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Effects of P301L-TAU on post-translational modifications of microtubules in human iPSC-derived cortical neurons and TAU transgenic mice
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作者 Mohamed Aghyad Al Kabbani Christoph Köhler Hans Zempel 《Neural Regeneration Research》 SCIE CAS 2025年第8期2348-2360,共13页
TAU is a microtubule-associated protein that promotes microtubule assembly and stability in the axon.TAU is missorted and aggregated in an array of diseases known as tauopathies.Microtubules are essential for neuronal... TAU is a microtubule-associated protein that promotes microtubule assembly and stability in the axon.TAU is missorted and aggregated in an array of diseases known as tauopathies.Microtubules are essential for neuronal function and regulated via a complex set of post-translational modifications,changes of which affect microtubule stability and dynamics,microtubule interaction with other proteins and cellular structures,and mediate recruitment of microtubule-severing enzymes.As impairment of microtubule dynamics causes neuronal dysfunction,we hypothesize cognitive impairment in human disease to be impacted by impairment of microtubule dynamics.We therefore aimed to study the effects of a disease-causing mutation of TAU(P301L)on the levels and localization of microtubule post-translational modifications indicative of microtubule stability and dynamics,to assess whether P301L-TAU causes stability-changing modifications to microtubules.To investigate TAU localization,phosphorylation,and effects on tubulin post-translational modifications,we expressed wild-type or P301L-TAU in human MAPT-KO induced pluripotent stem cell-derived neurons(i Neurons)and studied TAU in neurons in the hippocampus of mice transgenic for human P301L-TAU(p R5 mice).Human neurons expressing the longest TAU isoform(2N4R)with the P301L mutation showed increased TAU phosphorylation at the AT8,but not the p-Ser-262 epitope,and increased polyglutamylation and acetylation of microtubules compared with endogenous TAU-expressing neurons.P301L-TAU showed pronounced somatodendritic presence,but also successful axonal enrichment and a similar axodendritic distribution comparable to exogenously expressed 2N4R-wildtype-TAU.P301L-TAU-expressing hippocampal neurons in transgenic mice showed prominent missorting and tauopathy-typical AT8-phosphorylation of TAU and increased polyglutamylation,but reduced acetylation,of microtubules compared with non-transgenic littermates.In sum,P301L-TAU results in changes in microtubule PTMs,suggestive of impairment of microtubule stability.This is accompanied by missorting and aggregation of TAU in mice but not in i Neurons.Microtubule PTMs/impairment may be of key importance in tauopathies. 展开更多
关键词 human induced pluripotent stem cell MICROTUBULES P301L pR5 mice TAU TAUOPATHY tubulin code
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不同焊丝激光-MIG复合焊接SUS301L/Q450NQR1异种钢接头的组织及性能
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作者 邱培现 邓鸿剑 +4 位作者 陈北平 张纹源 孙中文 朱宗涛 何绍雄 《电焊机》 2025年第1期101-107,共7页
为了降低成本,采用ER309LSi和CHW-55CNH两种不同焊丝,利用激光-MIG复合焊对Q450NQR1和SUS301L钢板进行对接焊,对比研究了两种焊丝接头的组织与性能。结果表明:两种焊丝接头均无未焊透、未熔合等缺陷,焊缝表面呈明显的鱼鳞纹;ER309LSi焊... 为了降低成本,采用ER309LSi和CHW-55CNH两种不同焊丝,利用激光-MIG复合焊对Q450NQR1和SUS301L钢板进行对接焊,对比研究了两种焊丝接头的组织与性能。结果表明:两种焊丝接头均无未焊透、未熔合等缺陷,焊缝表面呈明显的鱼鳞纹;ER309LSi焊丝接头焊缝中心区主要为树枝状结晶的奥氏体以及少量铁素体组成;CHW-55CNH焊丝接头焊缝中心区主要由先共析铁素体以和珠光体组成;CHW-55CNH焊丝接头焊缝硬度(374 HV)大于ER309LSi焊丝接头(217 HV);ER309LSi焊丝接头平均抗拉强度(632.3 MPa)略大于CHW-55CNH焊丝接头(608.6 MPa);两种焊丝接头的中性盐雾腐蚀试验结果相差不大,电化学分析试验结果表明ER309LSi焊丝接头的耐蚀性优于CHW-55CNH焊丝接头。综上,当构件受力或耐蚀性要求不严格的时候,可以用价格较低的CHW-55CNH焊丝替代ER309LSi焊丝。 展开更多
关键词 激光-MIG复合焊 Q450NQR1钢 SUS301L不锈钢 力学性能 耐蚀性
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大豆新品种长农301的选育及栽培技术 被引量:1
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作者 兰磊 王楠 +3 位作者 张萌 蔡欣培 金传军 刘英群 《种子科技》 2024年第5期45-47,共3页
长农301为长春市农业科学院以长密豆30为母本、合农71为父本配制杂交组合,经系谱法多年选育而成的吉林省中熟品种,该品种丰产性好,稳产性强。介绍了长农301的选育过程和农艺性状,分析了其栽培技术要点,以期大范围推广种植长农301,实现... 长农301为长春市农业科学院以长密豆30为母本、合农71为父本配制杂交组合,经系谱法多年选育而成的吉林省中熟品种,该品种丰产性好,稳产性强。介绍了长农301的选育过程和农艺性状,分析了其栽培技术要点,以期大范围推广种植长农301,实现大豆高产、优产。 展开更多
关键词 大豆 长农301 选育 栽培技术
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B301试验区油井结蜡主控因素及对策
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作者 张继红 李琬姝 +2 位作者 谭欣剑 张刚 朱正俊 《特种油气藏》 CAS CSCD 北大核心 2024年第1期169-174,共6页
B301试验区位于H盆地,该试验区目前油井结蜡现象严重,防蜡效果较差,防蜡措施有效期较短,无法满足油井防蜡的需要,亟需找到影响油井结蜡的主控因素。针对上述问题,通过室内实验对产出液中的蜡质、胶质、沥青质和机械杂质含量进行测定。利... B301试验区位于H盆地,该试验区目前油井结蜡现象严重,防蜡效果较差,防蜡措施有效期较短,无法满足油井防蜡的需要,亟需找到影响油井结蜡的主控因素。针对上述问题,通过室内实验对产出液中的蜡质、胶质、沥青质和机械杂质含量进行测定。利用Olga数值模拟软件对温度、压力、流速进行模拟。研究表明:蜡质、沥青质、机械杂质含量以及温度、流速为影响B301试验区油井井筒结蜡的主控因素,影响程度强弱依次为蜡质、温度、沥青质、机械杂质、流速。研究成果可为B301试验区进一步高效开发提供理论与技术基础,为高含蜡油藏防蜡方法提供参考。 展开更多
关键词 采油采气 油井结蜡 主控因素 B301试验区 H盆地
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退火工艺对δ铁素体在301L不锈钢铸坯中溶解行为的影响
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作者 李俊琛 王东 《热加工工艺》 北大核心 2024年第16期49-52,共4页
利用高温热处理炉,分析了轧制前热处理对301L不锈钢铸坯的溶解行为。结果表明,退火时间和温度对δ铁素体在301L铸坯中的溶解影响显著,溶解初期,δ铁素体的含量从12wt%降至6wt%以下。随着退火时间的延长和温度的升高,301L铸坯固态中δ铁... 利用高温热处理炉,分析了轧制前热处理对301L不锈钢铸坯的溶解行为。结果表明,退火时间和温度对δ铁素体在301L铸坯中的溶解影响显著,溶解初期,δ铁素体的含量从12wt%降至6wt%以下。随着退火时间的延长和温度的升高,301L铸坯固态中δ铁素体含量减少,受Cr、Ni的扩散控制显著,1300℃扩散退火60 min后铁素体球化,晶粒尺寸减小为2~3μm,节点处平衡态δ铁素体的球化行为降低了γ/α界面的附加应力,有利于轧制过程。利用动力学方程验证了后期Cr、Ni元素对组织的影响,当退火温度为1210℃时,溶解参数K_(Ni)^(γ)为0.26,Ni的扩散系数D_(NiNi)^(γ)=4.8×10-10cm2/s。δ铁素体的体积分数与退火时间t1/2成正比。研究结果可为301L铸坯的组织控制提供理论指导。 展开更多
关键词 301L铸坯 退火 Δ铁素体 扩散溶解
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中烟特香301特异SNP指纹图谱构建及应用
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作者 田震 孙晋浩 +11 位作者 武钰存 蒋龙 赵勇 冯慧馨 任民 孙治峰 付秋娟 宗浩 刘文涛 刘贯山 吴新儒 李少鹏 《中国烟草科学》 CSCD 北大核心 2024年第5期8-16,共9页
指纹图谱可以用于品种真实性鉴定,为品种的推广种植和工业利用提供技术保障。本研究采用全基因组重测序技术,对包括烤烟新品种中烟特香301在内的33份烟草种质资源进行了单核苷酸多态性(SNP)变异分析,从中鉴定获得中烟特香301特异SNP位点... 指纹图谱可以用于品种真实性鉴定,为品种的推广种植和工业利用提供技术保障。本研究采用全基因组重测序技术,对包括烤烟新品种中烟特香301在内的33份烟草种质资源进行了单核苷酸多态性(SNP)变异分析,从中鉴定获得中烟特香301特异SNP位点268个。利用包括烤烟、雪茄烟、香料烟、白肋烟、晒烟在内的62份不同类型烟草种质资源进行了筛选,初步获得有效SNP标记21个。以2022—2023年山东产区的中烟特香301及其他5个主栽品种的大田新鲜烟叶和初烤烟叶为材料,利用上述21个SNP标记进行品种真实性检测,结果显示,18个SNP标记在所有烟叶中可全部检测到中烟特香301特异SNP位点。利用这18个SNP标记构建的指纹图谱可以用于中烟特香301品种真实性鉴定。 展开更多
关键词 烤烟 中烟特香301 单核苷酸多态性 指纹图谱 品种真实性鉴定
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采用Cyanex 301从废旧三元锂电浸出液中萃取分离镍和钴
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作者 王占昊 丁威 +3 位作者 包申旭 杨思原 侯晓川 许开华 《中国有色金属学报》 EI CAS CSCD 北大核心 2024年第9期3103-3113,共11页
近年来全球电动汽车销量激增,废旧锂电池的回收愈发迫在眉睫。本文以废旧三元锂电池正极材料的硫酸浸出液为研究对象,采用Cyanex 301选择性分离回收其中的Ni(Ⅱ)和Co(Ⅱ);分别考察了初始pH、萃取相比、萃取时间等因素对各金属萃取率的影... 近年来全球电动汽车销量激增,废旧锂电池的回收愈发迫在眉睫。本文以废旧三元锂电池正极材料的硫酸浸出液为研究对象,采用Cyanex 301选择性分离回收其中的Ni(Ⅱ)和Co(Ⅱ);分别考察了初始pH、萃取相比、萃取时间等因素对各金属萃取率的影响,以及反萃剂HCl浓度、反萃时间、反萃温度等因素对金属反萃率的影响。结果表明:在初始pH=2.0、相比(O/A)为2∶1、Cyanex 301体积分数20%、时间30 min的萃取条件下,经两级逆流萃取,Ni(Ⅱ)、Co(Ⅱ)萃取率分别达97.32%和99.45%。萃取完成后,在最优条件下,通过25℃三级逆流反萃Co(Ⅱ)、80℃两级逆流反萃Ni(Ⅱ),反萃率分别达99.23%和99.08%。最后通过红外光谱和核磁共振氢谱初步证明Cyanex 301萃取Ni(Ⅱ)、Co(Ⅱ)的过程为金属离子与S—H键中的H+发生阳离子交换,且与P=S键形成配位键的过程。 展开更多
关键词 废旧三元锂电池 溶剂萃取 Cyanex 301
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miR-301a的上调通过PTEN/PI3K/AKT信号轴诱导巨噬细胞M1极化促进动脉瘤的进展 被引量:1
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作者 梁国新 郭畅 +2 位作者 唐红悦 刘欣 张明明 《海南医学院学报》 CAS 北大核心 2024年第5期350-358,共9页
目的:研究miR-301a通过PTEN/PI3K/AKT信号轴调节巨噬细胞M1极化加速血管紧张素Ⅱ(AngⅡ)诱导的腹动脉瘤(AAA)进展的机制。方法:体内实验中,8~10周龄ApoE^(-/-)雄性小鼠分为对照组、模型组、miR-301a过表达组,输注生理盐水(saline)为对照... 目的:研究miR-301a通过PTEN/PI3K/AKT信号轴调节巨噬细胞M1极化加速血管紧张素Ⅱ(AngⅡ)诱导的腹动脉瘤(AAA)进展的机制。方法:体内实验中,8~10周龄ApoE^(-/-)雄性小鼠分为对照组、模型组、miR-301a过表达组,输注生理盐水(saline)为对照组(n=15),通过血管紧张素Ⅱ(AngⅡ)诱导建成AAA模型(n=45);THP-1细胞随机分为对照组、AngⅡ+agomir NC组、AngⅡ+miR-301a agomir组和AngⅡ+miR-301a agomir+LY(LY294002)组;使用生物信息学、ELISA、Western blot、qRT-PCR和双荧光素酶实验研究miR-301a调控巨噬细胞极化促动脉瘤进展的机制。结果:与对照组相比,AAA模型组的miR-301a表达上调,主动脉直径增粗,miR-301a的过表达显著增加了动脉直径;TargetScan7.2数据库预测miR-301a与PTEN 3’-UTR之间存在结合位点,双荧光素酶报告基因分析证实PTEN是THP-1巨噬细胞中miR-301a的直接靶标;GO和KEGG通路富集分析显示PI3K/AKT/和NF-κB信号的通路可能是巨噬细胞向M1极化的关键通路;体内、体外实验证明miR-301a通过PI3K/AKT/NF-κB信号通路调控巨噬细胞向M1表型极化,上调基质金属蛋白酶和炎症因子的表达,促进动脉瘤进展。此外,miR-301a联合MMP-9可作为预测动脉瘤破裂的非侵入性生物标志物。结论:miR-301a通过PTEN/PI3K/AKT途径促进巨噬细胞的M1极化,从而加速动脉瘤的进展,在AAA的疾病进展中发挥了关键作用。 展开更多
关键词 腹主动脉瘤 miR-301a 核转录因子ΚB 巨噬细胞极化 基质金属蛋白酶9
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Is China’s Foreign Investment Policy to Blame for US-China “Forced Technology Transfer” and Trade Conf lict?——Comment on Trump Administration’s Section 301 Investigation of China
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作者 Li Liming Liu Haibo Zhang Yafeng 《China Economist》 2020年第2期42-63,共22页
The paper presents a new analytical framework to discuss the effect of Chinese foreign investment policy on the international technology transfer absorbed by enterprises of different ownership.The US Trade Representat... The paper presents a new analytical framework to discuss the effect of Chinese foreign investment policy on the international technology transfer absorbed by enterprises of different ownership.The US Trade Representative claims that the Chinese government’s requirements regarding joint ventures pressure US companies to transfer intellectual property to Chinese companies.However,we argue that:(1)Based on analysis of the technical fees of technology import contracts and the number of US patents transferred to enterprises registered in the Chinese mainland,China’s foreign investment policy does not pressure US companies to transfer unremunerated technology to Chinese companies.(2)The invention and utility model patents filed by Chinese joint-venture enterprises or Chinese partner companies do not show an abnormally rapid growth,which means China’s FDI policy does not force US companies to transfer intellectual property in exchange for China’s market.(3)After 2012,the US-China technology transfer absorbed by enterprises of different ownership showed a significantly positive effect in reducing China-US trade surplus. 展开更多
关键词 technology transfer intellectual property trade balance FDI policy section 301 survey
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美国对华301措施的美国国内法审视和中国应对启示——以HMTX公司诉美国案为例
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作者 刘瑛 杨辰 《国际贸易》 CSSCI 北大核心 2024年第4期87-96,共10页
美国对华301额外关税在美国国内引起了一系列诉讼,美国国际贸易法院(CIT)将HMTX公司诉美国案指定为样本案件。CIT的该案判决没有支持政治问题排除原则的适用,肯定了CIT对301关税事项的管辖权,进而认定中国的报复行为构成了与特定的不公... 美国对华301额外关税在美国国内引起了一系列诉讼,美国国际贸易法院(CIT)将HMTX公司诉美国案指定为样本案件。CIT的该案判决没有支持政治问题排除原则的适用,肯定了CIT对301关税事项的管辖权,进而认定中国的报复行为构成了与特定的不公平贸易政策“相关”的行为,美国贸易代表办公室(USTR)没有越权。CIT认为USTR未完整履行充分论述征税理由的义务,责成USTR对充分回应利害关系方提交的评论意见做出进一步解释。CIT最终认定USTR的重审决定符合美国法,但标准过于宽松。从本案观察,中国企业需充分利用公众评论程序、求诸关税排除程序,以及协助美国企业诉诸美国国内司法程序,从而尽可能减少额外关税的影响。 展开更多
关键词 301 措施 HMTX 公司诉美国案 关税排除
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针刺调控脑缺血再灌注损伤大鼠海马组织miR-301a-5p的表达
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作者 刘晓月 江姗姗 +4 位作者 王瑶 谢灿明 向静 陈楚淘 田浩梅 《神经解剖学杂志》 CAS CSCD 北大核心 2024年第5期613-618,共6页
目的:通过制备大鼠脑缺血再灌注损伤(CIRI)模型探讨针刺对大鼠缺血侧海马组织miR-301a-5p表达的影响。方法:线栓法制备大脑中动脉闭塞/再灌注(MCAO/R)大鼠模型,利用针刺进行干预。采用改良Garcia评分法检测大鼠神经功能,TTC染色法检测... 目的:通过制备大鼠脑缺血再灌注损伤(CIRI)模型探讨针刺对大鼠缺血侧海马组织miR-301a-5p表达的影响。方法:线栓法制备大脑中动脉闭塞/再灌注(MCAO/R)大鼠模型,利用针刺进行干预。采用改良Garcia评分法检测大鼠神经功能,TTC染色法检测脑梗死体积比,RT-qPCR检测缺血侧海马区miR-301a-5p的表达,并利用在线网站数据库TargetScan8.0、mi-RDB及miRWalk预测miR-301a-5p的靶基因,DAVID数据库对靶基因进行基因本体(GO)分析,HE染色观察细胞病理改变。结果:与MCAO/R组相比,MCAO/R+AC干预组大鼠Garcia评分升高(P<0.05),脑梗死体积减小(P<0.01),缺血侧海马区miR-301a-5p表达量显著增加(P<0.01)。预测miR-301a-5p有交集的靶基因101个,GO分析在生物进程(BP)中发现miR-301a-5p靶基因富集于白细胞介素-6(IL-6)的调控及糖皮质激素反应等相关炎症因子,且在MCAO/R组观察到细胞坏死,炎性细胞浸润,MCAO/R+AC组可见散在的炎性细胞浸润。结论:针刺可降低CIRI大鼠神经功能缺损症状,减少脑梗死体积,其机制可能与激活miR-301a-5p的表达抑制细胞炎症有关。 展开更多
关键词 针刺 脑缺血再灌注损伤 miR-301a-5p 炎症 大鼠
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Effect of intraoperative injection of esketamine on postoperative analgesia and postoperative rehabilitation after cesarean section 被引量:2
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作者 Hong-Zhuan Chen Yi Gao +4 位作者 Ke-Ke Li Li An Jing Yan Hong Li Jin Zhang 《World Journal of Clinical Cases》 SCIE 2024年第28期6195-6203,共9页
BACKGROUND Following cesarean section,a significant number of women encounter moderate to severe pain.Inadequate management of acute pain post-cesarean section can have far-reaching implications,adversely impacting ma... BACKGROUND Following cesarean section,a significant number of women encounter moderate to severe pain.Inadequate management of acute pain post-cesarean section can have far-reaching implications,adversely impacting maternal emotional wellbeing,daily activities,breastfeeding,and neonatal care.It may also impede maternal organ function recovery,leading to escalated opioid usage,heightened risk of postpartum depression,and the development of chronic postoperative pain.Both the Chinese Enhanced Recovery After Surgery(ERAS)guidelines and the American ERAS Society guidelines consistently advocate for the adoption of multimodal analgesia protocols in post-cesarean section pain management.Esketamine,functioning as an antagonist of the N-Methyl-D-Aspartate receptor,has been validated for pain management in surgical patients and has exhibited effectiveness in depression treatment.Research has suggested that incorporating esketamine into postoperative pain management via pain pumps can lead to improvements in short-term depression and pain outcomes.This study aims to assess the efficacy and safety of administering a single dose of esketamine during cesarean section.AIM To investigate the effect of intraoperative injection of esketamine on postoperative analgesia and postoperative rehabilitation after cesarean section.METHODS A total of 315 women undergoing elective cesarean section under combined spinal-epidural anesthesia were randomized into three groups:low-dose esketamine(0.15 mg/kg),high-dose esketamine(0.25 mg/kg),and control(saline).Postoperative Visual Analog Scale(VAS)scores were recorded at 6 hours,12 hours,24 hours,and 48 hours.Edinburgh Postnatal Depression Scale(EPDS)scores were noted on 2 days,7 days and 42 days.Ramsay sedation scores were assessed at specified intervals post-injection.Postoperative adverse reactions were also recorded.RESULTS Low-dose group and high-dose group compared to control group,had significantly lower postoperative VAS pain scores at 6 hours 12 hours,and 24 hours(P<0.05),with reduced analgesic usage(P<0.05).EPDS scores and postpartum depression rates were significantly lower on 2 days and 7 days(P<0.05).No significant differences in first exhaust and defecation times were observed(P>0.05),but ambulation times were shorter(P<0.05).Ramsay scores were higher at 5 minutes,15 minutes,and upon room exit(P<0.05).Low-dose group and high-dose group had higher incidences of hallucination,lethargy,and diplopia within 2 hours(P<0.05),and with low-dose group had lower incidences of hallucination,lethargy,and diplopia than high-dose group(P<0.05).CONCLUSION Esketamine enhances analgesia and postpartum recovery;a 0.15 mg/kg dose is optimal for cesarean sections,balancing efficacy with minimized adverse effects. 展开更多
关键词 MATERNITY Cesarean section DEPRESSION Esketamine Postoperative analgesia
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Clinical nursing value of predictive nursing in reducing complications of pregnant women undergoing short-term massive blood transfusion during cesarean section 被引量:1
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作者 Li Cheng Li-Ping Li +2 位作者 Yuan-Yuan Zhang Fang Deng Ting-Ting Lan 《World Journal of Clinical Cases》 SCIE 2024年第1期51-58,共8页
BACKGROUND Cesarean hemorrhage is one of the serious complications,and short-term massive blood transfusion can easily cause postoperative infection and physical stress response.However,predictive nursing intervention... BACKGROUND Cesarean hemorrhage is one of the serious complications,and short-term massive blood transfusion can easily cause postoperative infection and physical stress response.However,predictive nursing intervention has important clinical significance for it.AIM To explore the effect of predictive nursing intervention on the stress response and complications of women undergoing short-term mass blood transfusion during cesarean section(CS).METHODS A clinical medical record of 100 pregnant women undergoing rapid mass blood transfusion during sections from June 2019 to June 2021.According to the different nursing methods,patients divided into control group(n=50)and observation group(n=50).Among them,the control group implemented routine nursing,and the observation group implemented predictive nursing intervention based on the control group.Moreover,compared the differences in stress res-ponse,complications,and pain scores before and after the nursing of pregnant women undergoing rapid mass blood transfusion during CS.RESULTS The anxiety and depression scores of pregnant women in the two groups were significantly improved after nursing,and the psychological stress response of the observation group was significantly lower than that of the control group(P<0.05).The heart rate and mean arterial pressure(MAP)of the observation group during delivery were lower than those of the control group,and the MAP at the end of delivery was lower than that of the control group(P<0.05).Moreover,different pain scores improved significantly in both groups,with the observation group considerably less than the control group(P<0.05).After nursing,complications such as skin rash,urinary retention,chills,diarrhea,and anaphylactic shock in the observation group were 18%,which significantly higher than in the control group(4%)(P<0.05).CONCLUSION Predictive nursing intervention can effectively relieve the pain,reduce the incidence of complications,improve mood and stress response,and serve as a reference value for the nursing of women undergoing rapid mass transfusion during CS. 展开更多
关键词 Predictive care Rapid mass blood transfusion Cesarean section Stress response COMPLICATIONS
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Proper interpretation of sectional analysis results 被引量:1
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作者 Juyuan Zheng Yuli Huang Zhe Qu 《Earthquake Research Advances》 CSCD 2024年第2期65-71,共7页
Displacement control algorithms commonly used to evaluate axial force-bending moment(PM)diagrams may lead to incorrect interpretations of the strength envelopes for asymmetric sections.This paper aims to offer valuabl... Displacement control algorithms commonly used to evaluate axial force-bending moment(PM)diagrams may lead to incorrect interpretations of the strength envelopes for asymmetric sections.This paper aims to offer valuable insights by comparing existing displacement control algorithms with a newly proposed force control algorithm.The main focus is on the PM diagrams of three example sections that exhibit varying degrees of asymmetry.The comparative study indicates that conventional displacement control algorithms inevitably introduce non-zero out-of-plane bending moments.The reported PM diagram in such cases erroneously neglects the out-of-plane moment and fails to represent the strength envelope accurately.This oversight results in significant and unconservative errors when verifying the strength of asymmetric sections. 展开更多
关键词 Fiber section model Axial force-moment interaction diagram Limit state Failure surface
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Cross section determination of^(27)Al(n,2n)^(26)Al reaction induced by 14-MeV neutrons uniting with D-T neutron activation and AMS techniques 被引量:1
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作者 Xian-Lin Yang Chang-Lin Lan +6 位作者 Yu-Ting Wei Yi Zhang Gong Jiang Bo Xie Yu Liu Hong-Tao Shen Xiao-Jun Sun 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期78-89,共12页
Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great significance.To address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al re... Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great significance.To address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al reaction cross section,the activation method and accelerator mass spectrometry(AMS)technique were used to determine the^(27)Al(n,2n)^(26)Al cross section,which could be used as a D-T plasma ion temperature monitor in fusion reactors.At the China Academy of Engineering Physics,neutron activation was performed using a K-400 neutron generator produced by the T(d,n)4He reaction.The^(26)Al∕^(27)Al isotope ratios were measured using the newly installed GYIG 1 MV AMS at the Institute of Geochemistry,Chinese Academy of Sciences.The neutron flux was monitored by measuring the activity of 92mNb produced by the 93Nb(n,2n)92mNb reaction.The measured results were compared with available data in the experimental nuclear reaction database,and the measured values showed a reasonable degree of consistency with partially available literature data.The newly acquired cross-sectional data at 12 neutron energy points through systematic measurements clarified the divergence,which has two different growth trends from the existing experimental values.The obtained results are also compared with the corresponding evaluated database,and the newly calculated excitation functions with TALYS−1.95 and EMPIRE−3.2 codes,the agreement with CENDL−3.2,TENDL-2021 and EMPIRE−3.2 results are generally acceptable.A substantial improvement in the knowledge of the^(27)Al(n,2n)^(26)Al reaction excitation function was obtained in the present work,which will lay the foundation for the diagnosis of the fusion ion temperature,testing of the nuclear physics model,evaluation of nuclear data,etc. 展开更多
关键词 14-MeV neutron ^(27)Al(n 2n)^(26)Al Cross section AMS
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Associations of Perchlorate,Nitrate,and Thiocyanate with Sex Hormones among Children:A Nationally Representative Cross-sectional Study in U.S.
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作者 Yiwen Wang Guodong Ding +1 位作者 Peipei Hu Yongjun Zhang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第6期666-671,共6页
Nitrates,thiocyanates,and perchlorates are ubiquitous in the environment and can be introduced to the public through various dietary and environmental sources.Nitrates,thiocyanates,and perchlorates mainly affect healt... Nitrates,thiocyanates,and perchlorates are ubiquitous in the environment and can be introduced to the public through various dietary and environmental sources.Nitrates,thiocyanates,and perchlorates mainly affect health via the same mechanism.These toxins may act as endocrine disrupters and can result in decreased levels of thyroid hormones^([1]). 展开更多
关键词 mechanism sectional PERCHLORATE
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Theoretical study of differential cross sections for the ionization of helium by fast proton impact
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作者 M Mondal B Mandal +2 位作者 T Mistry D Jana M Purkait 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期255-264,共10页
We present the angular distribution of the ejected electron for single ionization of He by fast proton impact.A fourbody formalism of the three-Coulomb wave is applied to calculate the triple differential cross sectio... We present the angular distribution of the ejected electron for single ionization of He by fast proton impact.A fourbody formalism of the three-Coulomb wave is applied to calculate the triple differential cross sections at several impact energies in the scattering,perpendicular and azimuthal planes.Moreover,the three-body formalism of three-Coulomb,two-Coulomb and first Born approximation models has also been used to study the many-body effect on electron emission and the validity of the models.In the three-Coulomb wave model,the final state wave function incorporates distortion due to the three-body mutual Coulombic interaction.In this formalism,we use an uncorrelated and correlated Born initial state,which consists of a plane wave for the incoming projectile times a two-electron bound state wavefunction of the helium atom representing the 1s^(2)(1S)state.But,in the case of the three-body formalism,the initial state wavefunction consists of a long-range Coulomb distortion for the incoming projectile and one active electron of the He atom described by the Roothaan–Hartree–Fock wavefunction.The structure with a single or two peaks with unequal intensity is observed in the angular distributions of the triple differential cross sections for the different kinematic conditions.In addition,the influence of static electron correlations is investigated using different bound state wavefunctions for the ground state of the He target.In the four-body formalism,the present computations are very fast by reducing a nine-dimensional integral to a two-dimensional real integral.Despite the simplicity and speed of the proposed quadrature,the comparison shows that the obtained results are in reasonable agreement with the experiment and are compatible with those of other theories. 展开更多
关键词 IONIZATION cross sections COLLISION ATOMS ions
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Adjuvant Rectal Diclofenac for Post Operative Analgesia after Caesarean Section—A Randomized Controlled Study
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作者 Eziaha Eric S. Ede Ayodele A. Olaleye +4 位作者 John C. Irechukwu Uchenna Nelson Nwaedu Borniface N. Ejikeme Vincent Chidiebere Ali Bartholomew I. Olinya 《Open Journal of Obstetrics and Gynecology》 2024年第4期591-609,共19页
BACKGROUND: Pain management following caesarean section still remains a challenge in our environment. Most potent analgesics are either not readily available or expensive. Diclofenac suppository is an NSAID that can b... BACKGROUND: Pain management following caesarean section still remains a challenge in our environment. Most potent analgesics are either not readily available or expensive. Diclofenac suppository is an NSAID that can be used for postoperative analgesia. It is available and affordable. OBJECTIVE: To compare the efficacy and safety of combined rectal diclofenac and intramuscular pentazocine with intramuscular pentazocine alone for post operative pain control following lower segment caesarean section. METHODOLOGY: A total of 120 women who met the selection criteria scheduled for caesarean section under spinal anaesthesia with bupivacaine were randomized into two equal groups to receive either 75 mg diclofenac suppository 12 hourly for 24 hours or one anusol suppository (the placebo) 12 hourly for 24 hours. Both groups received pentazocine as primary analgesia. RESULT: The primary outcome measure is the proportion of patients with severe pain at 24 hours using the visual analogue rating scale. Secondary outcome measures are the time from surgery to ambulation, Passage of flatus, maternal satisfaction and presence of complications. Statistical analysis was done using spss version 22 and graph pad statistical package. Student T-test was used for continuous variables whereas chi square was used for categorical variables P CONCLUSION: Adjuvant rectal diclofenac is superior to pentazocine alone in the management of pain after caesarean section. Less number of patients had moderate to severe pain at 24 hours post operation. Maternal satisfaction in relation to pain management is better with diclofenac suppository. The levels of complications were comparable in both groups. 展开更多
关键词 PAIN Caesarean section DICLOFENAC PLACEBO SUPPOSITORY
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Acceptability of Caesarean Section among Pregnant Women Seeking Antenatal Care at Women and Newborn Hospital-University Teaching Hospitals, Lusaka Zambia
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作者 Huhenya Sharon Chongo Maureen Masumo Namayipo Nankamba 《Open Journal of Obstetrics and Gynecology》 2024年第5期721-743,共23页
Caesarean section remains one of the most common obstetric and major operations performed on women during pregnancy and has contributed to improving maternal and foetal health. Consequently, significant mortality and ... Caesarean section remains one of the most common obstetric and major operations performed on women during pregnancy and has contributed to improving maternal and foetal health. Consequently, significant mortality and morbidity from pregnancy and labour-related causes can be eliminated by a timely caesarean section. The acceptance of the life-saving procedure remains unsatisfactory in most sub-Saharan nations. The study aimed to assess the acceptability of caesarean section and associated factors among pregnant women seeking antenatal care at Women and Newborn Hospital-University Teaching Hospitals in Lusaka Zambia. The study utilised a quantitative cross-sectional analytical study design involving 420 pregnant women selected using systematic random sampling at Women and Newborn Hospital-University Teaching Hospitals Lusaka Zambia. Data was obtained using an Interview schedule and analysed using R software version 4.3.2. Chi-square, Fisher’s exact test, Wilcoxon rank sum test and binary logistic regression for statistical analysis at a 5% level of significance. The study found that the acceptability of Caesarean section as a mode of delivery was low (29%) among respondents at Women and Newborn Hospital-University Teaching Hospitals. This was influenced by marital status (P = 0.002), socioeconomic status (P = 0.050), parity (P = 0.004), gestation age (P = 0.008), previous history of caesarean section (P = 0.003), knowledge (P < 0.001), attitude (P < 0.001), and sociocultural beliefs (P = 0.045). Low acceptability of Caesarean section delivery is common among women at Women and Newborn Hospital-University Teaching Hospitals, despite its potential benefits for maternal and neonatal health. Socio-demographic and maternal characteristics, knowledge, attitude, perception, and socio-cultural beliefs play a major role in determining acceptability. Therefore, efforts to enhance acceptability should focus on improving knowledge, enhancing positive perceptions and attitudes, and allaying negative socio-cultural beliefs towards caesarean section. 展开更多
关键词 Caesareans section ACCEPTABILITY Knowledge ATTITUDE PERCEPTION
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Utero-Cutaneous Fistula after Caesarean Section Delivery: Diagnosis and Management of a Rare Complication
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作者 Aalaa A. Wahab Marzooq Maryam Mohamed Mahmood +1 位作者 Hiba Moayad Saeed Rabab Mustafa Mohamed Khalafalla 《Open Journal of Obstetrics and Gynecology》 2024年第8期1124-1129,共6页
Utero-cutaneous fistula following cesarean section is a rare occurrence. We present the case of a 34-year-old woman who presented to our department four years after her second cesarean section with a history of pain a... Utero-cutaneous fistula following cesarean section is a rare occurrence. We present the case of a 34-year-old woman who presented to our department four years after her second cesarean section with a history of pain and blood discharge from a previous Pfannenstiel incision, during menstruation, with an absence of vaginal menstrual flow. Despite a prior surgical repair operation, her symptoms persisted. A pelvic MRI was done to confirm the diagnosis of utero-cutaneous fistula, and surgical management was pursued. This case report aims to contribute to the existing literature on utero-cutaneous fistula and provide insights into the diagnostic considerations and management strategies for this rare complication. 展开更多
关键词 Cesarean section Uterocutaneous Fistula COMPLICATION UTERUS
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