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Optimizing a multimedia model to assess the differential roles of crops and natural vegetation in the fate of PAHs
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作者 Chao Su Danfeng Zheng +7 位作者 Wenlei Chen Kifayatullah Khan Hong Zhang Shuai Song Ruoyu Liang Xiaoyu Zhang Yong Liu Xianghui Cao 《Journal of Environmental Sciences》 2026年第1期413-423,共11页
Vegetation plays an important role in the environmental transport behavior of organic pollutants,however,the different roles of crops and natural vegetation have been ignored in most previous studies.In this study,we ... Vegetation plays an important role in the environmental transport behavior of organic pollutants,however,the different roles of crops and natural vegetation have been ignored in most previous studies.In this study,we developed the BETR-Urban-Rural-Veg model to quantitatively evaluate the influences of both natural vegetation and crops on the multimedia transport processes of Phenanthrene(PHE)and Benzo(a)pyrene(BaP)in mainland of China.The geographic distribution of polycyclic aromatic hydrocarbon(PAH)emissions and concentrations were consistent,displaying higher levels in northern China while lower levels in southern China.Under seasonal simulations,for both natural vegetation and crops,PAH concentrations in winter and spring were 1.5 to 27-fold higher than in summer and autumn,especially for PHE.Owing to the higher leaf area index(LAI)of natural vegetation and harvesting of crops,the filter and sequestration effect of natural vegetation was stronger than crops,while the seasonal changes of PAH concentrations in crops were more significant than natural vegetation.Temperature,precipitation rates and LAI might have important influences on seasonal concentrations and overall persistence of PAHs.PHE was more sensitive to the impacts of seasonal environmental parameters.Under different landscape scenarios,average annual PAH concentrations in natural vegetation were always a little higher than those in crops,and the overall persistence of BaP was greatly affected increasing by 15.15%-16.47%.This improved model provides a useful tool for environmental management.The results of this study are expected to support land use plans and decision-making in China's mainland. 展开更多
关键词 Multimedia fate model Natural vegetation CROPS Seasonal variabilities Landscape scenarios
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Accumulation characteristics and fate modeling of phthalic acid esters in surface water from the Three Gorges Reservoir area,China 被引量:2
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作者 Shuai Sun Bing Zhang +6 位作者 Junjie Hu Wen Gu Zhen Wang Deling Fan Feng Ge Lili Shi Lei Wang 《Journal of Environmental Sciences》 2025年第3期46-56,共11页
Phthalic acid esters(PAEs)are a group of compounds widespread in the environment.To investigate the occurrence and accumulation characteristics of PAEs,surface water samples were collected from the Three Gorges Reserv... Phthalic acid esters(PAEs)are a group of compounds widespread in the environment.To investigate the occurrence and accumulation characteristics of PAEs,surface water samples were collected from the Three Gorges Reservoir area,China.The total concentrations of∑_(11)analyzed PAEs(11PAEs)in the collected water samples ranging from 197.7 to 1,409.3 ng/L(mean±IQR:583.1±308.4 ng/L).While DEHP was the most frequently detected PAE,DnBP and DnNP were the most predominant PAEs in the analyzed water samples with a mean contribution of 63.3%of the∑_(11)PAEs.The concentrations of the∑_(11)PAEs in the water samples from the upper reaches of the Yangtze River were significantly higher than those from themiddle reaches.To better understand the transport and fate of the PAEs,seven detected PAEs were modeled by Quantitative Water Air Sediment Interaction(QWASI).The simulated and measured values were close for most PAEs,and differences are within one order of magnitude even for the worst one.For all simulated PAEs,water and particle inflow were main sources in the reservoir,whereas water outflow and degradation in water were important removal pathways.The contribution ratios of different sources/losses varied fromPAEs,depending on their properties.The calculated risk quotients of DnNP in the Three Gorges Reservoir area whether based onmonitoring or simulating results were all far exceeded the safety threshold value,implying the occurrence of this PAE compound may cause potential adverse effects for the aquatic ecology of the Three Gorges Reservoir area. 展开更多
关键词 Phthalic esters Surface water Transport and fate Three Gorges Reservoir area Risk assessment
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Dedifferentiation and redifferentiation:the developing cell fate transition of plants
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作者 Asia Maqbool Mengxiao Lu +4 位作者 Noor Muhammad Naila Mir Baz Mengjun Liu Zhiguo Liu Lixin Wang 《Horticultural Plant Journal》 2025年第6期1961-1984,共24页
Plant cells retain the ability for cellular reprogramming,including totipotency and pluripotency,enabling them to revert their cell fate from differentiated to dedifferentiated one and subsequently redifferentiate und... Plant cells retain the ability for cellular reprogramming,including totipotency and pluripotency,enabling them to revert their cell fate from differentiated to dedifferentiated one and subsequently redifferentiate under specific physiological and environmental cues.In response to these cues,endogenous phytohormones,genetic landscapes,and epigenetic remodeling play a significant role in initiating the reprogramming of somatic cells and re-establishment of an organized structure.Detailed studies on dedifferentiation have gradually unraveled the involvement of stem-like cells during early callus formation,along with the existence of QC-like transcriptional features in the middle cell layer of callus,which exhibits organ regeneration ability.Tracking natural variations and real-time regeneration dynamics across species,combined with single-cell RNA sequencing,will enable the identification of key developmental regulators and small peptides.These breakthroughs can be applied to enhance regeneration efficiency,improve transformation in recalcitrant species,and accelerate next-generation crop development.The current review summarizes the longstanding history and ongoing research progress in two pathways:dedifferentiation and redifferentiation.It also highlights how hormonal effects on the genetic factors and provides insights into how genetic signatures interact with epigenetic landscapes to drive these processes.It highlights the potential applications of developmental regulators for efficient gene transformation to enhance plant genetic engineering,while also addressing fundamental questions and identifying research gaps to guide future studies. 展开更多
关键词 DEDIFFERENTIATION REDIFFERENTIATION Cell fate transition Developmental regulators Gene transformation APPLICATIONS
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Negotiable Fate Belief and Suicidal Ideation among Left-Behind Children:The Mediating Role of Coping Self-Efficacy and Gender Differences
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作者 Xiao Hu Biao Li Jun Qin 《International Journal of Mental Health Promotion》 2025年第8期1203-1220,共18页
Objectives:Suicidal ideation is a strong predictor of suicide deaths,which refers to the consideration or desire to give up one's own life.Left-behind children in rural China are more vulnerable to psychological p... Objectives:Suicidal ideation is a strong predictor of suicide deaths,which refers to the consideration or desire to give up one's own life.Left-behind children in rural China are more vulnerable to psychological problems and suicidal ideation compared to their non-left-behind peers.The aim of the current study was to examine two potential protective factors,negotiable fate belief and coping self-efficacy,and to test the mediating role of coping self-efficacy in the relationship between negotiable fate belief and suicidal ideation.We also analyzed gender differences in this mediation model.Methods:Across-sectional survey was conducted in rural areas ofChina.A sample of 526 left-behind children(285 males,54.18%;241 females,45.82%;Meanage=13.29 years,SD=0.97 years)was recruited to complete the Negotiable Fate Belief Scale,Coping Self-Efficacy Scale,and the Positive and Negative Suicide Ideation Inventory-Negative Scale.We used structural equation modeling to test the mediation model and multigroup analysis to test the moderation effect of gender.Results:Negotiable fate belief is negatively correlated with suicidal ideation(r=-0.13,p<0.01).Moreover,coping self-efficacy mediates the relationship between negotiable fate belief and suicidal ideation(β=-0.06,95%confidence interval(CI)[-0.12,-0.02]),accounting for 35.29%of the total effect.Finally,the mediating effect of coping self-efficacy was found to be significant only for female left-behind children(male:95%CI[-0.09,0.07];female:95%CI[-0.16,-0.01]).For female left-behind children,the mediating effect was complete,with a coefficient of-0.06,accounting for 85.71%of the total effect.Conclusions:The relationship between negotiable fate belief and suicidal ideation among rural left-behind children is mediated by coping self-efficacy,and this mediation effect was moderated by gender.This study provides a theoretical explanation for how cultivating the belief in negotiable fate and coping self-efficacy is effective for reducing suicidal ideation of rural left-behind children. 展开更多
关键词 Negotiable fate belief coping self-efficacy suicidal ideation left-behind children gender differences
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Prox1a promotes liver growth and differentiation by repressing cdx1b expression and intestinal fate transition in zebrafish
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作者 Yingying Hu Zhou Luo +8 位作者 Meiwen Wang Zekai Wu Yunxing Liu Zhenchao Cheng Yuhan Sun Jing-Wei Xiong Xiangjun Tong Zuoyan Zhu Bo Zhang 《Journal of Genetics and Genomics》 2025年第1期66-77,共12页
The liver is a key endoderm-derived multifunctional organ within the digestive system.Prospero homeobox 1(Prox1)is an essential transcription factor for liver development,but its specific function is not well understo... The liver is a key endoderm-derived multifunctional organ within the digestive system.Prospero homeobox 1(Prox1)is an essential transcription factor for liver development,but its specific function is not well understood.Here,we show that hepatic development,including the formation of intrahepatic biliary and vascular networks,is severely disrupted in prox1a mutant zebrafish.We find that Prox1a is essential for liver growth and proper differentiation but not required for early hepatic cell fate specification.Intriguingly,prox1a depletion leads to ectopic initiation of a Cdx1b-mediated intestinal program and the formation of intestinal lumen-like structures within the liver.Morpholino knockdown of cdx1b alleviates liver defects in the prox1a mutant zebrafish.Finally,chromatin immunoprecipitation analysis reveals that Prox1a binds directly to the promoter region of cdx1b,thereby repressing its expression.Overall,our findings indicate that Prox1a is required to promote and protect hepatic development by repression of Cdx1b-mediated intestinal cell fate in zebrafish. 展开更多
关键词 ZEBRAFISH Liver development prox1a cdx1b Cell fate transition
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Rheb1 signaling and the fate of pancreatic β cells:Toward a new frontier in diabetes therapy
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作者 Hadi Karimkhani 《World Journal of Diabetes》 2025年第12期235-239,共5页
A recent study in the World Journal of Diabetes by Yang et al explored how Rheb1 signaling influenced pancreaticβcell fate and its potential as a therapeutic target.This invited commentary by a senior diabetes resear... A recent study in the World Journal of Diabetes by Yang et al explored how Rheb1 signaling influenced pancreaticβcell fate and its potential as a therapeutic target.This invited commentary by a senior diabetes researcher discussed the findings of Yang et al in the context of current knowledge onβcell biology,providing critical insight into the role of Rheb1 inβcell survival and function and the prospects for diabetes treatment.Key outcomes of the study were interpreted alongside established literature on Rheb1-mechanistic target of rapamycin signaling in islet cells.Rheb1 emerges as a pivotal regulator ofβcell growth and insulin secretory function,aligning with evidence thatβcell-specific Rheb1 deletion impairsβcell mass and glucose-stimulated insulin secretion.The commentary highlighted how modulating this pathway could preserve or restore theβcell population in diabetes while cautioning about potential off-target effects(e.g.inαcells).Targeting Rheb1 signaling represents a promising new frontier in diabetes therapy to enhanceβcell resilience;however,a balanced approach addressing both its benefits and risks is essential.This letter discussed the scientific implications and future research directions needed to translate Rheb1 modulation into clinical application for diabetes. 展开更多
关键词 Pancreaticβcell fate Rheb1 signaling mTOR pathway Diabetes therapy Βcell survival
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Inhibition of IGF-1Rαaffects the differentiation fate of rat optic cup-derived retinal stem cells to retinal ganglion cells in vitro
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作者 Qi-You Li Xiao-Ling Tan +2 位作者 Hai-Wei Xu Yu-Xiao Zeng Xiao-Yong Huang 《International Journal of Ophthalmology(English edition)》 2025年第4期582-589,共8页
AIM:To explore the impact of insulin-like growth factor-1 receptorα(IGF-1Rα)on the differentiation fate of optic-cupderived retinal stem cells(OC-RSCs)into retinal ganglion cells(RGCs)in vitro.METHODS:OC-RSCs were i... AIM:To explore the impact of insulin-like growth factor-1 receptorα(IGF-1Rα)on the differentiation fate of optic-cupderived retinal stem cells(OC-RSCs)into retinal ganglion cells(RGCs)in vitro.METHODS:OC-RSCs were isolated from optic cups of rats on embryonic day 12.5,and high-purity OC-RSCs were obtained by conditioned culture and passage.Differentiation of OC-RSCs into RGCs under different serum concentrations was examined using flow cytometry,and the serum concentration with high interference with differentiation ratio was selected.Furthermore,the effect of blocking IGF-1Rαon the differentiation of OC-RSCs into RGCs was analyzed through immunocytochemistry and Western blotting.RESULTS:Immunohistochemical analysis revealed IGF-1Rαwas highly expressed in rat embryos at day 12.5.OC-RSCs were isolated and purified,and high-purity OCRSCs were obtained.When 2.5%serum was administered,the ratio of differentiated RGCs(Thy-1.1 positive)decreased significantly,and the results of immunoblotting also confirmed the blockade of IGF-1Rαreduced Thy-1.1 protein expression.CONCLUSION:IGF-1Rαblocking can reduce the differentiation of OC-RSCs into RGCs. 展开更多
关键词 insulin-like growth factor-1 receptorα retinal ganglion cell rat optic cup retinal stem cells differentiation fate
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儒墨而外自为一家——王充“命”论的言说进路与内在逻辑
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作者 李浩 《燕山大学学报(哲学社会科学版)》 2026年第2期8-14,共7页
前人研究常强调王充对先秦儒家“命”论的继承,然诸般史迹象表明,《论衡》虽常常征引孔子、孟子、子夏等人关于“命”的论述,但王充对儒家“命”论的义理层面并不关心,他只是将后者作为话语工具,或利用、或批判以证成己说。王充“命”... 前人研究常强调王充对先秦儒家“命”论的继承,然诸般史迹象表明,《论衡》虽常常征引孔子、孟子、子夏等人关于“命”的论述,但王充对儒家“命”论的义理层面并不关心,他只是将后者作为话语工具,或利用、或批判以证成己说。王充“命”论是对先秦儒学精神的背离。王充极力批判墨家命运学说,连带否定继承墨家“赐夺纪算”观念的汉代“随命”论。王充“命”论是对儒、墨两家学说的刻意立异,表现出强烈的理论建构倾向,在中国思想史、士人心态史上具有典范意义。 展开更多
关键词 命运学说 王充 论衡 儒家 墨家
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《诗经》与古希腊悲剧的战争描写和命运关切
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作者 蒋重跃 《通化师范学院学报》 2026年第1期1-18,共18页
《诗经》和悲剧是古代中希两大文明的艺术瑰宝。它们都有战争描写,但写法迥异。《诗经》重在描写王师威仪、赳赳武夫和征伐夷狄,还有家园思念和民众愁怨,表现的是对天命有德的信心和对天下太平的期盼。古希腊悲剧则热衷于展示城邦陷落... 《诗经》和悲剧是古代中希两大文明的艺术瑰宝。它们都有战争描写,但写法迥异。《诗经》重在描写王师威仪、赳赳武夫和征伐夷狄,还有家园思念和民众愁怨,表现的是对天命有德的信心和对天下太平的期盼。古希腊悲剧则热衷于展示城邦陷落时男子被屠杀、妇女遭凌辱的惨状,以及无所逃避的厄运。为什么会有如此的不同?原因大概有二:其一,天下与城邦两种体制下战争性质以及对战争的态度不同。周人相信天命,以天下为一家,且拥有大一统的封建制、宗法制和五服制,信奉“礼乐征伐自天子出”,王者(天子)之兵上应天命,下顺民心。古希腊世界分散着数以百计的城邦。城邦由公民组成,奉行独立自由原则,城邦间天然地具有敌对关系,希腊城邦之外,还有异族的强大武装,战争随时可能爆发,且胜败无常。输掉战争、丧失自由(公民身份)、惨遭屠杀、身受奴役对于每一位公民都不是危言耸听。总之,一个是天子维护天下秩序,一个是城邦间无端厮杀,这大概是《诗经》与古希腊悲剧战争描写之所以不同的一个客观原因。其二,作者身份、处境、态度不同,写作目的和创作理念相应也不同。周代诗歌是天子和贵族的庙堂音乐作品,由官员创作或采风而来,经学者编订,须体现“天命民心”的为政宗旨,教化人民、团结宗族、协和万邦、安定天下的价值目标,以及“乐而不淫”“哀而不伤”“怨而不怒”的健康心态,被后世概括为“温柔敦厚”的“诗教”原则。古希腊悲剧起源于狄奥尼索斯酒神节日的即兴表演,具有疏泄激情的属性。三大悲剧家都是有民主倾向的阿提卡公民诗人;对于公民来说,观赏悲剧既是权利,又是义务。战争题材悲剧创作所表达的正是公民因战争而产生的恐惧和怜悯。总之,一个是为民而(编)写,一个是为自己而(抒)写;一个重教化,一个任疏泄,这大概就是《诗经》和古希腊悲剧战争描写之所以不同的一个主观原因。 展开更多
关键词 《诗经》 古希腊悲剧 战争 天命 命运:天下 城邦
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Effect of Transplanting Density on Rice Yield,Nitrogen Uptake and ^(15)N-fertilizer Fate 被引量:7
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作者 樊红柱 张鸿 +2 位作者 冯文强 张冀 王昌桃 《Agricultural Science & Technology》 CAS 2012年第5期1037-1039,1054,共4页
[Objective] The aim of this study was investigated the rice yield, nitrogen uptake and ^15-fertilizer fate at different transplanting density to provide scientific ba- sis for improving the yield of rice and applying ... [Objective] The aim of this study was investigated the rice yield, nitrogen uptake and ^15-fertilizer fate at different transplanting density to provide scientific ba- sis for improving the yield of rice and applying reasonably fertilizer. [Method] A field experiment was carried out to study the effect of different transplanting density on rice yield, nitrogen (N) absorption, sources of N uptake by rice and the N balance in the plant-soil systems by using ^15-labelled urea. [Result] There were no significant differences in rice yields and total N uptakes by rice between treatments 30 cm × 30 cm and 40 cm × 40 cm, but the yield of rice and total N absorption in the two treatments were remarkably higher than those in 50 cm × 50 cm treatment. The amounts of total N uptake by rice were in the range of 112.3-162.7 kg/hm2 in the three transplanting densities. The result showed that about 1/3 of the total N uptake by rice was supplied by application fertilizer and the other 2/3 was obtained from the soil N pool. The ^15N-labelled urea absorbed by rice, residual in soil and lost accounted for 16.3%-26.1%, 17.0%-20.9% and 53.0%-66.7% of the total fertilizer, respectively. A great deal of ^15N-labelled urea was lost during the rice growing season. [Conclusion] Considering the rice yield and environmental protection, the transplanting density of 30 cm×30 cm was recommended in the hilly area of Sichuan basin in the southwest China. 展开更多
关键词 Rice yield Nitrogen uptake and balance ^15N-labeled urea ^15N fate Transplanting density
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沉默FATE/BJ-HCC-2基因的表达对肝癌细胞迁移及侵袭的影响 被引量:1
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作者 葛丽丽 朴军颜 +2 位作者 杨小昂 尹艳慧 张毓 《郑州大学学报(医学版)》 CAS 北大核心 2015年第6期805-809,共5页
目的:研究FATE/BJ-HCC-2基因表达与肝癌细胞迁移及侵袭的关系。方法:体外合成FATE/BJ-HCC-2基因序列特异性小干扰RNA(siRNA),转染肝癌细胞系克隆株5B4,并设非特异性siRNA转染和空白对照组。采用RT-PCR及Western blot方法检测各组细胞中F... 目的:研究FATE/BJ-HCC-2基因表达与肝癌细胞迁移及侵袭的关系。方法:体外合成FATE/BJ-HCC-2基因序列特异性小干扰RNA(siRNA),转染肝癌细胞系克隆株5B4,并设非特异性siRNA转染和空白对照组。采用RT-PCR及Western blot方法检测各组细胞中FATE/BJ-HCC-2 mRNA和蛋白的表达;通过Transwell小室模型检测各组细胞体外迁移及侵袭的能力;激光共聚焦显微镜下观察5B4及空质粒转染的对照细胞(Mock)的骨架结构。结果:各组细胞中FATE/BJ-HCC-2 mRNA和蛋白表达差异有统计学意义(F=15.321,P=0.020),特异性siRNA转染组细胞低于其他2组(P<0.05)。抑制FATE/BJ-HCC-2基因表达后,细胞体外迁移及侵袭的能力降低(F=6.171和10.109,P<0.05)。5B4细胞形态拉长,蝌蚪状,呈现迁移、游走的状态;微丝丰富,形态规则,平行贯穿于细胞全长,细胞膜周围有较多丝状伪足伸出;微管减少,分布不规则。结论:FATE/BJ-HCC-2基因表达促进肝癌细胞的迁移及侵袭。 展开更多
关键词 fate/BJ-HCC-2 RNA干扰 肝癌 转移
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单细胞测序技术在植物体细胞胚胎发生中的研究进展及应用
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作者 翁禹豪 陈新颖 +3 位作者 文野 郝兆东 施季森 陈金慧 《南京林业大学学报(自然科学版)》 北大核心 2026年第1期1-11,共11页
体细胞胚胎发生是植物细胞全能性的体现,在种质资源保存、林木育种及基因编辑等领域具有重要应用价值。由于缺乏通用技术体系,林木体胚发生效率种间差异显著,亟须突破外植体脱分化效率低与体胚成熟率不高的瓶颈。深入解析体胚发生的分... 体细胞胚胎发生是植物细胞全能性的体现,在种质资源保存、林木育种及基因编辑等领域具有重要应用价值。由于缺乏通用技术体系,林木体胚发生效率种间差异显著,亟须突破外植体脱分化效率低与体胚成熟率不高的瓶颈。深入解析体胚发生的分子机制是优化体系、推动体胚技术产业化的关键。单细胞测序技术可以在单细胞水平解析转录组异质性与表观遗传调控动态信息,揭示林木体胚发生过程中分子调控机制和细胞命运转换轨迹,为林木遗传育种提供新视角。然而,木本植物细胞特有的细胞壁结构与组织的复杂性严重制约了该技术的应用。本研究系统综述单细胞测序技术的发展历程、木本植物组织样本制备策略及生物信息分析流程,通过列举龙眼(Dimocarpus longan)、椰子(Cocos nucifera)等典型案例,分析其在林木体胚发生研究中的瓶颈与策略,探讨该技术在细胞命运轨迹解析、激素响应机制及多组学系统研究中的应用潜力,并展望未来技术优化与跨物种数据库建设的路径,为林木体胚发生机制研究提供理论支撑。 展开更多
关键词 林木 单细胞测序 体细胞胚胎发生 细胞命运轨迹解析 激素响应机制 多组学系统
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Fate of ^(15)N Labeled Nitrate and Ammonium Salts Added to an Alpine Meadow in the Qinghai-Xizang Plateau, China 被引量:5
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作者 徐兴良 欧阳华 +1 位作者 裴志永 周才平 《Acta Botanica Sinica》 CSCD 2003年第3期276-281,共6页
To understand the dynamics of added nitrogen (N) in alpine meadow and the role of alpine plants and soil microorganisms in the retention of deposited N, the fate of 15 N labeled nitrate and ammonium salts was... To understand the dynamics of added nitrogen (N) in alpine meadow and the role of alpine plants and soil microorganisms in the retention of deposited N, the fate of 15 N labeled nitrate and ammonium salts was determined in an alpine meadow for two months. Two weeks after 15 N application, total recovery of 15 N from NO - 3_ 15 N was 73.5% while it was 78% from NH + 4_ 15 N. More 15 N was recovered in plants than in soil organic matter or in microbial biomass, irrespective of forms of N added. After one month, 70.6% of added NO - 3_ 15 N and 57.4% of NH + 4_ 15 N were recovered in soils and plants. 15 N recovered in soil organic matter decreased greatly while that recovered in plants varied little, irrespective of the form N. Compared with the results of two weeks after 15 N application, more NO - 3_ 15 N than NH + 4_ 15 N was recovered in microbial biomass. Total recovery was 58.4% (six weeks) and 67% (eight weeks) from NO - 3_ 15 N, and 43.1% and 49% from NH + 4_ 15 N, respectively. Both plants and soil microorganism recovered more NO - 3_ 15 N than NH + 4_ 15 N. But plants recovered more 15 N than soil microorganisms. During the whole experiment plants retained more NO - 3_N and 15 N than soil microorganisms while 15 N recovered in inorganic N pool did not exceed 1% due to lower amount of inorganic N. This indicates that plants play more important roles in the retention of deposited N although microbial biomass can be an important sink for deposited N in early days after N application. 展开更多
关键词 alpine meadow soil microorganisms retention of deposited N percentage of 15 N recovery fate of NO - 3_ 15 N and NH + 4_ 15 N
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pnr与fred协同介导果蝇背板中部SOP细胞发生的双重调控
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作者 宋凯月 张翼飞 +8 位作者 张瑶 龙淑婷 彭建军 孙远东 崔小娟 潘本山 柴语心 王晓霞 陈家慧 《遗传》 北大核心 2026年第1期87-101,共15页
根据“预模式假说(Prepattern Hypothesis)”,黑腹果蝇(Drosophila melanogaster)背部感觉器官前体(sensory organ precursors,SOP)的发育依赖于预模式基因、原神经基因和神经源性基因的依次调控。大多数情况下,单一调控基因的功能失常... 根据“预模式假说(Prepattern Hypothesis)”,黑腹果蝇(Drosophila melanogaster)背部感觉器官前体(sensory organ precursors,SOP)的发育依赖于预模式基因、原神经基因和神经源性基因的依次调控。大多数情况下,单一调控基因的功能失常引起的异位SOP形成,或表现为空间不连续,或仅限于原神经簇内。而fred基因的敲低会造成一种异位SOP发生的新型表型,这些异位SOP在空间上是连续的,且不局限于原神经簇区域。本研究发现,由敲减fred所诱导的异位SOP形成不依赖于原神经簇,表明几乎所有翅成虫盘细胞都具有潜在的神经发生潜力。并且,本研究还发现预模式基因pannier(pnr)与fred协同作用,以两种截然不同的方式调控SOP细胞的命运:一方面,pnr和fred在背板中部对于内源性SOP的形成是必需的;但另一方面,它们在原神经簇外协同抑制SOP发生。本研究结果打破了“预模式假说”中SOP形成依赖于原神经簇形成的论断,为该假说提供了一项重要补充。 展开更多
关键词 fred 神经源性潜力 感觉器官前体 PNR 细胞命运决定
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FATE/BJ-HCC-2基因转染对肿瘤细胞生物学行为的影响
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作者 杨小昂 邵启祥 +3 位作者 钱晓萍 李燕 庞学雯 陈慰峰 《河南医学研究》 CAS 2006年第4期305-311,共7页
目的:观察FATE/BJ-HCC-2基因对肿瘤细胞生物学行为的影响,探讨FATE/BJ-HCC-2与肿瘤进展之间的关系。方法:将FATE/BJ-HCC-2基因转染肝癌细胞系Bel-7402细胞,3H-TdR掺入法和Transwell实验对转染细胞的增殖和侵袭能力进行检测;PCR方法检测... 目的:观察FATE/BJ-HCC-2基因对肿瘤细胞生物学行为的影响,探讨FATE/BJ-HCC-2与肿瘤进展之间的关系。方法:将FATE/BJ-HCC-2基因转染肝癌细胞系Bel-7402细胞,3H-TdR掺入法和Transwell实验对转染细胞的增殖和侵袭能力进行检测;PCR方法检测细胞内的骨桥蛋白(OPN)和整合素连接激酶(ILK)基因的表达水平。结果:细胞增殖实验结果显示FATE/BJ-HCC-2转染肿瘤细胞的3H-TdR掺入值显著高于Mock细胞的掺入值,统计学分析二者差别有显著性意义(P<0.01)。FATE/BJ-HCC-2基因表达促进肝癌细胞系Bel-7402细胞的增殖,并且这种增殖效应可被特异性抗-FATE/BJ-HCC-2抗体所阻断。Transwell实验显示,转染FATE/BJ-HCC-2的细胞,其穿膜数量明显比对照组多,差别有显著的统计学意义(P<0.01)。对肿瘤细胞转移相关的细胞信号分子进行检测发现,骨桥蛋白(OPN)和整合素连接激酶(ILK)基因的表达水平上调。结论:肿瘤细胞获得FATE/BJ-HCC-2基因表达后其增殖和侵袭能力增强,FATE/BJ-HCC-2基因表达可能与肿瘤细胞的转移有一定关系。提示CT抗原的表达不仅仅是肿瘤发生中的伴随产物,它可能在肿瘤的发生发展过程中起到一定作用。 展开更多
关键词 CT抗原 fate/BJ-HCC-2 生物学功能 基因转染
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从单个体细胞到全能胚胎:细胞命运的重编程之旅
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作者 李子娟 徐麟 《植物学报》 北大核心 2026年第1期9-14,共6页
植物体细胞胚胎发生是体细胞通过细胞命运重编程再现完整胚胎发育程序、实现全能性的典型过程,并已成为植物生物技术中濒危物种繁殖与转基因作物培育的重要工具。然而,该过程中确切的细胞起源与驱动重编程的分子机制仍不完全清楚。近期... 植物体细胞胚胎发生是体细胞通过细胞命运重编程再现完整胚胎发育程序、实现全能性的典型过程,并已成为植物生物技术中濒危物种繁殖与转基因作物培育的重要工具。然而,该过程中确切的细胞起源与驱动重编程的分子机制仍不完全清楚。近期一项研究表明,LEC2-SPCH基因模块可通过协同作用,局部激活生长素的生物合成,引导子叶表皮气孔谱系前体细胞发生细胞命运转变,进而发育成为体细胞胚。这项研究成果不仅完整捕捉到单个植物体细胞发育成为体细胞胚的全过程,还为解析体细胞重编程提供了重要证据。基于这些发现,该文综述了体细胞胚胎发生过程中细胞命运重编程的调控机制,重点探讨了生长素信号与表观遗传重塑在其中的协同作用,并展望了利用关键重编程因子改良作物再生体系的潜力与未来研究方向。 展开更多
关键词 细胞命运重编程 体细胞胚发生 细胞全能性 表观遗传
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新污染物环境归趋模拟研究的文献计量学分析
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作者 商美琪 董建玮 谢晖 《南京师大学报(自然科学版)》 北大核心 2026年第2期120-131,共12页
新污染物因来源广泛、环境行为复杂及潜在高风险,已成为全球环境科学研究的前沿热点,环境归趋模拟是揭示其环境行为与生态风险的重要方法.本研究基于2001—2025年Web of Science核心合集数据库中的相关文献,采用CiteSpace与VOSviewer两... 新污染物因来源广泛、环境行为复杂及潜在高风险,已成为全球环境科学研究的前沿热点,环境归趋模拟是揭示其环境行为与生态风险的重要方法.本研究基于2001—2025年Web of Science核心合集数据库中的相关文献,采用CiteSpace与VOSviewer两种文献计量与可视化分析工具,对新污染物环境归趋模拟研究进行了系统梳理.结果表明:该领域经历了起步、稳步发展与快速增长3个阶段,中国在发文数量与国际合作中均处于主导地位;研究主题主要集中于新污染物环境归趋建模、环境行为驱动因素、污染源识别与模拟分析、气候变化影响及风险评估方向;研究热点逐步由宏观归趋分析向微观机制解析与区域风险评估转变,并形成以物理模型、化学模型、生物模型、统计模型和综合模型为主的多元建模体系.未来研究应加强多尺度、多介质与多过程模型的耦合集成,以提升复杂环境系统中新污染物归趋行为的预测能力,并为构建全球适用的风险管控框架与政策制定提供坚实支撑.相较以往多侧重于新污染物环境赋存与管理的综述,本文聚焦于环境归趋模拟方法,系统量化梳理了该领域的知识结构与演化趋势,突出了模拟研究在新污染物研究方法体系与实际应用中的关键作用. 展开更多
关键词 新污染物 环境归趋 建模方法 文献计量 趋势演变
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成熟的种子到哪里去了?——评述“Seed Fates:Seed predation,Seed Dispersal and Seedling Establishment”一书
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作者 肖治术 《植物生态学报》 CAS CSCD 北大核心 2005年第3期519-519,共1页
关键词 《Seed fates: SEED predation Seed Dispersal and SEEDLING Establishment》 书评 食果动物 种子扩散 CAB International Publishing出版社
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Posterior enhancer(p-Enh)maintains early neuromesodermal progenitors bi-potency during gastrulation
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作者 Panpan Mi Yingying Chen +7 位作者 Fengxiang Tan Penglei Shen Yun Yang Mingzhu Wen Yun Qian Jichang Wang Naihe Jing Xianfa Yang 《Cell Regeneration》 2026年第1期69-85,共17页
Vertebrate axis patterning requires precise control of the differentiation of neuromesodermal progenitors(NMPs),which generate spinal cord(SC)and presomitic mesoderm(PSM).Previously,we identified a gastrula-premarked ... Vertebrate axis patterning requires precise control of the differentiation of neuromesodermal progenitors(NMPs),which generate spinal cord(SC)and presomitic mesoderm(PSM).Previously,we identified a gastrula-premarked posterior enhancer(p-Enh)that is essential for posterior tissue development by regulating somite and SC in organogenetic embryos,while its role in early NMPs cells remains elusive.Here,using a highly efficient in vitro differentiation system,we found that the genetic removal of p-Enh leads to the aberrantly up-regulated PSM-related genes during both PSM and SC differentiation.Time-resolved transcriptomic analysis and experimental characterization revealed the activated PSM transcriptomic signature arose from disorganized NMPs composition,with an over-representation of the T^(high)SOX2^(low)NMPs subtype.Besides,through a newly developed bioinformatic tool,ST-Pheno,which effectively bridges the in vitro samples to in vivo embryonic phenotypes within spatiotemporal context,we determined that the over-produced T^(high)SOX2^(low)NMPs subtype is predominantly enriched in the anterior primitive streak and adjacent mesoderm region at E7.5,which may disrupt the proper development of NMPs towards prospective PSM and SC,ultimately leading to the posterior development failure.In summary,this study demonstrates a critical role of p-Enh in regulating NMPs subtype composition,which will broaden the molecular understanding of mammalian embryogenesis. 展开更多
关键词 GASTRULATION Neuromesodermal progenitors ENHANCER Cell fate determination ST-Pheno
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FATE/BJ-HCC-2基因表达促进细胞增殖及肿瘤形成 被引量:2
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作者 闫萌 王巍 +3 位作者 杨小昂 张毓 尹艳慧 陈慰峰 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2008年第8期748-754,共7页
FATE/BJ-HCC-2是本实验室鉴定的一个新的肿瘤-睾丸抗原基因,定位于Xq28染色体.为探讨FATE/BJ-HCC-2对细胞生物学行为的影响及裸鼠体内肿瘤形成能力的改变,分别采用脂质体转染真核表达载体及逆转录病毒感染两种方式,获得了FATE/BJ-HCC-2... FATE/BJ-HCC-2是本实验室鉴定的一个新的肿瘤-睾丸抗原基因,定位于Xq28染色体.为探讨FATE/BJ-HCC-2对细胞生物学行为的影响及裸鼠体内肿瘤形成能力的改变,分别采用脂质体转染真核表达载体及逆转录病毒感染两种方式,获得了FATE/BJ-HCC-2表达的Bel-7402单克隆细胞株及NIH-3T3细胞克隆,并通过RT-PCR和Western印迹在基因和蛋白水平鉴定了FATE/BJ-HCC-2表达情况.通过3H-TdR参入法,检测细胞的增殖能力;通过稀释铺板集落形成率测定和软琼脂集落形成实验,检测细胞的集落形成能力;通过裸鼠体内细胞注射成瘤,检测细胞成瘤性和肿瘤生长速度.结果表明,FATE/BJ-HCC-2基因表达能明显提高细胞体外增殖、克隆形成能力和成瘤性.提示其对肿瘤的发生发展起到促进作用. 展开更多
关键词 fate/BJ-HCC-2 细胞增殖 克隆形成能力 致瘤性
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