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Editorial: Effect of root anatomy and apoplastic barrier development on cadmium uptake in rice
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作者 Karen S.Hoy Jagdeesh S.Uppal X.Chris Le 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第5期361-363,共3页
Cadmium (Cd) is a toxic metal with high mobility from soil and known translocation into plants (Song et al., 2015).Because the main source of human exposure to Cd is from food consumption, there has been increased res... Cadmium (Cd) is a toxic metal with high mobility from soil and known translocation into plants (Song et al., 2015).Because the main source of human exposure to Cd is from food consumption, there has been increased research examining Cd uptake in agricultural plants (Li et al., 2014;Rizwan et al., 2016;Song et al., 2015). 展开更多
关键词 Metal contamination Cadmium UPTAKE and TRANSLOCATION RICE CULTIVAR and ROOTS Arsenic lead manganese zinc Water and soil Apoplastic BARRIER
基于不同夏填闲作物及种植密度的设施土壤磷素吸收与淋失阻控研究 预览
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作者 裴志强 卢树昌 +2 位作者 侯琨 张宇 王素君 《环境污染与防治》 CAS CSCD 北大核心 2019年第4期398-401,共4页
设施土壤磷素污染日益严重。选用两种夏填闲作物糯玉米和甜高粱,设计了不同种植密度的6个处理,分别为糯玉米常规密度(NYZ,4.95株/m^2)、糯玉米高等密度(NYG,7.50株/m^2)、糯玉米超高密度(NYC,9.90株/m^2)、甜高粱常规密度(TGZ,6.75株/m... 设施土壤磷素污染日益严重。选用两种夏填闲作物糯玉米和甜高粱,设计了不同种植密度的6个处理,分别为糯玉米常规密度(NYZ,4.95株/m^2)、糯玉米高等密度(NYG,7.50株/m^2)、糯玉米超高密度(NYC,9.90株/m^2)、甜高粱常规密度(TGZ,6.75株/m^2)、甜高粱高等密度(TGG,10.49株/m^2)和甜高粱超高密度(TGC,13.49株/m^2)。结果表明,糯玉米和甜高粱常规密度种植并没有达到饱和,两种填闲作物超高密度种植对其长势并不会有大的影响,甚至可促进作物因对光的竞争而长高,提高单位面积干生物量和品质。随种植密度的增大,两种填闲作物的根部的吸磷量显著减小,地上部位显著增大,TGC的总吸磷量最高。种植夏填闲作物对0~30cm的浅层设施土壤中有效磷和水溶性磷具有良好的淋失阻控效果,以TGC的效果最好。因此,TGC对设施土壤磷素吸收和淋失阻控的效果最好。 展开更多
关键词 夏填闲作物 种植密度 设施土壤 磷素 吸收 淋失阻控
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硅调控土壤-水稻中砷环境行为的研究进展 预览
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作者 刘文菊 《河北农业大学学报》 CAS CSCD 北大核心 2019年第3期1-7,共7页
水稻是典型的湿地植被之一,淹水的生长环境使水稻积累砷的能力强于其他谷类作物,对稻米的安全性构成威胁。淹水稻田土壤溶液中砷的主要存在形态为亚砷酸,其与硅酸为化学类似物,亚砷酸可通过根细胞膜上硅酸的转运通道被吸收,因此,外源添... 水稻是典型的湿地植被之一,淹水的生长环境使水稻积累砷的能力强于其他谷类作物,对稻米的安全性构成威胁。淹水稻田土壤溶液中砷的主要存在形态为亚砷酸,其与硅酸为化学类似物,亚砷酸可通过根细胞膜上硅酸的转运通道被吸收,因此,外源添加硅可以降低水稻对砷的吸收、累积以及稻米中砷的健康风险。本文从土壤中砷的生物地球化学过程,硅对土壤中砷环境行为的影响,水稻对砷的吸收与转运,外源硅对水稻吸收及累积砷的影响等方面进行了综述,并对今后开展的研究进行了探讨。 展开更多
关键词 土壤-水稻体系 吸收 迁移
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沙眼衣原体黏附和入侵宿主机制的研究进展
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作者 郭芫 陈超群 《中国病原生物学杂志》 CSCD 北大核心 2019年第1期114-117,122共5页
沙眼衣原体是一种严格细胞内寄生的病原体,也是最常见的性传播疾病病原体,可感染人类多个系统引起多种疾病而影响人类健康。沙眼衣原体具有独特的发育周期,黏附和入侵宿主细胞是它感染过程中的关键步骤,首先通过与宿主细胞的静电作用达... 沙眼衣原体是一种严格细胞内寄生的病原体,也是最常见的性传播疾病病原体,可感染人类多个系统引起多种疾病而影响人类健康。沙眼衣原体具有独特的发育周期,黏附和入侵宿主细胞是它感染过程中的关键步骤,首先通过与宿主细胞的静电作用达到简单吸附,随后由自身黏附素分子与宿主细胞相应受体结合达到不可逆结合,而后通过分泌毒力因子劫持宿主细胞骨架的必需成分或信号通路内化入胞。病原体和宿主因素共同参与沙眼衣原体黏附和入侵过程,掌握黏附和入侵过程中有关的细菌和宿主因素有望设计针沙眼衣原体的抗菌策略。本文从宿主和病原体两个方面阐述沙眼衣原体黏附和入侵宿主相关机制。 展开更多
关键词 沙眼衣原体 黏附 内化 信号通路 综述 麻疹病毒 核壳蛋白 血凝素 融合蛋白 疫苗
Nitrogen uptake regime regulated by ice melting during austral summer in the Prydz Bay, Antarctica 预览
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作者 Run Zhang Qiang Ma +3 位作者 Min Chen Minfang Zheng Jianping Cao Yusheng Qiu 《海洋学报:英文版》 SCIE CAS CSCD 2019年第8期1-7,共7页
Using a combination of stable isotope(15N) and radionuclide(226Ra) analyses, we examine possible controls on the interactions between melting ice and the uptake of nitrogen in the Prydz Bay during the 2006 austral sum... Using a combination of stable isotope(15N) and radionuclide(226Ra) analyses, we examine possible controls on the interactions between melting ice and the uptake of nitrogen in the Prydz Bay during the 2006 austral summer.We find that specific rates of uptake for nitrate and ammonium correlate positively to their concentrations, thus suggesting a substrate effect. In the study area, we observe that regions along open, oceanic water have high fratios(nitrate uptake/nitrate+ammonium uptake), while areas near the Amery Ice Shelf have significantly low fratios. Further analysis reveals a negative correlation between the f-ratio and the melt water fraction, thus implying that the melting of ice plays an essential role in regulating pelagic N dynamics in the Southern Ocean(SO). Stratification, produced by melting ice, should profoundly affect the efficiency of the SO’s biological pump and consequently affect the concentration of CO2 in the atmosphere. Results presented in this study add information to an already significant base of understanding of the controls on pelagic C and N dynamics in the SO. This provides unique insights for either interpreting past changes in geologic records or for predicting future climate change trends. 展开更多
关键词 nitrogen UPTAKE REGIME ICE MELTING PRYDZ Bay ANTARCTICA
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铵硝营养对水稻氮效率和矿质养分吸收的影响
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作者 陈沂岭 赵学强 +1 位作者 张玲玉 沈仁芳 《土壤》 CAS CSCD 北大核心 2019年第2期243-250,共8页
NH4^+和NO3^-是对植物有效的两种主要无机氮源。水稻一般被认为是偏好NH4+的植物,但是在NO3^-条件下,水稻也能良好地生长。大多数关于水稻铵硝营养的报道是在pH6.0左右的水培条件下开展的,但是对于酸性条件下水稻铵硝营养研究很少。随... NH4^+和NO3^-是对植物有效的两种主要无机氮源。水稻一般被认为是偏好NH4+的植物,但是在NO3^-条件下,水稻也能良好地生长。大多数关于水稻铵硝营养的报道是在pH6.0左右的水培条件下开展的,但是对于酸性条件下水稻铵硝营养研究很少。随着土壤酸化的加重及一些边际酸性土壤被用作水稻种植,研究酸性条件下水稻的铵硝营养具有重要意义。本文采用水培试验,在pH5.0的条件下,通过添加和不添加pH缓冲剂MES(2-(N-吗啡啉)乙磺酸),研究了NH4^+和NO3^-对水稻生长、氮效率和矿质养分(N、P、K、Ca、Mg、Fe、Zn、Cu、Mn)吸收的影响。结果表明,在不添加MES的条件下,水稻地上部生长(株高、叶绿素含量、干重)在NH4^+和NO3^-之间没有显著差异,而添加MES后,NH4^+处理的水稻地上部生长优于NO3^-。不管是否添加MES,NO3^-处理的水稻地下部生长(根长、根表面积和根物质量)优于NH4^+。水稻含氮量和氮利用效率在不同NH4^+和NO3^-处理之间没有显著差异,但是NH4^+处理的水稻氮吸收效率高于NO3^-。与NO3^-相比,NH4^+增加了水稻地上部P和Fe含量,而降低了水稻地上部Ca、Mg、Zn、Cu和Mn含量,对K含量影响较小。上述结果表明,NH4^+有利于改善水稻地上部生长,提高氮吸收效率、地上部P和Fe含量,而NO3^-则有利于水稻发根,提高地上部Ca、Mg、Zn、Cu和Mn含量。 展开更多
关键词 NH4^+ NO3^- MES 矿质养分 吸收
Aspirin inhibits the proliferation of hepatoma cells through controlling GLUT 1-mediated glucose metabolism
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作者 Yun-xia Liu Jin-yan Feng +8 位作者 Ming-ming Sun Bo-wen Liu Guang Yang Ya-nan Bu Man Zhao Tian-jiao Wang Wei-ying Zhang Hong-feng Yuan Xiao-dong Zhang 《中国药理学报:英文版》 SCIE CAS CSCD 2019年第1期122-132,共11页
Aspirin can efficiently inhibit liver cancer growth,but the mechanism is poorly,understood.In this study,we-report that aspirin modulates glucose uptake through downregulating glucose transporter 1 (GLUT1),leading to ... Aspirin can efficiently inhibit liver cancer growth,but the mechanism is poorly,understood.In this study,we-report that aspirin modulates glucose uptake through downregulating glucose transporter 1 (GLUT1),leading to the inhibition of hepatoma cell proliferation.Our data showed that aspirin significantly decreased the levels of reactive oxygen species (ROS)and glucose consumption in hepatoma cells.Interestingly,we identified that GLUT1 and HIF1α could be decreased by aspirin.Mechanically,we demonstrated that the -1008/-780 region was the regulatory element of transcriptional factor NF-κB in GLUT1 promoter by luciferase report gene assays.PDTC,an inhibitor of NF-KB,could suppress the expression of GLUT1 in HepG2 and H7402 cells,: followed by affecting the levels of ROS and glucose consumption.CoCl2-activated HIF1α expression could slightly rescue the GLUT1 expression inhibited by aspirin or PDTC,suggesting that aspirin depressed GLUT1 through targeting NF-κB or NF-κB/HIFla signaling.Moreover,we found that GLUT1 was highly expressed in clinical HCC tissues relating to their paired adjacent normal tissues.Importantly,we observed that high level of GLUT1 was significantly correlated with the poor relapse-free survival of HCC patients by analysis of public data.Functionally,overexpression of GLUT1 blocked the PDTC-induced or aspirin-induced inhibition of glucose metabolism in HepG2 cells.Conversely,aspirin failed to work when GLUT1 was stably knocked down in the cells. Administration of aspirin could depress the growth of hepatoma cells through controlling GLUT1 in vitro and in vivo.Thus,our finding provides new insights into the mechanism by which aspirin depresses liver cancer. 展开更多
关键词 ASPIRIN GLUCOSE UPTAKE GLUT1 NF-κB liver cancer
Cd、Zn交互作用对三七景天根系形态和重金属吸收积累的影响 被引量:1
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作者 郭俊娒 杨俊兴 +6 位作者 杨军 陈同斌 李厚恩 徐铁兵 周小勇 叶勇 于豹 《环境科学》 EI CAS CSCD 北大核心 2019年第1期470-479,共10页
采取水培试验,研究了不同Cd、Zn浓度单一胁迫及其交互作用对三七景天生长、根系形态及Cd、Zn吸收和积累的影响.结果表明,三七景天对Cd、Zn单一胁迫均有较强的耐受性,其根、茎、叶各组织中Cd、Zn含量均随胁迫的增加而增加,且对Cd有较强... 采取水培试验,研究了不同Cd、Zn浓度单一胁迫及其交互作用对三七景天生长、根系形态及Cd、Zn吸收和积累的影响.结果表明,三七景天对Cd、Zn单一胁迫均有较强的耐受性,其根、茎、叶各组织中Cd、Zn含量均随胁迫的增加而增加,且对Cd有较强的富集能力,地上部Cd含量可达133.0 mg·kg^-1.Cd、Zn共同胁迫对三七景天生长的影响大于单一胁迫,而根系对其胁迫更为敏感,在Cd、Zn共同胁迫下其根系长度、表面积、体积和根尖数均显著降低,且对其根尖数的影响最为显著.Zn对三七景天地上部Cd吸收具有"低促高抑"效应,低浓度Zn(10 mg·L^-1)对三七景天地上部Cd吸收有协同作用,促进Cd由根部向地上部转运.而添加Cd则对三七景天Zn吸收具有拮抗作用.Zn/Cd浓度比值对三七景天Cd吸收有显著影响,Zn/Cd比值较低时促进三七景天地上部Cd的积累,而高Zn/Cd比则抑制其Cd的积累.因此,三七景天具有较强的Cd富集能力,可应用于修复Cd污染土壤,而调节生长介质中Cd、Zn比例可促进三七景天对Cd的吸收效率. 展开更多
关键词 三七景天 CD ZN 交互作用 根系形态 吸收
不同浓度镧处理对铅胁迫下玉米生长和铅吸收的影响
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作者 王起凡 郭伟 +4 位作者 常青 潘亮 周昕南 杨亮 李娥 《环境科学》 EI CAS CSCD 北大核心 2019年第1期480-487,共8页
采用温室盆栽试验的方法,研究不同浓度的镧处理(0、50、200和800 mg·kg^-1)对中度铅胁迫下(200 mg·kg^-1)玉米生长、矿质营养元素吸收、C:N:P生态化学计量比及Pb和La吸收的影响,探讨土壤-植物系统中稀土重金属的相互作用,旨... 采用温室盆栽试验的方法,研究不同浓度的镧处理(0、50、200和800 mg·kg^-1)对中度铅胁迫下(200 mg·kg^-1)玉米生长、矿质营养元素吸收、C:N:P生态化学计量比及Pb和La吸收的影响,探讨土壤-植物系统中稀土重金属的相互作用,旨在为稀土矿区稀土重金属复合污染土壤的治理提供基础数据和理论依据.结果表明,随着外源La浓度的增加土壤中乙酸铵-EDTA提取态La的浓度显著增加,而乙酸铵-EDTA提取态Pb的浓度显著降低;玉米地上部干重显著降低了17.90%~81.17%,根冠比显著增加了21.74%~86.96%;随着土壤中La浓度的增加根部P含量显著降低了19.16%~89.68%,La浓度为200 mg·kg^-1和800 mg·kg^-1时,地上部P和N含量分别显著降低了65.51%~91.98%和48.27%~76.58%;随着土壤中La浓度的增加,植株C:P、N:P和植株La浓度显著增加,地上部和根部Pb浓度分别显著增加了52.61%~99.01%和15.99%~44.34%;随着La浓度的升高显著降低了玉米植株K、Ca和Mg的含量.结果初步证明,在稀土-重金属复合污染土壤中,稀土元素的存在加剧了重金属对植物生长的毒害效应及其所引发的生态风险问题,应进一步深入研究稀土对植物吸收重金属的影响及作用机制. 展开更多
关键词 玉米 生长 吸收
Plant-derived phosphocholine facilitates cellular uptake of anti-pulmonary fibrotic HJT-sRNA-m7
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作者 Jianchao Du Zhu Liang +14 位作者 Jiantao Xu Yan Zhao Xiaoyun Li Yanli Zhang Dandan Zhao Ruxuan Chen Yang Liu Trupti Joshi Jiahui Chang Zhiqing Wang Yanxu Zhang Jindong Zhu Qiang Liu Dong Xu Chengyu Jiang 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第3期309-320,共12页
Pulmonary fibrosis,a progressive chronic disease with a high mortality rate,has limited treatment options.Currently,lung transplantation remains the only effective treatment.Here we report that a small RNA,HJT-sRNA-m7... Pulmonary fibrosis,a progressive chronic disease with a high mortality rate,has limited treatment options.Currently,lung transplantation remains the only effective treatment.Here we report that a small RNA,HJT-sRNA-m7,from a Chinese herbal medicine Hong Jing Tian(HJT,RHODIOHAE CRENULATAE RADIX ET RHIZOMA,Rhodiola crenulata)can effectively reduce the expressions of fibrotic hallmark genes and proteins both in alveolar in vitro and in mouse lung tissues in vivo.We also discovered over one hundred oil-soluble chemicals from HJT decoctions,most of which are found in lipid extracts from other Chinese herbals decoctions,including Pu Gong Ying(PGY,TARAXACI HERBA,Taraxacum mongolicum),Chuan Xin Lian(CXL,changed to"ANDROGRAPHIS HERBA,Andrographis paniculata"),and Jin Yin Hua(JYH,lonicera japonica or Honeysuckle).We identified the active component in these decoctions as two forms of phosphocholines,PC(18:0/18:2)and PC(16:0/18:2).These PCs potentially could form liposomes with small RNAs to enter human alveolar and gastric cells.Our experimental results suggest an unprecendent lipid complex route through which botanic small RNA can enter human bodies.Our results provide an innovative treatment strategy for oral delivery of siRNAs as therapeutic medication. 展开更多
关键词 PC CELLULAR UPTAKE anti-fibrotic HJT SRNA
植物对硒的吸收利用及主要农作物硒生物强化研究进展 预览
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作者 李秀启 尹国红 +2 位作者 郝浩浩 贾宝华 牛小沛 《甘肃农业科技》 2019年第4期65-71,共7页
从硒对植物的作用、植物对硒的吸收利用、硒肥的应用效果、主要农作物硒生物强化等方面综述了国内外相关研究进展,并对今后的研究方向进行了展望。
关键词 植物 吸收 作物硒强化
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Tuning of activated sludge in winter based on respirogram profiles under standard and site temperatures
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作者 Zhihua Li Zhenyu Hang +3 位作者 Qian Zhang Shuangshuang Zhang Tianyu Zhang Hanqing Yu 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第5期330-338,共9页
Respirograms of activated sludge OUR xTand OURx20were measured under site(T) and standard(20°C) temperatures, respectively, and the predicted standard temperature respirogram OUR x,cal20was also calculated using ... Respirograms of activated sludge OUR xTand OURx20were measured under site(T) and standard(20°C) temperatures, respectively, and the predicted standard temperature respirogram OUR x,cal20was also calculated using the Arrhenius equation. These respirogram profiles reveal more information than effluent quality. A decrease of OUR x 20is a critical alarm signal for the loss of pollutant removal capacity, and a sudden increase of the predicted value OUR x,cal20is an alarm signal for the unrecoverable deterioration of biomass. The sign of OURx20–OURx,cal20can be used for selection of tuning strategies. For example, a negative value of OURx20–OUR x,cal20indicates that doubling biomass is difficult,thus strategies such as extending the reaction time with limited available biomass is preferred. The findings in this study elucidated the respiration profile of activated sludge under changes of temperature and can be effectively used for the stable operation of Wastewater Treatment Plants under cold temperatures and seasonal variations. 展开更多
关键词 Activated SLUDGE Cold temperature SHOCKING Oxygen UPTAKE rate(OUR) Respirogram SEASONAL variations
Interaction effect of nitrogen form and planting density on plant growth and nutrient uptake in maize seedlings 预览
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作者 WANG Peng WANG Zhang-kui +5 位作者 SUN Xi-chao MU Xiao-huan CHEN Huan CHEN Fan-jun Yuan Li-xing MI Guo-hua 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第5期1120-1129,共10页
High planting density is essential to increasing maize grain yield.However,single plants suffer from insufficient light under high planting density.Ammonium(NH4^+)assimilation consumes less energy converted from radia... High planting density is essential to increasing maize grain yield.However,single plants suffer from insufficient light under high planting density.Ammonium(NH4^+)assimilation consumes less energy converted from radiation than nitrateIt is hypothesized that a mixed NO3^-/NH4^+supply is more important to improving plant growth and population productivity under high vs.low planting density.Maize plants were grown under hydroponic conditions at two planting densities(low density:only).A significant interaction effect was found between planting density and N form on plant biomass.Compared to nitrate only,75/25NO3^-/NH4^+increased per-plant biomass by 44%under low density,but by 81%under high density.Treatment with 75/25NO3^-/NH4^+increased plant ATP,photosynthetic rate,and carbon amount per plant by 31,7,and 44%under low density,respectively,but by 51,23,and 95%under high density.Accordingly,carbon level per plant under 75/25NO3^-/NH4^+was improved,which increased leaf area,specific leaf weight and total root length,especially for high planting density,increased by 57,17 and 63%,respectively.Furthermore,under low density,75/25NO3–/NH4+increased nitrogen uptake rate,while under high density,75/25NO3^-/NH4^+increased nitrogen,phosphorus,copper and iron uptake rates.By increasing energy use efficiency,an optimum NO3^-/NH4^+ratio can improve plant growth and nutrient uptake efficiency,especially under high planting density.In summary,an appropriate supply of NH4^+in addition to nitrate can greatly improve plant growth and promote population productivity of maize under high planting density,and therefore a mixed N form is recommended for high-yielding maize management in the field. 展开更多
关键词 MAIZE PLANTING density NO3^-/NH4^+ ratio carbon NUTRIENT UPTAKE ROOT morphology
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Impacts of Bioinoculants Pseudomonas jesenii MP1 and Rhodococcus qingshengii S10107 on Chickpea (Cicer arietinum L.) Yield and Soil Nitrogen St at us
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作者 Divya JOSHI Ramesh CHANDRA +2 位作者 Deep Chandra SUYAL Saurabh KUMAR Reeta GOEL 《土壤圈:英文版》 SCIE CAS CSCD 2019年第3期388-399,共12页
Cold-adapted bioinoculants are considered as harbingers of sustainable hill agriculture. Therefore, two previously characterized psychrotolerant diazotrophs, Pseudomonas jesenii MP1 and Rhodococcus qingshengii S10107,... Cold-adapted bioinoculants are considered as harbingers of sustainable hill agriculture. Therefore, two previously characterized psychrotolerant diazotrophs, Pseudomonas jesenii MP1 and Rhodococcus qingshengii S10107, were evaluated for their plant growthpromoting potential for chickpea (Cicer arietinum L.) grown under natural field conditions. Comparative analysis of agronomical and biochemical crop parameters revealed the irrelevance of chemical fertilizers for chickpea production;the diazotrophs alone were sufficient to fulfil the crop's nutritional requirement. However, the integrated use of bacterial strains in combination with urea at 20 kg N ha^-1 as urea was being recommended for higher crop yield and better soil nitrogen status. Quantitative polymerase chain reaction (qPCR) and denaturing gradient gel electrophoresis (DGGE)-based soil bacterial dynamics unveiled the persistence of both diazotrophs until the end of the crop maturation period without affecting the native micro-flora. Therefore, these bioinoculants can be explored as natural nitrogen resource, and an additional incentive in their bio-formulation will be a step towards agricultural sustainability. 展开更多
关键词 agricultural sustainability denaturing gradient gel ELECTROPHORESIS (DGGE) HILL agriculture psychrotolerance N fertilizer N fixation N uptake quantitative polymerase chain reaction (qPCR)
旱地休闲期间翻耕及覆盖对小麦氮素吸收、运转的影响 预览
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作者 李光 白文斌 +1 位作者 高志强 任爱霞 《干旱地区农业研究》 CSCD 北大核心 2019年第1期102-107,共6页
立足旱地小麦休闲期降水和生育期用水错位问题,连续两年(2009-2011年)在山西闻喜旱地小麦试验基地进行休闲期耕作和覆盖试验,研究不同时间深翻和不同覆盖方式的蓄保水分效果及水分与小麦植株氮素吸收运转的关系。结果表明:休闲期深翻(... 立足旱地小麦休闲期降水和生育期用水错位问题,连续两年(2009-2011年)在山西闻喜旱地小麦试验基地进行休闲期耕作和覆盖试验,研究不同时间深翻和不同覆盖方式的蓄保水分效果及水分与小麦植株氮素吸收运转的关系。结果表明:休闲期深翻(即麦收后45d或15d深翻),渗水地膜覆盖和液态地膜覆盖较不覆盖可提高播前0~300cm土壤蓄水量,可提高旱地小麦各生育阶段,尤其前中期氮素积累量,且麦收后45d深翻后渗水地膜覆盖效果较好;休闲期深翻,渗水地膜和液态地膜覆盖较不覆盖可提高开花期各器官氮素积累量,尤其是麦收后45d深翻后渗水地膜覆盖处理。渗水地膜条件下,麦收后45d较15d深翻可提高开花期叶片和茎秆氮素积累量,可显著提高颖壳+穗轴氮素积累量,可显著提高开花期各器官氮素对籽粒的贡献率,尤其是叶片和茎秆,从而显著提高籽粒氮积累量、成熟期氮素积累量和籽粒产量,且除开花期各器官氮素对籽粒贡献率外,渗水地膜覆盖较液态地膜覆盖效果好,籽粒氮素积累量达17%,籽粒产量达13%。两年相关分析表明,休闲期深翻渗水地膜覆盖或液态地膜覆盖,降水较少年份的旱地小麦播前3m土壤水分与花前氮素运转关系密切,而降水较多年份与花前氮素运转关系及花后氮素积累关系均较为密切,且与花后氮素更密切。研究表明,休闲期深翻(即麦收后45d深翻)后采用渗水地膜覆盖,有利于旱地麦田蓄积休闲期降水,提高播前3m各土层底墒;有利于小麦各生育阶段氮素吸收积累,尤其前中期;有利于花前氮素向籽粒中运转,尤其叶片和茎秆;有利于籽粒中氮素积累和籽粒产量的提高。 展开更多
关键词 旱地小麦 休闲期 深翻 覆盖 氮素 吸收 运转
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HepG2细胞对丹酚酸B的摄取实验研究
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作者 温金华 刘婧 +2 位作者 黎玉华 吕燕妮 曹力 《中南药学》 CAS 2019年第7期1036-1038,共3页
目的研究丹酚酸B(SAB)在肝癌细胞中的摄取动力学特性。方法首先考察系列浓度SAB对HepG2细胞的毒性反应,确定SAB的安全浓度范围,然后建立UPLC-MS法检测SAB浓度,最后考察时间对HepG2细胞摄取SAB的影响,同时研究系列浓度的SAB作用于HepG2... 目的研究丹酚酸B(SAB)在肝癌细胞中的摄取动力学特性。方法首先考察系列浓度SAB对HepG2细胞的毒性反应,确定SAB的安全浓度范围,然后建立UPLC-MS法检测SAB浓度,最后考察时间对HepG2细胞摄取SAB的影响,同时研究系列浓度的SAB作用于HepG2细胞后其摄取量,推算摄取动力学参数。结果1~128μmol·L^-1浓度的SAB作用24 h对HepG2细胞活力无明显影响;作用20 min后HepG2细胞对SAB的摄取开始趋于饱和;系列浓度的SAB作用HepG2细胞10 min后,细胞摄取SAB的量亦随着SAB浓度增加而增加,摄取动力学参数Vmax和Km分别为(9.59±1.75)ng/(mL·min)和(24.91±8.59)mmol·L^-1。结论HepG2细胞对SAB的摄取与时间及药物浓度相关,但尚不明确是主动摄取还是被动摄取过程。 展开更多
关键词 丹酚酸B HEPG2细胞 摄取
脑靶向脂质体构建及其靶分子Ac4MAN体外结构稳定性研究 预览
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作者 李茹冰 王娜 +3 位作者 刘肖莹 唐淑坤 彭海生 陶海泉 《中国医药导报》 CAS 2019年第11期4-8,共5页
目的构建修饰的Ac4MAN(p-羧基苯-α-D-乙酰甘露糖)脑靶向脂质体,并探讨Ac4MAN结构稳定性。方法将Ac4MAN与猪肝酯酶(PLE)于37℃、pH 7.4条件下孵育,于不同时间点取样;采用高效液相色谱(HPLC)和超高效液相色谱-质谱(UPLC-MS)联用技术对其... 目的构建修饰的Ac4MAN(p-羧基苯-α-D-乙酰甘露糖)脑靶向脂质体,并探讨Ac4MAN结构稳定性。方法将Ac4MAN与猪肝酯酶(PLE)于37℃、pH 7.4条件下孵育,于不同时间点取样;采用高效液相色谱(HPLC)和超高效液相色谱-质谱(UPLC-MS)联用技术对其进行分析。制备Ac4MAN脂质体并对其进行表征,用流式细胞仪检测脑胶质瘤细胞U87摄取Ac4MAN脂质体和Ac4MAN脂质体加PLE的情况。结果 HPLC结果显示,孵育0~3 h,Ac4MAN峰面积从578.4减少到37.9;孵育4~7 h,Ac4MAN峰面积接近于0;孵育0~7 h,生成的MAN(p-氨基苯-α-D-吡喃甘露糖苷)的峰面积从0增长到363.0,表明随孵育时间延长,Ac4MAN逐渐减少,MAN逐渐增多。结论本研究制备的Ac4MAN脂质体粒径约为(120.3±2.0)nm,电位约为(-15.76±1.23)mV。Ac4MAN脂质体中加入酶后,U87细胞对其摄取能力有一定的增强。 展开更多
关键词 靶向脂质体 p-羧基苯-α-D-乙酰甘露糖 p-氨基苯-α-D-吡喃甘露糖苷 猪肝酯酶 稳定性 摄取
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Effects of urea enhanced with different weathered coal-derived humic acid components on maize yield and fate of fertilizer nitrogen 预览
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作者 ZHANG Shui-qin YUAN Liang +4 位作者 LI Wei LIN Zhi-an LI Yan-ting HU Shu-wen ZHAO Bing-qiang 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第3期656-666,共11页
Humic acid(HA) is a readily available and low-cost material that is used to enhance crop production and reduce nitrogen(N) loss. However, there is little consensus on the efficacy of different HA components. In the cu... Humic acid(HA) is a readily available and low-cost material that is used to enhance crop production and reduce nitrogen(N) loss. However, there is little consensus on the efficacy of different HA components. In the current study, a soil column experiment was conducted using the 15N tracer technique in Dezhou City, Shandong Province, China, to compare the effects of urea with and without the addition of weathered coal-derived HA components on maize yield and the fate of fertilizerderived N(fertilizer N). The HA components were incorporated into urea by blending different HA components into molten urea to obtain the three different types of HA-enhanced urea(HAU). At harvest, the aboveground dry biomass of plants grown with HAU was enhanced by 11.50–21.33% when compared to that of plants grown with U. More significantly, the grain yields under the HAU treatments were 5.58–18.67% higher than the yield under the urea treatment. These higher yields were due to an increase in the number of kernels per plant rather than the weight of individual kernels. The uptake of fertilizer N under the HAU treatments was also higher than that under the urea treatment by 11.49–29.46%, while the unaccounted N loss decreased by 12.37–30.05%. More fertilizer-derived N was retained in the 0–30 cm soil layer under the HAU treatments than that under the urea treatment, while less N was retained in the 30–90 cm soil layer. The total residual amount of fertilizer N in the soil column, however, did not differ significantly between the treatments. Of the three HAU treatments investigated, the one with an HA fraction derived from extraction with pH values ranging from 6 to 7, resulted in the best improvement in all assessment targets. This is likely due to the abundance of the COO/C–N=O group in this HA component. 展开更多
关键词 HUMIC acid ENHANCED UREA maize ABOVEGROUND dry biomass FERTILIZER N uptake FERTILIZER N residue
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秸秆和猪粪对小麦镉吸收的影响 预览
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作者 陕红 孙宝利 《河南农业科学》 北大核心 2019年第4期14-20,共7页
采用盆栽试验,以黄棕壤和潮土为供试土壤,每种土壤上按照有机碳加入量一致的原则设置5个处理,分别为对照(不添加有机物)、1.1%和2.7%秸秆处理、2%和5%猪粪处理,研究施用秸秆和猪粪对小麦Cd含量、土壤Cd形态、pH值、有机质组成的影响,为... 采用盆栽试验,以黄棕壤和潮土为供试土壤,每种土壤上按照有机碳加入量一致的原则设置5个处理,分别为对照(不添加有机物)、1.1%和2.7%秸秆处理、2%和5%猪粪处理,研究施用秸秆和猪粪对小麦Cd含量、土壤Cd形态、pH值、有机质组成的影响,为利用有机物调控小麦Cd污染提供科学依据。结果表明,施用秸秆和猪粪均可显著降低小麦各部位Cd含量。施用秸秆和猪粪均可促进土壤Cd由活性较强的交换态向其他形态转化。土壤交换态Cd含量与小麦Cd含量呈极显著正相关。秸秆对土壤pH值总体上无显著影响,猪粪可显著降低潮土pH值,增加黄棕壤pH值。施用秸秆和猪粪可使土壤胡敏酸(HA)与富里酸(FA)的比值HA/FA显著升高。土壤HA/FA与交换态Cd含量呈极显著负相关;土壤交换态Cd含量与pH值只有在猪粪施入黄棕壤的处理中呈极显著负相关,在其他处理中均呈正相关。综上,施用秸秆和猪粪均可通过促进土壤Cd形态的转化抑制小麦对Cd的吸收,其机制主要与土壤有机质组成和pH值有关。 展开更多
关键词 秸秆 猪粪 小麦 吸收
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14C-红霉素在水生生物的吸收运转特征 预览
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作者 刘志平 顾鑫 +3 位作者 余凯翔 张素芬 叶庆富 王伟 《核农学报》 CAS CSCD 北大核心 2019年第2期337-345,共9页
为探究红霉素在水环境的生物归趋,本试验采用14C示踪法,建立蝌蚪-浮萍模拟水生生态系统和人工蔬菜水培系统,研究红霉素在蝌蚪、浮萍和食用蔬菜体内的吸收转运特征,并探讨2种不同来源[帕霍基腐殖土(PP)和萨旺泥河(SR)]的水体溶解性有机质... 为探究红霉素在水环境的生物归趋,本试验采用14C示踪法,建立蝌蚪-浮萍模拟水生生态系统和人工蔬菜水培系统,研究红霉素在蝌蚪、浮萍和食用蔬菜体内的吸收转运特征,并探讨2种不同来源[帕霍基腐殖土(PP)和萨旺泥河(SR)]的水体溶解性有机质(DOM)对其生物可利用度的影响。结果表明,20μg·L^-1污染水平下,水体中红霉素能够通过表皮吸收进入水生生物,且其在不同生物中的吸收富集特征存在差异。模拟水生生态系统试验表明,纯水中红霉素能够快速为浮萍吸收富集,并于72 h内达到平衡浓度1.35±0.11 nmol·g^-1(干重),当水体中有DOM存在时,红霉素在浮萍体内的吸收富集受到显著抑制(P<0.05),且SR较PP抑制作用更强;红霉素在蝌蚪体内随着时间推移不断富集,360 h时浓度达到峰值1.20±0.05 nmol·g^-1,SR能够显著抑制蝌蚪对红霉素的吸收;SR对红霉素在浮萍和蝌蚪体内吸收的抑制作用更强,这可能与SR较PP更易与红霉素结合有关。水培蔬菜试验结果表明,水体中红霉素在油菜和生菜体内的富集系数分别为1.65±0.18(地上部)和1.36±0.23 L·kg^-1(地上部),显著低于蝌蚪和浮萍(58.77±0.63和49.58±4.03 L·kg^-1),且可以通过根部吸收运转至水培蔬菜茎叶,但其转运系数均小于1,表明红霉素不易在试验蔬菜体内向上转运;DOM对红霉素在油菜和生菜中的吸收富集无显著影响。本研究为科学评价红霉素的生态安全性提供了理论依据。 展开更多
关键词 14C-示踪 红霉素 溶解性有机质(DOM) 吸收 运转
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