as the control group (n = 60). Following cranial CT localization, the two groups underwent minimally invasive hematoma aspiration and drainage, according to Standardized Treatment Guidelines for Micro-invasive Aspiration and Drainage of Intracranial Hematoma. MAIN OUTCOME MEASURES: Hemorrhage site, coagulation function, diabetes history, and clinical symptoms. RESULTS: There were no significant differences in hemorrhage sites between the two groups (χ2 = 2.262, P 〉 0.05). The percent of intemperance patients in the observation group was significantly larger than the control group (χ2 = 6.923, P 〈 0.01). No significant differences in terms of percent of coagulation dysfunction or diabetes were determined between the two groups (χ2 = 0.03, 0.08, P 〉 0.05). The percent of patients with clinical deterioration was significantly higher in the observation group, compared to the control group (χ2 = 25.57, P 〈 0.01). CONCLUSION: Intemperance and preoperative clinical deterioration may increase incidence of hematoma enlargement prior to minimally invasive surgery in patients with hypertensive cerebral hemorrhage. 展开更多
关键词 cerebral hemorrhage hematoma enlargement intemperance
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Image of tumor metastasis and inflammatory lymph node enlargement by contrast-enhanced ultrasonography 被引量:5
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作者 Takaya Aoki Fuminori Moriyasu +3 位作者 Kei Yamamoto Masafumi Shimizu Masahiko Yamada Yasuharu Imai 《World Journal of Radiology》 CAS 2011年第12期298-305,共8页
AIM:To compare the difference between tumorinduced lymph node enlargement and inflammation-induced lymph node enlargement by contrast-enhanced ultrasonography and pathological findings. METHODS:A model of tumor-induce... AIM:To compare the difference between tumorinduced lymph node enlargement and inflammation-induced lymph node enlargement by contrast-enhanced ultrasonography and pathological findings. METHODS:A model of tumor-induced lymph node metastasis was prepared by embedding a VX2 tumor into the hind paws of white rabbits.A model of inflammation-induced enlargement was prepared by injecting a suspension of Escherichia coli into separate hind paws of white rabbits.Then,a solution of SonazoidTM(GE Healthcare,Oslo,Norway)was injected subcutaneously in the proximity of the lesion followed by contrast-enhanced ultrasonography of the enlarged popliteal lymph nodes. RESULTS:In the contrast-enhanced ultrasonography of the tumor-induced metastasis model,the sentinel lymph node was imaged.An area of filling defect was observed in that enlarged lymph node.In the histology examination,the area of filling defect corresponded to the metastatic lesion of the tumor.Contrast-enhanced ultrasonography of the model on inflammation-induced lymph node enlargement,and that of the acute inflam-mation model performed 3-7 d later,revealed dense staining that was comparatively uniform.The pathological findings showed acute lymphadenitis mainly due to infiltration of inflammatory cells.Contrast-enhanced ultrasonography that was performed 28 d post-infection in the acute inflammation model showed speckled staining.Inflammation-induced cell infiltration and fiberization,which are findings of chronic lymphadenitis, were seen in the pathological findings. CONCLUSION:Sentinel lymph node imaging was made possible by subcutaneous injection of SonazoidTM.Contrast-enhanced ultrasonography was suggested to be useful in differentiating tumor-induced enlargement and inflammation-induced enlargement of lymph nodes. 展开更多
关键词 Lymph node enlargement Sentinel lymph node Contrast-enhanced ultrasonography Subcutaneous injection Sonazoid^(TM)
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双侧下颌第二磨牙[牙合]面八个牙尖含畸形中央尖一例
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作者 王付利 戴红梅 《中华老年口腔医学杂志》 2026年第1期50-53,共4页
本研究报道了一例罕见的双侧下颌第二磨牙出现八个牙尖的病例,其左下第二磨牙因龋坏导致牙髓感染。为探讨此类畸形患牙的临床特点和治疗策略,通过口内检查、模型测量、影像学检查、口腔数字化扫描等手段明确其特征,完善根管治疗后,调磨... 本研究报道了一例罕见的双侧下颌第二磨牙出现八个牙尖的病例,其左下第二磨牙因龋坏导致牙髓感染。为探讨此类畸形患牙的临床特点和治疗策略,通过口内检查、模型测量、影像学检查、口腔数字化扫描等手段明确其特征,完善根管治疗后,调磨牙冠颊舌径,以减小牙冠的受力面积,协调咬合关系。半年后复查,患牙充填体及牙体情况良好,未出现牙周并发症,患者咬颊症状消失,取得了良好的治疗效果。本研究为罕见牙体畸形诊疗积累了临床经验,提出牙冠形态调整有利于根管治疗后的多牙尖过大磨牙的留存,提示全科口腔医师重视数字化技术在复杂病例中的应用。 展开更多
关键词 双侧第二磨牙 畸形中央尖 八尖磨牙 过大磨牙
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脑膜中动脉栓塞预防超急性硬脑膜外血肿增大的疗效
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作者 李盛善 李树志 +7 位作者 刘国华 宋常伟 张勇 王斌 柴家伟 任大伟 牟敦勇 徐鑫 《中国临床神经外科杂志》 2026年第2期80-83,共4页
目的探讨脑膜中动脉(MMA)栓塞预防超急性硬脑膜外血肿(HEDH)增大的有效性和安全性。方法回顾性分析2021年3月至2023年3月高密市中医院神经外科MMA栓塞治疗的24例HEDH患者的临床资料(MMA组)。选取2019年3月至2021年3月保守治疗的26例HED... 目的探讨脑膜中动脉(MMA)栓塞预防超急性硬脑膜外血肿(HEDH)增大的有效性和安全性。方法回顾性分析2021年3月至2023年3月高密市中医院神经外科MMA栓塞治疗的24例HEDH患者的临床资料(MMA组)。选取2019年3月至2021年3月保守治疗的26例HEDH为对照组。伤后24 h复查CT显示血肿量大于伤后初次CT显示血肿量的50%即为血肿增大。结果伤后24 h,MMA组复查CT显示血肿体积为11~29 mL,中位数14(11~17)mL;其中3例出现血肿增大,发生率为12.5%,均未行开颅手术治疗。对照组伤后24 h复查头部CT显示血肿体积为10~72 mL,中位数17(14~24)mL,血肿增大11例,发生率为42.3%,其中6例行开颅血肿清除术。MMA组血肿增大发生率明显低于对照组(χ^(2)=5.500,P=0.028)。结论血肿侧MMA栓塞可以有效控制HEDH进展,减少血肿增大的风险,能够有效降低患者开颅手术率。 展开更多
关键词 超急性硬脑膜外血肿 脑膜中动脉栓塞 血肿增大 有效性 安全性
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Optimizing CT for the evaluation of vestibular aqueduct enlargement:Inter-rater reproducibility and predictive value of reformatted CT measurements 被引量:4
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作者 Misun Hwang Ryan Marovich +2 位作者 Samuel S.Shin David Chi Barton F.Branstetter IV 《Journal of Otology》 CSCD 2015年第1期13-17,共5页
Enlarged vestibular aqueduct(EVA), the most frequent identifiable cause of congenital hearing loss, is evaluated with high-definition multidetector CT in the axial plane. Our purpose was to determine which reformatted... Enlarged vestibular aqueduct(EVA), the most frequent identifiable cause of congenital hearing loss, is evaluated with high-definition multidetector CT in the axial plane. Our purpose was to determine which reformatted CT measurements are most reproducible. Seven multiplanar reformatted images were created for each of the 64 temporal bones in patients with EVA. Intraclass correlation coefficients(ICC) were used to assess inter-observer variability, and both linear regression and ROC analyses were used to compare the measurements with severity of hearing loss, as assessed by pure tone audiometry. All seven measurements had excellent inter-observer variability, with average-measure ICC ranging from 0.92 to 0.98. There was no statistically significant correlation between the radiologic degree of aqueduct enlargement and severity of hearing loss using any of the seven measurements; ROC analyses revealed areas under the curves ranging from 0.57 to 0.73. Optimal accuracy was obtained with a threshold of 1.75 mm as measured at the aqueductal aperture in the P€oschl plane, with sensitivity of 0.75 and specificity of0.63. Although the radiologic measurement may not serve as a reliable tool for assessing severity of EVA, P€oschl plane reformatting has proven to be better than conventional axial acquisition plane for identifying patients with clinically significant hearing loss. 展开更多
关键词 Enlarged vestibular aqueduct Hearing loss COMPUTED
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泄洪隧洞竖井补排气噪声处理工程实例分析
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作者 夏军忠 苏秀娟 《云南水力发电》 2026年第3期85-87,共3页
泄洪隧洞主要是分担水库的泄洪任务,由于隧洞泄洪流量大,水头高,竖井在泄洪期间由于井筒内补排气流速快,原设计在各平台遗留的孔口面积偏小,运行过程中噪音太大,影响工作人员上下安全,通过增加平台孔口面积处理措施,能改善运行中的噪音... 泄洪隧洞主要是分担水库的泄洪任务,由于隧洞泄洪流量大,水头高,竖井在泄洪期间由于井筒内补排气流速快,原设计在各平台遗留的孔口面积偏小,运行过程中噪音太大,影响工作人员上下安全,通过增加平台孔口面积处理措施,能改善运行中的噪音问题。 展开更多
关键词 泄洪隧洞 竖井 噪音 扩孔处理 通气面积
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