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Fluorescence Enhancement of Polyamine Derivatives of 1,8-Naphthalimide with Transition Metal Ions
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作者 文国涛 朱满洲 +3 位作者 王卓 孟祥明 胡惠媛 郭庆祥 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第6期506-510,共5页
A series of fluorescent chemosensors 1-3 were synthesized to detect transition metal ions. At the room temperature, fluorescence intensities of these chemosensors in acetonitrile without transition metal ions were fou... A series of fluorescent chemosensors 1-3 were synthesized to detect transition metal ions. At the room temperature, fluorescence intensities of these chemosensors in acetonitrile without transition metal ions were found to be very weak, due to the process of the efficient intramolecular photoinduced electron transfer (PET). However, after addition of the transition metal ions, the chemoscnsor 1-3 exhibits obvious fluorescence enhancement. Moreover, the intensity of the fluorescence emission of chemosensors increases significantly in the presence of Zn^2+ and Cd^2+. The fluorescent chemosensors with different polyamine as receptors show diverse affinity abilities to the transition metal ions and signal the receptor-metal ion interaction by the intensity change of fluorescence emission. 展开更多
关键词 Transition metal ion 1 8-naphthalimide Photoinduced electron transfer Fluorescence enhancement Fluorescent chemosensor
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Fluorescent and thermal properties of siloxane-polyurethanes based on 1,8-naphthalimide 被引量:9
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作者 Yan Ma Qian-Yun Tang +2 位作者 Ji Zhu Li-Hong Wang Cheng Yao 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第5期680-686,共7页
A series of fluorescent siloxane-polyurethanes(HPMS-PUs) containing an amino-functionalized,1 8-naphthalimide,fluorescent monomer(AABD) as a chain extender were synthesized.The properties of the HPMS-PUs were inve... A series of fluorescent siloxane-polyurethanes(HPMS-PUs) containing an amino-functionalized,1 8-naphthalimide,fluorescent monomer(AABD) as a chain extender were synthesized.The properties of the HPMS-PUs were investigated by UV–vis and fluorescence spectroscopies,thermogravimetric analysis and thermal migration behavior.The maximum absorption and emission wavelengths of HPMS-PUs showed a red shift of about 4 nm and a blue shift of about 9 nm,respectively,compared to those of AABD.The Stokes shifts of AABD and HPMS-PU2 were 3514 and 2931 cm 1,respectively.The quantum yield of HPMS-PU2 was 0.79,which was six times higher than that of AABD.Concentration self-quenching was observed in both AABD and HPMS-PUs.The fluorescence of HPMS-PUs was quite stable with respect to both temperature and fluorescence quencher effects.The thermal stability of HPMS-PUs increased with AABD content.The fluorophore units in the HPMS-PUs did not readily migrate. 展开更多
关键词 Polysiloxane Polyurethane 1 8-naphthalimide Fluorescence Thermal properties
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New trends of molecular probes based on the fluorophore4-amino-1,8-naphthalimide 被引量:1
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作者 Lin Zhou Lijuan Xie +1 位作者 Chuanhao Liu Yi Xiao 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第10期1799-1808,共10页
4-Amino-1,8-naphthalimide(ANI) represents a valuable fluorophore from which a large number of probes have been derived in order to meet the requirements from the fields of biological sensing and imaging. In this revie... 4-Amino-1,8-naphthalimide(ANI) represents a valuable fluorophore from which a large number of probes have been derived in order to meet the requirements from the fields of biological sensing and imaging. In this review, the major progresses of ANI-based fluorescent probes in the past decade have been highlighted and categorized into three trends. The future development of ANI probes is also expected. This review provides a great deal of references and illuminating comments which will be helpful for the researchers designing and using fluorescent probes. 展开更多
关键词 4-Amino-1 8-naphthalimide TWO-PHOTON SUBCELLULAR ORGANELLE ENZYME Hybrid
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Theoretical Study on the Electronic Structures and Spectral Properties of 1,8-Naphthalimide Derivatives
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作者 王艳 高慧 +2 位作者 杨平 聂光华 宋新建 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第6期813-820,共8页
The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(1),4-... The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(1),4-(2-tert-butylphenoxy)-N-(2-hydroxyethyl)-1,8-naphthalimide(2), and 4-[2,4-di(tert-butyl)]phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(3), are investigated by density functional theory(DFT) and time-dependent density functional theory(TD-DFT) calculations in conjunction with polarizable continuum models(PCMs). Four functionals and ten basis sets are employed for 1 to calculate the electron transition energies, which were compared with the experimental observations. Our results reveal that the B3LYP/6-311+G(d,p) method is the best choice to reproduce the experimental spectra. Moreover, the effects of substituents on the molecular geometries, electronic structures, absorption and emission spectra are also studied at the B3LYP/6-311+G(d,p) level. We find that the gap between the highest occupied molecular orbital(HOMO) and the lowest unoccupied molecular orbital(LUMO) decreases with increasing the number of tert-butyl substituents onto the phenoxy groups, suggesting red-shift of the absorption and emission bands. This is related to the increase of conjugation from 1 to 2 and 3. Our calculations are in good agreement with the experimental results. 展开更多
关键词 1 8-naphthalimide derivatives density functional theory frontier molecular orbital absorption spectrum emission spectrum
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A Novel Naked-Eye and Dual-Channel Responsive Fluorescent Probe for Cu2+ Based on 3,4-Disubstituted-1,8-naphthalimide
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作者 李辉 郝志云 +1 位作者 盂欣 朱以常 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期235-239,I0002,共6页
A new 3,4-disubstituted-l,8-naphthalimide derivative H1 was designed and synthesized as a selective fluorescent probe for Cu2+ over miscellaneous metM ions in aqueous media. Upon mixing with Cup-+ in CH3OH:H2O (1... A new 3,4-disubstituted-l,8-naphthalimide derivative H1 was designed and synthesized as a selective fluorescent probe for Cu2+ over miscellaneous metM ions in aqueous media. Upon mixing with Cup-+ in CH3OH:H2O (1:1, volume ratio), the increase of fluorescence intensity and a bathochromic shift of absorbance of H1 could be observed with a notable color response (changing from yellow to pink), htrthermore, Cu2+ coordinates to the probe H1 and a 1:1 metal-ligand complex was formed. 展开更多
关键词 1 8-naphthalimide Copper(II) FLUORESCENCE
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The remarkable effect of amino hydrogen on membrane permeability and organelle staining of 1,8-naphthalimide dyes
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作者 Zhifeng Li Qinglong Qiao +6 位作者 Ning Xu Kai An Wenchao Jiang Yi Tao Pengjun Bao Yinchan Zhang Zhaochao Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第2期347-351,共5页
Membrane permeability and intracellular diffusion of fluorescent probes determine staining selectivity of intracellular substructures.However,the relationship between the molecular structure of fluorescent probes and ... Membrane permeability and intracellular diffusion of fluorescent probes determine staining selectivity of intracellular substructures.However,the relationship between the molecular structure of fluorescent probes and their membrane permeability and intracellular distribution is poorly understood.In this paper,we reported a series of 1,8-naphthalimide dyes and carried out cell imaging experiments,and found that the presence of amino hydrogen in these dyes played a crucial role in their cell membrane permeability and intracellular distribution.The secondary amino group containing compounds 1-4 show excellent membrane permeability and strong fluorescence in living cells.While the tertiary amine containing dyes 5 and 6 can hardly permeate the cell membrane though they show extremely similar structure with compounds 2-4.Compound 1 can selectively image lipid droplets by selecting the wavelength of excitation light.With the specificity for lysosomes,2 and 4 have been used in long-term time-lapses imaging of lysosomal dynamics and tracking the process of lysosome-lysosome interaction,fusion and movement.The effect of hydrogen-containing amino substituent on the cell membrane permeability of fluorescent molecules is promising for the development of better biocompatible probes. 展开更多
关键词 Amino hydrogen 1 8-naphthalimide Cell permeability Lipid droplet LYSOSOME
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Design of a 1,8-naphthalimide-based OFF-ON type bioorthogonal reagent for fluorescent imaging in live cells
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作者 Zhuzhou Shao Chun Zhang +6 位作者 Xiaohua Zhu Yajun Wang Wenyuan Xu Yu Chen Xiaoming Wang Hailiang Zhu Yong Liang 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第12期2169-2172,共4页
A novel 1,8-naphthalimide-based OFF-ON type fluorogenic sydnone(Naph-Syd) is designed as bioorthogonal probe for imaging.Sydnone moiety efficiently quenches the native fluorescence of 1,8-naphthalimide,which can be re... A novel 1,8-naphthalimide-based OFF-ON type fluorogenic sydnone(Naph-Syd) is designed as bioorthogonal probe for imaging.Sydnone moiety efficiently quenches the native fluorescence of 1,8-naphthalimide,which can be restored with the enhancement of about 300-fold,after reacting with strained cyclooctynes to form pyrazole products(Naph-Pyr).The second-order rate constant of this bioorthogonal cycloaddition can be up to 2.5 L mol^-1s^-1,which benefits imaging of biomolecules at low concentrations in cellular environment. 展开更多
关键词 Bioorthogonal cycloaddition 1 8-naphthalimide Photophysical property Sydnone Turn-on fluorescence
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Synthesis,Crystal Structure and Fluorescence Property of N-n-butyl-4-[di(bromoethyl)]amino-1,8-naphthalimide
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作者 叶非 王志强 +2 位作者 李萍 李关羽 付颖 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第5期738-744,共7页
The halogen as a kind of alkylating reagent is used to introduce new group to realize the fluorescence sensors efficient of metal ion detection. The substituent at C-4 position was double bromine, which defined that t... The halogen as a kind of alkylating reagent is used to introduce new group to realize the fluorescence sensors efficient of metal ion detection. The substituent at C-4 position was double bromine, which defined that the halogen as an alkylating reagent should be further researched and detected for Hg2+. Therefore, the N-n-butyl-4-[di(bromoethyl)]amino-1,8-naphthalimide has been synthesized to detect some metal ions. The title compound has been prepared via substitute reaction and was characterized by IR, 1H NMR, 13 C NMR, and MS. It crystallizes in triclinic, space group P1 with a = 9.0071(18), b = 9.804(2), c = 13.073(3)A, α = 73.17(3), β = 71.73(3), γ = 62.95(3)°, Z = 2, V = 961.5(3) A3, Dc = 1.666 g/cm3, F(000) = 484, μ(Mo Kα) = 4.232 mm-1, R = 0.0429 and w R = 0.1004. The presence of intermolecular hydrogen bonds as well as π-π stacking interaction led to the stability of the compound. The fluorescence intensity was obviously lower than that of other ions when Hg2+ was added with the concentration of 1 × 10^-5 mol·L-1. 展开更多
关键词 N-n-butyl-4-[di(bromoethyl)]amino-1 8-naphthalimide SYNTHESIS single crystal fluorescence
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Comparative Studies on Two 1,8-Naphthalimide Derivatives with Experimental and Theoretical Methods 被引量:1
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作者 赵朴素 景龙 +3 位作者 李玉峰 朱园 王静 建芳芳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第5期676-686,共11页
Two 1,8-naphthalimide derivatives of 7H-benzimidazo[2,1,-a]benz[de] isoquino- lin-7-one(1) and 4-bromo-7H-benzimidazo[2,1,-a]benz[de]isoquinolin-7-one(2) have been synthesized and characterized by elemental analys... Two 1,8-naphthalimide derivatives of 7H-benzimidazo[2,1,-a]benz[de] isoquino- lin-7-one(1) and 4-bromo-7H-benzimidazo[2,1,-a]benz[de]isoquinolin-7-one(2) have been synthesized and characterized by elemental analysis, IR, 1H NMR, UV-Vis and fluorescence spectra. For the two compounds, density functional theory(DFT) calculations of the structures and natural population atomic charge analysis have been performed at the B3LYP/6-311G** level of theory. Based on Onsager reaction filed model and by using TD-DFT method at the B3LYP/6-311G** level, electron spectra of 1 and 2 with solvent effect in CHCl3 solvent have been predicted, which are in agreement with the experimental ones. Comparative studies on 1 and 2 indicate that introducing an electron-withdrawing group of Br into the 4-position of naphthalene ring in 2 does not significantly make the molecular geometry of 2 different from that of 1, but evidently changes the atomic charge redistribution, moves the positive-negative charges center and then changes the dipole moment in 2. Additionally, for compound 2, the existence of Br atom has also influenced the peak intensity and peak locations in both electron and fluorescence spectra. 展开更多
关键词 1 8-naphthalimids DFT calculation atomic charge distribution electronic spectra fluorescence spectra
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Selective and Sensitive Fluorescent Chemosensors for Cu2+ Ion Based upon Bis-1,8-naphthalimide Dyads 被引量:1
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作者 Dai,Huiling Xu,Hui 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2012年第2期267-272,共6页
A series of new fluorescent chemosensors 5a--5e, composed of two aminonaphthalimide fluorophores and 2,6-bis((N-aminoalkyl)aminocarboxy)pyridines, were prepared, characterized, and their fluorescent properties to-... A series of new fluorescent chemosensors 5a--5e, composed of two aminonaphthalimide fluorophores and 2,6-bis((N-aminoalkyl)aminocarboxy)pyridines, were prepared, characterized, and their fluorescent properties to- wards heavy and transition metal (HTM) ions were investigated. Chemosensors 5e--Se exhibited high selectivity and sensitivity for Cu2+ ion over other HTM ions with fluorescent quenching (green to colourless). It clearly demonstrated that the length of the linkers (diamines) between the aminonaphthalimides and 2,6-dicarboxypyridine of 5a--Se was very important for their sensitivity and selectivity for Cu2~ ion over other HTM ions. 展开更多
关键词 fluorescence sensors 1 8-naphthalimide metal ion SELECTIVITY
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A New Fluorescent Chemosensor for Metal Ions Based upon 1,8-Naphthalimide and 8-Hydroxyquinoline
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作者 徐晖 曾习文 代会苓 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第10期2165-2168,共4页
A new fluorescent chemosensor based upon 1,8-naphthalimide and 8-hydroxyquinoline was synthesized, and its fluorescent properties in the presence of different metal cations (Hg^2+, Ag^+, Zn^2+, Fe^2+, Cd^2+, Pb^... A new fluorescent chemosensor based upon 1,8-naphthalimide and 8-hydroxyquinoline was synthesized, and its fluorescent properties in the presence of different metal cations (Hg^2+, Ag^+, Zn^2+, Fe^2+, Cd^2+, Pb^2+, Ca^2+, Cu^2+, Mg^2+, and Ba^2+) were investigated. It displayed fluorescence quenching with some heavy and transition metal (HTM) ions, and the quenching strongly depended on the nature of HTM ions. 展开更多
关键词 FLUORESCENCE SENSORS 1 8-naphthalimide 8-HYDROXYQUINOLINE metal ion
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基于Ru(dpp)_(3)Cl_(2)@ZIF-8-PDMS的光氧传感膜构建及其细胞氧微环境监测
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作者 郭婷 林海锋 +1 位作者 李红花 林玲 《分析测试学报》 北大核心 2026年第1期12-20,共9页
针对现有氧检测技术普遍存在的灵敏度不足与响应迟缓问题,该研究通过溶剂热法成功制备Ru(dpp)_(3)Cl_(2)(三(4,7-二苯基-1,10-菲咯啉)二氯化钌(Ⅱ))@ZIF-8(沸石咪唑酯骨架-8)复合纳米颗粒,并将其均匀分散于聚二甲基硅氧烷(PDMS)基体内,... 针对现有氧检测技术普遍存在的灵敏度不足与响应迟缓问题,该研究通过溶剂热法成功制备Ru(dpp)_(3)Cl_(2)(三(4,7-二苯基-1,10-菲咯啉)二氯化钌(Ⅱ))@ZIF-8(沸石咪唑酯骨架-8)复合纳米颗粒,并将其均匀分散于聚二甲基硅氧烷(PDMS)基体内,构建出新型Ru(dpp)_(3)Cl_(2)@ZIF-8-PDMS复合光氧传感膜。得益于ZIF-8的限域效应及多孔结构特性,所开发传感膜的探针荧光漂白率降低42%,氧响应灵敏度较纯PDMS膜提升2.3倍。经优化后,该传感系统成功实现了对HeLa细胞培养体系溶解氧梯度的动态实时监测,为生命科学领域的氧微环境研究提供了新型检测工具。 展开更多
关键词 氧传感器 荧光猝灭 细胞代谢 ZIF-8
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基于改进YOLOv8的森林火灾检测方法研究 被引量:1
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作者 雷建云 田祚汉 +1 位作者 夏梦 雷瑞璠 《中南民族大学学报(自然科学版)》 2026年第1期97-105,共9页
针对森林火灾检测对实时性要求较高的问题,提出了一种基于改进YOLOv8的森林火灾检测方法 .在YOLOv8的基础上,采用轻量化特征提取网络EfficientNet优化YOLOv8原主干网络CSPDarknet53,以减少计算量并提高模型的收敛速度,进而提高火灾检测... 针对森林火灾检测对实时性要求较高的问题,提出了一种基于改进YOLOv8的森林火灾检测方法 .在YOLOv8的基础上,采用轻量化特征提取网络EfficientNet优化YOLOv8原主干网络CSPDarknet53,以减少计算量并提高模型的收敛速度,进而提高火灾检测速度.此外,融入了SENet注意力机制模块,以增强网络对火灾检测的准确性.使用α-IoU损失函数代替YOLOv8原始损失函数中的CIoU损失函数来计算定位损失,该函数能够自适应地调整IoU的阈值,更好地处理不同大小和形状的目标,同时提高模型对小目标的检测性能.结果表明:该方法的平均准确率(mA@0.5P)达到了87.2%,帧率(FPS)提升了17帧,显著提高了火灾检测的实时性. 展开更多
关键词 深度学习 YOLOv8模型 森林火灾检测 实时性
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C-X-C趋化因子配体8对宫颈鳞状细胞癌模型裸鼠紫杉醇治疗敏感性的影响及机制
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作者 张华 努尔比亚·依比布拉 +3 位作者 路鹏霏 贾春丽 裴轩萱 包永星 《新乡医学院学报》 2026年第2期85-91,共7页
目的 探讨C-X-C趋化因子配体8(CXCL8)对宫颈鳞状细胞癌(CSCC)模型裸鼠紫杉醇治疗敏感性的影响及其机制。方法 通过敲低CXCL8的短发夹RNA(shRNA)慢病毒颗粒转染人CSCC Hela细胞,制备CXCL8沉默稳定表达株Hela细胞。将24只4~6周龄无特定病... 目的 探讨C-X-C趋化因子配体8(CXCL8)对宫颈鳞状细胞癌(CSCC)模型裸鼠紫杉醇治疗敏感性的影响及其机制。方法 通过敲低CXCL8的短发夹RNA(shRNA)慢病毒颗粒转染人CSCC Hela细胞,制备CXCL8沉默稳定表达株Hela细胞。将24只4~6周龄无特定病原级雌性BALB/c裸鼠随机分为模型组、CXCL8敲低组(sh-CXCL8组)、紫杉醇组和sh-CXCL8+紫杉醇组,每组6只。模型组裸鼠右侧腋窝皮下注射未经处理的Hela细胞,sh-CXCL8组裸鼠右侧腋窝皮下注射CXCL8沉默稳定表达株Hela细胞,细胞接种20 d后开始,每2 d腹腔注射无菌生理盐水100μL 1次,连续7次;紫杉醇组裸鼠右侧腋窝皮下注射未经处理的Hela细胞,sh-CXCL8+紫杉醇组裸鼠右侧腋窝皮下注射CXCL8沉默稳定表达株Hela细胞,细胞接种20 d后开始,每2 d腹腔注射紫杉醇溶液(10 mg·kg^(-1))100μL 1次,连续7次。定期监测肿瘤体积变化。末次腹腔注射后24 h处死裸鼠,以模型组为对照计算其他3组裸鼠的抑瘤率,免疫组织化学法检测各组裸鼠肿瘤组织中磷脂酰肌醇-4,5-二磷酸3-激酶催化亚基β(PIK3CB)、磷酸化蛋白激酶B1(p-AKT1)蛋白表达,实时荧光定量聚合酶链式反应法检测各组裸鼠肿瘤组织中CXCL8、B细胞淋巴瘤因子2(Bcl-2)、Bcl-2相关X蛋白(Bax)、PIK3CB、蛋白激酶B1(AKT1) mRNA的表达,Western blot法检测各组裸鼠肿瘤组织中CXCL8、Bcl-2、Bax蛋白表达。结果 sh-CXCL8组、紫杉醇组、sh-CXCL8+紫杉醇组裸鼠肿瘤质量、肿瘤组织中CXCL8、Bcl-2、PIK3CB、AKT1 mRNA相对表达量以及CXCL8、Bcl-2蛋白相对表达量显著低于模型组,抑瘤率以及肿瘤组织中Bax mRNA相对表达量显著高于模型组(P<0.05)。sh-CXCL8+紫杉醇组裸鼠肿瘤质量、肿瘤组织中PIK3CB、AKT1 mRNA相对表达量及CXCL8和Bcl-2蛋白相对表达量显著低于sh-CXCL8组和紫杉醇组,sh-CXCL8+紫杉醇组裸鼠的抑瘤率、肿瘤组织中Bax mRNA相对表达量显著高于sh-CXCL8组和紫杉醇组(P<0.05)。模型组裸鼠肿瘤组织中p-AKT1、PIK3CB蛋白在细胞核与细胞质中均呈强阳性表达;sh-CXCL8组、紫杉醇组、sh-CXCL8+紫杉醇组裸鼠肿瘤组织中p-AKT1、PIK3CB蛋白阳性表达均较模型组减弱,且主要表达于细胞质中。4组裸鼠肿瘤组织中PIK3CB蛋白的表达水平比较差异无统计学意义(Z=6.294,P>0.05);sh-CXCL8+紫杉醇组裸鼠肿瘤组织中p-AKT1蛋白表达水平显著低于模型组(P<0.05)。sh-CXCL8+紫杉醇组裸鼠肿瘤组织中Bcl-2 mRNA相对表达量显著低于sh-CXCL8组(P<0.05)。紫杉醇组、sh-CXCL8+紫杉醇组裸鼠肿瘤组织中Bax蛋白相对表达量显著高于模型组(P<0.05)。sh-CXCL8+紫杉醇组裸鼠肿瘤组织中Bax蛋白相对表达量显著高于sh-CXCL8组(P<0.05)。结论 敲低CXCL8联合紫杉醇治疗可能通过调节磷脂酰肌醇3-激酶/蛋白激酶信号通路及凋亡相关蛋白表达,提高宫颈癌细胞对紫杉醇的敏感性。 展开更多
关键词 宫颈癌 C-X-C趋化因子配体8 紫杉醇耐药 细胞凋亡
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Ce_(0.5)Zr_(0.5)O_(2)/ZIF-8催化剂的制备及应用于CO_(2)与甲醇合成碳酸二甲酯的实验研究
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作者 贾新刚 常渊富 +1 位作者 毛正浩 王文珍 《山西化工》 2026年第1期8-11,共4页
采用溶胶-凝胶法制备了网状Ce_(0.5)Zr_(0.5)O_(2)固溶体,并负载不同比例的正十二面体ZIF-8构建复合催化剂,用于催化合成碳酸二甲酯(DMC)。实验结果表明,ZIF-8的引入显著提升了反应活性,其中,Ce_(0.5)Zr_(0.5)O_(2)/40%ZIF-8表现最佳。... 采用溶胶-凝胶法制备了网状Ce_(0.5)Zr_(0.5)O_(2)固溶体,并负载不同比例的正十二面体ZIF-8构建复合催化剂,用于催化合成碳酸二甲酯(DMC)。实验结果表明,ZIF-8的引入显著提升了反应活性,其中,Ce_(0.5)Zr_(0.5)O_(2)/40%ZIF-8表现最佳。在140℃、4 MPa、4 h及脱水剂存在的优化条件下,DMC收率达27.26 mmol/g。XRD与FT-IR证实了复合材料的成功制备。XPS分析揭示了增强机理:ZIF-8与载体间的相互作用促进了Ce物种的氧化还原循环,使表面Ce^(3+)相对占比与氧空位比例分别提升至18.34%和42.36%,有效活化了反应位点。 展开更多
关键词 铈锆固溶体 ZIF-8 氧空位 DMC 催化性能
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血清IL-8、LPS表达水平与重症急性胰腺炎患者短期预后的关系
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作者 成赋斌 吴文进 《中外医学研究》 2026年第1期25-28,共4页
目的:探讨血清白细胞介素-8(IL-8)、内毒素(LPS)表达水平与重症急性胰腺炎(SAP)患者短期预后的关系,为临床早期评估患者病情及预后提供新的参考指标。方法:选取2022年1月—2025年1月于武警广东总队医院就诊的120例SAP患者为研究对象,根... 目的:探讨血清白细胞介素-8(IL-8)、内毒素(LPS)表达水平与重症急性胰腺炎(SAP)患者短期预后的关系,为临床早期评估患者病情及预后提供新的参考指标。方法:选取2022年1月—2025年1月于武警广东总队医院就诊的120例SAP患者为研究对象,根据患者短期预后情况分为预后良好组(n=98)和预后不良组(n=22),检测两组血清IL-8、LPS表达水平,分析其与患者短期预后的相关性。结果:预后不良组血清IL-8、LPS表达水平均高于预后良好组,差异有统计学意义(P<0.05)。血清IL-8、LPS表达水平均为SAP患者短期预后的独立危险因素,ROC曲线分析显示其对患者短期预后具有一定的预测价值。结论:血清IL-8、LPS表达水平与SAP患者短期预后密切相关,联合检测可为早期评估患者预后提供重要依据,为制定个性化治疗方案提供参考。 展开更多
关键词 重症急性胰腺炎 白细胞介素-8 血清 内毒素 炎症因子
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基于颜色特征量化和改进YOLO v8的番茄成熟度分级检测方法
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作者 张领先 周沁 +4 位作者 姚天雨 裴鑫达 赵立群 满杰 钱井 《农业机械学报》 北大核心 2026年第2期193-202,224,共11页
番茄的成熟度与其品质密切相关,是生产中采摘和分拣等环节的重要依据。针对作物成熟度分级检测系统功能简单,人工升级系统成本较大的问题,本文以番茄为例,采集并构建自然场景下番茄图像数据集,设计以番茄果实成熟度分级算法为基础的番... 番茄的成熟度与其品质密切相关,是生产中采摘和分拣等环节的重要依据。针对作物成熟度分级检测系统功能简单,人工升级系统成本较大的问题,本文以番茄为例,采集并构建自然场景下番茄图像数据集,设计以番茄果实成熟度分级算法为基础的番茄图像半自动标注算法对采集后的数据进行标注,在YOLO v8模型基础上,将FPN结构替换为BiFPN结构实现更高效的多尺度特征融合,利用SE注意力机制对空间和通道进行融合特征提取,引入Focal SIoU损失函数对预测框与真实框之间的角度差异进行度量,构建基于颜色特征量化和改进YOLO v8的番茄成熟度分级检测模型YOLO v8BFS,识别番茄生长过程的5个不同成熟度。试验结果表明,本文模型较好地解决了自然复杂场景下番茄成熟度分级检测的错漏检问题,在模型浮点运算量(FLOPs)、参数量(Params)和内存占用量有少量增加的条件下,本文模型的平均精度均值为94.10%相较原模型YOLO v8提高3.0个百分点。通过与Faster R-CNN-Resnet50、YOLO v5、YOLO v7-tiny、YOLO v8、YOLO v10和YOLO 11目标检测模型对比,本文在检测精度具有显著优势,为番茄成熟度的检测提供了一种可靠的方法。 展开更多
关键词 番茄成熟度 自然场景 颜色特征量化 YOLO v8
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Bifunctional fluorescent probes for hydrogen peroxide and diols based on a 1,8-naphthalimide fluorophore
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作者 SUN Wei MA Zhao +3 位作者 LI Jing LI WenHua DU LuPei LI MinYong 《Science China Chemistry》 SCIE EI CAS 2013年第10期1440-1445,共6页
This report discloses a series of naphthalimide-based bifunctional fluorescent probes for hydrogen peroxide and diols.As a result,these molecules not only demonstrated high turn-on fluorescent response and good select... This report discloses a series of naphthalimide-based bifunctional fluorescent probes for hydrogen peroxide and diols.As a result,these molecules not only demonstrated high turn-on fluorescent response and good selectivity towards hydrogen peroxide over other relevant reactive oxygen species,but also displayed different responses to diols.Therefore,these fluorescent probes could be served as sensitive,selective and practical chemosensors for both hydrogen peroxide and diols under physiologicallike conditions. 展开更多
关键词 1 8-naphthalimide bifunctional fluorescent probe hydrogen peroxide DIOLS
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基于YOLOv8-MI软枣猕猴桃小目标果实识别和定位方法
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作者 葛宜元 李奥 +3 位作者 孟庆祥 刘德江 梁秋艳 马浏轩 《农机化研究》 北大核心 2026年第4期249-257,共9页
软枣猕猴桃营养价值丰富,但由于果实小、分布密集且易受逆光影响等问题导致在自动化采摘过程中果实识别和定位精度低,严重影响采摘效率。为此,提出了一种基于YOLOv8网络结构的YOLOv8-MI软枣猕猴桃目标检测方法。对YOLOv8进行优化,主干... 软枣猕猴桃营养价值丰富,但由于果实小、分布密集且易受逆光影响等问题导致在自动化采摘过程中果实识别和定位精度低,严重影响采摘效率。为此,提出了一种基于YOLOv8网络结构的YOLOv8-MI软枣猕猴桃目标检测方法。对YOLOv8进行优化,主干网络中引入CBIM增强型空间金字塔池化模块,提升对软枣猕猴桃果实关键特征的提取能力;在颈部网络中使用Bi-FPN模块并增加小目标检测层,增强多尺度特征融合效果和小目标检测精度;在头部网络中引入MPDIoU-I损失函数动态调整学习速率,用以捕捉小目标的特征,提升果实在密集遮挡和逆光情况下的识别精度。优化结果表明:YOLOv8-MI的精确率、召回率、平均精度分别提高了8.60、7.50、6.86个百分点,模型权重仅增加了1.65 MB。在密集遮挡和逆光情况下,模型的精确率、召回率、平均精度分别提高了10.20、8.70、7.72个百分点。基于YOLOv8-MI的识别结果,运用SGBM-CL定位算法得出采摘点坐标,与人工标定数据对比,X、Y、Z方向的定位误差分别为9.09、5.98、6.10 mm,可以满足采摘精度需求。进一步对果实进行识别定位验证,系统总体识别成功率达88%,准确定位率达82%,具有较强的实用性与可靠性。 展开更多
关键词 软枣猕猴桃 小目标果实 识别定位 逆光补偿 密集遮挡 YOLOv8-MI
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基于改进YOLOv8小麦田间杂草检测方法研究
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作者 石琳 郭攀 刘志兵 《中国农机化学报》 北大核心 2026年第1期128-132,共5页
为实现智能化小麦田间杂草管理,提出一种基于改进YOLOv8小麦田间杂草检测方法。建立小麦田间杂草数据集进行模型训练、验证和测试,将C2f与全维动态卷积(ODConv)融合形成C2f—ODConv结构,以增强模型对杂草特征的提取能力;在检测头部分加... 为实现智能化小麦田间杂草管理,提出一种基于改进YOLOv8小麦田间杂草检测方法。建立小麦田间杂草数据集进行模型训练、验证和测试,将C2f与全维动态卷积(ODConv)融合形成C2f—ODConv结构,以增强模型对杂草特征的提取能力;在检测头部分加入3组SimAM注意力模块,提升模型对杂草特征的关注度;采用Inner—IoU损失函数优化模型的回归性能。结果表明,改进模型的精确率为77.48%,召回率为66.45%,平均精度均值为72.37%,相比于原YOLOv8模型分别提升3.66%、4.08%、3.15%,能够满足实际应用中对杂草检测精确度的要求。为小麦田间杂草智能检测提供技术支持,为精准农业和可持续杂草管理提供新思路。 展开更多
关键词 小麦 田间杂草 智能化除草 YOLOv8
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