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Te-Modulated Fe Single Atom with Synergistic Bidirectional Catalysis for High-Rate and Long-Cycling Lithium-Sulfur Battery
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作者 Jian Guo Lu Chen +4 位作者 lijun wang Kangfei Liu Ting He Jia Yu Hongbin Zhao 《Nano-Micro Letters》 2026年第1期827-842,共16页
Single-atom catalysts(SACs)have garnered significant attention in lithium-sulfur(Li-S)batteries for their potential to mitigate the severe polysulfide shuttle effect and sluggish redox kinetics.However,the development... Single-atom catalysts(SACs)have garnered significant attention in lithium-sulfur(Li-S)batteries for their potential to mitigate the severe polysulfide shuttle effect and sluggish redox kinetics.However,the development of highly efficient SACs and a comprehensive understanding of their structure-activity relationships remain enormously challenging.Herein,a novel kind of Fe-based SAC featuring an asymmetric FeN_(5)-TeN_(4) coordination structure was precisely designed by introducing Te atom adjacent to the Fe active center to enhance the catalytic activity.Theoretical calculations reveal that the neighboring Te atom modulates the local coordination environment of the central Fe site,elevating the d-band center closer to the Fermi level and strengthening the d-p orbital hybridization between the catalyst and sulfur species,thereby immobilizing polysulfides and improving the bidirectional catalysis of Li-S redox.Consequently,the Fe-Te atom pair catalyst endows Li-S batteries with exceptional rate performance,achieving a high specific capacity of 735 mAh g^(−1) at 5 C,and remarkable cycling stability with a low decay rate of 0.038%per cycle over 1000 cycles at 1 C.This work provides fundamental insights into the electronic structure modulation of SACs and establishes a clear correlation between precisely engineered atomic configurations and their enhanced catalytic performance in Li-S electrochemistry. 展开更多
关键词 Single-atom catalyst Coordination environment Electronic structure Bidirectional catalysis Li-S batteries
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Burden of Headache Disorders in China and its Provinces,1990-2021 被引量:1
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作者 Zhe Liu Xuehua Hu +5 位作者 Lin Yang Jinlei Qi Jiangmei Liu lijun wang Maigeng Zhou Peng Yin 《Biomedical and Environmental Sciences》 2025年第5期547-556,共10页
Objective To analyze the prevalence and burden of headache disorders in China and its provinces from 1990 to 2021.Methods Using data from the Global Burden of Disease Study(GBD)2021,the number of prevalent cases,preva... Objective To analyze the prevalence and burden of headache disorders in China and its provinces from 1990 to 2021.Methods Using data from the Global Burden of Disease Study(GBD)2021,the number of prevalent cases,prevalence rate,disability-adjusted life years(DALYs),and age-standardized DALY rates were analyzed by sex,age group,and province for headache disorders and their subtypes(migraine and tension-type headache[TTH])between 1990 and 2021.Percentage changes during this period were also estimated.Results In 2021,approximately 426 million individuals in China were affected by headache disorders,with an age-standardized prevalence rate of 27,582.61/100,000.The age-standardized DALY rate for all headache disorders was 487.15/100,000.Between 1990 and 2021,the number of prevalent cases increased by 37.78%,while the prevalence of all headache disorders,migraine,and TTH increased by 6.92%,7.57%,and 7.86%,respectively.The highest prevalence was observed in the 30-34 age group(39,520.60/100,000).Migraine accounted for a larger proportion of DALYs attributable to headache disorders,whereas TTH has a greater impact on its prevalence.In 2021,the highest age-standardized DALY rates for headache disorders were observed in Heilongjiang(617.85/100,000)and Shanghai(542.86/100,000).Conclusion The prevalence of headache disorders is increasing in China.Effective health education,improve diagnosis and treatment are essential,particularly for middle-aged working populations and women of childbearing age. 展开更多
关键词 Headache disorders MIGRAINE Tension-type headache Global burden of disease study
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Pharmacobezoars:the challenges of gastric lavage for a patient with drug overdose 被引量:1
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作者 Hao wang Qing Tang +5 位作者 Shuxin Hua Shuai Su Chongwen Bi Jiaqi Xu Yanfen Chai lijun wang 《World Journal of Emergency Medicine》 2025年第2期186-188,共3页
Drug overdose is a common reason for emergency department admissions.Although pharmacobezoars due to drug overdose are rare,they can increase the length of hospital stay and risk of mortality.^([1]) Currently,no clear... Drug overdose is a common reason for emergency department admissions.Although pharmacobezoars due to drug overdose are rare,they can increase the length of hospital stay and risk of mortality.^([1]) Currently,no clear procedure for the management of gastric pharmacobezoars exists.We report a case of a patient with pharmacobezoars caused by high-dose oral drug poisoning.The patient recovered completely after gastroscopy,gastric lavage,and symptomatic treatments. 展开更多
关键词 LAVAGE PATIENT GASTRIC
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MicroRNAs in heart and circulation during physical exercise 被引量:8
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作者 lijun wang Yicheng Lv +1 位作者 Guoping Li Junjie Xiao 《Journal of Sport and Health Science》 SCIE 2018年第4期433-441,共9页
Exercise training is beneficial to the cardiovascular system. MicroRNAs (miRNAs, miRs) are a class of conserved non-coding RNAs and play a wide-ranging role in the regulation of eukaryotic gene expression. Exercise ... Exercise training is beneficial to the cardiovascular system. MicroRNAs (miRNAs, miRs) are a class of conserved non-coding RNAs and play a wide-ranging role in the regulation of eukaryotic gene expression. Exercise training alters the expression levels of large amounts ofmiRNAs in the heart. In addition, circulating miRNAs appear to be regulated by exercise training. In this review, we will summarize recent advances in the regulation of miRNAs during physical exercise intervention in various cardiovascular diseases, including pathologic cardiac hypertrophy, myocardial fibrosis, ischemia-reperfusion injury, myocardial infarction, and heart failure. The regulatory role of circulating miRNAs after exercise training was also reviewed. In conclusion, miRNAs might be a valuable target for treatment of cardiovascular diseases and have great potential as biomarkers for assessment of physical performance.2018 Published by Elsevier B.V.on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Cardiovascular diseases Circulating microRNAs EXERCISE MICRORNAS
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增塑剂对聚氯乙烯溶胶凝胶塑化流变性能的影响 被引量:9
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作者 吉玉碧 王醴均 +4 位作者 杨照 石敏 罗恒 龚维 谭红 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第1期64-69,共6页
研究了不同增塑剂制备的聚氯乙烯(PVC)溶胶复数黏度(η)随温度或时间的流变性能变化情况,并探讨了引起流变性能差异的原因。结果表明,随温度升高或时间延长,η呈先降低,后由缓慢上升至急速上升,形成1个肩峰并达到最大值,最后又逐步减小... 研究了不同增塑剂制备的聚氯乙烯(PVC)溶胶复数黏度(η)随温度或时间的流变性能变化情况,并探讨了引起流变性能差异的原因。结果表明,随温度升高或时间延长,η呈先降低,后由缓慢上升至急速上升,形成1个肩峰并达到最大值,最后又逐步减小的非正态分布趋势。各PVC溶胶在流变曲线的前3个阶段,η差异明显——第1阶段,η主要与增塑剂黏度成正比;第2、第3阶段——η主要与增塑剂的增塑效率和溶解度参数有关;第4阶段——约在160℃或30min后,各流变曲线趋于重合,η的大小无明显差异。 展开更多
关键词 聚氯乙烯 溶胶 增塑剂 流变 黏度
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代谢改造重组谷氨酸棒杆菌C4途径高效合成5-氨基乙酰丙酸 被引量:6
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作者 王丽君 闫思翰 +5 位作者 杨套伟 徐美娟 张显 邵明龙 李华钟 饶志明 《生物工程学报》 CAS CSCD 北大核心 2021年第12期4314-4328,共15页
5-氨基乙酰丙酸(5-aminolevulinic acid,5-ALA)在医药和农业等领域有着广泛作用,目前主要采用大肠杆菌或谷氨酸棒杆菌以微生物发酵法合成。为了进一步提高谷氨酸棒杆菌合成5-ALA的能力,对其C4代谢途径进行了系统代谢改造。首先分别在谷... 5-氨基乙酰丙酸(5-aminolevulinic acid,5-ALA)在医药和农业等领域有着广泛作用,目前主要采用大肠杆菌或谷氨酸棒杆菌以微生物发酵法合成。为了进一步提高谷氨酸棒杆菌合成5-ALA的能力,对其C4代谢途径进行了系统代谢改造。首先分别在谷氨酸棒杆菌中异源表达荚膜红杆菌和沼泽红假单胞菌的5-氨基乙酰丙酸合成酶ALAS,选择酶活相对较高的沼泽红假单胞菌的RphemA基因作为关键合成酶基因,并筛选到能显著增强RphemA的酶活性的核糖体结合位点RBS5。重组菌株ALAS的比酶活可达(221.87±3.10)U/mg,且5-ALA产量提高了14.3%;随后通过敲除α-酮戊二酸脱氢酶抑制蛋白基因(odhI)和琥珀酸脱氢酶基因(sdhA),促进了前体琥珀酰CoA向5-ALA途径的流动;通过sRNA抑制hemB表达减少了5-ALA的降解;并且过表达半胱氨酸/O-乙酰丝氨酸转运蛋白eamA提高了5-ALA的输出效率;使用重组菌株C.glutamicum13032/?odhI/?sdhA-sRNAhemB-RBS5RphemA-eamA摇瓶发酵,5-ALA最高产量达11.90g/L,较出发菌株提高了57%。最后,在5L发酵罐中进行补料分批发酵,48h内5-ALA的产量达25.05g/L,为目前以葡萄糖为碳源发酵的最高产量。本研究构建了高产5-ALA重组谷氨酸棒杆菌,具有良好的工业应用前景。 展开更多
关键词 谷氨酸棒杆菌 5-氨基乙酰丙酸 代谢改造 C4途径
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1173例淋巴瘤患者死亡原因调查 被引量:5
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作者 韩森 刘卫平 +6 位作者 季新强 方健 刘江美 殷鹏 王黎君 周脉耕 朱军 《中国肿瘤临床》 CAS CSCD 北大核心 2019年第9期447-451,共5页
目的:分析淋巴瘤患者人群的死亡原因和长期预后情况。方法:收集北京大学肿瘤医院1995年1月至2017年12月收治的6 200例淋巴瘤患者的基线资料,筛选其中已经发生死亡且死亡原因已知的患者,并收集其临床资料和死亡信息。结果:共筛选出1173... 目的:分析淋巴瘤患者人群的死亡原因和长期预后情况。方法:收集北京大学肿瘤医院1995年1月至2017年12月收治的6 200例淋巴瘤患者的基线资料,筛选其中已经发生死亡且死亡原因已知的患者,并收集其临床资料和死亡信息。结果:共筛选出1173例患者,其中男性742例(63.3%),女性431例(36.7%)。中位年龄为56(8~ 92)岁。霍奇金淋巴瘤(Hodgkin's lymphoma,HL) 77例(6.6%),非霍奇金淋巴瘤(non-Hodgkin's lymphoma,NHL) 1095例(93.4%),病理分类不明确1例。总体人群生存期为0~ 253个月,中位生存期为20个月。直接死亡原因包括淋巴瘤688例(58.7%),各类感染性疾病119例(10.1%),心血管疾病(car diovascular disease,CVD) 96例(8.2%),第二原发肿瘤68例(5.8%),其他疾病202例(17.2%)。根本死亡原因包括淋巴瘤936例(79.8%),第二原发肿瘤94例(8.0%), CVD75例(6.4%),呼吸系统疾病32例(2.7%)和其他疾病36例(3.1%)。生存期超过5年的217例患者根本死亡原因为淋巴瘤129例(59.4%),第二原发肿瘤38例(17.5%), CVD35例(16.1%)和其他疾病15例(6.9%)。生存期超过10年的60例患者根本死亡原因为淋巴瘤28例(46.7%),第二原发肿瘤17例(28.3%), CVD7例(11.7%)和其他疾病8例(13.3%)。结论:原发肿瘤仍是淋巴瘤患者死亡的主要原因。第二原发肿瘤和CVD是除原发肿瘤以外最常见的死亡原因,并且随着生存期的延长,二者所致的死亡风险明显增加。 展开更多
关键词 淋巴瘤 死亡原因 第二原发肿瘤 心血管病 肿瘤心脏病学
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Mechanism of Piezo1 regulating chondrocyte mitochondrial function and promoting fracture healing through β-catenin/LARS2 signaling pathway
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作者 Tao Zhang Hongzhi Lv +10 位作者 Siming Jia lijun wang Weijian Liu Kai Ding Xiaofeng Du Guangzhao Hou Zhiyong Hou Yingze Zhang Weiguo Zou Wei Chen Yanbin Zhu 《Bone Research》 2025年第5期1308-1325,共18页
Piezo1,a key mechanosensor in bone homeostasis,plays a crucial role in fracture healing.However,the mechanisms through which Piezo1 regulates chondrocytes and affects endochondral ossification remain poorly understood... Piezo1,a key mechanosensor in bone homeostasis,plays a crucial role in fracture healing.However,the mechanisms through which Piezo1 regulates chondrocytes and affects endochondral ossification remain poorly understood.This study aimed to investigate the regulatory mechanisms of Piezo1 in chondrocytes during endochondral ossification.Using lineage tracing,we identified chondrocyte-to-osteoblast transdifferentiation during endochondral ossification,which was impaired by chondrocyte-specific Piezo1 knockout.Piezo1 deficiency disrupted mitochondrial bioenergetics,characterized by diminished membrane potential,reduced adenosine triphosphate(ATP)synthesis,suppressed oxygen consumption rates(basal and maximal respiration),and elevated mitochondrial superoxide generation,thereby impairing endochondral ossification during fracture healing.Single-cell RNA sequencing revealed upregulated Lars2 expression in hypertrophic chondrocytes following Piezo1 knockout.Inhibition of Lars2 in chondrocytes normalized mitochondrial dynamics-related markers(MFN1,MFN2,OPA1,DRP1)and restored mitochondrial functional homeostasis.This intervention concurrently reversed Piezo1 knockout-induced suppression of osteogenic markers(Col1,ALP,OCN,OPN,RUNX2),thereby enhancing fracture repair.Protein interaction analyses confirmed direct binding betweenβ-catenin and Lars2.Mechanistically,Piezo1 governs Lars2 expression viaβ-catenin signaling.Our findings demonstrate that Piezo1 activation via Yoda1 enhances mitochondrial bioenergetics and accelerates fracture repair through theβ-catenin/Lars2 axis,offering novel insights and therapeutic avenues for fracture treatment. 展开更多
关键词 CHONDROCYTES lineage tracingwe piezo bone homeostasisplays endochondral ossificationusing endochondral ossification endochondral ossificationwhich fracture healinghoweverthe
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A quasi-in-situ EBSD study on mechanical response and twin variant selection of a hot-rolled AZ31 magnesium alloy
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作者 Huicong Chen Chenwei Shao +2 位作者 lijun wang Hao Chen Yu Zou 《Journal of Magnesium and Alloys》 2025年第4期1549-1560,共12页
The selection of twin variants plays a critical role in shaping the deformation texture and mechanical properties of magnesium alloys that are limited by slip systems and diverse twinning modes.In this study,we invest... The selection of twin variants plays a critical role in shaping the deformation texture and mechanical properties of magnesium alloys that are limited by slip systems and diverse twinning modes.In this study,we investigated the twin variant selection and the effect of twinning activity on the strain hardening of a hot-rolled AZ31 magnesium alloy by quasi-in-situ EBSD.Moreover,the Schmid factors and the displacement gradient tensors were computed to evaluate the activation of twin variants.The results reveal that the yield strength increased progressively after each deformation step,driven by grain subdivision and texture hardening induced by extension{1012}twinning and the Basinski effect at large strains.The nucleation and growth of the{1012}twins occurred either sequentially or simultaneously during the plastic deformation.At low plastic strains,the activation of most twin variants followed the high Schmid factor criterion while the other twin variants with lower Schmid factors were activated due to the interactions with preexisting twins characterized by high misorientation angles(around 60°).Additionally,this non-Schmid factor scenario was also attributed to low coordinated strain requirements from neighboring grains,showing the critical role of local deformation accommodation in the twinning process.These findings advance the fundamental understanding of the twin variant selection and its implications for the microstructure-property relationship in magnesium alloys for structural applications. 展开更多
关键词 Magnesium alloy Strain hardening Twin variants Schmid factor Strain accommodation
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VANETs group message secure forwarding with trust evaluation
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作者 lijun wang Huajie Hao +1 位作者 Chun wang Xianzhou Han 《Digital Communications and Networks》 2025年第4期1149-1156,共8页
Efficient and safe information exchange between vehicles can reduce the probability of road accidents,thereby improving the driving experience of vehicles in Vehicular Ad Hoc Networks(VANETs).This paper proposes a gro... Efficient and safe information exchange between vehicles can reduce the probability of road accidents,thereby improving the driving experience of vehicles in Vehicular Ad Hoc Networks(VANETs).This paper proposes a group management algorithm with trust and mobility evaluation to address the enormous pressure on VANETs topology caused by high-speed vehicle movement and dynamic changes in the direction of travel.This algorithm utilizes historical interactive data to mine the fusion trust between vehicles.Then,combined with fusion mobility,the selection of center members and information maintenance of group members is achieved.Furthermore,based on bilinear pairing,an encryption protocol is designed to solve the problem of key management and update when the group structure changes rapidly,ensuring the safe forwarding of messages within and between groups.Numerical analysis shows that the algorithm in the paper ensures group stability and improves performance such as average message delivery rate and interaction delay. 展开更多
关键词 Vehicular ad hoc networks Trust evaluation Group management Double key encryption
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Risk factors for death in patients with acute diquat poisoning
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作者 Qing Tang Hongxin wang +5 位作者 Hao wang Jiaqi Xu Xin Luo Shuxin Hua lijun wang Yanfen Chai 《World Journal of Emergency Medicine》 2025年第3期225-230,共6页
BACKGROUND:In recent years,with the ban on paraquat,the use of diquat (DQ) as a substitute has significantly increased,leading to a corresponding increase in DQ poisoning cases.This study aimed to identify relevant ri... BACKGROUND:In recent years,with the ban on paraquat,the use of diquat (DQ) as a substitute has significantly increased,leading to a corresponding increase in DQ poisoning cases.This study aimed to identify relevant risk factors affecting patient prognosis and provide a basis for the assessment of patient prognosis.METHODS:Patients with DQ poisoning were included from September 2020 to December2023,and data were extracted from their electronic medical records on the first day of hospitalization.Least Absolute Shrinkage and Selection Operator (LASSO) regression and binary multivariate logistic regression analyses were performed on the collected clinical data to identify risk factors.RESULTS:A total of 117 patients with acute DQ poisoning were included,and were categorized into two groups based on their 28-day outcomes:survival group (n=67) and non-survival group (n=50).There were no statistically significant differences between the two groups in terms of sex,lymphocyte count,platelet-to-lymphocyte ratio,or blood purification rate (P>0.05).The analysis revealed that age (odds ratio[OR]1.094,95%confidence interval[95%CI]1.022–1.171),blood drug concentration (OR 3.659,95%CI1.846–7.252),lactate (OR 1.686,95%CI 1.062–2.678),neutrophil-to-lymphocyte ratio (NLR)(OR 1.101,95%CI 1.017–1.192),albumin (OR 1.275,95%CI 1.107–1.468),and aspartate aminotransferase (AST)(OR 1.027,95%CI 1.005–1.051) were the risk factors for mortality.CONCLUSION:This study identified key risk factors for 28-day mortality in patients with acute DQ poisoning,which may provide valuable guidance for clinical treatment,particularly for emergency physicians. 展开更多
关键词 Acute diquat poisoning PROGNOSIS Risk factor Retrospective study
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大豆蛋白增强水凝胶电解质的制备及在全固态超级电容器上的应用
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作者 南静娅 张盖同 +3 位作者 王利军 汪宏生 储富祥 王春鹏 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第3期143-150,共8页
以聚丙烯酰胺链交联形成三维网状结构,通过大豆蛋白纳米粒子与聚丙烯酰胺之间的静电引力,将大豆蛋白引入聚丙烯酰胺交联网络中,经磷酸溶液置换,得到一种水凝胶电解质。大豆蛋白纳米粒子与聚丙烯酰胺分子链之间的协同作用,使得水凝胶在80... 以聚丙烯酰胺链交联形成三维网状结构,通过大豆蛋白纳米粒子与聚丙烯酰胺之间的静电引力,将大豆蛋白引入聚丙烯酰胺交联网络中,经磷酸溶液置换,得到一种水凝胶电解质。大豆蛋白纳米粒子与聚丙烯酰胺分子链之间的协同作用,使得水凝胶在80%应变时进行100次的循环压缩后未发生结构断裂或损坏;以水凝胶电解质为固体电解质,以聚吡咯-碳纳米管纸为电极,组装成对称结构的全固态超级电容器。组装的全固态超级电容器具有优异的电化学性能,最大能量密度为6.2 W·h/kg,最大功率密度为398.4 W/kg。更重要的是,器件整体可承受80%的压缩应变而未产生断裂或损坏,并表现出良好的电容稳定性. 展开更多
关键词 大豆蛋白 水凝胶 电解质 超级电容器 电容稳定性
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Acute Uveitis in Neovascular Glaucoma Patient after a Single Dose of Travoprost
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作者 lijun wang Jing Zhu +1 位作者 Qian Feng Junfeng Yang 《Case Reports in Clinical Medicine》 2024年第8期275-282,共8页
A 38-year-old man with no history of uveitis developed neovascular glaucoma (NVG) due to proliferative diabetic retinopathy (PDR). He had a history of ocular surgery with placement of glaucoma drainage implants (GDI),... A 38-year-old man with no history of uveitis developed neovascular glaucoma (NVG) due to proliferative diabetic retinopathy (PDR). He had a history of ocular surgery with placement of glaucoma drainage implants (GDI), ultrasonic phacoemulsification, and intraocular lens implantation in both eyes. The patient had undergone a recent pars plana vitrectomy with complete panretinal photocoagulation (PRP) to clear vitreous hemorrhage in his right eye. To prevent progressive optic nerve damage, travoprost was tentatively administered because of inadequate intraocular pressure (IOP) control following surgery, laser treatment, and topical administration of many other IOP-lowering drugs. The patient experienced severe vision loss associated with acute anterior and intermediate uveitis. We consider it a rare complication due to the NVG patient’s vulnerability following ocular surgery. Given that acute uveitis developed rapidly and required time to resolve, systemic corticosteroid treatment could be considered to accelerate the resolution of inflammation. 展开更多
关键词 TRAVOPROST UVEITIS GLAUCOMA Prostaglandin Analogues Intraocular Pressure
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七子花内生真菌的抗菌活性筛选及其活性先导化合物的发现(英文) 被引量:3
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作者 王丽君 陈婷婷 +3 位作者 邹园园 朱蔓莉 余文华 张应烙 《微生物学报》 CAS CSCD 北大核心 2015年第1期33-39,共7页
【目的】从濒危植物七子花中分离出具有抗植物致病菌活性的内生真菌,并在其代谢产物中寻找具有抗菌活性的先导化合物。【方法】采用生长速率法测定内生真菌对植物病原菌的抑制活性。通过形态学和5.8S rRNA序列法对具有较好抗菌活性的内... 【目的】从濒危植物七子花中分离出具有抗植物致病菌活性的内生真菌,并在其代谢产物中寻找具有抗菌活性的先导化合物。【方法】采用生长速率法测定内生真菌对植物病原菌的抑制活性。通过形态学和5.8S rRNA序列法对具有较好抗菌活性的内生真菌进行鉴定。运用多种色谱方法对发酵产物进行分离、纯化,利用质谱和核磁共振谱分析鉴定出化合物的结构。【结果】茄交链孢QZH 10对水稻纹枯病菌和苹果树腐烂病菌的抑制活性较好,抑制率分别为89.1%和67.9%。在供试浓度为100μg/m L时,QZH 10乙酸乙酯粗提物对稻瘟病菌具有强烈的抑制效果,抑制率为100.0%。从QZH 10中分离到2个单体化合物并分别被鉴定为altersolanol A和6-O-methylalaternin。在供试浓度为100μg/m L时,altersolanol A对稻瘟病菌具有较强的抑制效果,抑制率大于85%;6-O-methylalaternin对苹果树腐烂病菌具有强烈的抑制效果,抑制率为100.0%。【结论】当前结果表明Altersolanol A和6-O-methylalaternin具有开发成微生物源杀菌剂的潜力。 展开更多
关键词 七子花 茄交链孢 内生真菌 抗菌活性 天然产物
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用原位聚合法制备的PA6/GO纳米复合材料的结构和性能 被引量:4
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作者 黄欢 陈宇哲 +5 位作者 郭怡 蔺海兰 王丽君 马素德 卞军 谷志杰 《材料研究学报》 EI CAS CSCD 北大核心 2019年第8期621-628,共8页
以己内酰胺(CL)和6-氨基己酸(ACA)为聚合反应单体,用Hummers法制备氧化石墨烯(GO),再以GO为纳米填料用原位开环聚合法制备了GO改性PA6纳米复合材料(PA6/GO),并对PA6/GO纳米复合材料的结构及性能进行了研究。结果表明,PA6的黏均分子量达... 以己内酰胺(CL)和6-氨基己酸(ACA)为聚合反应单体,用Hummers法制备氧化石墨烯(GO),再以GO为纳米填料用原位开环聚合法制备了GO改性PA6纳米复合材料(PA6/GO),并对PA6/GO纳米复合材料的结构及性能进行了研究。结果表明,PA6的黏均分子量达到104数量级,但加入过多的GO使PA6的分子量降低。形貌分析表明,GO均匀地分散在PA6基体中,并诱导了PA6基体的晶型由α晶型转变成γ晶型。同时,GO作为异相成核剂促进了PA6/GO复合材料中PA6基体的结晶,提高了PA6/GO复合材料的结晶度。拉伸测试结果表明,随着GO的加入PA6/GO纳米复合材料的拉伸强度先提高后降低,GO加入量为0.4份时拉伸强度达到最大值61.72 MPa,比纯PA6(48.52 MPa)提高了27.21%。导热性能分析表明含1.0份GO的PA6/GO纳米复合材料其50℃和100℃的热导率分别为0.317 W/(m·K)和0.280 W/(m·K),较纯PA6分别提高了33.19%和33.23%。 展开更多
关键词 复合材料 尼龙6(PA6) 氧化石墨烯(GO) 力学性能 导热性能
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反事实分析+过程追踪:社会科学因果推断的整合进路 被引量:5
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作者 王利君 于文轩 黄英 《公共行政评论》 CSSCI 北大核心 2024年第4期177-194,M0008,共19页
因果推断存在多种途径,然而近来兴起的因果推断讨论却明显倒向了“反事实分析”。为了帮助形成更加完整的因果推断认识,论文从因果本体论、认识论出发,结合因果推断的形式与类型,梳理出反事实分析与过程追踪两种因果推断途径,论证它们... 因果推断存在多种途径,然而近来兴起的因果推断讨论却明显倒向了“反事实分析”。为了帮助形成更加完整的因果推断认识,论文从因果本体论、认识论出发,结合因果推断的形式与类型,梳理出反事实分析与过程追踪两种因果推断途径,论证它们的因果推断比较优势及其互补性,指出反事实分析和过程追踪分别在识别因果关系和挖掘因果机制上占据比较优势,只有将二者结合,才能对因果形成较全面的理解。对此,文章以中国的治理场景为例,选取制度创新与制度效能转化、政策创新生成两个研究情境,论述了反事实分析和过程追踪的结合何以帮助理解中国之治。论文有助于完善因果推断三角研究,讲好中国故事,同时对于推进社会科学研究方法的纵深思考也具有参考价值。 展开更多
关键词 因果推断三角 反事实分析 过程追踪 中国故事
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Mechanical regulation of bone remodeling 被引量:37
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作者 lijun wang Xiuling You +2 位作者 Lingli Zhang Changqing Zhang Weiguo Zou 《Bone Research》 SCIE CAS CSCD 2022年第1期31-45,共15页
Bone remodeling is a lifelong process that gives rise to a mature, dynamic bone structure via a balance between bone formation by osteoblasts and resorption by osteoclasts. These opposite processes allow the accommoda... Bone remodeling is a lifelong process that gives rise to a mature, dynamic bone structure via a balance between bone formation by osteoblasts and resorption by osteoclasts. These opposite processes allow the accommodation of bones to dynamic mechanical forces, altering bone mass in response to changing conditions. Mechanical forces are indispensable for bone homeostasis;skeletal formation, resorption, and adaptation are dependent on mechanical signals, and loss of mechanical stimulation can therefore significantly weaken the bone structure, causing disuse osteoporosis and increasing the risk of fracture. The exact mechanisms by which the body senses and transduces mechanical forces to regulate bone remodeling have long been an active area of study among researchers and clinicians. Such research will lead to a deeper understanding of bone disorders and identify new strategies for skeletal rejuvenation. Here, we will discuss the mechanical properties, mechanosensitive cell populations, and mechanotransducive signaling pathways of the skeletal system. 展开更多
关键词 FORCES STRUCTURE DYNAMIC
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High powerλ~8.5μm quantum cascade laser grown by MOCVD operating continuous-wave up to 408 K 被引量:13
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作者 Teng Fei Shenqiang Zhai +10 位作者 Jinchuan Zhang Ning Zhuo Junqi Liu lijun wang Shuman Liu Zhiwei Jia Kun Li Yongqiang Sun Kai Guo Fengqi Liu Zhanguo wang 《Journal of Semiconductors》 EI CAS CSCD 2021年第11期55-60,共6页
Robust quantum cascade laser(QCL)enduring high temperature continuous-wave(CW)operation is of critical importance for some applications.We report on the realization of lattice-matched InGaAs/InAlAs/InP QCL materials g... Robust quantum cascade laser(QCL)enduring high temperature continuous-wave(CW)operation is of critical importance for some applications.We report on the realization of lattice-matched InGaAs/InAlAs/InP QCL materials grown by metal-organic chemical vapor deposition(MOCVD).High interface quality structures designed for light emission at 8.5μm are achieved by optimizing and precise controlling of growth conditions.A CW output power of 1.04 W at 288 K was obtained from a 4 mm-long and 10μm-wide coated laser.Corresponding maximum wall-plug efficiency and threshold current density were 7.1%and 1.18 kA/cm2,respectively.The device can operate in CW mode up to 408 K with an output power of 160 mW. 展开更多
关键词 quantum cascade laser metal-organic chemical vapor deposition CONTINUOUS-WAVE interface roughness
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Magnetic resonance imaging with three-dimensional fast imaging employing steady-state acquisition with phase-cycled and short T1 inversion recovery pulse sequence for evaluating brachial plexus injury 被引量:7
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作者 Dianxiu Ning Meiyu Sun +11 位作者 Bo Sun Li Zhao Weisheng Zhang lijun wang Shaowu wang Ailian Liu Jianlin Wu Zhijin Lang Di Ning Guanfu Liu Xiaochen Ji Xiufeng wang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第14期1097-1102,共6页
There is a large amount of fat in the postganglionic segment of the brachial plexus nerve.The use of short T1 inversion recovery pulse sequence may improve signal strength of the brachial plexus postganglionic segment... There is a large amount of fat in the postganglionic segment of the brachial plexus nerve.The use of short T1 inversion recovery pulse sequence may improve signal strength of the brachial plexus postganglionic segment.The present study revealed that the combination of three-dimensional fast imaging employing steady-state acquisition with phase-cycled and short T1 inversion recovery pulse sequence clearly displayed the anatomical morphology and structure of the brachial plexus nerve,together with maximum intensity projection,volume rendering and other three-dimensional reconstruction techniques.Our results suggested that this method is also suitable for providing accurate assessment and diagnosis of the site,severity and scope of brachial plexus injury. 展开更多
关键词 brachial plexus i-njury magnetic resonance imaging pulse sequence reconstruction
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Synthesis of nitrogen-doped carbon nanotubes-FePO_4 composite from phosphate residue and its application as effective Fenton-like catalyst for dye degradation 被引量:5
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作者 Lianmei Wei Yi Zhang +4 位作者 Shengwen Chen Luping Zhu Xiaoyu Liu Lingxue Kong lijun wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第2期188-198,共11页
Phosphate residue is regarded as a hazardous waste, which could potentially create significant environmental and health problems if it is not properly treated and disposed of. In this study, nitrogen-doped carbon nano... Phosphate residue is regarded as a hazardous waste, which could potentially create significant environmental and health problems if it is not properly treated and disposed of. In this study, nitrogen-doped carbon nanotubes-FePO_4(NCNTs-FePO_4) composite was successfully synthesized from phosphate residue, and its application as an effective catalyst was explored. Firstly, an effective method was developed to recover FePO_4 from phosphate residue, achieving an impressive FePO_4 mass recovery rate of 98.14%. Then, the NCNTsFePO_4 catalyst was synthesized from the recovered FePO_4 by two main reactions, including surface modification and chemical vapor deposition. Finally, the synthesized NCNTs-FePO_4 was applied to photo-degrade 15 mg/L Rhodamine B(RhB) in a Fenton-like system. The results showed that 98.9% of RhB could be degraded in 60 min, closely following the pseudofirst-order kinetics model. It was found that even after six consecutive cycles, NCNTs-FePO_4 still retained a high catalytic capacity(>50%). Moreover, ·OH radicals participating in the RhB degradation process were evidenced using quenching experiments and electron paramagnetic resonance analysis, and a rational mechanism was proposed. It was demonstrated that the materials synthesized from hazardous phosphate residue can be used as an effective catalyst for dye removal. 展开更多
关键词 Phosphate residue FENTON-LIKE NITROGEN-DOPED carbon nanotubes-FePO4 HYDROXYL radical
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