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基于GF-1和Landsat 9卫星影像融合的农作物分类
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作者 曾伟丽 苏巧梅 +3 位作者 范锦龙 潘蓉 廖月娇 宋影 《太原理工大学学报》 北大核心 2026年第1期52-59,共8页
【目的】拟利用GF-1和Landsat 9卫星影像的融合技术,提高农作物分类的准确度。【方法】采用PC Spectral Sharpening(PC)、Gram-Schmidt Pan Sharpening(GS)和NNDiffuse Pan Sharpening(NN)三种融合模型,对GF-1 WFV与Landsat 9卫星影像... 【目的】拟利用GF-1和Landsat 9卫星影像的融合技术,提高农作物分类的准确度。【方法】采用PC Spectral Sharpening(PC)、Gram-Schmidt Pan Sharpening(GS)和NNDiffuse Pan Sharpening(NN)三种融合模型,对GF-1 WFV与Landsat 9卫星影像的红、绿、蓝和近红外4个波段进行融合,采用均值、标准差和信息熵对融合结果进行评价,得到最佳融合波段,借助随机森林分类算法对GF-1 WFV影像、Landsat 9影像和最佳融合影像进行农作物分类。【结果】结果表明,融合GF-1和Landsat 9影像的分类模型相较于单一影像的模型,在农作物分类的准确性和稳定性上均有显著提升,分类总体精度达到92.9%,Kappa系数达到0.92,F1 Score为87.4%。融合后的影像作物分类总体精度、Kappa系数、F1 Score分别比GF-1 WFV影像的分类提高了1.7%,0.2,0.6%;比Landsat 9影像的分类提高了3.2%,0.4,4.4%。采用GF-1 WFV近红外波段,运用NN算法对Landsat 9数据进行融合,融合影像在农作物分类方面表现良好,该方法可广泛应用于大范围内的农作物信息精细提取。 展开更多
关键词 遥感 影像融合 gf-1 Landsat 9 农作物分类
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香蕉线条病毒GF SYBR Green Ⅰ实时荧光定量PCR检测方法的建立
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作者 卢咏思 刘润沛 +1 位作者 毛自先 饶雪琴 《仲恺农业工程学院学报》 2026年第1期11-15,共5页
香蕉线条病毒GF(Banana Streak Virus GF,BSGFV)是一种危害香蕉的主要香蕉线条病毒(Banana Streak Virus,BSV),为高效检测该病毒,本研究根据BSGFV外壳蛋白(Coat Protein,CP)基因的保守序列设计特异性引物,建立了SYBR Green Ⅰ实时荧光定... 香蕉线条病毒GF(Banana Streak Virus GF,BSGFV)是一种危害香蕉的主要香蕉线条病毒(Banana Streak Virus,BSV),为高效检测该病毒,本研究根据BSGFV外壳蛋白(Coat Protein,CP)基因的保守序列设计特异性引物,建立了SYBR Green Ⅰ实时荧光定量PCR(Fluorescence Quantitative PCR,qPCR)方法.结果表明,qPCR检测特异性引物BSGFV-qG3F/qG3R的最适宜浓度为0.2μmol/L,最适退火温度为59℃.qPCR可以检测到最低质粒浓度为1.0×10^(2) copies/μL,检测质粒的灵敏度是PCR的100倍,检测体系Ct值的变异系数小于5%.所建立的qPCR方法只适用于田间主栽品种如巴西蕉(AAA)等香蕉中BSGFV的检测,不适用于含B基因组的杂交种香蕉中BSGFV的检测.本研究为田间主栽品种香蕉中BSGFV的诊断和防控奠定了基础. 展开更多
关键词 香蕉线条病毒 香蕉线条病毒gf 内源性香蕉线条病毒gf SYBR GreenⅠ实时荧光定量PCR
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基于敦煌辐射校正场的GF-6/PMS时序绝对辐射定标方法
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作者 彭书杰 张运杰 +4 位作者 韦玮 李新 黄冬 张勇 郑小兵 《应用光学》 北大核心 2026年第1期177-186,共10页
为确保高分六号全色多光谱相机(GF-6 panchromatic and multispectral sensor,GF-6/PMS)遥感数据在精准农业的应用效果,需及时校准载荷辐射性能参数。提出基于敦煌辐射校正场的GF-6/PMS自动化在轨辐射定标方法,实现了2019年7月至2024年1... 为确保高分六号全色多光谱相机(GF-6 panchromatic and multispectral sensor,GF-6/PMS)遥感数据在精准农业的应用效果,需及时校准载荷辐射性能参数。提出基于敦煌辐射校正场的GF-6/PMS自动化在轨辐射定标方法,实现了2019年7月至2024年11月期间GF-6/PMS过境敦煌场38次的时序绝对辐射定标,结果不确定度优于4.15%,并分析了场地均匀性对结果的影响。根据有效定标结果建立载荷辐射性能衰变模型,分析出各波段辐射定标系数年变化在0.16%~1.21%。此外,以Sentinel-2/MSI为参考的GF-6/PMS载荷除全色波段外的各波段辐射衰变模型在敦煌场、Railroad Valley场以及La Crau场验证中,相对差异绝对均值在2.34%~4.12%,证明了该文对GF-6/PMS自动化在轨定标方法的有效性,为保障GF-6/PMS遥感产品应用提供了数据支撑。 展开更多
关键词 时序辐射定标 场地均匀性分析 gf-6/PMS 趋势分析 交叉验证
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Linking starch particle physicochemical properties to functionality in medicinal plants:Insights from Polygonum multiflorum and Smilax glabra 被引量:1
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作者 Nan Wang Lingling Wu +2 位作者 Yaya Su Haifeng Tang Hailong Yuan 《Chinese Chemical Letters》 2026年第1期487-491,共5页
This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared ... This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared spectroscopy,X-ray diffraction,high-performance anion-exchange chromatography,and differential scanning calorimetry.Significant differences were observed in their morphological,physicochemical,and functional properties.PMS had a smaller particle size(13.68 μm),irregular polygonal shape,A-type,lower water absorption(62.67 %),and higher oil absorption(51.17 %).In contrast,SGS exhibited larger particles(31.75 μm),a nearly spherical shape,B-type,higher crystallinity(50.66 %),and greater amylose content(21.54 %),with superior thermal stability,shear resistance,and gelatinization enthalpy.SGS also contained higher resistant starch(83.28 %) and longer average chain length(20.58 %),but showed lower solubility,swelling power,light transmittance,and freeze-thaw stability.The physicochemical properties differences in crystal pattern and particle morphology between PMS and SGS lead to distinct behaviors during in vitro digestion and fermentation.These findings highlight the potential of medicinal plant starches in functional ingredients and industrial processes. 展开更多
关键词 Starch particle Physicochemical properties Starch function Resistant starch Starch extraction
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The Analysis of Gauss Radial Basis Functions and Its Application in Locating Olivine on the Moon
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作者 SONG Shicang SONG Xiaoyuan SONG Shuhan 《应用数学》 北大核心 2026年第1期173-181,共9页
Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the m... Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the main contributions is proving this property using linear algebra instead of profound knowledge.This makes it easy to read and understand this fundamental fact.The proof of linear independence of a set of Gauss functions relies on the constructing method for one-dimensional space and on the deducing method for higher dimensions.Additionally,under the condition of preserving the same moments between the original function and interpolating function,both the interpolating existence and uniqueness are proven for GRBF in one-dimensional space.The final work demonstrates the application of the GRBF method to locate lunar olivine.By combining preprocessed data using GRBF with the removing envelope curve method,a program is created to find the position of lunar olivine based on spectrum data,and the numerical experiment shows that it is an effective scheme. 展开更多
关键词 Gauss function Radial basis function Machine learning Lunar olivine locating Data fitting
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基于GF-2影像的防护林退化程度识别研究
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作者 王荣 范燕敏 +3 位作者 刘文惠 李天兰 向泽群 王宇轩 《现代农业科技》 2026年第2期128-135,142,共9页
防护林作为干旱区的重要生态屏障,在保障农业可持续发展和区域生态安全方面发挥着关键作用。本文以新疆生产建设兵团第二师为研究区,基于高分二号(GF-2)遥感影像和770条实地调查的已知退化等级防护林条带,开展防护林退化程度识别研究。... 防护林作为干旱区的重要生态屏障,在保障农业可持续发展和区域生态安全方面发挥着关键作用。本文以新疆生产建设兵团第二师为研究区,基于高分二号(GF-2)遥感影像和770条实地调查的已知退化等级防护林条带,开展防护林退化程度识别研究。提取大气阻抗植被指数(ARVI)、差值植被指数(DVI)、增强植被指数(EVI)、归一化植被指数(NDVI)、红绿植被指数(RGVI)、比值植被指数(RVI)和土壤调整植被指数(SAVI)7个植被指数,分析其与郁闭度、断带率、枯死木与濒死木比例等退化指标之间的相关性。结果表明:NDVI与防护林退化指标之间具有显著相关性,DVI和SAVI在退化等级判别中亦表现优良。基于植被指数的阈值构建退化识别模型,对3种代表性指数进行分级,确定防护林退化的阈值标准。与人工地面调查结果对比显示,单指标模型识别精度可达71%,进一步融合多项退化指标构建的多指标组合模型识别精度提高至82%。研究表明,融合多植被指数与多源退化特征的综合方法在防护林退化识别中具有较高的适用性和准确性,为干旱区防护林生态监测提供了有效的技术支持。 展开更多
关键词 卫星遥感 防护林 退化程度 植被指数 gf-2影像
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Electroacupuncture Improves Gastrointestinal Motility in Rats with Functional Dyspepsia via the GDNF/GFRα1/PI3K/Akt Signaling Pathway
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作者 Li Zhou Xiao-li Pan +3 位作者 De-qian Yang Qi Chen Pai-di Xu Hong-xing Zhang 《Current Medical Science》 2025年第4期957-965,共9页
Objective Abnormal gastrointestinal motility plays a crucial role in the pathogenesis of functional dyspepsia(FD).Although electroacupuncture(EA)has demonstrated efficacy in FD treatment,its precise mechanism remains ... Objective Abnormal gastrointestinal motility plays a crucial role in the pathogenesis of functional dyspepsia(FD).Although electroacupuncture(EA)has demonstrated efficacy in FD treatment,its precise mechanism remains unclear.This study aimed to elucidate the specific mechanism through which EA improves gastrointestinal motility in FD.Methods Physiological indices,including body weight,food intake,gastrointestinal motility,and gastrointestinal morphology,were utilized to assess the FD model in rats.EA interventions were applied at meridian points,as well as non-meridian points and non-acupoints,in FD model rats.The effects of EA at zusanli(ST36)and taichong(LR3)on gastrointestinal motility in FD model rats were elucidated using gastrointestinal motility test indices.Techniques such as Western blotting,quantitative real-time PCR,and immunofluorescence were employed to determine the specific mechanisms by which EA improved gastrointestinal motility in FD model rats.Results Multifactorial stress intervention could be used to effectively establish an FD rat model.EA at ST36 and LR3 significantly improved gastrointestinal motility.Furthermore,EA at ST36 and LR3 upregulated the protein expression of glial cell line-derived neurotrophic factor(GDNF),GDNF family receptor alpha 1(GFRα1),phosphatidylinositol 3-kinase(PI3K),and protein kinase B(Akt),along with their mRNA expression levels and the number of enteric glial cells(EGCs).Conclusions EA was capable of increasing the number of EGCs by activating the GDNF/GFRα1/PI3K/Akt signaling pathway,thereby improving gastrointestinal motility in FD. 展开更多
关键词 functional dyspepsia ELECTROACUPUNCTURE Enteric nervous system Enteric glial cell Gastrointestinal motility
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基于GF-3雷达数据极化分解与深度学习的干旱区绿洲土地覆被及盐渍化分级研究
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作者 刘翔宇 张飞 依力亚斯江·努尔麦麦提 《新疆师范大学学报(自然科学版)》 2026年第2期58-70,共13页
土地利用/覆被演变研究是解析人地关系的重要科学议题,其精准监测对区域可持续发展决策具有支撑作用。本研究以克里雅绿洲为研究对象,基于高分三号(GF-3)全极化合成孔径雷达数据与Landsat 8-OLI多光谱数据,结合野外实测土壤理化参数,构... 土地利用/覆被演变研究是解析人地关系的重要科学议题,其精准监测对区域可持续发展决策具有支撑作用。本研究以克里雅绿洲为研究对象,基于高分三号(GF-3)全极化合成孔径雷达数据与Landsat 8-OLI多光谱数据,结合野外实测土壤理化参数,构建多源遥感协同分类体系。将土壤盐渍化分级(轻度、中度、重度)作为土地覆被质量的核心量化指标,与土地利用类型(耕地、植被、水体、裸地)共同构成分类框架。通过应用八种极化分解方法、随机森林特征优选算法及U-Net深度学习模型,系统探讨干旱区绿洲土地利用/覆被分类的最优解译方案。实验结果表明,相较于传统影像分类算法,U-Net深度学习框架在分类精度指标上呈现显著优势,其总体分类精度提升至78.21%,Kappa系数达0.72.该模型有效融合雷达后向散射特征、光学光谱特征及土壤有机质含量等理化参数,通过多维特征空间构建解决植被-盐渍化混合像元的同谱异质问题。本研究提出的多源数据融合分类方法为绿洲生态系统监测提供了新的技术支撑,其分类结果的空间异质性解析能力为绿洲土地退化防治与资源管理决策提供了可靠的科学依据。 展开更多
关键词 积神经网络 gf-3 极化分解 克里雅绿洲 土地利用/覆被
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Microglia overexpressing brain-derived neurotrophic factor promote vascular repair and functional recovery in mice after spinal cord injury 被引量:2
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作者 Fanzhuo Zeng Yuxin Li +6 位作者 Xiaoyu Li Xinyang Gu Yue Cao Shuai Cheng He Tian Rongcheng Mei Xifan Mei 《Neural Regeneration Research》 2026年第1期365-376,共12页
Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in s... Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury. 展开更多
关键词 ANGIOGENESIS apoptosis brain-derived neurotrophic factor colony stimulating factor 1 receptor inflammation MICROGLIA motor function spinal cord injury vascular endothelial growth factor
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X inactive-specific transcript regulates mitochondrial function and neuronal differentiation of stem cells via IGF2BP2/CPT1A axis in models of spinal cord injury
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作者 Si-Xiang Zeng Jin-Tao Ye +1 位作者 Si-Hua Huang Ruo-Xi Liu 《World Journal of Stem Cells》 2025年第7期131-142,共12页
BACKGROUND Spinal cord injury(SCI)often results in irreversible neurological deficits;therefore,effective treatment is urgently needed.Neural stem cells(NSCs)have excellent differentiation potential.However,the role o... BACKGROUND Spinal cord injury(SCI)often results in irreversible neurological deficits;therefore,effective treatment is urgently needed.Neural stem cells(NSCs)have excellent differentiation potential.However,the role of the long noncoding RNA X inactive-specific transcript(XIST)in NSCs and SCI remains unclear.AIM To explore the role of XIST in enhancing NSC function and its therapeutic potential in SCI.METHODS We used in vitro and in vivo models to examine the effects of XIST on NSCs.XIST was overexpressed in NSCs,and its impact on mitochondrial function,neuronal differentiation,and the insulin-like growth factor 2 mRNA binding protein 2(IGF2BP2)/carnitine palmitoyl transferase 1A(CPT1A)pathway was assessed using a series of biochemical assays,quantitative PCR,and Seahorse XF24 analysis.A mouse model of SCI was used to evaluate the therapeutic effects of XIST in vivo.RESULTS Overexpression of XIST in NSCs significantly increased mitochondrial membrane potential,ATP production,and oxygen consumption rate.XIST also promoted NSC proliferation and neuronal differentiation while inhibiting astrocytic differentiation.Mechanistically,XIST regulated CPT1A expression post-transcriptionally by interacting with IGF2BP2.In vivo XIST-treated mice exhibited improved motor scores and reduced proinflammatory cytokine expression following SCI.CONCLUSIONThese findings suggested that XIST modulated mitochondrial function and neural differentiation in NSCs throughthe IGF2BP2/CPT1A pathway. While preliminary in vivo results are encouraging, further studies are needed todetermine the long-term therapeutic relevance and underlying mechanisms of XIST in SCI recovery. 展开更多
关键词 Spinal cord injury Neural stem cell X inactive-specific transcript Mitochondrial function Neuronal differentiation
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弹性网络和XGBoost联合的GF-1卫星滩涂光伏提取方法
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作者 左婧霏 刘荣杰 纪永刚 《海洋科学进展》 北大核心 2026年第1期125-140,共16页
卫星遥感技术是滩涂光伏监测的主要技术手段,但光伏遥感的研究主要聚焦于陆地光伏。滩涂光伏具有明显不同于陆地光伏的特征,而且其背景环境复杂,准确提取难度大。针对该问题,本文基于高分一号(GF-1)卫星遥感数据,利用弹性网络开展了滩... 卫星遥感技术是滩涂光伏监测的主要技术手段,但光伏遥感的研究主要聚焦于陆地光伏。滩涂光伏具有明显不同于陆地光伏的特征,而且其背景环境复杂,准确提取难度大。针对该问题,本文基于高分一号(GF-1)卫星遥感数据,利用弹性网络开展了滩涂光伏空谱响应特征遴选,遴选出蓝光波段反射率、绿光波段反射率、均值、归一化水体指数(Normalized Difference Water Index, NDWI)、信息熵、红蓝波段差和比,以及亮度七个可表征滩涂光伏的特征,并基于XGBoost算法构建了滩涂光伏提取方法。实验结果表明,本文所提方法在不同滩涂光伏区域均取得了较好的提取效果,召回率达86.28%,F1分数达0.91;与支持向量机(Support Vector Machine, SVM)、随机森林算法(Random Forest, RF)相比,本文所提方法的召回率和F1分数分别提高10%和7%以上。该方法具有误提率低、边缘提取精度高和训练速度快等优势,可为滩涂光伏遥感监测提取提供有效的技术支撑。 展开更多
关键词 滩涂光伏 光伏提取 gf-1 WFV XGBoost 弹性网络
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The characteristics of cerebral cortical oxygenation levels and functional connectivity under upper and lower limb exercise-induced fatigue
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作者 Feng Li Yajie Wang +3 位作者 Xinyi Wang Jiawei Bi Ye Luo Lingyan Huang 《Sports Medicine and Health Science》 2026年第1期61-69,共9页
This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fati... This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fatigue was induced using an upper limb ergometer or a lower limb ergometer,with the load increasing gradually each minute.fNIRS covering the prefrontal cortex and motor cortex were used to collect data during the resting state,both before and after fatigue induction.A two-way ANOVA was conducted to examine differences in oxyhemoglobin(HbO_(2))and functional connectivity before and after fatigue induction in both groups,with the significance level set at 0.05.Exercise-induced fatigue in both the upper and lower limbs leads to a significant decrease in cerebral cortical oxygenation levels.Upper limb fatigue leads to a significant reduction in functional connectivity,there were significant decreases in connectivity within the motor cortex,between the motor cortex and frontal regions,and between the right ventrolateral prefrontal cortex and other frontal regions.Conversely,no significant changes were observed before and after lower limb fatigue.Future studies should focus on examining the extent to which how changes in the cerebral cortex,induced by exercise fatigue,are linked to exercise-and/or performance-related outcomes. 展开更多
关键词 Brain functional connectivity Cerebral oxygenation level Exercise-induced fatigue functional near-infrared spectroscopy
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Artificial intelligence in functional gastrointestinal disorders:From precision diagnosis to preventive healthcare
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作者 Yi-Nan Yan Jing-Qi Zeng Xia Ding 《Artificial Intelligence in Gastroenterology》 2026年第1期20-35,共16页
Functional gastrointestinal disorders(FGIDs),including irritable bowel syndrome(IBS),functional dyspepsia(FD),and gastroesophageal reflux disease(GERD),present persistent diagnostic and therapeutic challenges due to s... Functional gastrointestinal disorders(FGIDs),including irritable bowel syndrome(IBS),functional dyspepsia(FD),and gastroesophageal reflux disease(GERD),present persistent diagnostic and therapeutic challenges due to symptom heterogeneity and the absence of reliable biomarkers.Artificial intelligence(AI)enables the integration of multimodal data to enhance FGID management through precision diagnostics and preventive healthcare.This minireview summarizes recent advancements in AI applications for FGIDs,highlighting progress in diagnostic accuracy,subtype classification,personalized interventions,and preventive strategies inspired by the traditional Chinese medicine concept of“treating the undiseased”.Machine learning and deep learning algorithms have demonstrated value in improving IBS diagnosis,refining FD neuro-gastrointestinal subtyping,and screening for GERD-related complications.Moreover,AI supports dietary,psychological,and integrative medicine-based interventions to improve patient adherence and quality of life.Nonetheless,key challenges remain,including data heterogeneity,limited model interpretability,and the need for robust clinical validation.Future directions emphasize interdisciplinary collaboration,the development of multimodal and explainable AI models,and the creation of patientcentered platforms to facilitate a shift from reactive treatment to proactive prevention.This review provides a systematic framework to guide the clinical application and theoretical innovation of AI in FGIDs. 展开更多
关键词 Artificial intelligence functional gastrointestinal disorders Irritable bowel syndrome functional dyspepsia Gastroesophageal reflux disease
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Functional genes associated with the occurrence of mycotoxins produced by Aspergillus in foods
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作者 Mei Gu Can Liu +4 位作者 Xiaofeng Yue Du Wang Xiaoqian Tang Qi Zhang Peiwu Li 《Journal of Integrative Agriculture》 2026年第2期585-601,共17页
Aspergillus species are ubiquitous fungi that produce mycotoxins(secondary metabolites)known as sterigmatocystin and aflatoxins in many different kinds of foods,which leads to serious contamination in agricultural pro... Aspergillus species are ubiquitous fungi that produce mycotoxins(secondary metabolites)known as sterigmatocystin and aflatoxins in many different kinds of foods,which leads to serious contamination in agricultural products,thereby endangering human health.Extensive studies on Aspergillus fungi have been conducted on growth and development,aflatoxin biosynthesis,and their interactions with environment.Here,we summarized a series of functional genes of the main Aspergillus fungi relative to toxins occurrence in foods,which revealed the signal transduction mechanisms of their involvement in growth and development,toxin production,and response to light,anticipating providing theoretical guidance on developing control and prevention technologies for mycotoxin contamination in agricultural products to ensure food safety. 展开更多
关键词 functional genes ASPERGILLUS AFLATOXIN DEVELOPMENT
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结合GF-1多尺度特征与Sentinel-1结构特征的土地利用分类及碳储量估测
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作者 唐淑兰 张旻曦 《生态环境学报》 北大核心 2026年第2期190-198,共9页
碳中和背景下陆地生态系统碳储量的精细化估测具有重要意义。为更精确地利用多源遥感影像调查陆地生态系统碳储量情况,该文提出融合高分1号(GF-1)多尺度特征及哨兵1号(Sentinel-1)结构特征的土地利用分类及碳储量估测方法。对GF-1经特... 碳中和背景下陆地生态系统碳储量的精细化估测具有重要意义。为更精确地利用多源遥感影像调查陆地生态系统碳储量情况,该文提出融合高分1号(GF-1)多尺度特征及哨兵1号(Sentinel-1)结构特征的土地利用分类及碳储量估测方法。对GF-1经特征向量主成分分析的主分量影像进行小波包变换,依据代价函数选出最优小波包树,提取多尺度特征,再结合植被指数特征、Sentinel-1结构特征构造分类向量,利用随机森林(RF)筛选特征完成土地利用分类,最后基于In VEST模型估测碳储量。结果表明:1)GF-1光谱及小波包纹理融合Sentinel-1结构特征后,各土地利用分类总体精度可达92.46%,Kappa为0.91,估测的碳储量值为31.27 Tg,与实测碳储量值相比总体误差为0.81%;2)分类后各土地利用类型中,林地、住宅、水域、耕地、道路、园地、其他未利用土地占比分别为83.29%、2.32%、1.38%、4.44%、1.29%、6.42%、0.86%,对应的碳储量贡献占比分别为91.53%、0.03%、0.08%、2.77%、0.01%、5.50%、0.08%;3)该文方法较仅用GF-1光谱特征估测碳储量的误差降低了3.09%。可见,光学影像经最优小波包变换提取多尺度特征,再结合Sentinel-1的垂直特征,细化了地物分类,提高了碳储量的估测精度。该方法可为碳储量的遥感估测提供借鉴。 展开更多
关键词 土地利用分类 碳储量估测 小波包变换 融合高分1号(gf-1) 哨兵1号(Sentinel-1)
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Csp^(2)-H functionalization as an efficient catalytic route to carbazoles
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作者 Giulia Brufani Edoardo Bazzica +2 位作者 Yanlong Gu Francesco Mauriello Luigi Vaccaro 《Chinese Chemical Letters》 2026年第1期39-56,共18页
Given the broad applicability of carbazole structural moieties in materials science and medicinal chemistry,significant efforts have been devoted to developing efficient synthetic catalytic methodologies to access thi... Given the broad applicability of carbazole structural moieties in materials science and medicinal chemistry,significant efforts have been devoted to developing efficient synthetic catalytic methodologies to access this valuable scaffold.Catalyzed direct Csp^(2)-H functionalization provides an effective and costefficient approach to synthesizing carbazoles from simple and readily available starting materials,ensuring a promising path characterized by excellent atom and step economy.This review highlights the substantial progress made in the last 10 years in advancing catalytic Csp^(2)-H functionalization techniques for synthesizing carbazoles. 展开更多
关键词 C-H functionalization CARBAZOLES Synthetic methodologies CATALYSIS
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Effects of using multivitamins as dietary supplements on cognitive function in older adults:a systematic review and meta-analysis
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作者 Yijia Xu Yueqiao(Elle)Wang +1 位作者 Guoxun Chen Rui Li 《Food Science and Human Wellness》 2026年第1期1-12,共12页
Multivitamins were widely used health supplements that replenished essential nutrients in the human body.Despite their popularity,the impact of multivitamins on the cognitive function of older adults remained unclear ... Multivitamins were widely used health supplements that replenished essential nutrients in the human body.Despite their popularity,the impact of multivitamins on the cognitive function of older adults remained unclear and contentious.This study offered a comprehensive review and meta-analysis of research published until June 2024,analyzing the effects of multivitamins on various cognitive functions in individuals aged 65 and older.We included ten randomized controlled trials encompassing 13,600 participants from multiple databases.These studies evaluated the impact of multivitamins on reasoning,memory,learning,visual perception,idea production,cognitive speed,psychomotor abilities,and higher cognitive functions.Our meta-analysis revealed that multivitamins significantly enhanced delayed free recall(SMD=0.09,95%confidence interval(CI)=[0.05,0.13],P=0.0001).However,they had no substantial effects on immediate free recall(SMD=0.85,95%CI=[-0.1,1.9],P=0.11),idea production(SMD=0.00,95%CI=[-0.04,0.03],P=0.86),or cognitive functioning(SMD=0.07,94%CI=[-0.07,0.14],P=0.006).Thus,while multivitamins facilitated delayed free recall,they did not significantly improve other cognitive functions in older adults. 展开更多
关键词 MULTIVITAMINS Cognitive function Older adults META-ANALYSIS
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Silent cardiac burden:Echocardiographic abnormalities and their predictors in kidney transplant candidates and their impact on graft function
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作者 Nihal Mohammed Sadagah Muhammad Abdul Mabood Khalil +3 位作者 Hinda Hassan Khideer Mahmood Ibtisam Ali Alghamdi Ghada Abdulrahman Buridi Salem H Al-Qurashi 《World Journal of Transplantation》 2026年第1期167-181,共15页
BACKGROUND An echocardiogram is an essential tool in the evaluation of potential kidney transplant recipients(KTRs).Despite cardiac clearance,potential KTRs still have structural and functional abnormalities.Identifyi... BACKGROUND An echocardiogram is an essential tool in the evaluation of potential kidney transplant recipients(KTRs).Despite cardiac clearance,potential KTRs still have structural and functional abnormalities.Identifying the prevalence of these abnormalities and understanding their predictors is vital for optimizing pretransplant risk stratification and improving post-transplant outcomes.AIM To determine the prevalence of left ventricular hypertrophy(LVH),left ventricular systolic dysfunction(LVSD),diastolic dysfunction(DD),pulmonary hypertension(PH),and their predictors,and to assess their impact on graft function in pre-transplant candidates.METHODS The study included all successful transplant candidates older than 14 who had a baseline echocardiogram.Binary logistic regression models were constructed to identify factors associated with LVH,LVSD,DD,and PH.RESULTS Out of 259 patients,LVH was present in 64%(166),12%(31)had LVSD,27.5%(71)had DD,and 66(25.5%)had PH.Independent predictors of LVH included male gender[odds ratio(OR):2.51;95%CI:1.17-5.41 P=0.02],PH(OR=2.07;95%CI:1.11-3.86;P=0.02),DD(OR:2.47;95%CI:1.29-4.73;P=0.006),and dyslipidemia(OR=1.94;95%CI:1.07-3.53;P=0.03).Predictors for LVSD included patients with DD(OR=3.3,95%CI:1.41-7.81;P=0.006)and a family history of coronary artery disease(OR=4.50,95%CI:1.33-15.20;P=0.015).Peritoneal dialysis was an independent predictor for DD(OR=10.03;95%CI:1.71-58.94,P=0.011).The presence of LVH(OR=3.32,95%CI:1.05-10.55,P=0.04)and mild to moderate or moderate to severe mitral regurgitation(OR=4.63,95%CI:1.45-14.78,P=0.01)were significant factors associated with PH.These abnormalities had no significant impact on estimated glomerular filtration at discharge,6 months,1 year,or 2 years post-transplant.CONCLUSION Significant echocardiographic abnormalities persist in a potential transplant candidate despite cardiac clearance,although they don’t affect future graft function.Understanding the risk factors associated with these abnormalities may help clinicians address these factors pre-and post-transplant to achieve better outcomes. 展开更多
关键词 Echocardiographic abnormalities Kidney transplant PREDICTORS Graft function
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Research Progress and Network Pharmacological Analysis of Single Herb Improvement of Functional Dyspepsia by Jineijin Shanzha(Galli Gigerii Endothelium Corneum and Crataegi Fructus)Traditional Chinese Medicine Patch
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作者 Yingbing HE Tianbao ZHANG Quan SHI 《Medicinal Plant》 2026年第1期10-19,共10页
[Objectives]To investigate the efficacy and potential mechanism of the topical preparation Jineijin-Shanzha Patch(composed of Galli Gigerii Endothelium Corneum and Crataegi Fructus)in improving functional dyspepsia(FD... [Objectives]To investigate the efficacy and potential mechanism of the topical preparation Jineijin-Shanzha Patch(composed of Galli Gigerii Endothelium Corneum and Crataegi Fructus)in improving functional dyspepsia(FD)based on network pharmacology.[Methods]Firstly,we reviewed the existing research progress on each constituent drug of the Jineijin Shanzha Patch for FD improvement.Following this,identified overlapping genes were utilized to construct both a"Drug-Active Component-FD Target"network and a Protein-Protein Interaction(PPI)network specific to the patch.In addition,Gene Ontology(GO)analysis was carried out.[Results]We identified that the 13 herbs in the Jineijin Shanzha Patch are mainly used for food stagnation,qi stagnation,and spleen deficiency.Screening revealed 43 active patch components,1414 FD-related targets,and 284 shared targets between them.The PPI network analysis further identified the top 10 core targets from these shared targets.From the"Drug-Active Component-FD Target"network,we identified the core elements.These included the herbal components Vignae Semen(from Liushenqu),Crataegi Fructus,and Pseudostellariae Radix;the active components quercetin,genistein,and apigenin;and the key targets CASP3,BCL2,and CASP9.GO analysis of the 284 overlapping targets indicated that the Jineijin Shanzha Patch may exert its therapeutic effects via regulation of biological processes such as the response to lipopolysaccharide,response to bacterium-derived molecules,and regulation of the apoptotic signaling pathway.[Conclusions]The main active components of the Jineijin Shanzha Patch(quercetin,genistein,and apigenin)may improve FD by modulating signaling pathways such as the response to lipopolysaccharide,response to bacterium-derived molecules,and regulation of the apoptotic signaling pathway,thereby acting on key targets including CASP3,BCL2,and CASP9. 展开更多
关键词 Medicinal plant functional dyspepsia Action mechanism Network pharmacology
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Development of an in situ small intestinal injection technique for targeted macromolecule delivery and in vivo functional studies in mice
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作者 Yawen Lai Xintao Zhang +5 位作者 Tingting Luo Wenhan Chen Chenyu Ma Haihua Luo Jinghua Liu Jia Xu 《Animal Models and Experimental Medicine》 2026年第1期128-141,共14页
Background:Targeted delivery of biological macromolecules to the small intestine remains challenging due to their susceptibility to degradation in the hostile gastric environment.Methods:This study introduces a minima... Background:Targeted delivery of biological macromolecules to the small intestine remains challenging due to their susceptibility to degradation in the hostile gastric environment.Methods:This study introduces a minimally invasive,in situ injection technique for the murine small intestine that facilitates localized luminal delivery while circumventing gastric barriers.The procedure involves a small abdominal incision for direct injection into the duodenum near the pylorus.Postsurgical monitoring of physiological parameters,systemic inflammatory markers,liver function,and intestinal integrity was conducted over 72 h.Histopathological analysis was performed.The delivery of the functional protein TAT-EGFP(Tat protein fused to enhanced green fluorescent protein)to intestinal epithelial cells was evaluated and compared with oral gavage.As a proof of concept,single-cell RNA sequencing of the intestinal epithelium was performed after high-mobility group box 1 administration.Results:Postsurgical monitoring indicated only transient,anesthesia-related hypo-thermia and minor behavioral alterations.No significant changes were observed over 72 h in body weight,core temperature,clinical severity scores,systemic inflammatory markers(C-reactive protein and leukocytes),liver function(alanine aminotransferase),or intestinal integrity.Histopathological analysis confirmed preserved tissue architec-ture and normal digestive,absorptive,and barrier functions.The model successfully delivered TAT-EGFP to intestinal epithelial cells,an outcome not achievable via oral gavage due to gastric degradation.Single-cell RNA sequencing of the intestinal epi-thelium after high-mobility group box 1 administration revealed inflammatory gene expression patterns in specific epithelial subpopulations.Conclusions:Compared to traditional methods such as oral gavage or organoid cul-ture,this technique offers precise,degradation-resistant delivery of macromolecules in a physiological context.The model's versatility makes it a powerful platform for intestinal research,with applications in drug delivery assessment,gene therapy evalu-ation,and host-microbiota interaction studies. 展开更多
关键词 animal models intestinal drug delivery protein function
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