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Development of a FER0.4K SNP array for genomic predication of Fusarium ear rot resistance in maize
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作者 Zhao Wang Haoqiang Zhang +8 位作者 Wenchao Ye Yuchen Han Huan Li Zijian Zhou Chunhui Li Xuecai Zhang Jianan Zhang Jiafa Chen Jianyu Wu 《The Crop Journal》 2025年第3期996-1002,共7页
Fusarium ear rot(FER)caused by Fusarium species severely reduces grain yield and quality of maize.Genome prediction(GP),a promising tool for quantitative trait breeding in plants and animals,uses molecular markers for... Fusarium ear rot(FER)caused by Fusarium species severely reduces grain yield and quality of maize.Genome prediction(GP),a promising tool for quantitative trait breeding in plants and animals,uses molecular markers for capturing quantitative trait loci and predicting the genetic value of candidates for selection.In the present study,different subsets of markers and statistical methods for GP accuracy were tested in diverse inbred populations for FER resistance using a five-fold cross-validation approach.The prediction accuracy increased with an increase in the number of random markers;however,an increase in number beyond 10K did not increase the prediction accuracy.The prediction accuracy of selected markers was higher than that of random markers,and 500–1000 selected markers had the highest prediction accuracy,beyond which it slowly decreased.Although there was no difference among statistical methods when using selected markers at high prediction accuracy,significant differences were observed when using random markers.On this basis,a liquid chip named FER0.4K(liquid chip for genomic prediction of FER)containing 381 SNPs was developed for low-cost,high-throughput genotyping,with a prediction of approximately 0.82.The statistical method of genome prediction was compiled into a web-based,easy-to-use statistical analysis software using the‘‘shiny”package in R.In summary,this study provides a foundation for FER resistance breeding in maize and offers new insights into the genetic improvement of other complex quantitative traits in plants. 展开更多
关键词 Phenotype prediction Molecular breeding Genomic selection MAIZE
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Harnessing chemical communication in plant–microbiome and intra-microbiome interactions
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作者 Hongfu LI Yaxin HU +3 位作者 Siqi CHEN Yusufjon GAFFOROV Mengcen WANG Xiaoyu LIU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第10期923-934,共12页
Chemical communication in plant–microbiome and intra-microbiome interactions weaves a complex network,critically shaping ecosystem stability and agricultural productivity.This non-contact interaction is driven by sma... Chemical communication in plant–microbiome and intra-microbiome interactions weaves a complex network,critically shaping ecosystem stability and agricultural productivity.This non-contact interaction is driven by small-molecule signals that orchestrate crosstalk dynamics and beneficial association.Plants leverage these signals to distinguish between pathogens and beneficial microbes,dynamically modulate immune responses,and secrete exudates to recruit a beneficial microbiome,while microbes in turn influence plant nutrient acquisition and stress resilience.Such bidirectional chemical dialogues underpin nutrient cycling,co-evolution,microbiome assembly,and plant resistance.However,knowledge gaps persist regarding validating the key molecules involved in plant–microbe interactions.Interpreting chemical communication requires multi-omics integration to predict key information,genome editing and click chemistry to verify the function of biomolecules,and artificial intelligence(AI)models to improve resolution and accuracy.This review helps advance the understanding of chemical communication and provides theoretical support for agriculture to cope with food insecurity and climate challenges. 展开更多
关键词 Plant-microbiome interaction Intra-microbiome interaction Chemical communication Click chemistry Genome editing Artificial intelligence(AI)
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土壤温湿度对北京大兴杨树人工林土壤呼吸的影响 被引量:34
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作者 谭炯锐 查同刚 +4 位作者 张志强 孙阁 戴伟 方显瑞 徐枫 《生态环境学报》 CSCD 北大核心 2009年第6期2308-2315,共8页
采用Li-cor-8150土壤呼吸测定系统,对北京大兴杨树人工林(欧美107,Populus×euramericana cv.“74/76”)土壤CO2释放通量、土壤温度和水分进行了为期1年(2007)的定位连续观测,系统研究土壤温度(TS)和土壤含水量(w)对土壤呼... 采用Li-cor-8150土壤呼吸测定系统,对北京大兴杨树人工林(欧美107,Populus×euramericana cv.“74/76”)土壤CO2释放通量、土壤温度和水分进行了为期1年(2007)的定位连续观测,系统研究土壤温度(TS)和土壤含水量(w)对土壤呼吸速率(RS)的影响。结果表明:(1)土壤呼吸速率日变化呈单峰曲线,具有明显的白天高,夜间低的规律。非生长季土壤呼吸速率较低,自5月份土壤呼吸速率上升,8月份达到最大值。(2)土壤温度是影响土壤呼吸速率的主要因素,用指数模型解释全年过程中土壤温度对土壤呼吸速率变化的能力为69%。在低温段(〈0℃)土壤呼吸速率随土壤温度升高而下降,而在土壤温度〉0℃条件下土壤呼吸速率与土壤温度表现为正相关。土壤呼吸速率随土壤含水量上升表现出先升高后降低的趋势,三次方程模拟表明土壤水分的贡献率为33%,而当土壤含水量低于9.5%时,土壤水分的贡献率上升到51%。(3)土壤温、湿度共同作用于土壤呼吸,在不同含水量区间土壤呼吸对土壤温度的响应程度不同:在4%10%土壤含水量范围内,土壤温度与土壤呼吸的指数模型的R2达到0.86,而在土壤水分较高或较低时,其相关系数仅为0.6。土壤温度是影响土壤呼吸速率变化的主导因素,当土壤含水量过低或过高时,土壤温度的主导作用相对减弱,土壤含水量的影响作用相对加强。土壤呼吸的温度敏感性受土壤温度区间和水分区间的综合影响,用指数模型模拟土壤温湿度对土壤呼吸的影响不能很好的模拟土壤湿度的作用,所以单一模型并不是描述土壤温湿度对土壤呼吸的共同影响的最优模型,而多种模型复合的数学模型有待进一步研究。 展开更多
关键词 杨树人工林 土壤呼吸 土壤温度 土壤水分
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流域径流泥沙对多尺度植被变化响应研究进展 被引量:32
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作者 张志强 王盛萍 +1 位作者 孙阁 谢宝元 《生态学报》 CAS CSCD 北大核心 2006年第7期2356-2364,共9页
植被变化与流域水文过程构成一个反馈调节系统,是目前生态水文学研究的重点对象。由于植被自身的生长发育以及受自然因素和人为干扰的作用,植被变化具有多尺度性;由于受流域水文环境的异质性和水文通量的变化性的影响,流域水文过程也同... 植被变化与流域水文过程构成一个反馈调节系统,是目前生态水文学研究的重点对象。由于植被自身的生长发育以及受自然因素和人为干扰的作用,植被变化具有多尺度性;由于受流域水文环境的异质性和水文通量的变化性的影响,流域水文过程也同样具有多尺度性。因此,只有通过对不同尺度生态水文过程分析,才能揭示流域径流泥沙对植被变化的响应机理。从不同时空尺度回顾了植被生长、植被演替、植被分布格局变化、造林以及森林经营措施等对流域径流泥沙影响的主要研究成果;概括了目前研究采用的3种主要方法,即植被变化对坡面水流动力学影响的实验室模拟、坡面尺度和流域尺度野外对比观测实验以及水文生态模型模拟方法;分析了植被变化与径流泥沙响应研究要考虑的尺度问题,从小区尺度上推至流域尺度或区域尺度时应考虑不同的生物物理控制过程。研究认为,要确切理解植被与径流泥沙在不同时空尺度的相互作用,必须以等级生态系统的观点为基础,有效结合生态水文与景观生态的理论,从地质-生态-水文构成的反馈调节入手,系统地理解植被变化与径流泥沙等水分养分之间的联系及反馈机制,建立尺度转换的基础。同时,作为有效的研究工具,今后水文模型的发展应更加注重耦合植被生理生态过程以及景观生态过程,从流域径流泥沙对多尺度植被变化水文响应的过程与机制入手,为植被恢复与重建、改善流域水资源状况和流域生态环境奠定基础。 展开更多
关键词 植被变化 径流泥沙 尺度 水文模型
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黄土高原吕二沟流域侵蚀产沙对土地利用变化的响应 被引量:19
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作者 张志强 王盛萍 +2 位作者 孙阁 张满良 李建劳 《应用生态学报》 CAS CSCD 北大核心 2005年第9期1607-1612,共6页
研究了甘肃天水黄土高原吕二沟流域土地利用变化对流域产沙的影响.结果表明,与1982年相比,1989年该流域林草面积增加约5%,梯田增加2.09%,裸地略有增加,坡耕地减少约1.5%,灌木林略有减少.1998~2000年,在植被覆被增加、陡坡坡耕地减少情... 研究了甘肃天水黄土高原吕二沟流域土地利用变化对流域产沙的影响.结果表明,与1982年相比,1989年该流域林草面积增加约5%,梯田增加2.09%,裸地略有增加,坡耕地减少约1.5%,灌木林略有减少.1998~2000年,在植被覆被增加、陡坡坡耕地减少情况下,随降水增多,其减沙效应明显,如803mm和786 mm降雨条件下,后期较前期(1982~1989年)分别减少85 326 t和52 937 t,降水较少,减沙效应较不明显;从年内含沙量变化来看,后期土地利用的减沙效应主要集中在5~10月,与降水的季节分配一致,各月降水越多,月日均含沙量减少越多,50 mm的月降水月日均含沙量减少6kg·m-3,100mm月降水月日均含沙量减少12kg·m-3.两期土地利用在重现期小于5年时,后期土地利用洪水含沙量较前期稍大,主要由于两期的降水频率分布曲线不一致;若两期降水频率分布曲线一致,则同一频率降水产洪的洪水含沙量后期将小于前期. 展开更多
关键词 土地利用变化 产沙变化 黄土高原
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气候与土地利用变化对流域水资源的影响--以美国北卡罗莱纳州Trent流域为例 被引量:35
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作者 王云琦 齐实 +1 位作者 孙阁 Steve G McNulty 《水科学进展》 EI CAS CSCD 北大核心 2011年第1期51-58,共8页
分布式水文模型PRMS可为气候与土地利用变化对流域水资源影响的研究提供技术和理论支撑。对Trent流域产流过程采用PRMS模型进行模拟检验,结果表明,Nash模型确定性系数达到0.8以上。水文响应单元(HRU)划分尺度减小,可以有效地提高P... 分布式水文模型PRMS可为气候与土地利用变化对流域水资源影响的研究提供技术和理论支撑。对Trent流域产流过程采用PRMS模型进行模拟检验,结果表明,Nash模型确定性系数达到0.8以上。水文响应单元(HRU)划分尺度减小,可以有效地提高PRMS模拟精度达7%左右,划分尺度缩小到71个HRU时,模拟精度不再提高。流域蒸散量和产流量对土地利用和气候变化的敏感程度为:降水量变化〉城市土地利用变化〉气温变化〉农作物和草地(林地)变化;土地利用变化和气候变化对流域产流量的影响大于蒸散量。利用PRMS模型预测Trent流域在未来气候和土地利用同时变化条件下,多年平均蒸散量将增加5.64~201.29mm,产流量有可能增加160mm左右或减少180mm左右。 展开更多
关键词 水资源 降水 温度 土地利用变化 产流量 蒸散量
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锡林郭勒草原不同植被类型的土壤水分特性 被引量:12
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作者 谢静 关文彬 +4 位作者 崔国发 孙阁 Chen Jiquan 王美 綦子达 《东北林业大学学报》 CAS CSCD 北大核心 2009年第1期45-48,共4页
根据压力膜仪测得土壤水分特征曲线,分析了锡林郭勒草原4种植被类型下0-50cm土层的土壤水分特性。结果表明:在中、低吸力段(〈1.5MPa)土壤水吸力与土壤含水量之间存在显著相关关系,且各植被类型不同土层的曲线形状和变化趋势基本... 根据压力膜仪测得土壤水分特征曲线,分析了锡林郭勒草原4种植被类型下0-50cm土层的土壤水分特性。结果表明:在中、低吸力段(〈1.5MPa)土壤水吸力与土壤含水量之间存在显著相关关系,且各植被类型不同土层的曲线形状和变化趋势基本相同。4种植被类型下,土壤有效水含量、土壤持水能力和土壤供水能力呈现出多伦克氏针茅草原〉锡林浩特羊草草原〉东乌珠穆沁大针茅草原〉多伦农田。在多伦克氏针茅草原、锡林浩特羊草草原和多伦农田,随着土层深度的加深,土壤质地逐渐变粗,土壤有效水含量、土壤持水能力和土壤供水能力逐渐减小;在东乌珠穆沁大针茅草原,随着土层深度的加深,土壤机械组成先变粗后变细,在20-30m质地最粗,土壤有效水含量、土壤持水能力和土壤供水能力先减小后增大。 展开更多
关键词 土壤水分 特征曲线 持水能力 有效水 供水能力
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黄土高原防护林建设的恢复生态学与生态水文学基础 被引量:13
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作者 王盛萍 张志强 +1 位作者 张化永 孙阁 《生态学报》 CAS CSCD 北大核心 2010年第9期2475-2483,共9页
以控制土壤侵蚀和提高土地生产力为主要目标的防护林建设是黄土高原植被建设与生态恢复的主体。在对国内外防护林建设研究进行回顾的基础上,从恢复生态学与生态水文学视角探讨了我国西北黄土高原地区防护林建设目标、防护林建设研究尺... 以控制土壤侵蚀和提高土地生产力为主要目标的防护林建设是黄土高原植被建设与生态恢复的主体。在对国内外防护林建设研究进行回顾的基础上,从恢复生态学与生态水文学视角探讨了我国西北黄土高原地区防护林建设目标、防护林建设研究尺度、防护林建设基础理论等,并提出今后黄土高原防护林建设研究方向,其目的在于,通过探讨进一步明确当前黄土高原防护林建设的问题,为该区防护林体系建设提供指导依据。防护林建设除了要达到侵蚀防治等功能的正常发挥外,其终极目标应强调水-沙平衡这一生态水文学目标的实现。防护林建设需要从不同尺度予以理解,除林分尺度的结构优化与功能调控技术以及小流域尺度空间对位配置技术外,区域尺度地带性植被和适宜覆盖率的确定也应为防护林建设的内容。为实现防护林建设的生态水文学目标,防护林建设应遵循恢复生态学中的水分限制因子理论、生态适宜性理论、生物多样性理论以及群落演替理论,这就要求防护林建设总体应以林-水平衡为核心,在实现区域植被地带性及微观尺度适地适树的同时,考虑次生林主要树种的引入,以促进防护林建设生物多样性及群落顺行演替。总体来看,黄土高原防护林建设应基于恢复生态学与生态水文学加强以下研究:(1)针对气候变化,加强防护林建设气候变化适应性评价研究,建立适应性防护林可持续经营管理理论与技术体系;(2)针对立地条件空间异质性,加强高分辨率植被恢复适宜性评价研究,建立定量的植被恢复适地适树适群落理论体系;(3)以恢复生态学原理为指导,加强潜在植被空间分布格局的复原与预测研究,建立近自然防护林建设植被恢复模式;(4)针对全球气候变化与资源性缺水问题,加强基于物理过程分布式生态水文模型的模型模拟研究,为防护林体系建设中植被空间分布、结构组成与规模提供决策依据。 展开更多
关键词 防护林建设 恢复生态学 生态水文学 黄土高原
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永定河沿河沙地杨树人工林生态系统呼吸特征 被引量:8
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作者 方显瑞 张志强 +5 位作者 查同刚 谭炯锐 王小平 陈俊崎 陈吉泉 孙阁 《生态学报》 CAS CSCD 北大核心 2012年第8期2400-2409,共10页
杨树是世界上广泛采用的人工造林树种之一,也是中国人工林面积最大的树种。研究杨树人工林生态系统呼吸(Re)及其分量土壤呼吸(Rs)的时间动态格局以及强度特征,分析两者对环境因子的响应是提高人工林生态系统净生产力和促进固碳减排等人... 杨树是世界上广泛采用的人工造林树种之一,也是中国人工林面积最大的树种。研究杨树人工林生态系统呼吸(Re)及其分量土壤呼吸(Rs)的时间动态格局以及强度特征,分析两者对环境因子的响应是提高人工林生态系统净生产力和促进固碳减排等人工林经营管理中考虑的首要问题。采用开路式涡度相关系统、Licor-8150土壤呼吸测定系统以及小气候测定系统连续测定了位于北京大兴区永定河沿河沙地杨树人工林的生态系统呼吸、土壤呼吸和小气候特征。研究结果表明:(1)2007—2009年该生态系统的Re年总量分别为946.68、863.58、817.30gCm-2a-1,其中Rs年总量分别为642.11、629.29、609.05gCm-2a-1,Rs年总量约占Re年总量的70%;(2)Re和Rs月总量一般在7或者8月份达到最大值,Rs的变化趋势与土壤5cm温度(Ts5)相一致;(3)Ts5是Re和Rs两者的显著影响因子,但Re与空气相对湿度(RH)的相关性最显著。此外,Rs更容易受到Ts5和0—20cm土壤平均体积含水量(vwc)两者耦合效应的限制。 展开更多
关键词 杨树人工林 生态系统呼吸 土壤呼吸 生长季涡度相关法
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基于物理过程分布式流域水文模型尺度依赖性 被引量:8
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作者 王盛萍 张志强 +3 位作者 孙阁 Steve McNulty 张满良 李建牢 《水文》 CSCD 北大核心 2008年第6期1-7,共7页
通过变化基于物理过程分布式参数流域水文模型的单元格大小(Grid size)和时间步长(Time step)研究流域水文过程的尺度依赖性,进而寻求最佳模拟尺度和模拟效果,可以为实现相对准确的流域土地利用变化/植被变化以及气候变异的水文响应预测... 通过变化基于物理过程分布式参数流域水文模型的单元格大小(Grid size)和时间步长(Time step)研究流域水文过程的尺度依赖性,进而寻求最佳模拟尺度和模拟效果,可以为实现相对准确的流域土地利用变化/植被变化以及气候变异的水文响应预测,制定适应性流域管理措施提供科学基础。本文以基于物理过程的分布式水文模型MIKESHE为工具,以位于西北黄土高原甘肃省天水市吕二沟流域的实测次降水-径流为输入对模型进行校正后,采用多尺度检验的方法探讨分析了单元格及步长变化的水文影响。结果表明:单元格变化对峰值及模拟径流总量有影响。单元格从10m增大到200m,模拟峰值及径流总量均增大,分别变化为1.72~8.56m3/s和1.10~3.68×105m3,这主要源于单元格变化引起流域特征变化,10m和200m单元格对应模拟面积分别较原流域面积变化-0.09%和20.57%,河流链接"river link"分别较原沟系长变化27.23%和5.48%。此外,模型中运动波近似方程有限差分像元△x与单元格水流交换总量之间的关系一定程度也解释了单元格变化对模拟结果的影响。分析认为本研究60~100m为较适宜采用的模拟单元格。步长变化引起单位步长内降水强度的变化,从而影响峰值模拟,但对径流总量无影响。步长减小,模拟峰值增高,0.5h步长和24h步长对应模拟峰值分别为2.38m3/s和1.72m3/s。由于各时段观测记录分辨率不一,研究中步长的选择确定具有很大任意性,使得任一既定采用的模拟步长并不适用于另一观测时段,模拟效果不一。 展开更多
关键词 MIKESHE水文模型 尺度变化 水文模拟
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ANSWER2000在小流域土壤侵蚀过程模拟中的应用研究 被引量:32
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作者 牛志明 解明曙 +1 位作者 孙阁 McNulty S G 《水土保持学报》 CSCD 北大核心 2001年第3期56-60,共5页
ANSWERS2 0 0 0是一个用于流域土壤侵蚀过程模拟的分散型物理模型 ,将此模型运用于三峡库区小流域侵蚀产沙、地表径流以及不同土地利用类型水沙分布状况的模拟中。通过两个不同小流域模拟结果的对比 ,采用误差百分比、线性回归以及 Nash... ANSWERS2 0 0 0是一个用于流域土壤侵蚀过程模拟的分散型物理模型 ,将此模型运用于三峡库区小流域侵蚀产沙、地表径流以及不同土地利用类型水沙分布状况的模拟中。通过两个不同小流域模拟结果的对比 ,采用误差百分比、线性回归以及 Nash- Sutcliffe效率 3种方法 ,分析和评价了模型的模拟效果。结果表明 ,模型在应用于我国三峡库区小流域土壤侵蚀模拟时 ,其模拟结果与实测结果具有较高的吻合度 ,模拟结果基本可信。但是 ,对于一些陡坡林地等特殊地类 ,模型的模拟误差较大 ,其模拟精度还有待于进一步提高。 展开更多
关键词 土壤侵蚀模型 小流域 ANSWERS2000
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气候与森林植被变化对水文影响的定量研究进展 被引量:6
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作者 刘士余 孙阁 郭细根 《人民长江》 北大核心 2012年第2期26-29,共4页
如何科学定量地界定气候与森林植被变化对河川径流影响的贡献率,不仅是气候变化影响研究领域中的科学问题,而且也是目前流域管理者所关注和面临的难题。为了给森林植被削洪减灾的作用大小和影响程度提供一个科学的量化依据,在论述森林... 如何科学定量地界定气候与森林植被变化对河川径流影响的贡献率,不仅是气候变化影响研究领域中的科学问题,而且也是目前流域管理者所关注和面临的难题。为了给森林植被削洪减灾的作用大小和影响程度提供一个科学的量化依据,在论述森林植被的水文作用及其局限性的基础上,阐述了气候与森林植被变化对流域水文影响贡献率的国内外研究进展。结果显示,由于研究方法的差异以及研究流域和尺度的不同,研究结果存在较大差异,有关的普遍规律研究仍在探索之中。 展开更多
关键词 气候变化 森林植被变化 流域水文 定量研究
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森林与径流关系——一致性和复杂性 被引量:45
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作者 魏晓华 李文华 +2 位作者 周国逸 刘世荣 孙阁 《自然资源学报》 CSSCI CSCD 北大核心 2005年第5期761-770,共10页
@论文综述国外近一个世纪以来在配对集水区研究方面所取得的结论,从水的自然属性出发,从森林变化对径流(年径流量、洪峰与枯水径流)的影响,径流响应的干扰临界值及水文恢复各方面探讨森林变化与径流关系的一致性与复杂性。森林变化与径... @论文综述国外近一个世纪以来在配对集水区研究方面所取得的结论,从水的自然属性出发,从森林变化对径流(年径流量、洪峰与枯水径流)的影响,径流响应的干扰临界值及水文恢复各方面探讨森林变化与径流关系的一致性与复杂性。森林变化与径流关系的一致性主要表现在由较长时间尺度表达的年径流量上。绝大多数的配对集水区的试验研究表明,采伐森林就会增加年径流量,而在荒地上造林就会减少年径流量。而由较短时间尺度表达的洪峰径流与枯水流量则呈现较大的复杂性和难预估性。综述表明,对径流特别是洪峰与枯水径流的定义及分析方法的不同也是造成森林与径流关系复杂性的重要原因。森林与径流关系的复杂性要求人们在研究及应用其关系时就必须有系统观,必须考虑植被、径流与其它过程(土壤变化、气候变化等)的相互作用。论文还认为尽管配对集水区试验作为一种研究方法为研究者提供了许多可靠的结论,但由于许多研究者只把集水区看作是“黑箱”Q从而对认识森林与径流关系的复杂性有一定的局限性。未来的研究应把配对集水区的试验与其它对过程的研究技术(同位素、GIS等技术)结合起来。 展开更多
关键词 森林变化 年径流量 洪峰径流 枯水流量 水文恢复
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HIV感染和艾滋病的预防策略 被引量:1
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作者 P.Piot B.Schwartlnder +1 位作者 A.C.Gerbase 郝连杰 《德国医学》 CAS 1995年第3期130-131,共2页
流行情况 至1993年底全球向世界卫生组织疫报总共851628例艾滋病,由于疫报延误,发展中国家大部分病例没有确诊、或者基层组织薄弱没有疫报,艾滋病的总数可能比此数字高得多。根据WHO的估计现今全球约有3百万人患艾滋病。各地区受累状况... 流行情况 至1993年底全球向世界卫生组织疫报总共851628例艾滋病,由于疫报延误,发展中国家大部分病例没有确诊、或者基层组织薄弱没有疫报,艾滋病的总数可能比此数字高得多。根据WHO的估计现今全球约有3百万人患艾滋病。各地区受累状况不同,约2/3艾滋病患者在非洲,而向WHO疫报的病人数仅1/3来自非洲。 展开更多
关键词 艾滋病 HIV 人免疫缺陷病毒 感染 预防
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预防保健:围产期妇幼保健中缺失的一环 被引量:6
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作者 Mary-Elizabeth REEVE 《北京大学学报(医学版)》 CAS CSCD 北大核心 2009年第4期383-388,共6页
1 The need to extend and expand the maternal,neonatal and child health (MNCH) continuum to include preconception health The provision of care along the MNCH continuum is currently the core strategy for reducing m... 1 The need to extend and expand the maternal,neonatal and child health (MNCH) continuum to include preconception health The provision of care along the MNCH continuum is currently the core strategy for reducing maternal,neonatal and infant mortality [1-5]. Yet,gaps in the MNCH continuum persist. Reductions in maternal mortality have stagnated in many parts of the world. With the lowering of infant and child mortality,approximately 40% of infant deaths now occur in the neonatal period [6]. Strong scientific evidence indicates that improving women's health before pregnancy would result in better maternal and neonatal health outcomes-specifically,fewer pregnancy complications and a reduction in rates of birth defects,fetal loss,low birth weight and preterm delivery [7]. The WHO estimates that 19% of all maternal deaths are due indirectly to preexisting medical conditions [8]. Furthermore,early prenatal care is too late to prevent many adverse birth outcomes,as organogenesis is completed during the critical first weeks of pregnancy,often before a woman knows that she is pregnant [9]. There is a clear need to strengthen preconception health services. 展开更多
关键词 围生医学 孕前保健 生殖健康服务 健康教育
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Cinnamon extract suppresses experimental colitis through modulation of antigen-presenting cells 被引量:7
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作者 Ho-Keun Kwon Ji-Sun Hwang +8 位作者 Choong-Gu Lee Jae-Seon So Anupama Sahoo Chang-Rok Im Won Kyung Jeon Byoung Seob Ko Sung Haeng Lee Zee Yong Park Sin-Hyeog Im 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第8期976-986,共11页
AIM:To investigate the anti-inflammatory effects of cinnamon extract and elucidate its mechanisms for targeting the function of antigen presenting cells.METHODS:Cinnamon extract was used to treat murine macrophage cel... AIM:To investigate the anti-inflammatory effects of cinnamon extract and elucidate its mechanisms for targeting the function of antigen presenting cells.METHODS:Cinnamon extract was used to treat murine macrophage cell line(Raw 264.7),mouse primary antigen-presenting cells(APCs,MHCII+) and CD11c+dendritic cells to analyze the effects of cinnamon extract on APC function.The mechanisms of action of cinnamon extract on APCs were investigated by analyzing cytokine production,and expression of MHC antigens and co-stimulatory molecules by quantitative real-time PCR and flow cytometry.In addition,the effect of cinnamon extract on antigen presentation capacity and APC-dependent T-cell differentiation were analyzed by [H3]-thymidine incorporation and cytokine analysis,respectively.To confirm the anti-inflammatory effects of cinnamon extract in vivo,cinnamon or PBS was orally administered to mice for 20 d followed by induction of experimental colitis with 2,4,6 trinitrobenzenesulfonic acid.The protective effects of cinnamon extract against experimental colitis were measured by checking clinical symptoms,histological analysis and cytokine expression prof iles in inflamed tissue.RESULTS:Treatment with cinnamon extract inhibited maturation of MHCII+ APCs or CD11c+ dendritic cells(DCs) by suppressing expression of co-stimulatory molecules(B7.1,B7.2,ICOS-L),MHCII and cyclooxygenase(COX)-2.Cinnamon extract induced regulatory DCs(rDCs) that produce low levels of pro-inflammatory cytokines [interleukin(IL)-1β,IL-6,IL-12,interferon(IFN)-γ and tumor necrosis factor(TNF)-α] while expressing high levels of immunoregulatory cytokines(IL-10 and transforming growth factor-β).In addition,rDCs generated by cinnamon extract inhibited APC-dependent T-cell proliferation,and converted CD4+ T cells into IL-10high CD4+ T cells.Furthermore,oral administration of cinnamon extract inhibited development and progression of intestinal colitis by inhibiting expression of COX-2 and pro-inflammatory cytokines(IL-1β,IFN-γ and TNF-α),while enhancing IL-10 levels.CONCLUSION:Our study suggests the potential of cinnamon extract as an anti-inflammatory agent by targeting the generation of regulatory APCs and IL-10+ regulatory T cells. 展开更多
关键词 Cinnamon extract Inflammation CD4 antigen Antigen presenting cells CYCLOOXYGENASE-2 Tumor necrosis factor-α INTERLEUKIN-10 Inflammatory bowel disease
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Redox regulation of fertilisation and the spermatogenic process 被引量:8
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作者 Junichi Fujii Satoshi Tsunoda 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第3期420-423,511,512,共6页
Oxidative stress is one of the major causes of male infertility; it damages spermatogenic cells, the spermatogenic process and sperm function. Recent advances in redox biology have revealed the signalling role of reac... Oxidative stress is one of the major causes of male infertility; it damages spermatogenic cells, the spermatogenic process and sperm function. Recent advances in redox biology have revealed the signalling role of reactive oxygen species (ROS) that are generated by cells. While highly reactive oxidants, such as the hydroxyl radical, exert largely deleterious effects, hydrogen peroxide can feasibly serve as a signal mediator because it is moderately reactive and membrane permeable and because it can oxidize only limited numbers of functional groups of biological molecules. The amino acid side chain most sensitive to oxidation is cysteine sulphydryl, which is commonly involved in the catalysis of some enzymes. Although the reactivity of cysteine sulphhydryl is not very high in ordinary proteins, some phosphatases possess a highly reactive sulphydryl group at their catalytic centre and are thereby oxidatively inactivated by transiently elevated hydrogen peroxide levels after extracellular stimuli and under certain environmental conditions. Peroxiredoxins, in turn, show moderate hydrogen peroxide-reducing activity, and their role in the modulation of ROS-mediated signal transduction in ordinary cells, mediated by protecting phosphatases from oxidative inactivation, has attracted much attention. Although knowledge of the signalling role of ROS in the male reproductive system is limited at present, its significance is becoming a focal issue. Here, we present a review of the emerging signalling role of hydrogen peroxide in testes. 展开更多
关键词 hydrogen peroxide oxidative stress PEROXIREDOXIN signal transduction
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Road induced edge effects on a forest bird community in tropical Asia 被引量:2
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作者 Daphawan Khamcha Richard T.Corlett +3 位作者 Larkin A.Powell Tommaso Savini Antony J.Lynam George A.Gale 《Avian Research》 CSCD 2018年第2期123-135,共13页
Background: Edge effects cause changes in bird community richness, abundance, and/or distribution within a landscape, but the avian guilds most influenced can vary among regions. Although Southeast Asia has the highes... Background: Edge effects cause changes in bird community richness, abundance, and/or distribution within a landscape, but the avian guilds most influenced can vary among regions. Although Southeast Asia has the highest rates of deforestation and projected species loss, and is currently undergoing an explosive growth in road infrastructure, there have been few studies of the effects of forest edges on avian communities in this region.Methods: We examined avian community structure in a dry evergreen forest in northeastern Thailand adjacent to a five-lane highway. We evaluated the richness and abundance of birds in 11 guilds at 24 survey points on three parallel transects perpendicular to the edge. At each point, 10-min surveys were conducted during February-August 2014 and March-August 2015. Vegetation measurements were conducted at 16 of the bird survey points and ambient noise was measured at all 24 survey points.Results: We found a strongly negative response to the forest edge for bark-gleaning, sallying, terrestrial, and understory insectivores and a weakly negative response for arboreal frugivore-insectivores, foliage gleaning insectivores, and raptors. Densities of trees and the percentage canopy cover were higher in the interior, and the ambient noise was lower. In contrast, arboreal nectarivore-insectivores responded positively to the forest edge, where there was a higher vegetation cover in the ground layer, a lower tree density, and a higher level of ambient noise.Conclusion: Planners should avoid road development in forests of high conservation value to reduce impacts on biodiversity. Where avoidance is impossible, a number of potential mitigation methods are available, but more detailed assessments of these are needed before they are applied in this region. 展开更多
关键词 Road edge Avian guilds Dry evergreen forest Thailand
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Natural variation in maize gene ZmSBR1 confers seedling resistance to Fusarium verticillioides 被引量:2
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作者 Yunxia Song Peipei Ma +10 位作者 Jingyang Gao Chaopei Dong Zhao Wang Yifan Luan Jiafa Chen Doudou Sun Pei Jing Xuecai Zhang Weibin Song Zijian Zhou Jianyu Wu 《The Crop Journal》 SCIE CSCD 2024年第3期836-844,共9页
Maize seedling blight caused by Fusarium verticillioides is a widely occurring maize disease,but the genetics and mechanisms of resistance are not well understood.In this study,GWAS performed by MLM and 3VmrMLM identi... Maize seedling blight caused by Fusarium verticillioides is a widely occurring maize disease,but the genetics and mechanisms of resistance are not well understood.In this study,GWAS performed by MLM and 3VmrMLM identified 40 and 20 QTNs,associated with seedling blight resistance.These methods identified 49 and 36 genes,respectively.Functional verification of candidate gene ZmSBR1 identified by both methods showed that the resistance of a mutant line to seedling blight decreased by 0.37 grade points after inoculation with F.verticillioides,compared with the WT.The length of the stem rot lesion caused by F.verticillioides increased by 86%in mutant seedlings,and the relative length of the adult plant stalk rot increased by 35%in mutant plants compared to the wild type after inoculation with Fusarium graminearum.Transcriptome analysis showed that expression of defense-related genes after inoculation was down-regulated in the mutant compared to the wild type,synthesis of secondary metabolites associated with resistance was reduced,and the immune response triggered by PAMP decreased,resulting in decreased resistance of mutant maize seedlings.Candidate gene association analysis showed that most maize inbred lines carried the susceptible haplotype.A functional PCR marker was developed.The results demonstrated that ZmSBR1 conferred resistance to multiple Fusarium diseases at the seedling and adult growth stages and had important application value in breeding. 展开更多
关键词 Seedling blight Stalk rot Multiple disease resistance
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Calibration of SWAT2009 Using Crop Biomass, Evapotranspiration, and Deep Recharge: Calera Watershed in Zacatecas, Mexico Case Study 被引量:1
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作者 Jose R. ávila-Carrasco Francisco Mojarro Dávila +10 位作者 Daniel N. Moriasi Prasanna H. Gowda Carlos Bautista-Capetillo Francisco G. Echavarria-Cháirez Jurgen D. Garbrecht Jean L. Steiner Terry A. Howell Edward T. Kanemasu Alan J. Verser Kevin Wagner Jairo Hernandez 《Journal of Water Resource and Protection》 2012年第7期439-450,共12页
Groundwater is the main source of water in the semi-arid Calera watershed, located in the State of Zacatecas, Mexico. Due to increasing population, rapid industrial growth, and increased irrigation to meet growing foo... Groundwater is the main source of water in the semi-arid Calera watershed, located in the State of Zacatecas, Mexico. Due to increasing population, rapid industrial growth, and increased irrigation to meet growing food demand, groundwater extraction in the Calera watershed are exceeding recharge rates. Therefore, development and evaluation of alter-native water management strategies are needed for sustainable development of the region. The Soil and Water Assessment Tool (SWAT) model was selected for this purpose as it has been used to simulate a wide range of agricultural production, the extensive testing and application in diverse watersheds worldwide, and the potential for future linkage of this model to groundwater models. However, crucial flow data which are commonly used for calibrating hydrologic models are not available in this watershed. This paper describes a novel calibration methodology that uses biomass and water balance approach which has potential for calibration of hydrologic models in ungauged or data-scarce watersheds, which are prevalent in many parts of the world. Estimated long-term annual average actual evapotranspiration (AET), and deep aquifer recharge rates and plant biomass values based on the expert knowledge of researchers and managers in the watershed were used as targets for calibration. The model performance was assessed using the Nash-Sutcliffe effi-ciency coefficient (NSE), coefficient of determination (R2), and percent bias (PBIAS, %) statistics. On average, the calibrated SWAT model yielded annual Nash-Sutcliffe efficiency coefficient values of 0.95, 0.99, and 0.85 for AET, recharge, and biomass, respectively. The coefficient of determination, values for AET, recharge, and biomass were 0.95, 0.94, and 0.99 respectively. The percent bias values of ±2.21%, ±0.18%, and ±0.96% for AET, recharge, and biomass, respectively, indicated that the model reproduced the calibration target values of the three water budget variables within an acceptable value of ± 10.0%. Therefore, it is concluded that the calibrated SWAT model can be used in evaluating alternative water management scenarios for the Calera watershed without further validation. Considering the relative ease in developing calibration data and excellent performance statistics, the calibration methodology proposed in this study may have the potential to be used for ungauged or data-scare agricultural watersheds that are prevalent in many parts of the world. 展开更多
关键词 SWAT Calera WATERSHED Scenarios RECHARGE EVAPOTRANSPIRATION RUNOFF Erosion
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