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Ferroptosis mechanism and Alzheimer's disease
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作者 Lina Feng Jingyi Sun +6 位作者 Ling Xia Qiang Shi Yajun Hou lili zhang Mingquan Li Cundong Fan Baoliang Sun 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1741-1750,共10页
Regulated cell death is a genetically determined form of programmed cell death that commonly occurs during the development of living organisms.This process plays a crucial role in modulating homeostasis and is evoluti... Regulated cell death is a genetically determined form of programmed cell death that commonly occurs during the development of living organisms.This process plays a crucial role in modulating homeostasis and is evolutionarily conserved across a diverse range of living organisms.Ferroptosis is a classic regulatory mode of cell death.Extensive studies of regulatory cell death in Alzheimer’s disease have yielded increasing evidence that fe rroptosis is closely related to the occurrence,development,and prognosis of Alzheimer’s disease.This review summarizes the molecular mechanisms of ferroptosis and recent research advances in the role of ferro ptosis in Alzheimer’s disease.Our findings are expected to serve as a theoretical and experimental foundation for clinical research and targeted therapy for Alzheimer’s disease. 展开更多
关键词 Alzheimer’s disease apolipoprotein E Fe^(2+) ferroptosis glial cell glutathione peroxidase 4 imbalance in iron homeostasis lipid peroxidation regulated cell death system Xc^(-)
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The wheat sucrose synthase gene TaSus1 is a determinant of grain number per spike
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作者 Liping Shen lili zhang +20 位作者 Changbin Yin Xiaowan Xu Yangyang Liu Kuocheng Shen He Wu Zhiwen Sun Ke Wang Zhonghu He Xueyong zhang Chenyang Hao Jian Hou Aoyue Bi Xuebo Zhao Daxing Xu Botao Ye Xuchang Yu Ziying Wang Danni Liu Yuanfeng Hao Fei Lu Zifeng Guo 《The Crop Journal》 SCIE CSCD 2024年第1期295-300,共6页
Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The e... Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions. 展开更多
关键词 Domestication selection Fertile spikelet number per spike(FSN) Geographical differentiation Grain number per spike(GNS) TaSus1
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解“毒”呕吐毒素 被引量:1
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作者 万福贤 张元红 +1 位作者 张丽丽 姜林 《大学化学》 CAS 2023年第7期157-163,共7页
呕吐毒素是镰刀菌群侵染谷物后产生的一种天然毒素,严重威胁粮食安全、食品安全和人类健康。本文借用拟人的手法,介绍了呕吐毒素的发现研究史、家族(单端孢霉烯族化合物)及典型成员、生物脱毒前沿研究,让读者以生动活泼的方式了解这种... 呕吐毒素是镰刀菌群侵染谷物后产生的一种天然毒素,严重威胁粮食安全、食品安全和人类健康。本文借用拟人的手法,介绍了呕吐毒素的发现研究史、家族(单端孢霉烯族化合物)及典型成员、生物脱毒前沿研究,让读者以生动活泼的方式了解这种危险的毒素,尤其是对高等农业和医学类院校的师生有很好的参考价值。 展开更多
关键词 呕吐毒素 镰刀菌 生物脱毒
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Baseline symptoms of depression and anxiety negatively impact the effectiveness of CBTi in treating acute insomnia among young adults 被引量:1
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作者 Chenxi zhang Shufei Zeng +6 位作者 Yan Xu Shuai Liu Shixu Du Leqin Fang Zhihong Lv lili zhang Bin zhang 《General Psychiatry》 CSCD 2023年第3期168-174,共7页
Background Cognitive-behavioural therapy for insomnia(CBTi)is the first-line treatment for those with this sleep disorder.However,depressive and anxiety symptoms often co-occur with acute insomnia,which may affect the... Background Cognitive-behavioural therapy for insomnia(CBTi)is the first-line treatment for those with this sleep disorder.However,depressive and anxiety symptoms often co-occur with acute insomnia,which may affect the effectiveness of CBTitreatment.Aims This study aimed to determine the impact of depressive and anxiety symptoms on the efficacy of CBTi in treating acute insomnia.Methods A single-arm clinical trial was conducted among individuals who have acute insomnia.Participants underwent self-guided CBTi for 1-week.Their insomnia,depressive symptoms and anxiety symptoms were evaluated using the Insomnia Severity Index and the Hospital Anxiety and Depression Scale at baseline,post-treatment and 3-month follow-up.Repeated measures analysis of variance was used to assess the effectiveness of CBTi in treating insomnia,depressive symptoms and anxiety symptoms.A multivariate Cox regression model was used to determine the impact of depressive and anxiety symptoms on insomnia.Results The study found significant reductions in insomnia,depressive symptoms and anxiety symptoms at both post-treatment and 3-month follow-up(F=17.45,p<0.001;F=36.37,p=0.001;and F=81.51,p<0.001,respectively).The duration of CBTi treatment had a positive impact on insomnia recovery(hazard ratio(HR)=0.94,p=0.018).However,baseline depressive symptoms(HR=1.83,p=0.004)and baseline anxiety symptoms(HR=1.99,p=0.001)had significant negative effects on insomnia recovery.Conclusions The study showed that a 1-week self-guided CBTi treatment is effective in treating acute insomnia and comorbid depressive and anxiety symptoms.However,baseline depressive and anxiety symptoms negatively impact treatment effectiveness.Therefore,clinicians should assess for depressive and anxiety symptoms before treating acute insomnia with monotherapy CBTi. 展开更多
关键词 IMPACT CBT treatment
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Supplemental Clostridium butyricum modulates lipid metabolism by reshaping the gut microbiota composition and bile acid profile in IUGR suckling piglets
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作者 Xin zhang Yang Yun +7 位作者 Zheng Lai Shuli Ji Ge Yu Zechen Xie Hao zhang Xiang Zhong Tian Wang lili zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期1150-1166,共17页
Background Intrauterine growth restriction(IUGR)can cause lipid disorders in infants and have long-term adverse effects on their growth and development.Clostridium butyricum(C.butyricum),a kind of emerging probiotics,... Background Intrauterine growth restriction(IUGR)can cause lipid disorders in infants and have long-term adverse effects on their growth and development.Clostridium butyricum(C.butyricum),a kind of emerging probiotics,has been reported to effectively attenuate lipid metabolism dysfunctions.Therefore,the objective of this study was to investigate the effects of C.butyricum supplementation on hepatic lipid disorders in IUGR suckling piglets.Methods Sixteen IUGR and eight normal birth weight(NBW)neonatal male piglets were used in this study.From d 3to d 24,in addition to drinking milk,the eight NBW piglets(NBW-CON group,n=8)and eight IUGR piglets(IUGR-CON group,n=8)were given 10 mL sterile saline once a day,while the remaining IUGR piglets(IUGR-CB group,n=8)were orally administered C.butyricum at a dose of 2×108colony-forming units(CFU)/kg body weight(suspended in 10 mL sterile saline)at the same frequency.Results The IUGR-CON piglets exhibited restricted growth,impaired hepatic morphology,disordered lipid metabolism,increased abundance of opportunistic pathogens and altered ileum and liver bile acid(BA)profiles.However,C.butyricum supplementation reshaped the gut microbiota of the IUGR-CB piglets,characterized by a decreased abundance of opportunistic pathogens in the ileum,including Streptococcus and Enterococcus.The decrease in these bile salt hydrolase(BSH)-producing microbes increased the content of conjugated BAs,which could be transported to the liver and function as signaling molecules to activate liver X receptorα(LXRα)and farnesoid X receptor(FXR).This activation effectively accelerated the synthesis and oxidation of fatty acids and down-regulated the total cholesterol level by decreasing the synthesis and promoting the efflux of cholesterol.As a result,the growth performance and morphological structure of the liver improved in the IUGR piglets.Conclusion These results indicate that C.butyricum supplementation in IUGR suckling piglets could decrease the abundance of BSH-producing microbes(Streptococcus and Enterococcus).This decrease altered the ileum and liver BA profiles and consequently activated the expression of hepatic LXRαand FXR.The activation of these two signaling molecules could effectively normalize the lipid metabolism and improve the growth performance of IUGR suckling piglets. 展开更多
关键词 Bile acid Clostridium butyricum Gut microbiota Intrauterine growth restriction Lipid metabolism Suckling piglet
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光催化酰基自由基与缺电子1,3-二烯的选择性1,6-加成反应实现羧酸的脱氧烯丙基化
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作者 张丽丽 李雨杭 +5 位作者 郭镇宇 李艳涛 李埝 李伟鹏 朱成建 谢劲 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第7期215-221,共7页
缺电子1,3-二烯类化合物在有机合成和材料科学领域具有重要应用.由于共轭效应的影响,该类化合物的化学转化不同于普通烯烃.一方面,1,3-二烯有多个反应位点,可以合成结构多样化的有机化合物,但另一方面,多反应位点的存在会使其面临1,4-/1... 缺电子1,3-二烯类化合物在有机合成和材料科学领域具有重要应用.由于共轭效应的影响,该类化合物的化学转化不同于普通烯烃.一方面,1,3-二烯有多个反应位点,可以合成结构多样化的有机化合物,但另一方面,多反应位点的存在会使其面临1,4-/1,6-区域选择性和Z/E立体选择性的难题.由于电子效应通过共轭π体系的传导差异,使得羰基1,3-二烯的δ位反应活性比β位低,因此1,6-加成反应较难发生.虽然过渡金属催化和有机催化方法的开发在一定程度上解决了1,6-加成选择性的问题,但使用温和的、易得的亲核体实现1,3-二烯的1,6-加成仍是一个难题.近年来,可见光驱动的光氧化还原催化提供了温和的自由基生成条件.一系列自由基前体被应用于不饱和羰基化合物的1,4-加成反应.然而,亲核碳自由基在1,6-加成反应中的应用非常少见,这是因为反应过程中生成的烯丙基自由基中间体容易进一步与二烯反应,发生聚合竞争反应.酰基自由基在有机转化中发挥了重要作用,基于前期本课题组在此方面的工作进展,本文利用可见光与有机膦的协同作用生成酰基自由基,通过酰基自由基对羰基1,3-二烯的1,6-共轭加成反应,实现了芳香羧酸的烯丙基化.经过对膦试剂、碱和反应溶剂等反应条件的筛选和优化,以86%的收率得到目标产物.随后,在此温和条件下对反应适用性进行考察,该反应对各种吸电子和给电子的邻、间、对位取代的芳香羧酸都具有很好的兼容性,各种官能团取代的(杂)芳香羧酸和环烯基甲酸与不同类型的羰基1,3-二烯均能顺利反应,以高达96%的收率高选择性地获得了一系列E构型的不饱和1,6-二羰基化合物.对于环酮缺电子二烯,利用该策略能够高选择性地合成共轭环烯酮.另外,将反应规模扩大至5 mmol时,反应收率几乎不受影响,成功实现了克级制备.自由基捕获实验表明酰基自由基参与了该反应.循环伏安法实验表明三(4-甲氧基苯基)膦能够很容易被失电子的光催化剂氧化,形成三芳基膦阳离子自由基,从而诱导羧酸脱氧.Stern-Volmer猝灭实验验证了激发态的光催化剂与羰基1,3-二烯的单电子转移过程,羰基1,3-二烯被还原为自由基阴离子中间体.酰基自由基能够迅速与其偶联生成阴离子中间体,随后经过质子化和异构化得到目标产物.综上,本文丰富了可见光催化芳香羧酸的脱氧官能团化反应类型,并为羰基1,3-二烯的转化提供了新的策略,为1,6-二羰基化合物的高效合成提供了一种新方法. 展开更多
关键词 光氧化还原 酰基自由基 1 3-二烯 1 6-共轭加成 1 6-二羰基化合物
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The case-dependent lignin role in lignocellulose nanofibers preparation and functional application-A review
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作者 Xiya zhang lili zhang +1 位作者 Yimin Fan Zhiguo Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第6期1553-1566,共14页
Lignocellulose nanofibers(LCNFs) as a new material is attracting extensive attention. The pretreatment and mechanical fibrillation are the two main stages involved in the preparation of LCNFs, and lignin plays the imp... Lignocellulose nanofibers(LCNFs) as a new material is attracting extensive attention. The pretreatment and mechanical fibrillation are the two main stages involved in the preparation of LCNFs, and lignin plays the important role of these two stages. This review discussed the interaction between lignin and chemicals in the pretreatment stage, and discovered the general law of the effect of lignin in the mechanical fibrillation stage.Lignin exhibits both promotion and inhibition effects on mechanical fibrillation, and the mutual competition between the two effects ultimately affects the energy consumption, morphology and yield of LCNFs. Furthermore, the recent research progress related to the contributions of lignin on the functional application of LCNFs was summarized, aiming to provide profound guidance for the preparation and application of LCNFs. 展开更多
关键词 Lignocellulose nanofibers LIGNIN FIBRILLATION CELLULOSE PRETREATMENT
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CD71-mediated liposomal arsenic-nickel complex combined with all-trans retinoic acid for the efficacy of acute promyelocytic leukemia
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作者 Xiao Liu lili zhang +7 位作者 Yueying Yang Weiwei Yin Yunhu Liu Chunyi Luo Ruizhe zhang Zhiguo Long Yanyan Jiang Bing Wang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2023年第4期80-95,共16页
Clinically,arsenic trioxide(ATO)was applied to the treatment of acute promyelocytic leukemia(APL)as a reliable and effective frontline drug.However,the administration regimen of AsⅢwas limited due to its fast clearan... Clinically,arsenic trioxide(ATO)was applied to the treatment of acute promyelocytic leukemia(APL)as a reliable and effective frontline drug.However,the administration regimen of AsⅢwas limited due to its fast clearance,short therapeutic window and toxicity as well.Based on CD71 overexpressed on APL cells,in present study,a transferrin(Tf)-modified liposome(LP)was established firstly to encapsulate AsⅢin arsenic-nickel complex by nickel acetate gradient method.The AsⅢ-loaded liposomes(AsLP)exhibited the feature of acid-sensitive release in vitro.Tf-modified AsLP(Tf-AsLP)were specifically taken up by APL cells and the acidic intracellular environment triggered liposome to release AsⅢwhich stimulated reactive oxygen species level and caspase-3 activity.Tf-AsLP prolonged half-life of AsⅢin blood circulation,lowered systemic toxicity,and promoted apoptosis and induced cell differentiation at lesion site in vivo.Considering that ATO combined with RA is usually applied as the first choice in clinic for APL treatment to improve the therapeutic effect,accordingly,a Tf-modified RA liposome(Tf-RALP)was designed to reduce the severe side effects of free RA and assist Tf-AsLP for better efficacy.As expected,the tumor inhibition rate of Tf-AsLP was improved significantly with the combination of Tf-RALP on subcutaneous tumor model.Furthermore,APL orthotopic NOD/SCID mice model was established by 60CO irradiation and HL-60 cells intravenously injection.The effect of co-administration(Tf-AsLP+Tf-RALP)was also confirmed to conspicuous decrease the number of leukemia cells in the circulatory system and prolong the survival time of APL mice by promoting the APL cells’apoptosis and differentiation in peripheral blood and bone marrow.Collectively,Tf-modified acid-sensitive AsLP could greatly reduce the systemic toxicity of free drug.Moreover,Tf-AsLP combined with Tf-RALP could achieve better efficacy.Thus,transferrinmodified AsⅢliposome would be a novel clinical strategy to improve patient compliance,with promising translation prospects. 展开更多
关键词 TRANSFERRIN Arsenic trioxide Acute promyelocytic leukemia All-trans retinoic acid LIPOSOME
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Bulk preparation of free-standing single-iron-atom catalysts directly as the air electrodes for high-performance zinc-air batteries
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作者 Hong-Bo zhang Yu Meng +11 位作者 Hong Zhong lili zhang Shichao Ding Lingzhe Fang Tao Li Yi Mei Peng-Xiang Hou Chang Liu Scott P.Beckman Yuehe Lin Hui-Ming Cheng Jin-Cheng Li 《Carbon Energy》 SCIE CSCD 2023年第5期57-66,共10页
The keen interest in fuel cells and metal-air batteries stimulates a great deal of research on the development of a cost-efficient and high-performance catalyst as an alternative to traditional Pt to boost the sluggis... The keen interest in fuel cells and metal-air batteries stimulates a great deal of research on the development of a cost-efficient and high-performance catalyst as an alternative to traditional Pt to boost the sluggish oxygen reduction reaction(ORR)at the cathode.Herein,we report a facile and scalable strategy for the large-scale preparation of a free-standing and flexible porous atomically dispersed Fe-N-doped carbon microtube(FeSAC/PCMT)sponge.Benefiting from its unique structure that greatly facilitates the catalytic kinetics,mass transport,and electron transfer,our FeSAC/PCMT electrode exhibits excellent performance with an ORR potential of 0.942 V at^(-3) mA cm^(-2).When the FeSAC/PCMT sponge was directly used as an oxygen electrode for liquid-state and flexible solid-state zinc-air batteries,high peak power densities of 183.1 and 58.0 mW cm^(-2) were respectively achieved,better than its powdery counterpart and commercial Pt/C catalyst.Experimental and theoretical investigation results demonstrate that such ultrahigh ORR performance can be attributed to atomically dispersed Fe-N_(5) species in FeSAC/PCMT.This study presents a cost-effective and scalable strategy for the fabrication of highly efficient and flexible oxygen electrodes,provides a significant new insight into the catalytic mechanisms,and helps to realize significant advances in energy devices. 展开更多
关键词 atomic Fe-N_(5)species free-standing electrode large-scale preparation oxygen reduction reaction zinc-air battery
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A new transition metal diphosphideα-MoP_(2) synthesized by a high-temperature and high-pressure technique
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作者 刘晓磊 于振海 +9 位作者 李建福 徐真真 周春银 董朝辉 张丽丽 王霞 余娜 邹志强 王晓丽 郭艳峰 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期563-567,共5页
Monoclinicα-MoP_(2),with the OsGe2-type structure(space group C2/m,Z=4)and lattice parameters a=8.7248(11)Å,b=3.2322(4)Å,c=7.4724(9)Å,andβ=119.263°,was synthesized under a pressure of 4~GPa at a ... Monoclinicα-MoP_(2),with the OsGe2-type structure(space group C2/m,Z=4)and lattice parameters a=8.7248(11)Å,b=3.2322(4)Å,c=7.4724(9)Å,andβ=119.263°,was synthesized under a pressure of 4~GPa at a temperature between 1100℃and 1200℃.The structure ofα-MoP_(2) and its relationship to other transition metal diphosphides are discussed.Surprisingly,the ambient pressure phase orthorhombicβ-MoP_(2)(space group Cmc21)is denser in structure thanα-MoP_(2).Room-temperature high-pressure x-ray diffraction studies exclude the possibility of phase transition fromβ-MoP_(2) to α-MoP_(2),suggesting thatα-MoP_(2) is a stable phase at ambient conditions;this is also supported by the total energy and phonon calculations. 展开更多
关键词 high-pressure synthesis monoclinic MoP_(2) crystal structure
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Editorial for a special issue on:(Photo)electrochemical materials and devices
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作者 Maowen Xu Yuxin zhang lili zhang 《Nano Materials Science》 EI CAS CSCD 2023年第2期117-118,共2页
With the development of human society and the depletion of non-renewable energy sources,alternate energy resources are becoming an urgent demand.In recent years,energy storage and conversion devices have drawn wide at... With the development of human society and the depletion of non-renewable energy sources,alternate energy resources are becoming an urgent demand.In recent years,energy storage and conversion devices have drawn wide attention as a bridge between sustainable energy sources and daily life. 展开更多
关键词 BECOMING depletion URGENT
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“化学在抗击新冠肺炎疫情中扮演的重要角色”专题教学 被引量:10
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作者 万福贤 王日为 +5 位作者 于斌 张元红 李映 张丽丽 艾仕云 姜林 《大学化学》 CAS 2020年第12期110-117,共8页
结合当前新冠病毒肺炎疫情防控工作,挖掘并凝练化学消毒剂、临床治疗或试验的典型药物、医用防护用品的加工材料等教学素材,开展了"化学在抗击新冠肺炎疫情中扮演的重要角色"专题教学,实现了专题教学与思政教育有机融合。通... 结合当前新冠病毒肺炎疫情防控工作,挖掘并凝练化学消毒剂、临床治疗或试验的典型药物、医用防护用品的加工材料等教学素材,开展了"化学在抗击新冠肺炎疫情中扮演的重要角色"专题教学,实现了专题教学与思政教育有机融合。通过专题教学,使学生深刻领略到化学学科的魅力,激发学生学习化学的兴趣,充分调动学生的学习积极性和主动性,增强学生战胜困难的信心和勇气,培养学生的学科素养、职业素养和科学素养,激发学生热爱祖国、热爱人民、热爱中国共产党的思想情感。 展开更多
关键词 新型冠状病毒肺炎 化学 云课堂 专题教学 课程思政
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Study on the Effectiveness of the Application of Perineal Wound Model in Teaching Midwife Interns
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作者 Chunrong Yang lili zhang +1 位作者 Duomei Ren Meirong Tian 《Journal of Clinical and Nursing Research》 2023年第3期24-27,共4页
Objective:To discuss and analyze the effectiveness of the application of perineal wound model in teaching midwife interns.Methods:The research subjects in this study were 40 midwife interns who enrolled in our hospita... Objective:To discuss and analyze the effectiveness of the application of perineal wound model in teaching midwife interns.Methods:The research subjects in this study were 40 midwife interns who enrolled in our hospital from January 2020 to December 2022,which were divided into a control group(consisted of 20 interns,taught with the conventional method)and a research group(consisted of 20 participants,taught with the perineal wound model)using the random number table method.The outcomes of these two groups were compared.Results:The examination results of the research group were better than control group(P<0.05);the interns of the research group were more satisfied towards the teaching method compared to the control group(P<0.05).Conclusion:Applying the perineal wound model in teaching midwife interns could effectively improve their examination achievements and teaching satisfaction,which brings a significant clinical value. 展开更多
关键词 Midwife intern Perineum wound Examination results Teaching satisfaction
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信息化背景下农科基础化学实验课程改革与实践 被引量:2
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作者 张丽丽 徐静 +2 位作者 朱树华 万福贤 尚鹏鹏 《大学化学》 CAS 2022年第8期137-144,共8页
以山东农业大学基础化学实验国家一流课程为例,介绍农科化学实验课程体系优化情况,总结借助信息技术在课程资源、教学模式、考评机制等方面进行的改革,实现信息技术与实验教学深度融合,为新农科人才培养奠定坚实基础。
关键词 基础化学实验 信息技术 课程建设
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体裁对中级英语水平学习者句法复杂度及作文整体质量打分的影响 被引量:1
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作者 张丽丽 刘海涛 《Chinese Journal of Applied Linguistics》 2021年第4期451-469,589,共20页
本文尝试考察体裁对二语作文句法复杂度及整体质量打分可能产生的影响。作文数据收集自一次测试以及写作课程课后作业,共计300余个文本。每一位受试要求完成议论文和记叙文两项写作任务。研究结果发现,体裁对二语句法复杂度有显著影响,... 本文尝试考察体裁对二语作文句法复杂度及整体质量打分可能产生的影响。作文数据收集自一次测试以及写作课程课后作业,共计300余个文本。每一位受试要求完成议论文和记叙文两项写作任务。研究结果发现,体裁对二语句法复杂度有显著影响,限时写作任务受影响程度更明显。整体质量打分与句法复杂度各指标的关系与体裁和是否限时任务有关。回归分析发现,对于限时任务,从句密度可以作为中级水平学习者作文质量整体打分的预测指标。该指标能够解释限时作文任务分数差异的6%,仅限时议论文任务而言,更可解释其分数差异的10%。研究证明,体裁与二语作文整体打分有关。虽然句法复杂度能够预测议论文整体质量打分,却与记叙文整体质量打分无关。后者或与其它语言特征有关。本研究认为,句法复杂度对二语作文质量整体打分的影响因体裁而有所差异。 展开更多
关键词 体裁影响 句法复杂度 二语写作 整体打分 中级水平学习者
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慢性伤口综合护理模式应用于改善伤口相关性疼痛的临床研究 被引量:4
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作者 吴玲 范英华 +5 位作者 张莉莉 周芳 周少婧 应红 王芳 李剑 《护理学》 2015年第2期23-28,共6页
目的:评价慢性伤口综合护理模式的减痛促愈效果。方法:对伤口护理中心就诊的200例下肢静脉溃疡患者进行观察分析。2014年2月至2014年8月共100例为观察组,采用本研究制定的慢性伤口综合护理模式进行干预;2013年5月至2013年12月共100例为... 目的:评价慢性伤口综合护理模式的减痛促愈效果。方法:对伤口护理中心就诊的200例下肢静脉溃疡患者进行观察分析。2014年2月至2014年8月共100例为观察组,采用本研究制定的慢性伤口综合护理模式进行干预;2013年5月至2013年12月共100例为对照组,按照伤口护理常规实施护理。分别于就诊第0、4、6周观察两组患者疼痛评分及伤口愈合率。结果:两组患者疼痛评分及伤口愈合率差异有统计学意义。结论:慢性伤口综合护理模式的应用可有效改善下肢静脉溃疡患者疼痛,促进伤口愈合,以期能为临床相关医护人员的实践提供指导与借鉴。 展开更多
关键词 伤口相关性疼痛 综合护理模式 伤口护理
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铂基催化剂的氧还原反应路径调控
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作者 张利利 蒋苏毓 +1 位作者 马炜 周震 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第6期1433-1443,共11页
随着世界人口的不断增长及人类生活质量的提高,人类对能源的需求逐步增加.这将加快化石燃料的枯竭,并导致环境和气候问题日益严峻.各国政府积极部署能源策略改革,逐步减弱各行业对煤炭等化石燃料的依赖.2020年,中国政府宣布将实施更加... 随着世界人口的不断增长及人类生活质量的提高,人类对能源的需求逐步增加.这将加快化石燃料的枯竭,并导致环境和气候问题日益严峻.各国政府积极部署能源策略改革,逐步减弱各行业对煤炭等化石燃料的依赖.2020年,中国政府宣布将实施更加有效的政策和措施,并于2030年和2060年分别实现“碳达峰”和“碳中和”目标.开发金属-空气电池、质子交换膜燃料电池以及绿色电化学合成等储能与转换技术,是解决环境问题、保证清洁能源被高效可持续利用的重要手段之一.如何提高装置的储能与转换效率是商业化应用面临的挑战之一,而加快电极反应的动力学过程是解决这问题的根源.氧还原反应(ORR)作为可充电电池、原电池、电解池装置中的重要反应,其缓慢的动力学过程,限制了电池的能量密度和电合成效率.开发高效稳定的电催化剂可以应对这一挑战.然而,商用Pt/C催化剂却面临着储量有限、价格高、性能不能达到实际应用需求的问题;非Pt催化剂发展迅速,但其替代Pt基催化剂仍面临诸多问题和挑战.因此,更多的研究应聚焦于解决Pt基催化剂的瓶颈问题.近年来,关于提高低Pt催化剂的ORR性能研究取得了一定进展,分别采用不同的策略促进以H_(2)O为产物的4e-ORR和以H_(2)O_(2)为产物的2e-ORR.本文从吸附能和空间结构角度,系统总结和讨论了优化Pt基催化剂4e-ORR/2e-ORR性能的调控策略,明确了ORR活性和选择性的关系及其调控策略.具体而言,含氧物种在Pt位点上的吸附强度对ORR的动力学过程(活性)起关键作用,而O‒O键的解离/保留对ORR路径(选择性)有决定性影响;暴露更多活性位或提高单个活性位点的催化能力的相关策略所引起的配体效应、电子效应、应力效应等赋予Pt位点一定的功能性质,选择性催化氧还原以4e或2e转移途径进行.最后,归纳了Pt基催化剂在催化ORR的应用研究中存在的问题和面临的挑战,并对未来的研究发展提出了展望. 展开更多
关键词 氧还原反应 电催化剂 选择性 过氧化氢
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可持续释放银离子和活性氧的ZnO/Ag/rGO三元新型光催化抗菌剂(英文) 被引量:10
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作者 吴赟炎 张莉莉 +4 位作者 周亚洲 李毅 刘芹芹 胡娟 杨娟 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第5期691-702,共12页
由于具有独特的物理与化学性质,银纳米粒子被广泛应用于传感器、电化学、光催化等多个领域.在生物领域,银纳米粒子可以通过释放银离子有效地解决细菌感染问题,但是其本身的毒性不可忽略.为了减小银纳米粒子的潜在毒性,迫切需要寻找一种... 由于具有独特的物理与化学性质,银纳米粒子被广泛应用于传感器、电化学、光催化等多个领域.在生物领域,银纳米粒子可以通过释放银离子有效地解决细菌感染问题,但是其本身的毒性不可忽略.为了减小银纳米粒子的潜在毒性,迫切需要寻找一种可持续释放银离子(Ag^+)的新型复合光催化抗菌剂.已有研究报道可将银纳米粒子负载在氧化铝、凝胶和二氧化硅上形成银基抗菌材料,但是大多数材料中银纳米颗粒尺寸较大,分布不均匀,且仅靠快速释放的银离子进行抗菌.本文通过一步溶剂热法制备了ZnO/Ag/rGO三元光催化抗菌剂,其中分别由银纳米粒子和氧化锌(ZnO)形成的银离子和活性氧(ROS)可对大肠杆菌和金黄色葡萄球菌产生协同抗菌作用.负载在还原氧化石墨烯(rGO)上的银纳米粒子持续释放出微量的银离子,后者通过库仑引力牢固地吸附在带负电荷的细菌细胞膜上,从而干扰细菌DNA合成,进而使细菌丧失分裂繁殖能力;与还原氧化石墨烯和银纳米粒子复合的氧化锌可以产生更多的O_2^(·–)和·OH等自由基,具有氧化能力的自由基可分解细菌细胞膜使细菌破裂死亡.银纳米粒子的表面等离子体共振效应不仅可以拓宽氧化锌半导体材料的光吸收范围,而且可以作为电子捕获阱捕获电子,加速光生电子与空穴的分离,有效抑制光生载流子的复合.与其他银基抗菌材料相比,该材料可以实现了30天低浓度银离子持续释放,并利用产生的活性氧和银离子稳定高效地进行抗菌.采用XRD,XPS,SEM,TEM,HRTEM,PL和ESR等表征方法分析了材料的结构、形貌、化学组成、元素价态及光学性质,并通过抑菌圈、最低抑菌浓度(MIC)和最低杀菌浓度(MBC)等性能测试比较了材料的抗菌性能.XRD和XPS结果证明银和氧化锌纳米粒子成功地负载在还原氧化石墨烯上.SEM,TEM和HRTEM分析发现还原氧化石墨烯上的银和氧化锌纳米粒子分布均匀,尺寸较小(5–10 nm).PL和ESR表征表明ZnO/Ag/rGO相比于ZnO/rGO和Ag/rGO有更好的载流子分离和自由基产生能力.因此,ZnO/Ag/rGO材料对大肠杆菌和金黄色葡萄球菌具有更低的最低抑菌浓度(MIC_(E.coli)=100×10^(-6)μg/mL,MIC_(S.aureus)=80×10^(-6)μg/mL)和最低杀菌浓度,该材料在抗菌领域具有潜在的应用前景. 展开更多
关键词 氧化锌 银纳米粒子 还原氧化石墨烯 银离子持续释放 协同抗菌机制 活性氧
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蛋白质组学研究方法在蚕丝学中的应用
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作者 代君君 舒蕊 +4 位作者 刘健 章玉萍 陈明 张丽丽 范涛 《农业科学》 2017年第9期686-692,共7页
家蚕既是具有重要经济价值的绢丝昆虫,又是现代生命科学研究的模式生物。近年来,随着蛋白质组学研究技术的飞速发展,有关家蚕性腺、丝腺、血液、中肠、触角等重要组织器官蛋白质组学的研究取得了很大进展,为揭示家蚕重要性状的形成机制... 家蚕既是具有重要经济价值的绢丝昆虫,又是现代生命科学研究的模式生物。近年来,随着蛋白质组学研究技术的飞速发展,有关家蚕性腺、丝腺、血液、中肠、触角等重要组织器官蛋白质组学的研究取得了很大进展,为揭示家蚕重要性状的形成机制、生殖发育调控、组织器官功能、天然免疫等方面提供了丰富的信息。文章对此作了简要的综述,并结合基因组学、生物信息学的研究技术,讨论了家蚕蛋白质组学今后的发展趋势及其应用前景。 展开更多
关键词 家蚕 蛋白质组 研究方法 进展 应用
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前驱体改性法制备薄层多孔富氨基的石墨相氮化碳用于光催化降解RhB和光催化制氢 被引量:2
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作者 黄婷 陈佳琪 +8 位作者 张莉莉 Alireza Khataee 韩巧凤 刘孝恒 孙敬文 朱俊武 潘书刚 汪信 付永胜 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第2期497-506,共10页
半导体光催化是一种利用半导体将太阳能转换为高能化学能的绿色技术,在可再生清洁能源生产和污染物修复领域有着巨大的应用前景.石墨相氮化碳(g-C_(3)N_(4))作为一种环境友好的非金属半导体,因其制备工艺简单、来源丰富、热稳定性和化... 半导体光催化是一种利用半导体将太阳能转换为高能化学能的绿色技术,在可再生清洁能源生产和污染物修复领域有着巨大的应用前景.石墨相氮化碳(g-C_(3)N_(4))作为一种环境友好的非金属半导体,因其制备工艺简单、来源丰富、热稳定性和化学稳定性好、可见光吸收范围及特殊的电子性能而受到广泛关注.但一般常用氮源前驱体如二氰二胺、三聚氰胺等所制备的块状石墨相氮化碳存在团聚、比表面积小和光生载流子分离效率低等问题,严重抑制了其光催化活性.本文采用前驱体改性法制得具有高效光催化活性的石墨相氮化碳.利用氰基在酸性条件下易水解这一特性,通过调节不同种类和浓度的酸(硝酸、盐酸、磷酸等)改性二氰二胺,制得一系列新前驱体,通过焙烧制备石墨相氮化碳.采用X射线粉末衍射、X射线光电子能谱、傅立叶变换红外光谱、透射电子显微镜和场发射扫描电子显微镜等表征手段对前驱体及氮化碳的结构及微观形貌进行研究.结果表明,通过浓硝酸改性二氰二胺成功制得脒基脲硝酸盐,其煅烧后所得的HNO_(3)-CN(5H-CN)催化剂具有较好的薄层多孔结构,且面内三均三嗪环末端具有丰富的氨基官能团.TG-FTIR结果表明,5H-CN通过不同于传统氮化碳的热缩合过程,导致了其多孔富氨基的结构.光催化性能测试表明,5H-CN对光催化降解罗丹明B(Rh B)具有最佳的催化活性,其准一级速率常数达0.05316 min^(-1),是普通块状石墨相氮化碳(CN)的34倍.此外,5H-CN的光催化制氢性能也远远高于CN.通过紫外-可见漫反射光谱、莫特-肖特基曲线和瞬态光电流测试等方法研究催化剂的形貌结构对光催化活性的影响.结果表明,5H-CN催化剂具有较高的光催化活性主要归因于其薄层多孔结构提供了更大的比表面积(148.76 m^(2)g^(-1)),表面有更多的活性位点,同时有助于光生载流子的有效分离;其面内三均三嗪环的末端边缘丰富的氨基结构使得其能带结构发生变化,更负的导带位置使其光生电子的还原能力更强,从而有利于光催化反应的进行.其光催化机理归纳如下:在5H-CN催化剂光催化降解Rh B过程中,O_(2)·^(-)作为最主要的活性物种可与空穴(h+)同时氧化催化剂表面的Rh B分子,从而达到光催化降解Rh B的作用;在5H-CN催化剂光催化制氢过程中,铂(3wt%Pt)作为助催化剂可以负导带上的光生电子(e-)快速迁移,迁移的e-可以直接还原水中的氢质子生成氢气. 展开更多
关键词 前驱体改性法 石墨相氮化碳 光催化降解 光催化制氢 富氨基结构
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