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宁夏幼儿园教师性教育态度与实施现状调查研究
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作者 马芳 滑戌 《宁夏师范学院学报》 2024年第5期52-61,共10页
幼儿教师具备良好的性教育态度和实施能力是3~6岁幼儿性健康发展的重要保障。为了解幼儿教师在幼儿园开展性教育的态度和实施现状并探明二者的影响因素,本研究对宁夏地区823名幼儿教师进行问卷调查,通过二元logistic回归分析发现,教师... 幼儿教师具备良好的性教育态度和实施能力是3~6岁幼儿性健康发展的重要保障。为了解幼儿教师在幼儿园开展性教育的态度和实施现状并探明二者的影响因素,本研究对宁夏地区823名幼儿教师进行问卷调查,通过二元logistic回归分析发现,教师在幼儿园开展性教育过程中,家园合作意识薄弱、缺乏对幼儿性教育的全面认识;教师的不同专业、教龄、年龄、编制状况、获得性教育知识的途径数均对教师在幼儿园开展性教育的态度和实施存在影响。通过线性回归分析进一步发现,教师在幼儿园开展性教育的态度越积极、获取性教育知识的途径数越多,对幼儿性行为的处理水平越高。鉴于此,为促进教师在幼儿园更好地开展性教育工作,应加快建立幼儿性教育课程体系,提高幼儿教师专业师资的性教育专业素养,加强家园合作的意识。 展开更多
关键词 幼儿教师 幼儿性教育 教育态度 西北地区
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基于NF-κB信号通路的玉屏风散加味含药血清对RLE-6TN细胞炎症反应的影响 被引量:1
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作者 孟佳磊 马宇慧 +3 位作者 袁林 叶慧 华旭 雷鸣 《中国中医药信息杂志》 CAS CSCD 2024年第1期84-90,共7页
目的观察玉屏风散加味含药血清对大鼠肺上皮Ⅱ型细胞RLE-6TN炎症反应的影响,基于核因子(NF)-κB信号通路探讨其作用机制。方法采用脂多糖诱导RLE-6TN细胞炎症反应,将细胞分为对照组、模型组、地塞米松血清组和5%、10%、20%中药血清组,... 目的观察玉屏风散加味含药血清对大鼠肺上皮Ⅱ型细胞RLE-6TN炎症反应的影响,基于核因子(NF)-κB信号通路探讨其作用机制。方法采用脂多糖诱导RLE-6TN细胞炎症反应,将细胞分为对照组、模型组、地塞米松血清组和5%、10%、20%中药血清组,分别以不同血清干预细胞24 h。试剂盒检测细胞上清液乳酸脱氢酶(LDH)含量,荧光染色检测细胞活性氧(ROS)含量,Hoechst/PI双染观察细胞凋亡情况,ELISA检测细胞上清液肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6、IL-1β含量,RT-qPCR检测细胞Toll样受体4(TLR4)、髓样分化因子88(MyD88)、NF-κB抑制蛋白α(IκBα)mRNA表达,Western blot检测细胞TLR4、MyD88、NF-κBp65、IκBα蛋白表达。结果与对照组比较,模型组RLE-6TN细胞上清液LDH、TNF-α、IL-6、IL-1β及细胞ROS含量显著升高(P<0.01),细胞凋亡率显著升高(P<0.01),TLR4、MyD88 mRNA和蛋白表达显著升高(P<0.01),IκBαmRNA表达显著降低(P<0.01),p-NF-κBp65/NF-κBp65、p-IκBα/IκBα比值显著升高(P<0.01);与模型组比较,20%中药血清组和地塞米松血清组细胞RLE-6TN细胞上清液LDH、TNF-α、IL-6、IL-1β及细胞ROS含量显著降低(P<0.01),细胞凋亡率显著降低(P<0.01),TLR4、MyD88 mRNA和蛋白表达显著降低(P<0.05,P<0.01),IκBαmRNA表达显著升高(P<0.01),p-NF-κBp65/NF-κBp65、p-IκBα/IκBα比值显著降低(P<0.05,P<0.01)。结论玉屏风散加味含药血清可减轻RLE-6TN细胞炎症反应,其机制可能与调控NF-κB信号通路有关。 展开更多
关键词 玉屏风散加味 脓毒症急性肺损伤 含药血清 NF-ΚB信号通路 RLE-6TN细胞
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Inhibiting the phase transition of WO_(3)for highly stable aqueous electrochromic battery
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作者 Zhisheng Wu Zhendong Lian +10 位作者 Ting Ding Jielei Li Jincheng xu Jinxiao Wang Liangxing Zhang Bo Wang Shi Chen Peng Xiao hua xu Shuang-Peng Wang Kar Wei Ng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期86-95,I0003,共11页
Aqueous electrochromic battery(ECB)has shown intense potential for achieving energy storage and saving simultaneously.While tungsten oxide(WO_(3))is the most promising EC material for commercialization,the cycling sta... Aqueous electrochromic battery(ECB)has shown intense potential for achieving energy storage and saving simultaneously.While tungsten oxide(WO_(3))is the most promising EC material for commercialization,the cycling stability of WO_(3)-based aqueous ECBs is currently unsatisfactory due to the repeated phase transition during the redox process and the corrosion by acidic electrolytes.Herein,we present a titanium-tungsten oxide alloy(Ti-WO_(3))with controllable morphology and crystal phase synthesized by a facile hot injection method to overcome the challenges.In contrast to conventional monoclinic WO_(3),the Ti-WO_(3)nanorods can stably maintain their cubic crystal phase during the redox reaction in an acidic electrolyte,thus leading to dramatically enhanced response speed and cycling stability,Specifically,when working in a well-matched hybrid Al^(3+)/Zn^(2+)aqueous electrolyte,our phasetransition-free cubic Ti-WO_(3)exhibits an ultra-high cycling stability(>20000 cycles),fast response speed(3,95 s/4,65 s for bleaching/coloring),as well as excellent discharge areal capacity of 214.5 mA h m^(-2),We further fabricate a fully complementa ry aqueous electrochromic device,for the first time,using a Ti-WO_(3)/Prussian blue device architecture.Remarkably,the complementary ECB shows>10000 stable operation cycles,attesting to the feasibility of our Ti-WO_(3)for practical applications.Our work validates the significance of inhibiting the phase transitions of WO_(3)during the electrochromic process for realizing highly cyclable aqueous ECB,which can possibly provide a generalized design guidance for other high-quality metallic oxides for electrochemical applications. 展开更多
关键词 Aqueous electrochromic battery Ti-WO_(3) Phase transition Long-term stability
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Analysis of Factors Related to Vasovagal Response in Apheresis Blood Donors and the Establishment of Prediction Model Based on BP Neural Network Algorithm
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作者 Xin Hu hua xu Fengqin Li 《Journal of Clinical and Nursing Research》 2024年第6期276-283,共8页
Objective:To analyze the factors related to vessel vasovagal reaction(VVR)in apheresis donors,establish a mathematical model for predicting the correlation factors and occurrence risk,and use the prediction model to i... Objective:To analyze the factors related to vessel vasovagal reaction(VVR)in apheresis donors,establish a mathematical model for predicting the correlation factors and occurrence risk,and use the prediction model to intervene in high-risk VVR blood donors,improve the blood donation experience,and retain blood donors.Methods:A total of 316 blood donors from the Xi'an Central Blood Bank from June to September 2022 were selected to statistically analyze VVR-related factors.A BP neural network prediction model is established with relevant factors as input and DRVR risk as output.Results:First-time blood donors had a high risk of VVR,female risk was high,and sex difference was significant(P value<0.05).The blood pressure before donation and intergroup differences were also significant(P value<0.05).After training,the established BP neural network model has a minimum RMS error of o.116,a correlation coefficient R=0.75,and a test model accuracy of 66.7%.Conclusion:First-time blood donors,women,and relatively low blood pressure are all high-risk groups for VVR.The BP neural network prediction model established in this paper has certain prediction accuracy and can be used as a means to evaluate the risk degree of clinical blood donors. 展开更多
关键词 Vasovagal response Related factors Prediction BP neural network
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Macrophage migration inhibitory factor facilitates astrocytic production of the CCL2 chemokine following spinal cord injury 被引量:1
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作者 Han Zhang Yu-Ming Hu +6 位作者 Ying-Jie Wang Yue Zhou Zhen-Jie Zhu Min-Hao Chen Yong-Jun Wang hua xu You-hua Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第8期1802-1808,共7页
Spinal cord injury causes accumulation of a large number of leukocytes at the lesion site where they contribute to excessive inflammation.Overproduced chemokines are responsible for the migratory process of the leukoc... Spinal cord injury causes accumulation of a large number of leukocytes at the lesion site where they contribute to excessive inflammation.Overproduced chemokines are responsible for the migratory process of the leukocytes,but the regulatory mechanism underlying the production of chemokines from resident cells of the spinal cord has not been fully elucidated.We examined the protein levels of macrophage migration inhibitory factor and chemokine C-C motif chemokine ligand 2 in a spinal cord contusion model at different time points following spinal cord injury.The elevation of macrophage migration inhibitory factor at the lesion site coincided with the increase of chemokine C-C motif chemokine ligand 2 abundance in astrocytes.Stimulation of primary cultured astrocytes with different concentrations of macrophage migration inhibitory factor recombinant protein induced chemokine C-C motif chemokine ligand 2 production from the cells,and the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine attenuated the stimulatory effect.Further investigation into the underlying mechanism on macrophage migration inhibitory factor-mediated astrocytic production of chemokine C-C motif chemokine ligand 2 revealed that macrophage migration inhibitory factor activated intracellular JNK signaling through binding with CD74 receptor.Administration of the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine following spinal cord injury resulted in the reduction of chemokine C-C motif chemokine ligand 2-recruited microglia/macrophages at the lesion site and remarkably improved the hindlimb locomotor function of rats.Our results have provided insights into the functions of astrocyte-activated chemokines in the recruitment of leukocytes and may be beneficial to develop interventions targeting chemokine C-C motif chemokine ligand 2 for neuroinflammation after spinal cord injury. 展开更多
关键词 ASTROCYTES CD74 CHEMOKINE chemokine C-C motif chemokine ligand 2(CCL2) cytokine inflammation LEUKOCYTE MAPKS migration inhibitory factor spinal cord injury
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Assessment of heavy metal pollution in Laizhou Bay(China)using the ecological risk index and the integrated biomarker response of the goby Acanthogobius ommaturus 被引量:1
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作者 Maosheng LIU hua xu +7 位作者 Qiang ZOU Fei FANG Shan SUN Yuting ZHAO Xin HE Yonghui BO Lei YAO Yan FANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1519-1536,共18页
We used the Integrated Biological Responses version 2(IBRv2)method to evaluate the biological eff ects of heavy metals in the sediments in Laizhou Bay,China on the benthic goby Acanthogobius ommaturus.In December 2018... We used the Integrated Biological Responses version 2(IBRv2)method to evaluate the biological eff ects of heavy metals in the sediments in Laizhou Bay,China on the benthic goby Acanthogobius ommaturus.In December 2018,gobies and sediments were collected from 15 stations.We measured the activities of defense enzymes and the contents of malondialdehyde(MDA)and metallothionein(MT)in the goby liver as well as the levels of heavy metals in the sediments and goby muscle tissue.Most of the heavy metal concentrations in sediment at each station were below the Class I criteria set by Chinese Standards for Marine Sediment Quality,and the Håkanson ecological risk index suggested low risk for the heavy metals.We found that A.ommaturus could eff ectively accumulate mercury,cadmium,arsenic,and zinc and that the contents of MT and MDA and the activities of glutathione peroxidase and glutathione reductase were suitable biomarkers of heavy metal pollution in this species.The IBRv2 method integrated these four biomarkers and discriminated stations according to heavy metal pollution.Higher IBRv2 values suggested more adverse eff ects in gobies,corroborating more serious heavy metal contamination.The stations with high IBRv2 values and high contents of heavy metals were mainly distributed in the west and northeast parts of the bay.These results show that the IBRv2 approach is a feasible strategy for assessing heavy metal pollution through biological response and biological status and that it can be implemented for environmental monitoring in Laizhou Bay. 展开更多
关键词 integrated biomarker responses heavy metal ASSESSMENT goby Acanthogobius ommaturus Laizhou Bay
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CHRM3 is a novel prognostic factor of poor prognosis andpromotes glioblastoma progression via activation of oncogenicinvasive growth factors
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作者 BIN ZHANG JIANYI ZHAO +7 位作者 YONGZHI WANG hua xu BO GAO GUANGNING ZHANG BIN HAN GUOHONG SONG JUNCHEN ZHANG WEI MENG 《Oncology Research》 SCIE 2023年第6期917-927,共11页
Glioblastoma(GBM)is the most aggressive cancer of the brain and has a high mortality rate due to the lack of effective treatment strategy.Clarification of molecular mechanisms of GBM’s characteristic invasive growth ... Glioblastoma(GBM)is the most aggressive cancer of the brain and has a high mortality rate due to the lack of effective treatment strategy.Clarification of molecular mechanisms of GBM’s characteristic invasive growth is urgently needed to improve the poor prognosis.Single-nuclear sequencing of primary and recurrent GBM samples revealed that levels of M3 muscarinic acetylcholine receptor(CHRM3)were significantly higher in the recurrent samples than in the primary samples.Moreover,immunohistochemical staining of an array of GBM samples showed that high levels of CHRM3 correlated with poor prognosis,consistent with The Cancer Genome Atlas database.Knockdown of CHRM3 inhibited GBM cell growth and invasion.An assay of orthotopic GBM animal model in vivo indicated that inhibition of CHRM3 significantly suppressed GBM progression with prolonged survival time.Transcriptome analysis revealed that CHRM3 knockdown significantly reduced an array of classic factors involved in cancer invasive growth,including MMP1/MMP3/MMP10/MMP12 and CXCL1/CXCL5/CXCL8.Taken together,CHRM3 is a novel and vital factor of GBM progression via regulation of multiple oncogenic genes and may serve as a new biomarker for prognosis and therapy of GBM patients. 展开更多
关键词 GLIOBLASTOMA PROGNOSIS CHRM3 MMP CXCL
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Numerical Simulation of Dust Removal in the Cyclone Collector of a Straw Crusher Based on a Discrete Phase Model
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作者 Zhuang Wu Chang Su +1 位作者 hua xu Liu Wang 《Fluid Dynamics & Materials Processing》 EI 2023年第5期1143-1157,共15页
The cyclone dust collector is an important subsystem of straw crushers used in agriculture.In the present study,a new type of dust collector with involute morphology is proposed to obtain better dust removal efficienc... The cyclone dust collector is an important subsystem of straw crushers used in agriculture.In the present study,a new type of dust collector with involute morphology is proposed to obtain better dust removal efficiency with respect to that of classical tangential and spiral dust collectors.A discrete phase model(DPM)method is used in synergy with a turbulence model,and the SIMPLE algorithm to simulate the flow field inside the dust collector and the related particle dynamics.It is shown that the internal flow field features a primary swirl,a secondary swirl and blockage effects.Moreover,for the involute dust collector,the tangential velocity in the initial stage and the pressure in the high-pressure area are larger than those obtained for the classical types.The dust removal efficiency is 37.11%,25.3%,and 16.37%for the involute type dust collector,the tangential type and the spiral type,respectively. 展开更多
关键词 Cyclone dust collector the involute type efficiency of dust removal numerical simulation
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杂质对交联聚乙烯电缆内部电场和空间电荷分布影响 被引量:17
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作者 李亚莎 代亚平 +2 位作者 花旭 刘志鹏 王成江 《电工技术学报》 EI CSCD 北大核心 2018年第18期4365-4371,共7页
杂质会影响交联聚乙烯(XLPE)电缆内部电场及空间电荷分布,在电缆绝缘老化与击穿中起着重要作用,因此研究杂质对电缆中电场及空间电荷分布的影响具有重要的意义。本文采用二阶四面体单元剖分的有限元方法计算各节点的电位分布,然后求各... 杂质会影响交联聚乙烯(XLPE)电缆内部电场及空间电荷分布,在电缆绝缘老化与击穿中起着重要作用,因此研究杂质对电缆中电场及空间电荷分布的影响具有重要的意义。本文采用二阶四面体单元剖分的有限元方法计算各节点的电位分布,然后求各节点电位的负梯度得到各节点上的电场强度,对电位移矢量求散度可得各节点的电荷密度。以一个带有杂质颗粒的交联聚乙烯电缆模型为例进行计算,结果表明:在电场作用下,杂质颗粒会离解造成其周围电荷密度集中;杂质颗粒表面积聚的电荷量随颗粒半径的增大而增大,电荷密度随半径的增大而减小;杂质颗粒越靠近高压侧其表面积聚的电荷量越大;杂质颗粒周围的电荷密度值与相对介电常数关系不大,但与电阻率关系密切。 展开更多
关键词 交联聚乙烯电缆 空间电荷 电场强度 杂质
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外电场下交联聚乙烯电介质材料分子结构变化及其电老化微观机理研究 被引量:7
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作者 李亚莎 花旭 +2 位作者 代亚平 刘志鹏 王成江 《原子与分子物理学报》 CAS 北大核心 2019年第3期413-420,共8页
为了从微观角度分析交联聚乙烯(XLPE)材料的电树枝老化,本文采用分子模拟方法计算并优化得到了XLPE分子结构.沿着聚乙烯链施加不同大小电场强度,分析交联聚乙烯分子的几何结构、偶极矩、极化率、电荷分布、前线轨道能量和红外光谱变化规... 为了从微观角度分析交联聚乙烯(XLPE)材料的电树枝老化,本文采用分子模拟方法计算并优化得到了XLPE分子结构.沿着聚乙烯链施加不同大小电场强度,分析交联聚乙烯分子的几何结构、偶极矩、极化率、电荷分布、前线轨道能量和红外光谱变化规律.计算结果表明,随着外电场的增大,交联聚乙烯分子红外光谱发生较大变化;当外施电场达到0.026a.u.后,红外光谱图中出现虚频,表明分子空间结构不再稳定,易发生断键;另外从前线轨道图的变化可以看出断键现象最先发生在交联聚乙烯链端部;沿着电场方向,原子所带电荷量由交联处向端部转移,当外施电场达到0.029a.u.后,链端部的C-H和C-C键断裂产生H·和CH3·自由基.游离的自由基会形成空间电荷并发生积聚,产生局部较大场强,从而进一步影响交联聚乙烯链的空间结构.而电介质内部微观特性的变化必定会导致交联聚乙烯材料绝缘性能的下降,这些变化对揭示交联聚乙烯电缆电树枝形成的微观规律具有重要研究意义. 展开更多
关键词 交联聚乙烯材料 外电场 空间电荷 自由基 分子模拟
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适用于低温地层的纳米复合水泥浆体系研究 被引量:6
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作者 王胜 谌强 +2 位作者 袁学武 华绪 陈礼仪 《石油钻探技术》 CAS CSCD 北大核心 2021年第6期73-80,共8页
为解决低温地层钻探过程中的井壁坍塌和井漏问题,研制了适用于低温地层的纳米复合水泥浆。采用宏观试验与微观分析相结合的方法,研究了低温下纳米Al_(2)O_(3)对硅酸盐-硫铝酸盐复合水泥浆性能和水化过程的影响;以普通硅酸盐水泥与硫铝... 为解决低温地层钻探过程中的井壁坍塌和井漏问题,研制了适用于低温地层的纳米复合水泥浆。采用宏观试验与微观分析相结合的方法,研究了低温下纳米Al_(2)O_(3)对硅酸盐-硫铝酸盐复合水泥浆性能和水化过程的影响;以普通硅酸盐水泥与硫铝酸盐水泥复合产生的水化协同效应为基础,结合纳米Al_(2)O_(3)、防冻剂EG、减水剂JS-1和早强剂TEOA,配制了纳米复合水泥浆NAC;采用扫描电镜、X射线衍射和水化放热试验相结合的方法,研究了NAC的低温水化过程及水化机理。试验得知,温度为-9℃时,纳米复合水泥浆具有良好的初始流动性,可泵期为57 min,初、终凝时间分别为84和101 min,24 h抗压强度为6.9 MPa。研究结果表明,NAC具有直角稠化效应,低温下性能优越,能够满足钻进低温地层时的护壁堵漏要求。 展开更多
关键词 低温 地层 堵漏 水化 协同效应 纳米复合水泥浆 水化机理
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Prognostic Value of Semi-Quantitative 18F-FDG PET/CT Parameters in Hodgkin’s Lymphoma
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作者 Yong Zhou Congyang Hu +7 位作者 Yue Li Xiting Xia Jun Lei Jingyi Chen hua xu Mei He Hongyun Jian Shuping You 《Proceedings of Anticancer Research》 2023年第6期108-115,共8页
Objective:To assess the prognostic value of maximum standardized uptake value(SUVmax),metabolic tumor volume(MTV),and total lesion glycolysis(TLG)determined by 18F-fluorodeoxyglucose positron emission tomography-compu... Objective:To assess the prognostic value of maximum standardized uptake value(SUVmax),metabolic tumor volume(MTV),and total lesion glycolysis(TLG)determined by 18F-fluorodeoxyglucose positron emission tomography-computed tomography(18F-FDG PET/CT)imaging in Hodgkin’s lymphoma patients.Methods:A total of 148 Hodgkin’s lymphoma patients diagnosed with lymph node biopsy from October 2014 to October 2015 were retrospectively analyzed followed by categorizing into good(125 cases)and poor(23 cases)prognosis groups.The chi-squared test was used to analyze the clinicopathological characteristics of Hodgkin’s lymphoma patients with the semi-quantitative 18F-FDG PET/CT parameters;the Spearman method was used to analyze the correlation between the semi-quantitative parameters and clinicopathological features of Hodgkin’s lymphoma;receiver operating characteristic curve was used to analyze the predictive value of the semi-quantitative parameters for poor prognosis of Hodgkin’s lymphoma patients.Results:Mean SUVmax,MTV,and TLG of the 148 cases of Hodgkin’s lymphoma were 7.26±2.38,12.46±3.14 cm3,and 76.83±18.56 g,respectively.Significant variations in the Ann Arbor stage and clinical classification were observed with different levels of semi-quantitative parameters(P<0.05).The semi-quantitative parameters were not correlated with age and gender(P>0.05)but positively correlated with Ann Arbor stage and clinical classification(P<0.05).These parameters in the poor prognosis group were higher than those in the good prognosis group(P<0.05).The area under the curve(AUC)of SUVmax,MTV,and TLG in predicting the poor prognosis group was 0.881,0.875,and 0.838,with cut-off values of 7.264,12.898 cm3,and 74.580g,as well as specificity of 88.8%,84.0%,and 78.4%,and sensitivity of 87.0%,87.0%,and 78.3%,respectively;the AUC of the combined prediction was 0.986,with a specificity of 97.6%and sensitivity of 86.3%.Conclusion:The semi-quantitative 18F-FDG PET/CT parameters provide valuable insights for Hodgkin’s lymphoma prognosis assessment. 展开更多
关键词 Hodgkin’s lymphoma 18F-fluorodeoxyglucose positron emission tomography-computed tomography Maximum standardized uptake value Metabolic tumor volume Total lesion glycolysis PROGNOSIS
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小分子酸与高分子酸在油中扩散行为的分子动力学模拟 被引量:4
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作者 李亚莎 刘志鹏 +2 位作者 花旭 代亚平 沈星如 《绝缘材料》 CAS 北大核心 2018年第9期70-75,共6页
为深入了解小分子酸和高分子酸在油中的扩散行为,利用分子动力学方法分别对甲酸和环烷酸在不同含水量油中的扩散行为进行了模拟研究。根据均方位移计算了两种酸在不同含水量油中的扩散系数,通过径向分布函数观察了两种酸的不同官能团与... 为深入了解小分子酸和高分子酸在油中的扩散行为,利用分子动力学方法分别对甲酸和环烷酸在不同含水量油中的扩散行为进行了模拟研究。根据均方位移计算了两种酸在不同含水量油中的扩散系数,通过径向分布函数观察了两种酸的不同官能团与水分子形成氢键的情况,并且分析了不同酸油模型的动能变化。结果表明:环烷酸的扩散系数明显小于甲酸,且其下降趋势较甲酸平缓;两种酸中羰基氧原子比羟基氧原子更易与水分子形成氢键;酸油模型中水和酸含量越高,形成的氢键数目越多,所具有的动能越大,分子间相互撞击所释放的能量更强,更容易破坏油分子结构的稳定性。 展开更多
关键词 变压器油 分子动力学 扩散系数 氢键
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煤层气井固井水泥的初步探究 被引量:2
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作者 王胜 徐世桐 +4 位作者 汪靖扉 蒋贵 华绪 郭凯彬 赵蒙 《煤矿安全》 CAS 北大核心 2018年第9期27-30,共4页
在煤层气井固井过程中,由于气井压力低,普通固井水泥浆易漏失并渗入煤储层中,阻塞储层的产气孔隙和通道,降低煤层的产气能力,同时影响固井质量。针对这一问题,需要研究出一种水泥浆体系,平衡地层压力,同时水泥浆需要快速凝固,早期强度... 在煤层气井固井过程中,由于气井压力低,普通固井水泥浆易漏失并渗入煤储层中,阻塞储层的产气孔隙和通道,降低煤层的产气能力,同时影响固井质量。针对这一问题,需要研究出一种水泥浆体系,平衡地层压力,同时水泥浆需要快速凝固,早期强度较快上升,在较短时间内形成封闭稳定的通道,进而降低对煤层气产气的影响,达到高效固井的目的。同时,油井水泥成本较高,难以获取。因此,研究低成本、高效固井水泥具有重要的意义。通过选用玻璃微珠、PC42.5R型号的普通硅酸盐水泥以及R.SAC42.5型号的硫铝酸盐水泥3种较易获取的材料以不同的比例进行复合,加快其凝结时间,通过对可泵期、初凝时间、终凝时间以及24、48、72 h时间的养护的强度进行测试,围绕煤层气井高效固井的水泥性能的实际需要,对改性低密度复合水泥配方进行初步探究。 展开更多
关键词 煤层气井 低成本 高效固井 改性 低密度复合水泥
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Study of brain morphology change in Alzheimer’s disease and amnestic mild cognitive impairment compared with normal controls 被引量:4
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作者 huanqing Yang hua xu +10 位作者 Qingfeng Li Yan Jin Weixiong Jiang Jinghua Wang Yina Wu Wei Li Cece Yang Xia Li Shifu Xiao Feng Shi Tao Wang 《General Psychiatry》 CSCD 2019年第2期75-83,共9页
Background With an aggravated social ageing level, the number of patients with Alzheimer's disease (AD) is gradually increasing, and mild cognitive impairment (MCI) is considered to be an early form of Alzheimer&#... Background With an aggravated social ageing level, the number of patients with Alzheimer's disease (AD) is gradually increasing, and mild cognitive impairment (MCI) is considered to be an early form of Alzheimer's disease. How to distinguish diseases in the early stage for the purposes of early diagnosis and treatment is an important topic. Aims The purpose of our study was to investigate the differences in brain cortical thickness and surface area among elderly patients with AD, elderly patients with amnestic MCI (aMCI) and normal controls (NC). Methods 20 AD patients, 21 aMCIs and 25 NC were recruited in the study. FreeSurfer software was used to calculate cortical thickness and surface area among groups. Results The patients with AD had less cortical thickness both in the left and right hemisphere in 17 of the 36 brain regions examined than the patients with aMCI or NC. The patients with AD also had smaller cerebral surface area both in the left and right hemisphere in 3 of the 36 brain regions examined than the patients with aMCI or NC. Compared with the NC, the patients with aMCI only had slight atrophy in the inferior parietal lobe of the left hemisphere, and no significant difference was found. Conclusion AD, as well as aMCI (to a lesser extent), is associated with reduced cortical thickness and surface area in a few brain regions associated with cognitive impairment. These results suggest that cortical thickness and surface area could be used for early detection of AD. 展开更多
关键词 brain morphology CHANGE amnestic MILD COGNITIVE IMPAIRMENT compared aMCI NC
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Comparison of the oncological,perioperative and functional outcomes of partial nephrectomy versus radical nephrectomy for clinical T1b renal cell carcinoma:A systematic review and metaanalysis of retrospective studies 被引量:4
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作者 Yucong Zhang Gongwei Long +8 位作者 Haojie Shang Beichen Ding Guoliang Sun Wei Ouyang Man Liu Yuan Chen Heng Li hua xu Zhangqun Ye 《Asian Journal of Urology》 CSCD 2021年第1期117-125,共9页
Objective:To conduct a meta-analysis assessing the perioperative,functional and oncological outcomes of partial nephrectomy(PN)and radical nephrectomy(RN)for T1b tumours.The primary endpoints were the oncological outc... Objective:To conduct a meta-analysis assessing the perioperative,functional and oncological outcomes of partial nephrectomy(PN)and radical nephrectomy(RN)for T1b tumours.The primary endpoints were the oncological outcomes.The secondary endpoints were the perioperative and functional outcomes.Methods:A systematic literature review was performed by searching multiple databases through February 2019 to identify eligible comparative studies according to the Preferred Reporting Items for Systematic Review and Meta-analysis statement.Identified reports were assessed according to the Newcastle-Ottawa Scale for nonrandomized controlled trials.Results:Overall,13 retrospective cohort studies were included in the analysis.Patients undergoing PN were younger(weighted mean difference[WMD]3.49 years,95%confidence interval[CI]5.16 to1.82;p<0.0001)and had smaller masses(WMD0.45 cm,95%CI0.59 to0.31;p<0.0001).There were no differences in the oncological outcome,which was demonstrated by progression-free survival(hazard ratio[HR]0.70;pZ0.22),cancerspecific mortality(HR 0.91;pZ0.57)and all-cause mortality(HR 1.01;pZ0.96).The two procedures were similar in estimated blood loss(WMD16.47 mL;pZ0.53)and postoperative complications(risk ratio[RR]1.32;pZ0.10),and PN provided better renal function preservation and was related to a lower likelihood of chronic kidney disease onset(RR 0.38;pZ0.006).Conclusion:PN is an effective treatment for T1b tumours because it offers similar surgical morbidity,equivalent cancer control,and better renal preservation compared to RN. 展开更多
关键词 Kidney cancer Partial nephrectomy Radical nephrectomy Renal cancer SURVIVAL Renal function
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Chinese NGOs in action against HIV/AIDS 被引量:4
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作者 hua xu Yi ZENG Allen F ANDERSON 《Cell Research》 SCIE CAS CSCD 2005年第11期914-918,共5页
Chinese nongovernmental organizations (NGOs) have played a significant role in the battle against AIDS in the People’s Republic of China. This article provides a brief overview of the structure of these organizations... Chinese nongovernmental organizations (NGOs) have played a significant role in the battle against AIDS in the People’s Republic of China. This article provides a brief overview of the structure of these organizations, as well as an analysis of their principle accomplishments. Of great significance in this analysis is the fact that Chinese NGOs have effectively dealt with many sensitive health education areas that government authorities have felt reluctant to handle directly. As such, they have provided an indispensable component in the HIV/AIDS prevention and control calculus on the mainland. 展开更多
关键词 HIV/AIDS NGO health education health intervention
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Chinese Association for the Study of Pain:Experts consensus on ultrasound-guided injections for the treatment of spinal pain in China(2020 edition) 被引量:4
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作者 Yun Wang Ai-Zhong Wang +8 位作者 Bai-Shan Wu Yong-Jun Zheng Da-Qiang Zhao Hui Liu hua xu Hong-Wei Fang Jin-Yuan Zhang Zhi-Xiang Cheng Xiang-Rui Wang 《World Journal of Clinical Cases》 SCIE 2021年第9期2047-2057,共11页
Spinal pain(SP)is a common condition that has a major negative impact on a patient’s quality of life.Recent developments in ultrasound-guided injections for the treatment of SP are increasingly being used in clinical... Spinal pain(SP)is a common condition that has a major negative impact on a patient’s quality of life.Recent developments in ultrasound-guided injections for the treatment of SP are increasingly being used in clinical practice.This clinical expert consensus describes the purpose,significance,implementation methods,indications,contraindications,and techniques of ultrasound-guided injections.This consensus offers a practical reference point for physicians to implement successfully ultrasound-guided injections in the treatment of chronic SP. 展开更多
关键词 Spinal pain Ultrasound-guided injections Facet joints Spinal nerve roots Posterior spinal nerve Experts consensus
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Treatment of leiomyomatosis peritonealis disseminata with goserelin acetate: A case report and review of the literature 被引量:4
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作者 Jia-Wen Yang Yu hua +3 位作者 hua xu Liu He Hai-Zhong Huo Chen-Fang Zhu 《World Journal of Clinical Cases》 SCIE 2021年第19期5217-5225,共9页
BACKGROUND Leiomyomatosis peritonealis disseminata(LPD)is a rare condition characterized by multiple pelvic and abdominal nodules,which are composed of smoothmuscle cells.To date,no more than 200 cases have been repor... BACKGROUND Leiomyomatosis peritonealis disseminata(LPD)is a rare condition characterized by multiple pelvic and abdominal nodules,which are composed of smoothmuscle cells.To date,no more than 200 cases have been reported.The diagnosis of LPD is difficult and there are no guidelines on the treatment of LPD.Currently,surgical excision is the mainstay.However,hormone blockade therapy can be an alternative choice.CASE SUMMARY A 33-year-old female patient with abdominal discomfort and palpable abdominal masses was admitted to our hospital.She had undergone four surgeries related to uterine leiomyoma in the past 8 years.Computed tomography revealed multiple nodules scattered within the abdominal wall and peritoneal cavity.Her symptoms and the result of the core-needle biopsy were consistent with LPD.The patient refused surgery and was then treated with tamoxifen,ulipristal acetate(a selective progesterone receptor modulator),and goserelin acetate(a gonadotropin-releasing hormone agonist).Both tamoxifen and ulipristal acetate were not effective in controlling the disease progression.However,the patient achieved an excellent response when goserelin acetate was attempted with relieved syndromes and obvious shrinkage of nodules.The largest nodule showed a 25%decrease in the sum of the longest diameters from pretreatment to posttreatment.Up to now,2 years have elapsed and the patient remains asymptomatic and there is no development of further nodules.CONCLUSION Goserelin acetate is effective for the management of LPD.The long-term use of goserelin acetate is thought to be safe and effective.Hormone blockade therapy can replace repeated surgical excision in recurrent patients. 展开更多
关键词 Goserelin acetate Leiomyomatosis peritonealis disseminata Hormone blockade therapy Conservative treatment Disseminated peritoneal leiomyomatosis Case report
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Foveal structure changes in infants treated with anti-VEGF therapy or laser therapy guided by optical coherence tomography angiography for retinopathy of prematurity 被引量:4
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作者 xun Deng Yong Cheng +3 位作者 xue-Mei Zhu Dan-Dan Linghu hua xu Jian-Hong Liang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第1期106-112,共7页
AIM: To evaluate foveal vessel density(VD) and foveal thickness using optical coherence tomography angiography(OCTA) in retinopathy of prematurity(ROP) children treated with laser photocoagulation or anti-vascular end... AIM: To evaluate foveal vessel density(VD) and foveal thickness using optical coherence tomography angiography(OCTA) in retinopathy of prematurity(ROP) children treated with laser photocoagulation or anti-vascular endothelial growth factor(VEGF) injection. Additionally, we assessed the relationship between foveal microvascular anomalies and different therapies in ROP children.METHODS: This was a single-center, retrospective study of patients with a diagnosis of type 1 ROP. Twenty-three eyes(14 patients) treated with anti-VEGF injection and twentynine eyes(17 patients) treated with laser coagulation were included in this study. The foveal VD, inner thickness and full thickness were measured at the central 0°, 2° to 8°, and 8° of the retina(centered on the fovea) using OCTA and cross-sectional OCT, respectively.RESULTS: Foveal VD, inner thickness and full thickness were significantly smaller within the central 8° of the retina in ROP children treated with anti-VEGF injection than in those treated with laser photocoagulation(P=0.013, 0.009, 0.036, respectively). The full thickness was also smaller in the anti-VEGF group than in the laser group at the central 0° of the retina(P=0.010). The grade of foveal hypoplasia is lower in the anti-VEGF group than in the laser group(P=0.045). Multivariable analysis did not find any risk factors associated with visual acuity in our study.CONCLUSION: In children with type 1 ROP, the better structural development of fovea in those who were treated with anti-VEGF injection compared with laser photocoagulation are identified. However, visual acuity outcomes are similar 70 mo after the treatments. 展开更多
关键词 retinopathy of prematurity optical coherence tomography angiography anti-vascular endothelial growth factor laser photocoagulation
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