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Advances in Research of Drought Stress in Major Pinus spp.: A Bibliometric Analysis and Narrative Review
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作者 Qiyu LI Qinsong LI +1 位作者 Wenxuan QUAN Chaochan LI 《Asian Agricultural Research》 2024年第4期8-13,共6页
Climate change has caused fluctuations in the frequency and severity of droughts,favoring extended periods of drought associated with anthropic actions and triggering other stressful abiotic effects that threaten terr... Climate change has caused fluctuations in the frequency and severity of droughts,favoring extended periods of drought associated with anthropic actions and triggering other stressful abiotic effects that threaten terrestrial ecosystems.As climate warming intensifies,drought is a major challenge for forest growth.Pine(Pinus Linn.)is an important genus of forest in the Northern Hemisphere and has a certain tolerance to drought.This article analyzes and reviews the advances in research about drought stress of major Pinus spp.plants in recent years and discusses understanding and future core problems.To adapt to water-deficient environments,pine plants adapt to drought by changing growth traits,closing some stomata on leaves,changing the growth and structure of roots,and adjusting their physiological activities.Moreover,the expression of specific genes is altered,causing changes in the expression of several signaling molecules and metabolites to counteract drought stress. 展开更多
关键词 pinus DROUGHT stress Growth PHYSIOLOGICAL ACCLIMATION Gene
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SMARCA4缺失型非小细胞肺癌的SPP1表达及其与PD-L1的关系 被引量:2
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作者 吴娟 黄曦 +5 位作者 李佳嘉 魏雨晴 张丽琴 俞咏梅 陆志伟 张鹤 《中国临床药理学与治疗学》 北大核心 2025年第4期477-486,共10页
目的:分析SMARCA4缺失型非小细胞肺癌中分泌性磷蛋白1(SPP1)及细胞程序性死亡-配体1(PD-L1)的表达,为罕见病理类型肺癌后续治疗研究提供科学依据。方法:回顾性分析12例SMARCA4缺失型非小细胞肺癌患者的临床与病理特征,根据其形态学分为... 目的:分析SMARCA4缺失型非小细胞肺癌中分泌性磷蛋白1(SPP1)及细胞程序性死亡-配体1(PD-L1)的表达,为罕见病理类型肺癌后续治疗研究提供科学依据。方法:回顾性分析12例SMARCA4缺失型非小细胞肺癌患者的临床与病理特征,根据其形态学分为腺癌与低分化癌两组,分析SPP1与PD-L1在两组的表达与关系。结果:所有患者均检出SPP1表达且其在低分化癌组表达水平较腺癌组显著升高(P=0.015);PD-L1表达者占6/7(5例未测),较之腺癌组,PD-L1亦在低分化癌组高表达(P=0.048),两组的PD-L1表达差异与SPP1表达差异一致。结论:SMARCA4缺失型非小细胞肺癌具有较高的SPP1及PD-L1阳性表达,病理形态为低分化癌者更甚,SPP1与PD-L1在SMARCA4缺失型非小细胞肺癌中的表达情况可能具有正相关性,其关联机制及免疫治疗中作用有待后续研究进一步探讨。 展开更多
关键词 NSCLC SMARCA4缺失 spp1 PD-L1 免疫治疗
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BDSBAS和WAAS对单频SPP精度增强对比分析
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作者 陈红英 陈韵陶 《全球定位系统》 2025年第3期82-87,共6页
星基增强系统(Satellite-Based Augmentation System,SBAS)在民航等精密定位领域的重要性逐渐凸显,但目前尚缺乏针对北斗星基增强系统(BeiDou Satellite-Based Augmentation System,BDSBAS)和广域增强系统(Wide Area Augmentation Syste... 星基增强系统(Satellite-Based Augmentation System,SBAS)在民航等精密定位领域的重要性逐渐凸显,但目前尚缺乏针对北斗星基增强系统(BeiDou Satellite-Based Augmentation System,BDSBAS)和广域增强系统(Wide Area Augmentation System,WAAS)在单频单点定位(single point positioning,SPP)应用中的性能差异对比,因此本文深入分析了SBAS对单频定位的精度增强.文章通过使用中国境内和北美地区的国际GNSS服务组织(International GNSS Service,IGS)多系统GNSS实验(Multi-GNSS Experiment,MGEX)数据,对比分析了BDSBAS和WAAS地球静止轨道(geostationary orbit,GEO)卫星的单频SPP定位效果,探讨了不同增强策略对轨道、钟差和电离层延迟的改正,验证了SBAS对定位精度的提升效果.结果显示,在各测站中,WAAS的表现优于BDSBAS,对均方根(root mean square,RMS)的最大改善达到60%,而BDSBAS在中国及周边地区也具有良好的适应性,对RMS的最大改善能达到50%,结合轨道、钟差和电离层延迟改正的策略,特别是SF_SBAS_ORB_ION在定位精度上表现最佳,在电离层影响显著的条件下,显著减少了误差并提高了定位稳定性.文章为SBAS在单频精密定位中的应用提供了新的数据支撑和参考. 展开更多
关键词 星基增强系统(SBAS) 定位增强 单频单点定位(spp) 轨道误差 电离层延迟
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SPP1在代谢相关性脂肪性肝炎中的诊断价值及调控机制
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作者 李沙 李锦忠 +3 位作者 谌宁 李敏然 戴二黑 齐亚娟 《暨南大学学报(自然科学与医学版)》 北大核心 2025年第4期505-517,共13页
目的:代谢相关性脂肪性肝炎(metabolic dysfunction-associated steatohepatitis,MASH)是代谢相关性脂肪性肝病(metabolic dysfunction-associated fatty liver disease,MAFLD)的进展阶段,目前主要依赖肝活检进行确诊,存在创伤性强、依... 目的:代谢相关性脂肪性肝炎(metabolic dysfunction-associated steatohepatitis,MASH)是代谢相关性脂肪性肝病(metabolic dysfunction-associated fatty liver disease,MAFLD)的进展阶段,目前主要依赖肝活检进行确诊,存在创伤性强、依从性差等问题。因此,亟需开发非侵入性生物标志物以辅助诊断。本研究旨在通过整合机器学习算法与肝脏转录组数据,筛选MASH关键诊断基因,并探讨分泌型磷蛋白1(secreted phosphoprotein 1,SPP1)在MASH中的调控机制及诊断价值。方法:从基因表达综合数据库(gene expression omnibus,GEO)获取MAFLD患者肝脏转录组数据集,通过差异表达分析筛选差异表达基因(differentially expressed genes,DEGs)。结合随机森林、人工神经网络、Lasso回归和支持向量机递归特征消除算法筛选关键基因,构建Neural-MASH诊断模型,并通过受试者工作特征(receiver operating characteristic,ROC)曲线评估性能。进一步分析候选关键基因与免疫细胞浸润及临床指标的相关性,并进行功能富集分析。结果:共筛选出85个DEGs,功能富集显示其与p53信号通路和细胞外基质(extra cellular matrix,ECM)-受体相互作用密切相关。通过多算法交叉验证,确定SPP1、含Fc受体样及黏蛋白结构域蛋白(fc alpha and mu receptor,FCAMR)、含黄素单加氧酶1(flavin-containing monooxygenase 1,FMO1)为关键基因,其中SPP1在MASH中表达上调,且与B细胞、巨噬细胞M0浸润及临床指标呈正相关(均P<0.05)。Neural-MASH模型在训练集和验证集中的曲线下面积(area under curve,AUC)分别为1.000和0.811。功能分析揭示SPP1主要参与ECM、细胞迁移调控、脂质定位及IL-18信号通路等生物学过程。结论:SPP1可作为MASH的潜在诊断标志物,其与免疫微环境的交互作用可能在疾病进展中发挥关键调控作用。基于机器学习所构建的Neural-MASH模型具有较高的诊断效能,可为MASH的无创诊断提供参考依据。 展开更多
关键词 代谢相关性脂肪性肝炎 分泌型磷蛋白1(spp1) 人工神经网络 生物标志物
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SPP1^(+)巨噬细胞及其表达产物CCL18在CTD-ILD中的水平及临床意义
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作者 张琳 庞春艳 +1 位作者 王永福 鲁芙爱 《包头医学院学报》 2025年第6期49-55,共7页
目的:分析结缔组织病合并间质性肺病(CTD-ILD)患者外周血中SPP1^(+)巨噬细胞的比例和其表达产物趋化因子18(CCL18)在CTD-ILD患者血清中表达水平及临床意义。方法:选取20例结缔组织病(CTD)患者和20例健康人群作为对照组,35例初诊CTD-ILD... 目的:分析结缔组织病合并间质性肺病(CTD-ILD)患者外周血中SPP1^(+)巨噬细胞的比例和其表达产物趋化因子18(CCL18)在CTD-ILD患者血清中表达水平及临床意义。方法:选取20例结缔组织病(CTD)患者和20例健康人群作为对照组,35例初诊CTD-ILD患者作为实验组,比较实验组与对照组中SPP1^(+)巨噬细胞、CCL18表达水平的差异,并与Ⅰ型胶原蛋白(COL1A1)、红细胞沉降率(ESR)、C-反应蛋白(CRP)等指标进行相关性分析。结果:与对照组相比,CTD-ILD患者外周血单核细胞中SPP1^(+)巨噬细胞比例显著增加(P<0.05),血清中CCL18的含量也明显升高(P<0.05);同时SPP1^(+)巨噬细胞、CCL18与ESR、CRP、COL1A1、肺部影像学评分(HRCT评分)呈正相关关系(P<0.05),与用力肺活量占预计值的百分比(FVC%)、一氧化碳弥散量占预计值的百分比(DLCO%)呈负相关关系(P<0.05);SPP1^(+)巨噬细胞和CCL18的曲线下面积(AUC)分别为0.732、0.939,二者联合检测的AUC为0.939,灵敏度为93.5%,特异度为83.3%,约登指数为0.768。结论:SPP1^(+)巨噬细胞及CCL18是CTD-ILD患者预后不良的因素,二者联合检测对疾病的预后具有重要的意义。 展开更多
关键词 结缔组织病合并间质性肺病 spp1^(+)巨噬细胞 趋化因子18 Ⅰ型胶原
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结直肠癌中SPP1+巨噬细胞的分布和功能及临床意义研究进展
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作者 龙雨欣 杨岳 +1 位作者 金硕(综述) 张红梅(审校) 《中国肿瘤临床》 北大核心 2025年第12期633-637,共5页
结直肠癌(colorectal cancer,CRC)是中国常见的消化道恶性肿瘤之一,其恶性进展与肿瘤微环境(tumor microenvironment,TME)的调控密切相关。肿瘤相关巨噬细胞作为TME中关键的免疫调节细胞,具有显著的异质性特征。分泌型磷蛋白1阳性肿瘤... 结直肠癌(colorectal cancer,CRC)是中国常见的消化道恶性肿瘤之一,其恶性进展与肿瘤微环境(tumor microenvironment,TME)的调控密切相关。肿瘤相关巨噬细胞作为TME中关键的免疫调节细胞,具有显著的异质性特征。分泌型磷蛋白1阳性肿瘤相关巨噬细胞(secreted phosphoprotein 1 tumor-associated macrophages,SPP1+TAM)是一类具有明确促瘤作用的亚群。SPP1+TAM在CRC组织中呈现特异性分布特征,尤其在肿瘤侵袭前沿和转移灶中显著富集。该亚群通过分泌SPP1等效应分子,参与结肠癌细胞黏附、迁移、血管生成和转移等多种活动。本文就SPP1+TAM在CRC中的分布特征、分子调控机制及其临床意义进行综述,旨在为开发新型诊断标志物和靶向治疗策略提供理论依据。 展开更多
关键词 结直肠癌 肿瘤微环境 spp1+巨噬细胞 骨桥蛋白
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Metabolic Profile Analysis and Key Metabolic Pathways Identification in Different Embryo Parts Regulating Dormancy and Germination in Pinus koraiensis
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作者 Xinghuan Li Binxi Hao +2 位作者 Shimin Cheng Ju Zhang Yuan Song 《Phyton-International Journal of Experimental Botany》 2025年第8期2499-2513,共15页
Pinus koraiensis is the dominant and constructive species of the zonal vegetation in Northeast China,known as the mixed broadleaf-Korean pine forest.Although carbohydrate metabolism pathways in the seed embryo are kno... Pinus koraiensis is the dominant and constructive species of the zonal vegetation in Northeast China,known as the mixed broadleaf-Korean pine forest.Although carbohydrate metabolism pathways in the seed embryo are known to play crucial roles during seed dormancy and germination in P.koraiensis,it remains unclear whether these metabolic pathways function differentially across tissues.P.koraiensis seeds that had undergone different durations of moist chilling in their natural environment,yielding seeds with relatively deeper primary physiological dormancy(DDS)and seeds with released primary physiological dormancy(RDS).A non-targeted metabolomic analysis was conducted on the radicle and hypocotyl-cotyledon portions of both DDS and RDS,before and after a two-week incubation under favorable conditions.Under germination conditions,RDS and DDS showed divergent metabolic profiles,especially regarding carbohydrate metabolism.Specifically,RDS seeds showed significantly reduced substrates of respiratory metabolic pathways in both radicles and hypocotyl-cotyledons.Conversely,the intermediates of the carbohydrate metabolism pathway(particularly the tricarboxylic acid cycle)accumulating in radicles of DDS seeds under germination conditions.Moreover,in RDS,the carbohydrate metabolic pathways were more prevalent in the hypocotyl-cotyledon,while lysine degradation and ascorbate and aldarate metabolism were the dominant metabolic pathways in radicles.In contrast,the tricarboxylic acid cycle showed higher activity in DDS radicles compared to hypocotyl-cotyledons.We further demonstrated that carbohydratemetabolic pathways continue to play a dominant role in both dormancy maintenance and germination processes of P.koraiensis seeds.Notably,the carbohydratemetabolism in radicles likely exerts more critical regulatory functions in these two physiological processes compared to that in cotyledon and hypocotyl tissues. 展开更多
关键词 Seed germination seed dormancy metabolism RADICLE hypocotyl-cotyledon pinus koraiensis
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Caterpillar feeding drives patterns of induced defenses and herbivore resistance in wild Pinus tabuliformis
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作者 Tianhua Sun Guona Zhou +4 位作者 Yanan Zhao Suhong Gao Jie Liu Junxia Liu Baojia Gao 《Journal of Forestry Research》 2025年第1期391-411,共21页
The defense mechanisms induced in wild Chinese pine(Pinus tabuliformis)in response to herbivores are not well characterized,especially in the field.To address this knowledge gap,we established a biological model syste... The defense mechanisms induced in wild Chinese pine(Pinus tabuliformis)in response to herbivores are not well characterized,especially in the field.To address this knowledge gap,we established a biological model system to evaluate proteome variations in pine needles after feeding by the Chinese pine caterpillar(Dendrolimus tabulaeformis),a major natural enemy and dominant herbivore.Quantitative tandem mass tag(TMT)proteomics and bioinformatics were utilized to systematically identify differentially abundant proteins implicated in the induced defense response of Chinese pine.We validated key protein changes using parallel reaction monitoring(PRM)technology.Pathway analysis revealed that the induced defenses involved phenylpropanoid,coumarin,and flavonoid biosynthesis,among other processes.To elucidate the regulatory patterns underlying pine resistance,we determined the activities of defense enzymes and levels of physiological and biochemical compounds.In addition,the expression of upstream genes for key proteins was validated by qRT-PCR.Our results provide new molecular insights into the induced defense mechanisms in Chinese pine against this caterpillar in the field.A better understanding of these defense strategies will inform efforts to breed more-resistant pine varieties. 展开更多
关键词 pinus tabuliformis Dendrolimus tabulaeformis PROTEOMICS Induced Defensive responses
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Therapeutic potential of Prevotella spp. in metabolic disorders: integrating herbal medicine and gut microbiome
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作者 Song-Yi Han Jing-Hua Wang 《Traditional Medicine Research》 2026年第2期12-19,共8页
Recently,Prevotella spp.,a major genus of gram-negative commensal bacteria in humans,have emerged as a key microbial contributor to host metabolism due to its ability to ferment dietary fibers,produce beneficial short... Recently,Prevotella spp.,a major genus of gram-negative commensal bacteria in humans,have emerged as a key microbial contributor to host metabolism due to its ability to ferment dietary fibers,produce beneficial short-chain fatty acids,and influence immune responses.However,their diversity and functional differences have created challenges for their development and therapeutic use.Recent studies have shown that specific Prevotella species,such as P.copri,P.intestinalis,and P.histicola,can strengthen gut barrier integrity and reduce metabolic imbalances.Notably,Prevotella populations can be increased through high-fiber or herbal-based treatments.Traditional herbal medicines,including fiber-rich decoctions,also demonstrate the potential to boost endogenous Prevotella communities,enhance microbial fermentation,and improve glucose and lipid balance.This perspective examines the context-dependent roles of Prevotella spp.,with emphasis on the functional heterogeneity of key species such as P.copri,suggests a framework for combining herbal modulation with species-level microbiota profiling,and outlines a research plan to explore microbe-herb synergy in treating obesity,type 2 diabetes,and related metabolic disorders.This strategy offers a new,ecology-based approach to complement standard metabolic interventions. 展开更多
关键词 gut microbiota Prevotella spp. herbal medicine metabolic diseases microbial metabolite
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Synergistic Anti-Lung Cancer and Immunomodulatory Effects of Combined Extracts from Acanthopanax sessiliflorus,Phragmites communis,and Pinus densiflora
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作者 Anjali Kariyarath Valappil Reshmi Akter +7 位作者 Muhammad Awais Dong Uk Yang Daehyo Jung Li Ling Eun Kim Kyu Hyeong Yoon Yoon Ok Lee Deok Chun Yang 《BIOCELL》 2025年第9期1771-1795,共25页
Objectives:The phytochemical investigation of traditional herbal medicines holds significant promise for modern drug discovery,particularly in cancer therapy.This study aimed to evaluate the cytotoxicity,apoptosis ind... Objectives:The phytochemical investigation of traditional herbal medicines holds significant promise for modern drug discovery,particularly in cancer therapy.This study aimed to evaluate the cytotoxicity,apoptosis induction,and immune-modulatory activities of extracts from three herbal medicines with historical use in traditional medicine—Acanthopanax sessiliflorus,Phragmites communis,and Pinus densiflora,as well as their combined extract(GMAS 01/COM),on human lung cancer cells(A549)and normal cell lines,including murine macrophages(RAW 264.7)and human keratinocytes(HaCaT).Methods:Plant extracts were prepared using aqueous extraction,sonication,and rotary evaporation.The total phenolic and flavonoid contents were quantified using the Folin-Ciocalteu and AlCl3 colorimetric methods,respectively.Antioxidant potential was evaluated via 2,2-Diphenyl-1-picrylhydrazyl(DPPH)scavenging and reducing power assays.Cytotoxicity was assessed using an MTT assay,while reactive oxygen species(ROS)generation was quantified using a 2′,7′-Dichlorodihydrofluorescein diacetate(DCFH-DA)assay.Anticancer properties,including colony formation inhibition and migration suppression,were examined using colony formation and wound healing assays.The expression of apoptotic and inflammatory mediators was analysed through qPCR.Results:GMAS 01 selectively induced apoptosis in A549 cells without cytotoxic effects on RAW264.7 and HaCaT cells.Mechanistically,it elevated intracellular ROS and activated the intrinsic mitochondrial apoptotic pathway,evidenced by p53 upregulation,increased Bax,and decreased Bcl-2 expression.GMAS 01 also significantly inhibited colony formation and migration in A549 cells.In RAW264.7 cells,it reduced nitric oxide(NO)production and downregulated iNOS,COX-2,IL-6,and IL-8,indicating strong immunomodulatory activity.Conclusion:GMAS 01 exhibits potent antioxidant,anti-inflammatory,and anticancer effects,likely mediated through ROS-induced mitochondrial apoptosis.However,mechanistic interpretations are limited by the absence of protein-level validation and pathway inhibition studies.Upcoming studies should aim to verify the underlying mechanisms and evaluate their potential for real-world application. 展开更多
关键词 ANTIOXIDANTS ROS lung cancer immune modulation Acanthopanax sessiliflorus Phragmites communis pinus densiflora apoptosis
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Desiccation and osmotic resistance mechanism of Cronobacter spp.isolated from powdered infant formula
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作者 Shiqian Fu Danliangmin Song +5 位作者 Xue Qin Lihan Wang Qianyu Zhao Chaoxin Man Xinyan Yang Yujun Jiang 《Food Science and Human Wellness》 2025年第3期968-980,共13页
Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter... Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter spp.in PIF incidents occurs from time to time,causing infant serious diseases or death.In this investigation,matrix-assisted laser desorption/ionization time of flight mass spectrometry was used to identify the phenotypes of 35 Cronobacter strains isolated from PIF and its processing environment.Subsequently,the isolates were evaluated for drying and osmotic pressure tolerance.The results showed that the deactivation rate of the strains ranged from 9.01%to 77.57%,and the highest osmotic pressure condition the strains could tolerate was 6 g/100 mL Na Cl.In addition,there was a positive correlation between biofilm formation ability and desiccation resistance.Combined with transcriptomics,Cronobacter spp.could activate biofilm synthesis,produce more trehalose,accumulate betaine and electrolytes to stabilize intracellular structure under the two treatment conditions.A total of 31 and 43 genes were found related to desiccation and permeability resistance,respectively.And some genes(cysM,thuF,ycjO,etc.)were found to be associated with two tolerances for the first time. 展开更多
关键词 Powdered infant formula Cronobacter spp. Desiccation resistance Osmotic resistance TRANSCRIPTOMICS
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The Predictive Value of SPP1 Gene Expression for the Survival of Advanced Liver Cancer Treated with Transarterial Chemoembolization
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作者 Yu Cai Pu Yan +3 位作者 Chang Tian Yuqing Li Yuanyuan Jia Siqi Wang 《Proceedings of Anticancer Research》 2025年第1期97-107,共11页
Objective:To evaluate the predictive value of secreted phosphoprotein 1(SPP1)gene expression for postoperative survival in patients with advanced liver cancer undergoing hepatic artery interventional chemoembolization... Objective:To evaluate the predictive value of secreted phosphoprotein 1(SPP1)gene expression for postoperative survival in patients with advanced liver cancer undergoing hepatic artery interventional chemoembolization treatment.Method:Bioinformatics methods,including gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis,were used to identify genes related to survival prognosis in hepatocellular carcinoma(HCC)patients.A retrospective analysis of 115 advanced liver cancer patients treated between January 2016 and October 2017 was conducted.Patients were categorized into SPP1 high-expression(n=89)and low-expression groups(n=26).Additionally,115 healthy individuals served as the control group.The relationship between SPP1 expression and clinical pathological features was analyzed.A 60-month follow-up and logistic regression analysis identified risk factors affecting survival.Results:SPP1 mRNA expression was significantly higher in liver cancer patients compared to healthy controls(P<0.05).SPP1 expression levels were significantly associated with tumor size,Child-Pugh grading,lymph node metastasis,and BCLC staging(P<0.05).High SPP1 expression,along with tumor size,Child-Pugh grading,lymph node metastasis,and BCLC staging,were independent risk factors for survival(P<0.05).The 60-month survival rate was 17.39%,with a median survival of 40 months in the low-expression group versus 18 months in the high-expression group(P<0.05).Conclusion:SPP1 expression is significantly upregulated in advanced liver cancer patients and has predictive value for postoperative survival following hepatic artery chemoembolization treatment.SPP1,combined with clinical indicators such as tumor size,Child-Pugh grading,lymph node metastasis,and BCLC staging,may serve as a prognostic biomarker for interventional treatment outcomes. 展开更多
关键词 spp1 Transarterial chemoembolization Advanced liver cancer Survival period Predictive value
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中国区域不同季节电离层修正对GPS系统SPP的影响
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作者 张春 王格 +2 位作者 张旻剑 朱一龙 王偲偲 《空间科学学报》 北大核心 2025年第3期689-702,共14页
针对中国区域,分别采用Klobuchar模型、BDGIM模型、IGS电离层格网数据,以及区域建模生成的CHNION,对2022年3月、6月、9月、12月共4个月不同纬度测站进行标准单点定位(Standard Point Positioning, SPP),通过比较SPP结果精度,对多种电离... 针对中国区域,分别采用Klobuchar模型、BDGIM模型、IGS电离层格网数据,以及区域建模生成的CHNION,对2022年3月、6月、9月、12月共4个月不同纬度测站进行标准单点定位(Standard Point Positioning, SPP),通过比较SPP结果精度,对多种电离层模型或数据在中国区域内的修正精度进行分析.研究结果表明:中国区域采用Klobuchar模型修正的SPP精度最差,相比之下, BDGIM模型4个测站平均提高定位精度20%.在中低纬度测站BJF1, ZLTG, HKSL上,采用CHINON进行电离层延迟修正后, 3个测站的每月平均定位精度依次为1.65, 1.27, 3.2, 2.87 m,采用IGS最终电离层格网数据进行电离层修正后, 3个测站的每月平均定位精度依次为1.6, 1.37, 3.1, 2.73 m. 展开更多
关键词 电离层 单点定位 KLOBUCHAR模型 BDGIM模型
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龙胆苦苷通过调节肝星状细胞中MIF-SPP1信号通路预防巨噬细胞介导的肝纤维化机制研究
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作者 王继绪 朱英斌 +1 位作者 陈茂丽 韩永峰 《细胞与分子免疫学杂志》 北大核心 2025年第7期593-602,共10页
目的探究龙胆苦苷(GPS)通过调节肝星状细胞中巨噬细胞迁移抑制因子(MIF)-分泌型磷蛋白1(SPP1)信号通路预防巨噬细胞介导的肝纤维化机制。方法将LX-2细胞分为对照组、转化生长因子β(TGF-β)组、TGF-β联合GPS(25、50、100、150)μmol/mL... 目的探究龙胆苦苷(GPS)通过调节肝星状细胞中巨噬细胞迁移抑制因子(MIF)-分泌型磷蛋白1(SPP1)信号通路预防巨噬细胞介导的肝纤维化机制。方法将LX-2细胞分为对照组、转化生长因子β(TGF-β)组、TGF-β联合GPS(25、50、100、150)μmol/mL组,EDU检测细胞增殖、Transwell TM检测细胞侵袭、Western blot法检测平滑肌激动蛋白(α-SMA)与一型胶原蛋白(COL1A1)蛋白表达。分离M1型巨噬细胞条件培养基(M1-CM)用于处理TGF-β组、TGF-β联合GPS组LX-2细胞,同时检测细胞上清液中诱导型一氧化氮合酶(iNOS)、精氨酸酶1(Arg1)浓度,细胞增殖与侵袭能力,以及α-SMA与COL1A1蛋白表达。生物信息学分析GPS、肝纤维化与巨噬细胞相关基因的靶点交集,药物亲和反应的靶点稳定性(DARTS)实验和Western blot法验证GPS对MIF的调控作用。进一步将LX-2细胞分为对照组、TGF-β组、TGF-β联合M2-CM组、TGF-β和oe-NC联合M2-CM组、TGF-β和oe-MIF联合M2-CM组,分析细胞上清液iNOS、Arg1浓度及细胞增殖、侵袭、α-SMA与COL1A1蛋白表达变化。将LX-2细胞分为对照组、TGF-β组、TGF-β联合oe-NC组、TGF-β联合oe-MIF组、TGF-β和oe-MIF联合GPS组,Western blot法测定MIF与SPP1蛋白表达。构建大鼠肝纤维化模型,探究GPS对体内肝纤维化的潜在治疗作用。结果与对照组相比,TGF-β组LX-2细胞增殖与侵袭能力增加,α-SMA与COL1A1蛋白表达增强,而GPS干预能够抑制TGF-β条件LX-2细胞增殖与侵袭,并降低α-SMA与COL1A1蛋白表达。与对照组相比,TGF-β组细胞上清液中iNOS浓度上调、Arg1浓度下降,并且M1-CM处理在TGF-β干预的基础上,进一步增加了iNOS浓度、降低了Arg1浓度,同时促进了细胞增殖与侵袭,上调了α-SMA与COL1A1蛋白表达,而GPS能够逆转M1-CM干预的结果。生物信息学分析发现MIF为GPS、肝纤维化与巨噬细胞相关基因的靶点交集之一,且GPS能够靶向并抑制其表达。相比于TGF-β组,M2-CM干预后细胞上清液中iNOS浓度下降、Arg1浓度增加,LX-2细胞增殖与侵袭能力降低,α-SMA与COL1A1蛋白表达减弱,然而过表达MIF后,逆转了M2-CM的干预效果。Western blot结果显示,相比于对照组,TGF-β组MIF与SPP1蛋白表达增强,过表达MIF后MIF与SPP1蛋白表达进一步增强,而GPS干预则抑制了MIF与SPP1蛋白表达。动物实验中,GPS干预治疗能够减轻肝纤维化大鼠肝损伤,并抑制肝组织中MIF与SPP1、α-SMA与COL1A1蛋白表达。结论GPS可能通过抑制肝星状细胞中MIF-SPP1信号通路预防巨噬细胞介导的肝纤维化。 展开更多
关键词 巨噬细胞 龙胆苦苷(GPS) 肝星状细胞 肝纤维化 巨噬细胞迁移抑制因子(MIF) 分泌型磷蛋白1(spp1)
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Design strategy of advanced generation breeding population of Pinus tabuliformis based on genetic variation and inbreeding level
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作者 Chengcheng Zhou Fan Sun +2 位作者 Zhiyuan Jiao Yousry A.El-Kassaby Wei Li 《Forest Ecosystems》 2025年第4期607-618,共12页
The level of genetic variation within a breeding population affects the effectiveness of selection strategies for genetic improvement.The relationship between genetic variation level within Pinus tabuliformis breeding... The level of genetic variation within a breeding population affects the effectiveness of selection strategies for genetic improvement.The relationship between genetic variation level within Pinus tabuliformis breeding populations and selection strategies or selection effectiveness is not fully investigated.Here,we compared the selection effectiveness of combined and individual direct selection strategies using half-and full-sib families produced from advanced-generation P.tabuliformis seed orchard as our test populations.Our results revealed that,within half-sib families,average diameter at breast height(DBH),tree height,and volume growth of superior individuals selected by the direct selection strategy were higher by 7.72%,18.56%,and 31.01%,respectively,than those selected by the combined selection strategy.Furthermore,significant differences(P<0.01)were observed between the two strategies in terms of the expected genetic gains for average tree height and volume.In contrast,within full-sib families,the differences in tree average DBH,height,and volume between the two selection strategies were relatively minor with increase of 0.17%,2.73%,and 2.21%,respectively,and no significant differences were found in the average expected genetic gains for the studied traits.Half-sib families exhibited greater phenotypic and genetic variation,resulting in improved selection efficiency with the direct selection strategy but also introduced a level of inbreeding risk.Based on genetic distance estimates using molecular markers,our comparative seed orchard design analysis showed that the Improved Adaptive Genetic Programming Algorithm(IAPGA)reduced the average inbreeding coefficient by 14.36% and 14.73% compared to sequential and random designs,respectively.In conclusion,the combination of the direct selection strategy with IAPGA seed orchard design aimed at minimizing inbreeding offered an efficient approach for establishing advanced-generation P.tabuliformis seed orchards. 展开更多
关键词 Breeding population Parental selection strategies Advanced generation seed orchard pinus tabuliformis Seed orchard design Improved Adaptive Genetic Programming Algorithm
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基于改进YOLOv3-SPP算法的道路车辆检测 被引量:7
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作者 王涛 冯浩 +4 位作者 秘蓉新 李林 何振学 傅奕茗 吴姝 《通信学报》 EI CSCD 北大核心 2024年第2期68-78,共11页
针对在城市道路场景下视觉检测车辆时,车辆密集和远处车辆呈现小尺度,导致出现检测精度低或者漏检的问题,提出了一种基于改进的YOLOv3-SPP算法,对激活函数进行优化,以DIOU-NMS Loss作为边界框损失函数,增强网络的表达能力。为提高所提... 针对在城市道路场景下视觉检测车辆时,车辆密集和远处车辆呈现小尺度,导致出现检测精度低或者漏检的问题,提出了一种基于改进的YOLOv3-SPP算法,对激活函数进行优化,以DIOU-NMS Loss作为边界框损失函数,增强网络的表达能力。为提高所提算法对小目标和遮挡目标的特征提取能力,引入空洞卷积模块,增大目标的感受野。实验结果表明,所提算法在检测车辆目标时m AP提高了1.79%,也有效减少了在检测紧密车辆目标时出现的漏检现象。 展开更多
关键词 车辆检测 YOLOv3-spp算法 激活函数 空洞卷积 深度学习
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FOSB、SPP1基因表达对经肝动脉介入化疗栓塞术治疗的中晚期肝癌生存期预测价值
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作者 燕普 蔡瑜 曾建挺 《西部医学》 2024年第7期992-997,共6页
目的探讨骨肉瘤原癌基凶同源物B(FOSB)、分泌性磷蛋白1(SPP 1)基因表达对经肝动脉介入化疗栓塞术治疗的中晚期肝癌患者术后生存期的预测价值。方法回顾性分析2016年1月—2017年10月在西安医学院第一附属医院进行诊治的中晚期肝癌患者11... 目的探讨骨肉瘤原癌基凶同源物B(FOSB)、分泌性磷蛋白1(SPP 1)基因表达对经肝动脉介入化疗栓塞术治疗的中晚期肝癌患者术后生存期的预测价值。方法回顾性分析2016年1月—2017年10月在西安医学院第一附属医院进行诊治的中晚期肝癌患者115例作为研究对象,根据FOSB、SPP 1基因表达水平分为FOSB高表达组(n=52)、FOSB低表达组(n=63)及SPP 1高表达组(n=89)、SPP 1低表达组(n=26)。同时选取115例健康体检者为健康对照组。分析FOSB、SPP 1表达与中晚期肝癌患者临床病理特征的关系。对纳入研究的患者进行为期60个月的随访,Logistics风险回归模型分析影响患者生存期的危险因素。Kaplan-Meier生存曲线分析FOSB、SPP 1表达水平与患者生存预后的关系。结果肝癌患者外周血单个核细胞中FOSB mRNA表达水平明显低于健康对照组,SPP 1 mRNA表达水平明显高于健康对照组,差异具有统计学意义(P<0.05)。FOSB、SPP 1表达在中晚期肝癌患者肿瘤大小、Child-Pugh分级、淋巴转移、BCLC分期方面比较差异具有统计学意义(P<0.05)。单因素分析结果显示,存活组和死亡组在肿瘤大小、Child-Pugh分级、淋巴转移、BCLC分期、FOSB、SPP 1表达方面比较,差异均具有统计学意义(P<0.05)。肿瘤大小、Child-Pugh分级、淋巴转移、BCLC分期、FOSB低表达、SPP 1高表达均为中晚期肝癌患者生存期的独立危险因素(P<0.05)。随访时间60个月,患者生存率为17.39%(20/115),FOSB高表达组中位生存时间为39.7个月,明显高于FOSB低表达组的19.3个月(P<0.05);SPP 1低表达组中位生存时间为40个月,明显高于SPP 1高表达组的18个月(P<0.05)。结论FOSB在中晚期肝癌患者中表达明显下调,SPP 1表达上调,其对预测中晚期肝癌患者肝动脉介入化疗栓塞术治疗生存期具有一定的价值。FOSB、SPP 1有望成为评估介入术治疗患者预后的潜在指标,可协同肿瘤大小、Child-Pugh分级、淋巴转移、BCLC分期等临床指标预测或评估肝癌患者术后生存情况。 展开更多
关键词 FOSB spp 1 经肝动脉介入化疗栓塞术 中晚期肝癌 生存期 预测价值
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SPP1和PD-L1在子宫内膜癌组织中的表达及其预后价值 被引量:1
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作者 胡帅 武霞 +2 位作者 晋雨楠 范裕裕 索玉平 《现代肿瘤医学》 CAS 2024年第21期4121-4126,共6页
目的:分析分泌型磷蛋白1(secreted phosphoprotein 1,SPP1)和程序性死亡蛋白配体1(programmed cell death-ligand 1,PD-L1)在子宫内膜癌(endometrial carcinoma,EC)组织中的表达水平及与预后的关系。方法:通过免疫组织化学方法分析SPP1... 目的:分析分泌型磷蛋白1(secreted phosphoprotein 1,SPP1)和程序性死亡蛋白配体1(programmed cell death-ligand 1,PD-L1)在子宫内膜癌(endometrial carcinoma,EC)组织中的表达水平及与预后的关系。方法:通过免疫组织化学方法分析SPP1和PD-L1在84例EC组织和61例正常子宫内膜组织中的表达情况,分析SPP1和PD-L1表达与临床病理特征及预后的关系,利用UALCAN分析工具(https://ualcan.path.uab.edu/)分析癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库中EC组织SPP1和PD-L1 mRNA的表达及与预后的关系。结果:EC组织SPP1阳性表达率高于正常子宫内膜组织(71.43%vs 36.07%,P=0.001),PD-L1阳性表达率低于正常子宫内膜组织(25.00%vs 42.62%,P=0.025);EC组织中,SPP1阳性表达率与组织学分级相关(P<0.05),PD-L1阳性表达率与淋巴结转移相关(P<0.05),SPP1与PD-L1表达呈正相关(列联系数r=0.237,P=0.026);EC组织中,不同SPP1和PD-L1表达患者总生存期无差异(均P>0.05)。TCGA数据库中生物信息学分析显示EC中SPP1 mRNA表达水平显著高于正常子宫内膜组织(P<0.01),PD-L1 mRNA表达水平与正常子宫内膜组织比较,差异无统计学意义(P=0.057);EC组织SPP1 mRNA和PD-L1 mRNA表达水平呈正相关(r=0.350,P<0.05);不同SPP1和PD-L1表达水平患者总生存期无差异(均P>0.05)。结论:SPP1在EC组织中的表达与PD-L1呈正相关,可能共同参与EC免疫微环境调控,SPP1和PD-L1均不是EC独立预后因子。 展开更多
关键词 spp1 PD-L1 子宫内膜癌 预后
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磷改性SPP沸石催化甲醇制丙烯反应
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作者 邢亚茹 刘民 郭新闻 《化学反应工程与工艺》 CAS 2024年第5期385-393,共9页
为开发甲醇制丙烯(MTP)反应的高性能催化剂,制备了不同硅铝比的SPP沸石,再进行磷改性处理。采用X射线衍射(XRD)、扫描电镜(SEM)、电感耦合等离子发射光谱(ICP)、氮气物理吸附、NH_(3)程序升温脱附(NH_(3)-TPD)和热重分析等手段表征了样... 为开发甲醇制丙烯(MTP)反应的高性能催化剂,制备了不同硅铝比的SPP沸石,再进行磷改性处理。采用X射线衍射(XRD)、扫描电镜(SEM)、电感耦合等离子发射光谱(ICP)、氮气物理吸附、NH_(3)程序升温脱附(NH_(3)-TPD)和热重分析等手段表征了样品的孔结构和酸性质等,并比较了各催化剂在甲醇制丙烯(MTP)反应中的催化性能。结果表明:相比于普通ZSM-5沸石,SPP沸石具有更大的比表面积和孔容,可以显著提高分子的扩散速率和活性位点的可接触性,提高了反应性能。得益于弱碱性磷酸铵的孔道清洁作用,磷改性后的SPP沸石的总孔容均增加。同时,随着磷改性浓度的增加,SPP沸石的强酸量逐渐降低。磷改性得到的SPP沸石(磷的质量分数为0.2%)催化MTP反应时,丙烯选择性达到50.4%,C_(2)^(=)-C_(4)^(=)选择性达到72.1%,积炭量为1.4%。 展开更多
关键词 spp沸石 磷改性 甲醇制丙烯
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Fatty Acid Profile of New Zealand Grown Edible Pine Nuts (<i>Pinus</i>spp.)
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作者 Leo P. Vanhanen Geoffrey P. Savage Richard N. Hider 《Food and Nutrition Sciences》 2017年第3期305-315,共11页
Pine nuts are becoming a popular snack because of their interesting taste and positive nutritional profile. Their fatty acid profile has been reported but there is some confusion identifying named cultivars. This stud... Pine nuts are becoming a popular snack because of their interesting taste and positive nutritional profile. Their fatty acid profile has been reported but there is some confusion identifying named cultivars. This study presents the fatty acid profile of five different cultivars of pine nuts currently growing in the South Island of New Zealand. The data are compared to three different samples of pine nuts currently imported into NZ. Identification of the twelve different fatty acids extracted from these samples was identified by retention time using GC-FID and GC-MS methods. The peaks were further identified by comparison of the retention times with a MS Library match and their corresponding LRI value. All but two of the extracted fatty acids were identified by comparisons with a known pure fatty acid standard sample for each fatty acid. Botanical identification of the five locally grown pine nuts was confirmed by calculating the Diagnostic Index of each cultivar from its fatty acid composition. 展开更多
关键词 pinus spp. Fatty Acid Profile New Zealand PINE Nuts
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