检索结果-南通市图书馆

Chemical Research in Chinese Universities 2008年第5期24卷 546-549页

作者： fei yan-qun LUO Gui-min FENG Guo-dong CHEN Huan-wen fei Qiang HUAN yan-fu JIN Qin-han Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education Institute of Analytical Science School of Chemistry Jilin Province Research Center for Engineering and Technology of Spectral Analytical Instruments Jilin University Changchun 130021 P R. China

This article focuses on iodine determination by microwave plasma torch atomic emission spectrometry （MPT-AES） coupled with online preconcentration vapor generation method. A new desolvation device, multistrand Nafion dryer, was used as the substitute for condenser desolvation system. Some experimental conditions, such as preconcentration time, acidity of sample solution, rinsing solution acidity and dynamic linear range were investigated and optimized. The new desolvation system eliminates the problem of decreasing emission intensity of I（I） 206.238 nm line with the increase of working time on a conventional condenser desolvation system, thus greatly improving the reproducibility.

关键词： MPT-AES On-line preconcentration Vapor generation Nation dryer Membrane desolvation

XIAP as a prognostic marker of early recurrence of nonmuscular invasive bladder cancer

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Chinese Medical Journal 2007年第6期120卷 469-473页

作者： LI Ming SONG Tao YIN Zhen-fei NA yan-qun Department of Urology Peking University First Hospital Beijing 100034 China

Background Dysregulation of apoptosis has been implicated not only in carcinogenesis and tumor progression but also in tumor recurrence. We investigated whether the expression of X-linked inhibitor of apoptosis （XIAP） might predict early recurrence in patients with non-muscular invasive bladder cancer. Methods The cohort comprised 176 consecutive patients with primary superficial bladder cancer treated with transurethral resection. Immunohistochemical staining using the standard avidin-bioUn-peroxidase technique and RT-PCR were used to detect XIAP protein and mRNA expressions in cancer tissues. The relationship between XIAP expression and clinicopathological characteristics, cancer recurrence were analyzed. Results XIAP expression was observed in 108 cases （61.4%） and no expression in 68. There was no correlation between XIAP expression rate and the tumor pathological grade, but was an apparent trend toward the increased XIAP levels from well （G1） to poor （G3） differentiated cancer. Eighty-two （46.6%） patients experienced tumor recurrence at a mean of 28.6 months of the follow-up; 66 of them expressed XIAP （61.1%） and 16 were XIAP negative （23.5%）. Twelve patients presented with invasive disease at the time of relapse and all of them expressed XIAP. Patients without XIAP expression or with low tumor grades had significantly higher recurrence-free survival than those with XIAP expression （log rank test ,P=-0.0015） or high tumor grades （log rank test P〈0.001）. Multivariate analysis revealed that XIAP expression, tumor grade, and tumor number were independent predictors for the recurrence of non-muscular invasive bladder cancer （P=-0.004, 0.016, and 0.043, respectively）. Conclusions XIAP may be considered as a new independent prognostic marker for early recurrence of non-muscular invasive bladder cancer.

关键词： XIAP urinary bladder neoplasms recurrence

聚苯胺/聚吡咯-纳米二氧化硅复合薄膜的合成及防腐性能

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高等学校化学学报 2016年第11期37卷 2025-2033页

作者：李传宪石恩华杨爽姚博杨飞燕群中国石油大学(华东)储运与建筑工程学院山东省油气储运安全省级重点实验室青岛266580

采用循环伏安法(CV)在316不锈钢(316SS)表面聚合生成聚苯胺/聚吡咯-纳米二氧化硅(PAni/PPySiO_2)共聚复合薄膜.通过电化学工作站、傅里叶变换红外光谱仪(FTIR)、X射线光电子能谱仪(XPS)和扫描电子显微镜(SEM)等考察了聚苯胺(PAni)、聚苯... 详细信息

采用循环伏安法(CV)在316不锈钢(316SS)表面聚合生成聚苯胺/聚吡咯-纳米二氧化硅(PAni/PPySiO_2)共聚复合薄膜.通过电化学工作站、傅里叶变换红外光谱仪(FTIR)、X射线光电子能谱仪(XPS)和扫描电子显微镜(SEM)等考察了聚苯胺(PAni)、聚苯胺/聚吡咯(PAni/PPy)与PAni/PPy-SiO_2薄膜的电化学聚合过程、分子结构和特征形貌;在3.5%(质量分数)Na Cl水溶液中利用Tafel极化曲线和电化学阻抗谱(EIS)分别考察了PAni,PAni/PPy与PAni/PPy-SiO_2薄膜对不锈钢的防腐性能.结果表明,通过电化学法可以在316不锈钢表面生成PAni/PPy-SiO_2共聚复合薄膜;相对于PAni薄膜与PAni/PPy薄膜,PAni/PPy-SiO_2薄膜有着更密实的表面结构,其对不锈钢的保护能力优于PAni/PPy薄膜和PAni薄膜,纳米SiO_2的掺杂通过加强膜层的机械屏蔽作用并抑制腐蚀反应过程中电荷的传递,提高了薄膜的防腐能力.

关键词：聚苯胺聚吡咯二氧化硅复合薄膜防腐性能

双重对象同时检测的新型荧光纳米粒子传感器的制备

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高等学校化学学报 2008年第1期29卷 83-85页

作者：费砚群罗贵民冯国栋费强陈焕文梁学凯赵晓君郇延富吉林大学分子酶学工程教育部重点实验室长春130021 吉林大学化学学院长春130012 北达科他大学化学系大福克斯58203

New fluorescent silica nanoparticles for sensors simultaneous determination of double targets were synthesized via a reverse microemulsion method based on the fluorescence resonance energy transfer(FRET).Nanoparticle A was doped with a dye complex which consisted of two dye molecules,fluorescein and *** dye molecules were first linked with avidin and biotin,*** then formed a stable dye complex through avidin-biotin bridge within the distance of *** B was doped with fluorescein *** a result of this combination,the nanoparticles emit double wavelengths when a single excitation wavelength is *** results show that the fluorescent nanoparticles are promising fluorescent labeling reagents for the sensitive detection of double targets.

关键词：纳米粒子双重对象同时检测荧光共振能量转移

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学分制下考试管理的特点、问题与对策

安庆师范学院学报（社会科学版） 2006年第4期25卷 109-111页

作者：费群燕安徽农业大学教务处安徽合肥230036

学分制下考试周期短、门类多;课程考核具有灵活性变通性。当前考试管理规范化程度低,考试管理机构和制度不够健全,考试模式单一,作弊现象屡禁不止。加强学分制考试管理:要转变考试管理思想和观念,树立学生主体性意识;加强制度建设,建立... 详细信息

学分制下考试周期短、门类多;课程考核具有灵活性变通性。当前考试管理规范化程度低,考试管理机构和制度不够健全,考试模式单一,作弊现象屡禁不止。加强学分制考试管理:要转变考试管理思想和观念,树立学生主体性意识;加强制度建设,建立健全考试管理机构;进行考试内容、方法的改革。

关键词：学分制考试管理问题对策

外源铅在土壤中的形态、分布及其对土壤养分的影响

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水土保持学报 2008年第1期22卷 74-77,82页

作者：朱江周俊费群燕兰京马荣艳安徽农业大学安徽合肥230036 安徽省亳州市谯城区农委安徽亳州236000

通过对加入外源铅的砂姜黑土、黄褐土、红壤进行培养处理,测定土壤中各形态铅及水溶态NH4+,K+和速效态磷的含量,研究外源铅在各类土壤中的形态分布特点及对土壤养分的影响。结果表明:交换态和残渣态的铅为红壤>黄褐土>砂姜黑土,碳酸盐... 详细信息

通过对加入外源铅的砂姜黑土、黄褐土、红壤进行培养处理,测定土壤中各形态铅及水溶态NH4+,K+和速效态磷的含量,研究外源铅在各类土壤中的形态分布特点及对土壤养分的影响。结果表明:交换态和残渣态的铅为红壤>黄褐土>砂姜黑土,碳酸盐态铅为砂姜黑土>黄褐土>红壤,铁锰氧化态铅为红壤>砂姜黑土>黄褐土,有机结合态铅为黄褐土>砂姜黑土>红壤;交换态和残渣态所占比例随着外源铅的浓度增大而提高,有机结合态的比例随着外源铅浓度增大降低,碳酸盐结合态铅在砂姜黑土、铁锰氧化态铅在红壤上则呈现外源铅小于500 m g/kg时比例增高,大于500 m g/kg时比例开始下降的状况;加入外源铅的土壤中,水溶态的NH4+和K+的浓度增大,使其流失的风险性增加;水溶态磷和铅离子生成难溶性磷酸铅盐被固结,使速效磷的浓度减少,降低了水溶性磷肥的功效。

关键词：外源铅土壤形态与分布交换与固结

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典型背景区大气颗粒物中元素粒径分布特征

环境科学与技术 2017年第6期40卷 133-140页

作者：王申博余飞燕启社王群姜楠尹沙沙张瑞芹郑州大学化学与分子工程学院河南郑州450001

为探究背景区域大气颗粒物中金属元素污染特征,该研究利用四级颗粒物撞击式采样器(<1μm、1~2.5μm、2.5~10μm和10~18μm)于2014年冬季在郑州市中牟县郊区采集颗粒物样品。使用电感耦合等离子体质谱仪(ICP-MS)分析23种元素的浓度,并利... 详细信息

为探究背景区域大气颗粒物中金属元素污染特征,该研究利用四级颗粒物撞击式采样器(<1μm、1~2.5μm、2.5~10μm和10~18μm)于2014年冬季在郑州市中牟县郊区采集颗粒物样品。使用电感耦合等离子体质谱仪(ICP-MS)分析23种元素的浓度,并利用富集因子法(EF)和主成分分析法(PCA)解析颗粒物中元素来源。结果表明,该区域金属元素浓度高于上海和北京,且不同元素粒径分布具有差异性。金属Se、Cd、Ag、Sb、Pb、Sn、Zn、Cr、Cu和As受明显的人为源影响,Ca、Sr、Ba、Be、Mn、Mg、K、V、Fe、Al和Ti主要来自自然源。该区域大气中元素的主要来源有地壳源、燃煤源、机动车排放源、冶金化工排放源、垃圾焚烧排放源和建筑扬尘排放源。此研究成果可以为政府制定污染防治方案提供科学依据。

关键词：金属元素粒径分布典型背景区主成分分析源解析

Activation of adult endogenous neurogenesis by a hyaluronic acid collagen gel containing basic fibroblast growth factor promotes remodeling and functional recovery of the injured cerebral cortex

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Neural Regeneration Research 2025年第10期20卷 2923-2937页

作者： yan Li Peng Hao Hongmei Duan fei Hao Wen Zhao Yudan Gao Zhaoyang yang Kwok-Fai So Xiaoguang Li Department of Neurobiology School of Basic Medical SciencesCapital Medical UniversityBeijingChina China Rehabilitation Science Institute China Rehabilitation Research CenterBeijing Key Laboratory of Neural Injury and RehabilitationBeijingChina Center of Neural Injury and Repair Beijing Institute for Brain DisordersBeijingChina Beijing Key Laboratory for Biomaterials and Neural Regeneration School of Engineering MedicineBeihang UniversityBeijingChina Guangdong-HongKong-Macao Institute of CNS Regeneration Ministry of Education CNS Regeneration Collaborative Joint LaboratoryJinan UniversityGuangzhouGuangdong ProvinceChina Bioland Laboratory(Guangzhou Regenerative Medicine and Health Guangdong Laboratory) GuangzhouGuangdong ProvinceChina Department of Ophthalmology and State Key Laboratory of Brain and Cognitive Sciences The University of Hong KongHong Kong Special Administration RegionChina Center for Brain Science and Brain-Inspired Intelligence Guangdong-HongKong-Macao Greater Bay AreaGuangzhouGuangdong ProvinceChina Co-innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Biomedical Engineering School of Biological Science and Medical EngineeringBeihang UniversityBeijingChina

The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after ***,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains *** this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic *** findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated ***,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain *** findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.

关键词： adult endogenous neurogenesis basic fibroblast growth factor-hyaluronic acid collagen gel cortical remodeling functional recovery migration motor cortex injury neural circuits neural stem cells newborn neurons proliferation

miRNA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

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Neural Regeneration Research 2025年第1期20卷 277-290页

作者： Meng Cong Jing-Jing Hu yan Yu Xiao-Li Li Xiao-Ting Sun Li-Ting Wang Xia Wu Ling-Jie Zhu Xiao-Jia yang Qian-Ru He fei Ding Hai-yan Shi School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education and Coinnovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Physiology Jiangsu Health Vocational CollegeNanjingJiangsu ProvinceChina Department of Pathology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve ***-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular ***,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain *** investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose *** mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest *** performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest ***,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded ***,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously *** findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in ***-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell *** helps to explain the mechanism of action of the secretome and e

关键词： axotomy cell-free therapy conditioned medium extracellular vesicles hypoxic preconditioning microRNA oxygen-glucose deprivation peripheral nerve injury Schwann cell precursors

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基于耦合界面键合效应的石墨烯磨损研究

原子与分子物理学报 2025年第6期42卷 66-75页

作者：郑云飞卢艳武汉科技大学冶金装备及其控制教育部重点实验室武汉430081 武汉科技大学机械传动与制造工程湖北省重点实验室武汉430081 武汉科技大学精密制造研究院武汉430081

石墨烯作为二维固体润滑材料,其超滑特性不仅是物理作用结果,其化学键结构机制下的摩擦化学现象,是深入理解石墨烯摩擦性能的关键.本文采用分子动力学(MD)方法构建了多重层数石墨烯增强不同粗糙形貌的金属基底模型,实现了其与金刚石尖... 详细信息

石墨烯作为二维固体润滑材料,其超滑特性不仅是物理作用结果,其化学键结构机制下的摩擦化学现象,是深入理解石墨烯摩擦性能的关键.本文采用分子动力学(MD)方法构建了多重层数石墨烯增强不同粗糙形貌的金属基底模型,实现了其与金刚石尖端滑动过程的动态分析,揭示了考虑尖端与石墨烯之间存在界面键时石墨烯层的理化耦合作用下的磨损机理.研究结果表明:当考虑金刚石尖端与石墨烯之间化学键合时,石墨烯发生磨损破裂的临界载荷相对于不考虑界面化学键时的值减小,这是由于界面键的形成会剥离石墨烯导致石墨烯断裂所致;金属基底的粗糙度也是决定石墨烯发生磨损破裂时临界载荷的重要因素之一,当粗糙度增大,临界载荷减小,同时通过增加石墨烯层的层数(增韧)来提高石墨烯发生磨损破裂失效的临界载荷.

关键词：石墨烯层界面键分子动力学磨损破裂

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