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Mammography combined with breast dynamic contrast-enhanced-magnetic resonance imaging for the diagnosis of early breast cancer 被引量:4
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作者 Yakun He Guohui Xu +4 位作者 Jin Ren bin feng Xiaolei Dong Hao Lu Changjiu He 《Oncology and Translational Medicine》 2016年第4期165-168,共4页
Objective The aim of this study was to investigate the application of mammography combined with breast dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) for the diagnosis of early breast cancer. Methods Ma... Objective The aim of this study was to investigate the application of mammography combined with breast dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) for the diagnosis of early breast cancer. Methods Mammography and DCE-MRI were performed for 120 patients with breast cancer(malignant, 102; benign; 18). Results The sensitivity of mammography for early diagnosis of breast cancer was 66.67%, specificity was 77.78%, and accuracy was 68.33%. The sensitivity of MRI for early diagnosis of breast cancer was 94.12%, specificity was 88.89%, and accuracy was 93.33%. However, the sensitivity of mammography combined with DCE-MRI volume imaging with enhanced water signal(VIEWS) scanning for early diagnosis of breast cancer was 97.06%, specificity was 94.44%, and accuracy was 96.67%. Conclusion Mammography combined with DCE-MRI increased the sensitivity, specificity, and accuracy of diagnosing early breast cancer. 展开更多
关键词 breast carcinoma mammography nuclear magnetic resonance dynamic enhancement time signal curve
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不同失血时间对犬失血性休克复苏后肝肾功能、血乳酸及氧化应激的影响
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作者 张千振 吴桐 +3 位作者 孙雪妍 孙靖博 宾峰 胡魁 《中国兽医学报》 北大核心 2025年第4期731-737,共7页
为探究不同失血时间对犬失血性休克(hemorrhagic shock,HS)复苏后肝肾功能、血乳酸(Lac)及氧化应激指标的影响,将10只健康中华田园犬随机分为失血1.5h复苏组(HSR_(A)组)和失血3.5h复苏组(HSR_(B)组)。于复苏后2、6、24、48及72h检测肝... 为探究不同失血时间对犬失血性休克(hemorrhagic shock,HS)复苏后肝肾功能、血乳酸(Lac)及氧化应激指标的影响,将10只健康中华田园犬随机分为失血1.5h复苏组(HSR_(A)组)和失血3.5h复苏组(HSR_(B)组)。于复苏后2、6、24、48及72h检测肝肾功能、Lac、氧化应激相关指标的变化。结果显示,HSR_(B)组在复苏后各个时间点的肝功能指标总胆红素(TBIL)、谷丙转氨酶(ALT)、谷草转氨酶(AST)均高于HSRA组;2组犬肾功能指标无显著变化;HSR_(B)组Lac水平在复苏后2、6h显著高于HSR_(A)组;HSR_(B)组CAT活性在复苏后2h显著低于HSR_(A)组,HSRB组GSH-px活性在复苏后2、6、24h显著低于HSR_(A)组,HSR组SOD活性在复苏后24h显著低于HSR_(A)组,HSR_(B)组MDA含量在复苏后2、6、24、48h显著高于HSR_(A)组。结果表明,HS复苏后可引起肝损伤及氧化应激反应,且随着失血时间延长,犬的肝损伤及氧化应激损伤程度加重。 展开更多
关键词 失血性休克 氧化应激 肝肾功能 血乳酸
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衣康酸及其衍生物在肝脏疾病中的作用
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作者 李明轩 孙靖博 +4 位作者 胡魁 康昕沂 孙雪妍 宾峰 张千振 《动物医学进展》 北大核心 2025年第11期116-120,共5页
衣康酸是免疫细胞三羧酸循环过程中的一种重要中间代谢物,由免疫应答基因1编码的顺乌头酸脱羧酶1催化顺乌头酸脱羧产生。作为新发现的代谢物,衣康酸成为代谢免疫学的研究热点。衣康酸能够激活巨噬细胞和调节巨噬细胞的极化,具有抗菌、... 衣康酸是免疫细胞三羧酸循环过程中的一种重要中间代谢物,由免疫应答基因1编码的顺乌头酸脱羧酶1催化顺乌头酸脱羧产生。作为新发现的代谢物,衣康酸成为代谢免疫学的研究热点。衣康酸能够激活巨噬细胞和调节巨噬细胞的极化,具有抗菌、抗炎、抗氧化的功能,在多种肝脏疾病中发挥保护作用。通过查阅近年来国内外相关文献,从衣康酸及其衍生物的来源、生理功能及在非酒精性脂肪性肝病、肝缺血再灌注损伤、脓毒症肝损伤和肝纤维化中的相关应用进行综述,以期为进一步开发和利用衣康酸及其衍生物治疗肝脏疾病提供参考。 展开更多
关键词 衣康酸 衍生物 肝脏疾病 分子机制
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Increased maternal consumption of methionine as its hydroxyl analog improves placental angiogenesis and antioxidative capacity in sows 被引量:1
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作者 Rui Zhou Shanshan Lai +13 位作者 Peiqiang Yuan Li Zhe Lunxiang Yang Yves Mercier Liang Hu Xiaoling Zhang Lun Hua Yong Zhuo Shengyu Xu Yan Lin bin feng Lianqiang Che De Wu Zhengfeng Fang 《Journal of Animal Science and Biotechnology》 2025年第4期1766-1784,共19页
Background Previous evidence suggests that methionine(Met)consumption can promote placental angiogenesis and improve fetal survival.To investigate the mechanisms by which increased levels of Met as hydroxyl-Met(OHMet)... Background Previous evidence suggests that methionine(Met)consumption can promote placental angiogenesis and improve fetal survival.To investigate the mechanisms by which increased levels of Met as hydroxyl-Met(OHMet)improve placental function,forty sows were divided into four groups and fed either a control diet,or diets supplemented with 0.15%OHMet,0.3%OHMet or 0.3%Met(n=10).Placentas were collected immediately after expulsion,and extracted proteins were analyzed by tandem mass tag based quantitative proteomic analysis.Results We found that 0.15%OHMet consumption significantly increased placental vascular density compared with the control.Proteomic analysis identified 5,136 proteins,87 of these were differentially expressed(P<0.05,|fold change|>1.2).Enriched pathways in the Kyoto Encyclopedia of Genes and Genomes for 0.15%OHMet vs.control and 0.15%OHMet vs.0.3%OHMet were glutathione metabolism;for 0.15%OHMet vs.0.3%Met,they were NOD-like receptor signaling and apoptosis.Further analysis revealed that 0.15%OHMet supplementation upregulated the protein expression of glutathione-S-transferase(GSTT1)in placentas and trophoblast cells compared with the control and 0.3%OHMet groups,upregulated thioredoxin(TXN)in placentas and trophoblast cells compared with the 0.3%OHMet and 0.3%Met groups,and decreased reactive oxygen species(ROS)levels in trophoblast cells compared with other groups.In contrast,sows fed 0.3%OHMet or 0.3%Met diets increased placental interleukin 1βlevels compared with the control,and upregulated the protein expression of complex I-B9(NDUFA3)compared with the 0.15%OHMet group.Furthermore,homocysteine,an intermediate in the trans-sulphuration pathway of Met,damaged placental function by inhibiting the protein expression of TXN,leading to apoptosis and ROS production.Conclusion Although dietary 0.15%OHMet supplementation improved placental angiogenesis and increased antioxidative capacity,0.3%OHMet or 0.3%Met supplementation impaired placental function by aggravating inflammation and oxidative stress,which is associated with cumulative homocysteine levels. 展开更多
关键词 ANGIOGENESIS Gestation sow Hydroxy-methionine analogue PLACENTA TMT Proteomics
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基于爱知生物多样性目标11的我国自然保护地管理有效性评估进展与分析 被引量:13
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作者 冯斌 李迪强 +1 位作者 张于光 薛亚东 《生物多样性》 CAS CSCD 北大核心 2021年第2期150-159,共10页
本文基于我国相关政府部门、国际机构、科研机构和文献关于我国自然保护地管理有效性评估数据,梳理和分析了我国针对爱知生物多样性目标11的自然保护地管理有效性评估的进展情况。结果显示,我国已按时完成了爱知生物多样性目标11中2015... 本文基于我国相关政府部门、国际机构、科研机构和文献关于我国自然保护地管理有效性评估数据,梳理和分析了我国针对爱知生物多样性目标11的自然保护地管理有效性评估的进展情况。结果显示,我国已按时完成了爱知生物多样性目标11中2015年之前对60%以上自然保护地管理有效性评估的指标;目前已开展管理有效性评估的自然保护地面积达136.19万km^(2),占我国自然保护地面积(186.60万km^(2))的72.99%;我国自然保护地管理有效性受多方关注。本研究调查数据与世界自然保护地数据库、自然保护地管理有效性全球数据库的数据差异较大;我国自然保护地管理有效性评估工具多样,各类型自然保护地管理有效性评估工作进展差异显著,管理有效性评估标准化和连续性有待提高。最后,提出了如下建议:加强自然保护地整体性和连通性;参考世界自然保护区委员会的评估框架和世界自然保护联盟自然保护地绿色名录标准,按照国家公园、自然保护区和自然公园分类制定管理有效性评估规范并将评估制度化;有效利用评估结果促进我国自然保护地建设的标准化、科学化并建立激励机制等。 展开更多
关键词 自然保护地 管理有效性 爱知生物多样性目标 生物多样性公约
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自然保护区减缓和适应气候变化的管理有效性评估:以广西12个典型自然保护区为例 被引量:6
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作者 冯斌 李迪强 +1 位作者 张于光 薛亚东 《生物多样性》 CAS CSCD 北大核心 2020年第8期1026-1035,共10页
建立自然保护区是生物多样性保护的根本措施,而且自然保护区对减缓和适应气候变化具有重要的作用。生物多样性保护的压力在气候变化的胁迫下不断加剧,因此,有效的自然保护区管理必须考虑气候变化的影响。发展应对气候变化威胁的适应性... 建立自然保护区是生物多样性保护的根本措施,而且自然保护区对减缓和适应气候变化具有重要的作用。生物多样性保护的压力在气候变化的胁迫下不断加剧,因此,有效的自然保护区管理必须考虑气候变化的影响。发展应对气候变化威胁的适应性管理技术以提高自然保护区管理有效性是自然保护区管理的迫切需求。但目前全球范围内还没有针对减缓和适应气候变化的自然保护区管理有效性评估工具。近半个世纪来广西气温持续升高且极端气候事件频次增加,对广西各类生物生境产生了重要的影响。本文基于世界自然保护联盟(IUCN)的自然保护区减缓和适应气候变化管理框架和管理有效性评估框架,在管理有效性跟踪工具(mangement effectiveness tracking tool,METT)基础上提出了自然保护区减缓和适应气候变化管理有效性评估工具(managementeffectiveness assessment tool of mitigation and adaptation on climate change,MEATMACC),并使用该工具和METT对广西12个典型自然保护区进行了调查分析。结果表明:国家级自然保护区的METT得分、MEATMACC得分分别比非国家级自然保护区高28.98%和43.91%;国家级与非国家级自然保护区的METT得分无显著差异,但MEATMACC得分差异极显著;两个管理有效性评估工具得分率呈线性相关但差异不显著;两个评估工具中背景、规划与影响3个要素得分率存在极显著差异。研究结果表明,对于自然保护区减缓和适应气候变化的政策和技术支持仍需加强。 展开更多
关键词 自然保护区 广西 气候变化 管理有效性评估
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Cinnamaldehyde supplementation in sows and their offspring:effects on colostrum and milk composition,performance,redox status and intestinal health
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作者 Junqi Jin Shiya Liu +9 位作者 Qiang Zhou Zhengfeng Fang Yan Lin Shengyu Xu bin feng Yong Zhuo Hefeng Luo Xiuming Liu De Wu Lianqiang Che 《Journal of Animal Science and Biotechnology》 2025年第4期1835-1850,共16页
Background Maternal nutrition significantly influences offspring development.This study investigated the effects of maternal or post-weaning cinnamaldehyde(CA)supplementation in sows and their offspring on reproductiv... Background Maternal nutrition significantly influences offspring development.This study investigated the effects of maternal or post-weaning cinnamaldehyde(CA)supplementation in sows and their offspring on reproductive performance and health.Sixty sows,selected based on body condition score and parity,were randomly allocated to control or CA(500 mg/kg)diets from d 107 of gestation to d 24 of lactation.At weaning,128 piglets were assigned to four groups(n=8)based on weight and source litter for a 21-d experiment.The four groups were CON-CON(both sow and piglet on CON),CON-CA(sow on CON,piglet on CA),CA-CON(sow on CA,piglet on CON),and CA-CA(both sow and piglet on CA).Results Maternal CA supplementation tended to improve body weight(+15%,P=0.09)and average daily gain(+21%,P=0.07)of suckling piglets,along with increased levels of milk IgG(P=0.01)and IgM(P=0.02),colostrum crude fat(P=0.01),and plasma glutathione peroxidase(GSH-Px)activity(P=0.02)at farrowing.Moreover,maternal CA supplementation significantly improved plasma antioxidant capacity,expressions of intestinal barrier and antiinflammatory genes,and gut microbiota structure of piglets at the end of suckling.Additionally,maternal CA supplementation increased the apparent total tract digestibility(ATTD)of crude protein(P<0.01),gross energy(GE;P=0.03),and dry matter(P=0.01),improved jejunal sucrase activity(P<0.01),villus height(P=0.03),the ratio of villi height to crypt depth(P=0.02),and the expressions of intestinal barrier and anti-inflammatory genes in post-weaning piglets.Furthermore,post-weaning CA supplementation tended to decrease diarrhea scores of piglets during d 14–21 and increased the ATTD of GE(P=0.02),activities of jejunal sucrase(P=0.02),plasma catalase(P=0.01),and total superoxide dismutase(P<0.01)in piglets.Conclusion Maternal CA supplementation tended to increase the growth rate and weaning weight of suckling piglets,associated with improved antioxidant capacity and milk composition.Moreover,maternal CA supplementation or post-weaning CA supplementation improved nutrient digestibility,redox status,and intestinal function-related parameters of weaned piglets. 展开更多
关键词 Antioxidant capacity CINNAMALDEHYDE Intestinal health Microbiome PIGLETS SOW
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An ESIPT-boosted NIR nanoprobe for ratiometric sensing of carbon monoxide via activatable aggregation-induced dual-color fluorescence
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作者 Min Liu bin feng +4 位作者 Feiyi Chu Duoyang Fan Fan Zheng Fei Chen Wenbin Zeng 《Chinese Chemical Letters》 2025年第5期485-491,共7页
Carbon monoxide(CO)is a crucial gaseous signaling molecule that regulates various physiological and pathological processes,and may exert an anti-inflammatory and protective role in drug-induced liver injury(DILI).Desp... Carbon monoxide(CO)is a crucial gaseous signaling molecule that regulates various physiological and pathological processes,and may exert an anti-inflammatory and protective role in drug-induced liver injury(DILI).Despite this,understanding the exact relationship between CO and the occurrence and development of DILI remains challenging.Hence,there is an urgent need to develop a reliable and robust tool for the rapid visual detection and assessment of CO in this context.Herein,we presented a novel near-infrared(NIR)fluorescent nanoprobe with aggregation-induced emission(AIE)properties and excited-state intramolecular proton transfer(ESIPT)characteristics for the detection and imaging of CO both in vitro and in vivo.Simultaneously,the nanoprobe enables self-assembly form nanoaggregates in aqueous media with high biocompatible,which can sense CO in situ through the conversion of yellowto-red fluorescence facilitated aggregation-induced dual-color fluorescence.What is more,this nanoprobe shows ratiometric respond to CO,which demonstrates excellent stability,high sensitivity(with a detection limit of 12.5 nmol/L),and superior selectivity.Crucially,this nanoprobe enables the visual detection of exogenous and endogenous CO in living cells and tissues affected by DILI,offering a user-friendly tool for real-time visualization of CO in living system.Hence,it holds great promise in advancing our understanding of CO’s role. 展开更多
关键词 Aggregation-induced emission Excited-state intramolecular proton transfer Activatable nanoprobe Carbon monoxide Imaging Assessment
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Efficacy and safety of thalidomide in the treatment of recurrent aphthous stomatitis:A systematic review
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作者 Jiao Yue Jia Ju +6 位作者 Xinwen Wang Yao Lin Jing Huang Yanfei Ma Shuibing Liu bin feng Lifei Cheng 《Journal of Chinese Pharmaceutical Sciences》 2025年第8期755-766,共12页
Thalidomide,an immunomodulatory drug,is widely recommended for the treatment of recurrent aphthous stomatitis(RAS).This review aimed to assess the reliability of thalidomide for managing RAS,oro-genital ulcers associa... Thalidomide,an immunomodulatory drug,is widely recommended for the treatment of recurrent aphthous stomatitis(RAS).This review aimed to assess the reliability of thalidomide for managing RAS,oro-genital ulcers associated with Behçet’s disease(BD),and RAS in individuals with HIV infection.A systematic review was conducted following PICOS(Patient,Intervention,Control,Outcome,Study design)principles.Given the heterogeneity across studies,a qualitative analysis was performed in place of a meta-analysis.Eight randomized controlled trials(RCTs)were deemed eligible for inclusion.In three RCTs focused on RAS,a dosage of thalidomide at 100 mg/d demonstrated efficacy,while a lower dose of 25 mg/d helped prolong the recurrence interval of RAS.For oro-genital ulcers of BD,two RCTs indicated that both 300 mg/d for 24 weeks and 200 mg/d for 28 d,preceded by an initial dose of 400 mg/d for 5 d,were effective.In three RCTs investigating RAS in HIV-infected patients,thalidomide at 200 mg/d for either 4 or 7 weeks,with an initial dose of 400 mg/d for the first week,proved effective.However,a regimen of 100 mg three times per week failed to prevent the recurrence of oral ulcers.Adverse reactions to thalidomide were generally tolerable within the dosage ranges used in these studies.Overall,thalidomide showed promising efficacy for treating RAS,oro-genital ulcers in BD,and RAS in HIV-infected individuals.However,the variability in trial designs,dosages,and treatment durations makes it challenging to recommend an optimal dose and course of therapy.Further high-quality RCTs are necessary to establish more definitive guidelines. 展开更多
关键词 Recurrent aphthous stomatitis THALIDOMIDE Behcet’s disease HIV infection Systematic review
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Dietary inulin supplementation in early gestation regulates uterine fluid exosomes and angiogenesis to improve embryo implantation in sows
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作者 Junlei Chang Xujing Pan +13 位作者 Wenyan Wei Xuemei Jiang Lianqiang Che Yan Lin Yong Zhuo bin feng Lun Hua Jian Li Jianping Wang Mengmeng Sun Xilun Zhao Ruinan Zhang De Wu Shengyu Xu 《Journal of Animal Science and Biotechnology》 2025年第6期2839-2851,共13页
Background Embryo implantation in early gestation is crucial for reproductive success,while dietary fiber plays a key role in regulating sow fertility.However,the underlying mechanisms remain unclear.This study explor... Background Embryo implantation in early gestation is crucial for reproductive success,while dietary fiber plays a key role in regulating sow fertility.However,the underlying mechanisms remain unclear.This study explores the influence of dietary inulin on embryonic implantation using a sow model.Sows were fed a diet supplemented with 11 g/kg of inulin during early gestation and were slaughtered on gestation day 19(G19).Uterine fluid exosomes(UFEs)and endometrial tissues were collected for high-throughput sequencing and for analysis of the expression of angiogenesis-related genes and proteins,respectively.Furthermore,UFEs obtained from slaughtered sows were injected into G19 sows to investigate the effects on reproduction and angiogenesis.Results The results showed that inulin significantly increased the number of blood vessels in the endometrium and expression of the angiogenesis-related proteins MMP2 and ANGPT1 in G19 sows(P<0.05).Bioinformatics analysis revealed that inulin significantly downregulated miRNAs associated with angiogenesis inhibition in UFEs,while upregulating miRNAs related to trophoblast physiological activities and regulation of the uterine fluid microenvironment(P<0.05).Furthermore,intravenous injection of G19 sows with UFEs from sows fed a diet containing inulin had significantly promoted vascular formation in the endometrium and embryos,and increased the number of live embryos on gestation day 28(G28)(P<0.05).Additionally,the mRNA expression levels of MMP2,ANGPT1,and VEGF in the placentas of sows were significantly elevated on G28 and at farrowing in the UFEs injection group(P<0.05).Conclusion Dietary supplementation with inulin during early gestation in sows promoted embryo implantation by regulating angiogenesis at the maternal–fetal interface through the modulation of miRNA expression in UFEs.These findings provide a theoretical reference for the application of dietary fiber in sow nutrition. 展开更多
关键词 ANGIOGENESIS Embryo implantation EXOSOME INULIN SOW
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Research on the hazards of gas leakage and explosion in a full-scale residential building
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作者 Chengjun Yue Li Chen +2 位作者 Zhan Li bin feng Ruizhi Xu 《Defence Technology(防务技术)》 2025年第1期168-181,共14页
The gas explosion in residential building has always been a highly concerned problem.Explosions in homogeneous mixtures have been extensively studied.However,mixtures are often inhomogeneous in the practical scenarios... The gas explosion in residential building has always been a highly concerned problem.Explosions in homogeneous mixtures have been extensively studied.However,mixtures are often inhomogeneous in the practical scenarios due to the differences in the densities of methane and air.In order to investigate the effects of gas explosions in inhomogeneous mixtures,experimental studies involving gas leakage and explosion are conducted in a full-scale residential building to reproduce the process of gas explosion.By fitting the dimensionless buoyancy as a function of dimensionless height and dimensionless time,a distribution model of gas in large-scale spaces is established,and the mechanism of inhomogeneous distribution of methane is also be revealed.Furthermore,the stratified reconstruction method(SRM)is introduced for efficiently setting up inhomogeneous concentration fields in FLACS.The simulation results highlight that for the internal overpressure,the distribution of methane has no effect on the first overpressure peak(ΔP1),while it significantly influences the subsequent overpressure peak(ΔP2),and the maximum difference between the overpressure of homogeneous and inhomogeneous distribution is174.3%.Moreover,the initial concentration distribution also has a certain impact on the external overpressure. 展开更多
关键词 Methane distribution Inhomogeneous mixture Gradient layer Gas explosion Explosive simulation
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Debut of a responsive chemiluminescent probe for butyrylcholinesterase:Application in biological imaging and pesticide residue detection
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作者 Shuaige Bai Shuai Huang +5 位作者 Ting Luo bin feng Yanpeng Fang Feiyi Chu Jie Dong Wenbin Zeng 《Chinese Chemical Letters》 2025年第3期222-226,共5页
Butyrylcholinesterase(BChE)is a key enzyme in the metabolism of cholinergic compounds.It has been recognized as a key biomarker for many diseases,including liver diseases and Alzheimer’s disease.However,classical met... Butyrylcholinesterase(BChE)is a key enzyme in the metabolism of cholinergic compounds.It has been recognized as a key biomarker for many diseases,including liver diseases and Alzheimer’s disease.However,classical methods for detecting BChE activity suffer from low sensitivity,cumbersome pre-treatment,and poor stability.Chemiluminescence is a promising new method for detecting and imaging the activity of BChE.It has several advantages over traditional methods,including low background interference,high sensitivity,and the absence of external illumination.In this study,we developed a novel BChE-activatable chemiluminescent probe(CL-BChE).It exhibited a significant chemiluminescence enhancement at 525nm upon incubation with BChE.It had a low limit of detection(6.25×10^(−3)U/mL)and was highly selective for BChE.CL-BChE was used to image BChE activity in living cells and tumor-bearing animal models.It was also successfully applied to detect pesticide residue,even under the interference of representative phytochromes and real vegetable samples.Given its high sensitivity,selectivity,and versatility,we believe that CL-BChE will be a promising tool for investigating BChE’s activity in biomedical research as well as other BChE-related scenarios. 展开更多
关键词 BUTYRYLCHOLINESTERASE CHEMILUMINESCENCE Tumor imaging Pesticide residue detecting BIOASSAYS
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Yak and Tibetan sheep mixed grazing enhances plant functional diversity in alpine grassland
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作者 Yuzhen Liu Xinquan Zhao +4 位作者 Xiaoxia Yang Wenting Liu bin feng Shengnan Sun Quanmin Dong 《Journal of Integrative Agriculture》 2025年第3期936-948,共13页
The response of plant functional diversity to external disturbances not only effectively predicts changes in the ecosystem but it also reflects how plant communities use external environmental resources.However,resear... The response of plant functional diversity to external disturbances not only effectively predicts changes in the ecosystem but it also reflects how plant communities use external environmental resources.However,research on how different herbivore assemblages affect plant functional diversity is limited.Therefore,this study systematically explored the effects of three typical herbivore assemblages(yak grazing,Tibetan sheep grazing,and mixed grazing by yaks and Tibetan sheep)on species richness,plant functional diversity,and soil physicochemical properties in alpine grasslands on the Qinghai-Tibet Plateau,China.This study further investigated the primary mechanisms driving the changes in plant functional diversity.The results indicate four key aspects of this system:(1)Grazing significantly enhanced plant functional diversity,particularly when the mixed grazing by yaks and Tibetan sheep was applied at a ratio of 1:2.This ratio showed the most substantial improvement in the functional dispersion index and Rao's quadratic entropy index.(2)Compared to enclosed treatments,grazing increased species richness andβ-diversity,contributing to higher plant functional diversity.(3)Grazing treatments affected various plant traits,such as reducing plant community height and leaf thickness while increasing specific leaf area.However,the impact on plant functional diversity was most pronounced under the mixed grazing by yaks and Tibetan sheep at a ratio of 1:2.(4)Speciesα-diversity was positively correlated with plant functional diversity.Changes in plant functional diversity were primarily regulated by variations in soil physicochemical properties.Specifically,increases in soil available nitrogen significantly promoted changes in plant functional diversity,while increases in soil available potassium and bulk density had a significant inhibitory effect on these changes.Long-term grazing significantly reduced the height of plant communities in alpine meadows,while a balanced mixture of yak and Tibetan sheep grazing,especially at a ratio of 1:2,enhanced plant functional diversity the most.This suggests that,under these conditions,the use of external environmental resources by the plant community is optimized. 展开更多
关键词 alpine grassland adaptive management herbivore assemblages species diversity functional diversity
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抵钉座经肛置入法腹部无切口手术与腹腔镜直肠前切除术的对比研究 被引量:2
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作者 冯斌 王茂峰 +5 位作者 吴磊 曹艳茹 张飞妍 祝青 司世同 常凤华 《中国肿瘤临床》 CAS CSCD 北大核心 2021年第16期834-838,共5页
目的:探讨抵钉座经肛置入法腹部无切口手术(natural orifice specimen extraction surgery,NOSES)与腹腔镜直肠前切除术(laparoscopic anterior rectectomy,LAR)的临床效果比较。方法:回顾性分析2019年1月至2020年1月在菏泽市立医院接... 目的:探讨抵钉座经肛置入法腹部无切口手术(natural orifice specimen extraction surgery,NOSES)与腹腔镜直肠前切除术(laparoscopic anterior rectectomy,LAR)的临床效果比较。方法:回顾性分析2019年1月至2020年1月在菏泽市立医院接受治疗的60例中低位直肠癌患者的临床资料,其中NOSES组(n=30)作为观察组行抵钉座经肛置入法肛门外翻切除标本腹部无切口手术,对照组(n=30)行LAR,对比分析两组术中和术后各临床相关指标。术后随访6~12个月,观察肿瘤复发情况。结果:两组患者手术均顺利完成,无中转开腹病例,两组术中出血量、术中淋巴结清扫数目、术后并发症发生率、肿瘤复发率等差异无统计学意义(P>0.05);NOSES组手术时间、术后疼痛评分、首次下床活动时间、肛门排气时间、首次进食时间、住院时间均优于对照组,差异有统计学意义(P<0.05)。结论:NOSES治疗中低位直肠癌安全可行、效果满意。相比传统腹腔镜手术具有手术时间短、术后疼痛轻、下床活动早、肛门排气早、进食时间早、住院时间短、腹部无切口疤痕、快速康复等优点,而术后并发症及肿瘤复发率无明显增加,值得临床上推广应用。 展开更多
关键词 中低位直肠癌 腹腔镜直肠前切除手术 外翻技术 经自然腔道外翻切除标本腹部无切口手术 对比研究
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含DGs的配网多阶段故障恢复 被引量:1
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作者 汪沨 丁阳 +2 位作者 陈春 宾峰 吕建红 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2019年第4期55-64,共10页
针对含分布式电源(DGs)的配网快速故障恢复问题,提出了一种多阶段故障恢复方法.该故障恢复方法有机融合了故障拓扑识别、孤岛划分、含DGs主网连通性恢复和网络重构、切负荷操作四个阶段.当配电网发生故障时,采用故障拓扑识别法分析故障... 针对含分布式电源(DGs)的配网快速故障恢复问题,提出了一种多阶段故障恢复方法.该故障恢复方法有机融合了故障拓扑识别、孤岛划分、含DGs主网连通性恢复和网络重构、切负荷操作四个阶段.当配电网发生故障时,采用故障拓扑识别法分析故障区域,确定下一步故障恢复执行阶段并更新失电区的拓扑参数;孤岛配置阶段,提出了深度优先搜索算法的孤岛划分方法,以优先恢复关键负荷和最大化负荷恢复量为目标,并提高DGs利用率;采用启发式规则优选联络开关迅速恢复失电区与主网的连通性;网络重构阶段基于父子链表规则避免了不可行解的产生,潮流计算验证是否执行下一阶段;切负荷阶段切除非关键负荷以保证系统稳定运行.算例表明:该方法适用于含DGs的配电网发生大面积停电、多重故障、连锁故障等情况,能根据实际情况制定有效恢复策略,提高了复杂故障恢复的效率,具有很强的适用性. 展开更多
关键词 配电网 故障恢复 分布式电源 孤岛划分 网络优化
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基于超导SQUID的全张量梯度计的研制
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作者 郑婷 孙文娟 +1 位作者 宾峰 陆勤龙 《低温与超导》 CAS 北大核心 2024年第9期22-29,共8页
SQUID是已知最灵敏的磁传感器之一,可以应用在地球物理、矿产资源勘探、科学研究以及军事应用等方面。本文采用一阶SQUID平面梯度计组成全张量梯度计,使用不平衡度补偿算法对全张量梯度计进行补偿,仿真结果显示,该方法在不同测试环境下... SQUID是已知最灵敏的磁传感器之一,可以应用在地球物理、矿产资源勘探、科学研究以及军事应用等方面。本文采用一阶SQUID平面梯度计组成全张量梯度计,使用不平衡度补偿算法对全张量梯度计进行补偿,仿真结果显示,该方法在不同测试环境下都有效减少了不平衡度引入的噪声,据此仿真结构搭建了全张量梯度计,且通过实验测试了9个通道数据的稳定输出,包括6个一阶SQUID平面梯度计和3个SQUID磁强计,计算得到磁场梯度数据。结果表明梯度数据优于地球环境磁场,该系统有益于磁场梯度测量的应用。 展开更多
关键词 SQUID 磁梯度计 全张量 不平衡度
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浅谈公猪养殖过程中的营养问题
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作者 林燕 方正锋 +7 位作者 车练强 冯斌 徐盛玉 李健 卓勇 江雪梅 赵希仑 吴德 《猪业科学》 2021年第5期37-41,共5页
公猪在养猪生产中的重要性日益突出,然而由于人们对公猪营养的研究相对较少,尚有许多问题困扰着行业的发展。文章就养猪生产上十分关注的一些问题进行简单的描述和分析,以为规模化养殖场种公猪营养的制定提供依据和参考。
关键词 公猪 营养 肢蹄 季节
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雷达对低温微波器件的应用需求分析
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作者 阮祥伟 左涛 +4 位作者 陆勤龙 宾峰 孙文娟 刘洋 王生旺 《低温与超导》 CAS 北大核心 2020年第6期55-59,共5页
分析了雷达系统对低温微波器件的应用需求,从技术原理、关键技术、使用性价比等角度展开论证,并对技术方向与应用前景提出个人观点。分析表明:航天测控类雷达在高灵敏接收领域对低温微波器件应用需求迫切,在X频段系统G/T值可因此提高3.8... 分析了雷达系统对低温微波器件的应用需求,从技术原理、关键技术、使用性价比等角度展开论证,并对技术方向与应用前景提出个人观点。分析表明:航天测控类雷达在高灵敏接收领域对低温微波器件应用需求迫切,在X频段系统G/T值可因此提高3.85~7.03倍;在拥挤的P/L/S频段,窄带超导滤波器组能有效改善地面警戒等雷达的抗干扰性能;在V/W等毫米波段,低温微波器件能降低噪声2 dB^5 dB,对毫米波段雷达噪底的降低有重要应用价值。 展开更多
关键词 低温器件 超导器件 雷达 应用
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计及电磁模特高频信号的局部放电模式识别方法 被引量:15
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作者 辛文成 姚森敬 +6 位作者 陈浩敏 席禹 张凡 敖榜 宾峰 林晓青 汪沨 《电力科学与技术学报》 CAS 北大核心 2022年第6期108-115,共8页
特高频(UHF)法局部放电检测已经成为高压GIS及变压器等设备常用的运维检测手段,但由于该方法是通过测量电磁波间接检测局部放电强度,使得基于该方法的局部放电模式识别技术准确率不高,而且一直没有得到很好的解决。本文引入TE_( m1)模... 特高频(UHF)法局部放电检测已经成为高压GIS及变压器等设备常用的运维检测手段,但由于该方法是通过测量电磁波间接检测局部放电强度,使得基于该方法的局部放电模式识别技术准确率不高,而且一直没有得到很好的解决。本文引入TE_( m1)模截止频率作为PD UHF信号时频分布图的分割依据,对单一绝缘缺陷激发的PD UHF信号进行预处理、时频分布图分割、特征参数提取和选择以及PSO-ELM识别等操作,最终可准确判断出PD信号类型,提高GIS绝缘缺陷类型的识别准确率。这种分割方法增强了图谱特征的空间分布信息,对改善特高频法识别局部放电的准确率具有实际应用价值。 展开更多
关键词 气体绝缘组合电器 局部放电 模式识别 电磁模
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可穿戴手语翻译设备在聋哑人教学中的应用研究
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作者 宾峰 马家辉 +2 位作者 任鹏 陈伟荷 李文琪 《科学与信息化》 2023年第8期138-140,共3页
为解决聋哑人的交流问题,设计了一种基于手势识别的穿戴式手语翻译器。该装置通过六轴陀螺仪和应变传感器采集手部数据并传输给STM32微处理器,采用模板匹配-神经网络混合算法分析出正确的手语动作,通过语音播报模块将手语信息以语音形... 为解决聋哑人的交流问题,设计了一种基于手势识别的穿戴式手语翻译器。该装置通过六轴陀螺仪和应变传感器采集手部数据并传输给STM32微处理器,采用模板匹配-神经网络混合算法分析出正确的手语动作,通过语音播报模块将手语信息以语音形式播报,打破了传统聋哑人手语课堂教学的局限性,具有识别速度快、准确率高、便携、耐磨等优点。 展开更多
关键词 手语翻译 语音播报 聋哑教学
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