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Phosphorus acquisition,translocation,and redistribution in maize 被引量:2
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作者 Hui-Ling Guo Meng-Zhi Tian +1 位作者 Xian Ri Yi-Fang Chen 《Journal of Genetics and Genomics》 2025年第3期287-296,共10页
Phosphorus(P)is an essential nutrient for crop growth,making it important for maintaining food security as the global population continues to increase.Plants acquire P primarily via the uptake of inorganic phosphate(P... Phosphorus(P)is an essential nutrient for crop growth,making it important for maintaining food security as the global population continues to increase.Plants acquire P primarily via the uptake of inorganic phosphate(Pi)in soil through their roots.Pi,which is usually sequestered in soils,is not easily absorbed by plants and represses plant growth.Plants have developed a series of mechanisms to cope with P deficiency.Moreover,P fertilizer applications are critical for maximizing crop yield.Maize is a major cereal crop cultivated worldwide.Increasing its P-use efficiency is important for optimizing maize production.Over the past two decades,considerable progresses have been achieved in studies aimed at adapting maize varieties to changes in environmental P supply.Here,we present an overview of the morphological,physiological,and molecular mechanisms involved in P acquisition,translocation,and redistribution in maize and combine the advances in Arabidopsis and rice,to better elucidate the progress of P nutrition.Additionally,we summarize the correlation between P and abiotic stress responses.Clarifying the mechanisms relevant to improving P absorption and use in maize can guide future research on sustainable agriculture. 展开更多
关键词 Plant nutrient Phosphorus acquisition Phosphorus translocation Phosphorus-use efficiency Corn yield
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Basal application combined with topdressing and foliar application of silicon and selenium fertilizers reduces soil cadmium and lead bioavailability and their translocation to brown rice 被引量:1
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作者 Jingyi HU Ronghao TAO +3 位作者 Xinyun XIE Hongjuan LU Xiaojun SHI Wenling YE 《Pedosphere》 2025年第4期667-677,共11页
Soil and foliar applications of silicon(Si)and selenium(Se)fertilizers can inhibit the transfer of heavy metals from the soil to crops.However,it remains unclear how Si and Se affect the bioavailability of cadmium(Cd)... Soil and foliar applications of silicon(Si)and selenium(Se)fertilizers can inhibit the transfer of heavy metals from the soil to crops.However,it remains unclear how Si and Se affect the bioavailability of cadmium(Cd)and lead(Pb)in soil and thereby their transfer to rice in Cd and Pb-polluted fields.In this study,seven treatments were set up in a field experiment conducted in a nonferrous metal mining area in Tongling City,Anhui Province,China:no Si/Se fertilization control(CK),basal Si/Se fertilization(Si-1/Se-1),basal and topdressing Si/Se fertilization(Si-2/Se-2),and basal,topdressing,and foliar Si/Se fertilization(Si-3/Se-3).The results indicated that compared to CK,rice yield increased by 3.94%-14.56%in the other treatments,with the most significant increase observed in Si-3 and Se-3.Additionally,the Cd content in brown rice decreased by 15.42%-51.55%,while Pb content decreased by 16.49%-47.18%.In all treatments except Si-1,both metal contents decreased to below the limits specified in China's food safety standard(GB 2762-2022).Furthermore,they impeded the translocation of these metals to the brown rice,thereby effectively diminishing metal accumulation in rice grain.The effect of Se fertilizer was better than Si fertilizer in decreasing the bioconcentration factors of Cd and Pb and inhibiting their translocation to brown rice.At the same time,the applications of Si and Se increased the Si and Se contents of rice aboveground parts,respectively,and the Se content of brown rice in Se-3 increased by 77.56%,meeting the Se enrichment standard(GB/T 22499-2008).The contents of diethylenetriamine pentaacetic acid-extractable Cd and Pb in soil decreased in all Si/Se treatments by 25.53%and 22.37%in Se-3,respectively.All Si/Se treatments reduced the acid-exchangeable and reducible Cd and Pb in soil and transformed them into the more stable oxidizable and residual fractions.This study revealed that the bioavailability of Cd and Pb in soil and their translocation to brown rice were significantly reduced by the basal application combined with topdressing and foliar application of Si and Se fertilizers. 展开更多
关键词 bioconcentration factor heavy metal fractionation heavy metal pollution husk metal mining translocation factor
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Prenatal diagnosis of balanced translocation from three families:Six case reports
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作者 Xun Kan Yu-Xin Xie +6 位作者 Lan Yao Lu-Yao Wang Yu-Xin Xia Jian-Qiao Sun Ming-Lei Bian Liang Yu Ying-Li Lu 《World Journal of Clinical Cases》 2025年第20期35-41,共7页
BACKGROUND Carriers of chromosomal balanced translocations are often physically healthy with no obvious developmental problems.However,potential chromosomal imbalance in their gametes can lead to implantation failure,... BACKGROUND Carriers of chromosomal balanced translocations are often physically healthy with no obvious developmental problems.However,potential chromosomal imbalance in their gametes can lead to implantation failure,miscarriage,or the birth of a child with a chromosomal abnormality.CASE SUMMARY We report six cases of chromosomal translocations involving three families,including the specific Robertson(Roche)translocation.Case 1:The karyotype of the proband was 46,XX,t(18;19)(q22;p12).Case 2:Interventional prenatal diagnosis at 18 weeks of gestation confirmed that the karyotype of the fetus was 46,XY,t(18;19)(q22;p12).Case 3:The karyotype of the proband was 46,XY,t(5;18)(p13;p11).Case 4:Interventional prenatal diagnosis at 14+6 weeks confirmed that the karyotype of the fetus was 46,XX,der(18)t(5;18)(p13;p11)pat.Case 5:The karyotype of the proband was 45,XY,der(14;22)(q10;q10).Case 6:Interventional prenatal diagnosis at 19+4 weeks confirmed that the karyotype of the fetus was 45,XX,rob(14;22)(q10;q10).CONCLUSION Carriers of chromosomal translocations have a high risk of adverse pregnancy outcomes,though they can still have normal offspring.This report on six cases of chromosomal translocations from three families could serve as a reference for future prenatal diagnosis of chromosomal translocations and decision-making on whether to continue the pregnancy. 展开更多
关键词 Chromosomal translocation Prenatal diagnosis Balanced translocation Robertson translocation Case report
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Identification of a genomic region controlling broad-spectrum immunity to leaf rust in wheat–Agropyron cristatum 2P translocation lines
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作者 Xiajie Ji Shirui Xu +10 位作者 Zongyao Wang Haiming Han Jinpeng Zhang Shenghui Zhou Baojin Guo Xinming Yang Xiuquan Li Xiaomin Guo Taiguo Liu Lihui Li Weihua Liu 《Journal of Integrative Agriculture》 2025年第5期2015-2018,共4页
Wheat leaf rust,caused by Puccinia triticina(Pt),is one of the most devastating diseases in common wheat(Triticum aestivum L.)and can lead to heavy yield loss(Chai et al.2020).Leaf rust can result in 50%yield loss dur... Wheat leaf rust,caused by Puccinia triticina(Pt),is one of the most devastating diseases in common wheat(Triticum aestivum L.)and can lead to heavy yield loss(Chai et al.2020).Leaf rust can result in 50%yield loss during epidemic years(Huerta-Espino et al.2011;Gebrewahid et al.2020;Kolomiets et al.2021).Breeding varieties resistant to leaf rust have been recognized as the most effective and economical method to mitigate wheat losses caused by Pt.The narrow genetic basis of wheat constrains the number of cultivars resistant to leaf rust(Jin et al.2021). 展开更多
关键词 broad spectrum immunity leaf rustcaused Agropyron cristatum genomic region p translocation lines puccinia triticina pt leaf rust WHEAT
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Global patterns and determinants of erosion-induced soil carbon translocation
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作者 Fangli Wei Lanhui Wang +1 位作者 Lizhi Jia Yuanyuan Huang 《Geography and Sustainability》 2025年第5期93-100,共8页
Soil erosion is a critical process influencing the global carbon cycle.However,erosion-induced carbon changes remain inadequately understood,particularly for soil inorganic carbon(SIC).There is also limited knowledge ... Soil erosion is a critical process influencing the global carbon cycle.However,erosion-induced carbon changes remain inadequately understood,particularly for soil inorganic carbon(SIC).There is also limited knowledge about the factors influencing soil carbon dynamics during erosion processes.Here we quantify the global translocation of soil organic carbon(SOC)and SIC due to soil erosion using data-driven global soil carbon estimates combined with a soil erosion map derived from the Revised Universal Soil Loss Equation(RUSLE)model.Our analysis reveals that global SIC and SOC translocations from soil erosion are 107.1 Tg C yr^(−1)and 898.4 Tg C yr^(−1),respectively.These translocations exhibit distinct patterns across aridity gradients and different biomes and soil types,with SIC translocation increasing while SOC translocation decreasing with aridity.Croplands exhibit significantly higher soil carbon translocation compared to natural vegetation,with SIC translocation being 2.41 times higher and SOC translocation 0.65 times higher than in forests.Topographic features(slope length and steepness)predominantly determine soil carbon translocation during erosion,with steeper and longer slopes exacerbating erosion and subsequent SIC/SOC translocation.Land use change,particularly agricultural practices,is also a critical driver.Our findings provide valuable insights into the factors influencing SIC and SOC translocation,enhancing our understanding of the global patterns and determinants of erosion-induced soil carbon dynamics. 展开更多
关键词 Soil organic carbon Soil inorganiccarbon Soil erosion Soil carbon translocation Soil carbonloss
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Nitrogen uptake and carbon-nitrogen synergistic translocation improve yield and nitrogen use efficiency in the dep1 rice line
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作者 Guohui Li Yan Zhang +3 位作者 Jiwei Xu Changjin Zhu Qiuqian Hu Ke Xu 《Journal of Integrative Agriculture》 2025年第12期4787-4809,共23页
Improving rice yield and nitrogen use efficiency(NUE)are crucial challenges for coordinating food production and environmental health.However,little is known about the physiological mechanisms underlying the synergist... Improving rice yield and nitrogen use efficiency(NUE)are crucial challenges for coordinating food production and environmental health.However,little is known about the physiological mechanisms underlying the synergistic effects of high yield and NUE in rice.Using two near-isogenic rice lines(named DEP1 and dep1),a two-year field experiment was conducted to assess agronomic characteristics and the physiological characteristics of carbon and nitrogen translocation under three nitrogen levels.Compared with DEP1,dep1 had higher grain yield,grain filling percentage,nitrogen(N)uptake,and NUE.More non-structural carbohydrates(NSCs)and N in the stems were translocated to grains during grain filling in dep1 than in DEP1.Furthermore,stem NSCs translocation was significantly positively correlated with grain yield,while stem N translocation was significantly positively correlated with NUE.Key carbon metabolism enzyme activities(α-amylase,β-amylase and sucrose-phosphate synthase in stems,and sucrose synthase,ADP-glucose pyrophosphorylase and starch synthase in grains)and stem sucrose transporter gene(OsSUT1 and OsSWEET13)expression were higher in dep1 than in DEP1.This contributed to high stem NSCs translocation.Higher N translocation in the stems occurred due to the higher expression of OsNPF2.4.Moreover,the higher values of root morphological traits(root dry weight,root surface area,root length and root volume)and structural characteristics(stele diameter,cortical thickness and vessel section area)in dep1 explained its high nitrogen uptake.In addition,higher expression of OsNADH-GOGAT1 and OsGS1.3 promoted the assimilation of ammonium and contributed to higher nitrogen uptake in dep1.The application of N reduced carbon translocation but enhanced N translocation by regulating the corresponding metabolic enzyme activities and gene expression.Overall,these findings highlighted the roles of nitrogen uptake,and carbon and nitrogen translocation from stems as crucial characteristics for synergistically improving yield and NUE in the dep1 rice line. 展开更多
关键词 carbon and nitrogen translocation root characteristics enzyme activity gene expression rice(Oryza sativa L.)
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Reciprocal translocation experiments reveal gut microbiome plasticity and host specificity in a Qinghai-Xizang Plateau lizard
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作者 Wei Yu Jing Yang +6 位作者 Li-Wei Teng Xiao-Long Zhao Ze-Yu Zhu Shuang Cui Wei-Guo Du Zhen-Sheng Liu Zhi-Gao Zeng 《Zoological Research》 2025年第1期139-151,共13页
Animal adaptation to environmental challenges is a complex process involving intricate interactions between the host genotype and gut microbiome composition.The gut microbiome,highly responsive to external environment... Animal adaptation to environmental challenges is a complex process involving intricate interactions between the host genotype and gut microbiome composition.The gut microbiome,highly responsive to external environmental factors,plays a crucial role in host adaptability and may facilitate local adaptation within species.Concurrently,the genetic background of host populations influences gut microbiome composition,highlighting the bidirectional relationship between host and microbiome.Despite this,our understanding of gut microbiome plasticity and its role in host adaptability remains limited,particularly in reptiles.To clarify this issue,we conducted a reciprocal translocation experiment with gravid females of the Qinghai toad-headed lizards(Phrynocephalus vlangalii)between high-altitude(2?600 m a.s.l.)and superhigh-altitude(3?600 m a.s.l.)environments on Dangjin Mountain of the Qinghai-Xizang Plateau,China.One year later,we assessed the phenotypes and gut microbiomes of their offspring.Results revealed significant plasticity in gut microbiome diversity and structure in response to contrasting elevations.Highaltitude conditions increased diversity,and maternal effects appeared to enable high-altitude lizards to maintain elevated diversity when exposed to superhigh-altitude environments.Additionally,superhigh-altitude lizards displayed distinct gut microbiome structures with notable host specificity,potentially linked to their lower growth rates.Overall,these findings underscore the importance of the gut microbiome in facilitating reptilian adaptation to rapid environmental changes across altitudinal gradients.Furthermore,this study provides critical insights into microbial mechanisms underpinning local adaptation and adaptative plasticity,offering a foundation for future research on host-microbiome interactions in evolutionary and ecological contexts. 展开更多
关键词 Gut microbiome PLASTICITY Host specificity Phrynocephalus vlangalii Reciprocal translocated experiment
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瑞马唑仑调控转运蛋白介导胶质母细胞瘤细胞的增殖和侵袭
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作者 任向花 刘欣 +1 位作者 何鑫 李轶聪 《北京生物医学工程》 2026年第1期31-38,共8页
目的评估瑞马唑仑(remimazolam,RM)及转运蛋白(translocator protein,TSPO)对胶质瘤细胞增殖、凋亡和侵袭能力的影响,并初步探讨RM在胶质瘤细胞中的分子机制。方法将胶质瘤细胞系U251暴露于不同浓度的RM,采用Ki67细胞增殖检测实验、流... 目的评估瑞马唑仑(remimazolam,RM)及转运蛋白(translocator protein,TSPO)对胶质瘤细胞增殖、凋亡和侵袭能力的影响,并初步探讨RM在胶质瘤细胞中的分子机制。方法将胶质瘤细胞系U251暴露于不同浓度的RM,采用Ki67细胞增殖检测实验、流式细胞术及Transwell实验评估不同浓度RM对细胞增殖、凋亡和侵袭能力的影响;免疫荧光染色检测胶质瘤组织及癌旁组织中TSPO蛋白的表达;将TSPO-siRNA转染至U251细胞中,qRT-PCR检测其mRNA的表达,CCK-8、流式细胞术及Transwell实验分别检测下调TSPO对细胞增殖、凋亡和侵袭的影响。同时采用CCK-8、流式细胞术及Transwell实验分别检测在RM作用下,下调TSPO对U251细胞增殖、凋亡和侵袭的影响。结果随着RM浓度的增加,U251细胞中U251细胞中Ki67阳性细胞数量逐渐减少(P<0.05),而凋亡比例升高(P<0.05),侵袭细胞数也逐渐减少(P<0.05),具有一定的剂量依赖性;TSPO在胶质瘤组织中的表达水平显著高于癌旁组织(P<0.05);转染TSPO-siRNA后,U251细胞中TSPO mRNA的表达水平降低(P<0.05),细胞的增殖能力降低(P<0.05),凋亡比例升高(P<0.05),侵袭细胞数也显著降低(P<0.05);RM与TSPO-siRNA共同作用后,U251细胞的增殖活力进一步降低(P<0.05),凋亡率显著升高(P<0.05),而侵袭细胞数也进一步降低(P<0.05)。结论RM能够介导TSPO的表达,从而抑制胶质瘤细胞的增殖和侵袭,促进其凋亡。 展开更多
关键词 瑞马唑仑 胶质母细胞瘤 转运蛋白 增殖 侵袭
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Fruit Photosynthesis and Assimilate Translocation and Partitioning: Their Characteristics and Role in Sugar Accumulation in Developing Citrus unshiu Fruit 被引量:12
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作者 陈俊伟 张上隆 +2 位作者 张良诚 赵智中 徐建国 《Acta Botanica Sinica》 CSCD 2002年第2期158-163,共6页
Dynamics of dry- or fresh-weight of fruit, peel photosynthetic rate and chlorophyll content, and the characteristics of translocation and distribution of radiolabelled assimilates from leaf or fruit were examined in d... Dynamics of dry- or fresh-weight of fruit, peel photosynthetic rate and chlorophyll content, and the characteristics of translocation and distribution of radiolabelled assimilates from leaf or fruit were examined in developing satsuma mandarin (Citrus unshiu Marc. cv. Miyagawa wase) fruit from primary stage of fruit enlargement up to fruit full ripe. Change in fruit photosynthetic rate was some what related to the change in the chlorophyll content of peel. Fruit photosynthetic rate markedly declined as chlorophyll degradation occurred in the peel. Before full ripe stage of the fruit, photosynthates produced by a 14C-fed leaf were mainly distributed to juice sacs even during periods when dry matter accumulation in peel was more rapid than that in juice sacs. At the full ripe stage, peel photosynthetic rate approached zero and peel became the major sink of leaf photosynthates. Most of the peel assimilates, however, remained in situ for up to 48 h after feeding 14CO 2 to the fruit, only a small portion being transported to other parts of fruit. The percentage of fruit photosynthates exported decreased with fruit development and ripening, but the peak rate of export to juice sacs amount to as high as 12%. The sugar content and dry weights of peel and juice sacs in shaded fruit were lower than that in the control fruit. These results show that peel assimilate was mainly consumed in peel respiration and growth and thus the dependence on leaf photosynthates decreased. Part of this assimiate was used in sugar accumulation in juice sacs of fruit. 展开更多
关键词 satsuma mandarin fruit photosynthesis PHOTOSYNTHATE translocation partitioning sugar accumulation
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Translocation and Distribution of Imidacloprid in Tobacco with Two Application Methods 被引量:9
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作者 韩毅 金洪石 +4 位作者 郭伟 金江华 李玉娥 陶怡 方松 《Agricultural Science & Technology》 CAS 2017年第2期344-346,376,共4页
[Objective] To compare the translocation and distribution of imidacloprid in tobacco with spray and root irrigation application methods. [Methods] Pot experiment in the greenhouse was carried out, and LC-MSMS was used... [Objective] To compare the translocation and distribution of imidacloprid in tobacco with spray and root irrigation application methods. [Methods] Pot experiment in the greenhouse was carried out, and LC-MSMS was used to determine the con- tent of imidacloprid in different parts of tobacco plants (roots, stems, the upper, middle and lower leaves) at different time. [Results] The imidacloprid could be absorbed by root and could be transported to all parts of the tobacco plant after irrigating root, but the original deposition amount was larger and the transport efficiency was lower after spraying. [Conclusion] The translocation and distribution of imidacloprid by spraying was more uniform and the holding efficiency was better, but imidacloprid with root irrigation could act on leaf directly, and had better readily availability. 展开更多
关键词 TOBACCO IMIDACLOPRID SPRAYING Root irrigation translocation and distribution
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Identification of Triticum aestivum-Haynaldia villosa Translocation Line T6BS·6BL-2VS 被引量:2
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作者 陈全战 张边江 +2 位作者 周峰 吴梅 华春 《Agricultural Science & Technology》 CAS 2008年第4期47-50,共4页
[Objective] The aim of experiment was to provide a new germplasm for wheat breeding by further using desirable genes in 2V chromosome of Haynaldia villosa.[Method] Through hybridization between common wheat(Triticum a... [Objective] The aim of experiment was to provide a new germplasm for wheat breeding by further using desirable genes in 2V chromosome of Haynaldia villosa.[Method] Through hybridization between common wheat(Triticum aestivum)-Haynaldia villosa disomic substitution line and common wheat Nonglin26-3C chromosome of Aegilops triuncialis disomic addition line,the analysis methods such as chromosome C-banding,genomic in situ hybridization and molecular marker technique were comprehensively applied and combined characters investigation.[Result] The wheat-Haynaldia villosa translocation line(T6BS·6BL-2VS)was selected from hybrid progenies to conduct characters investigation,which found some bristles on glume ridge of T6BS·6BL-2VS.[Conclusion] The translocation line induced by gametocidal chromosome was a small segment translocation line and the gene of bristle on glume ridge of Haynaldia villosa was located between the middle and the terminal of 2VS. 展开更多
关键词 Common wheat(Triticum aestivum) Haynaldia villosa translocation C-BANDING Fluorescent in SITU hybridization
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Polymorphisms of CMYA3 Gene in 13/17 Robertsonian Translocation Pigs 被引量:2
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作者 孙泰雷 闫守庆 +4 位作者 柏蒙蒙 侯永刚 吴明明 李戈 孙金海 《Agricultural Science & Technology》 CAS 2010年第3期52-53,67,共3页
[Objective] The aim was to study the polymorphism of CMYA3 gene in the 148 pigs of hybrid offspring of 13/17 Robertsonian translocation pigs [2n = 37,rob (13;17)] intercrossing.[Method] PCR-RFLP method was adopted.[... [Objective] The aim was to study the polymorphism of CMYA3 gene in the 148 pigs of hybrid offspring of 13/17 Robertsonian translocation pigs [2n = 37,rob (13;17)] intercrossing.[Method] PCR-RFLP method was adopted.[Result] A 507 bp fragment of CMYA3 gene was obtained by PCR amplification,and then amplification product by using restriction nuclease Bsh1236Ⅰ was detected by agarose gel electrophoresis.As a result,both alleles (A and B) of the loci were found in the population.The frequencies of allele A and B were 0.699 and 0.301.The genotype frequencies of AA,AB and BB were 0.615,0.169 and 0.216.The frequencies of allele A and genotype AA were significantly higher than allele B and genotype BB in populations.[Conclusion] The study will provide theoretical basis for molecular breeding and marker-assisted selection of 13/17 Robertsonian translocation pigs. 展开更多
关键词 PIG Robertsonian translocation CMYA3 gene PCR-RFLP
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Meiotic Behavior of 1BL/1RS Translocation Chromosome and Alien Chromosome in Two Tri-genera Hybrids 被引量:3
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作者 李义文 李振声 贾旭 《Acta Botanica Sinica》 CSCD 2002年第7期821-826,共6页
The behavior of wheat-rye translocation chromosome and alien chromosome including Thinopyrum and Haynaldia chromosome at meiosis was investigated in two hybrids by fluorescence in situ hybridization (FISH). Misdivisio... The behavior of wheat-rye translocation chromosome and alien chromosome including Thinopyrum and Haynaldia chromosome at meiosis was investigated in two hybrids by fluorescence in situ hybridization (FISH). Misdivision of translocation chromosome at anaphase I and rye chromatin micronucleus at tetrad stage were observed, A plant with one normal 1BL/1RS translocation chromosome and one 1BL/1RS translocation chromosome deleted about 1/3 of rye chromosome arm in length was identified. One plant with wheat-Thinopyrum non-Robertson translocation chromosome was also detected in the F-2 population of Yi4212 x Yi4095. That could be the results of unequal misdivision of wheat-rye 1BL/1RS translocation chromosome and Thinopyrum chromosome during meiosis. No interaction between translocation chromosome and alien chromosome at meiosis was supported by the data of the distribution frequencies of translocation chromosome and Thinopyrum or Haynaldia chromosome in the progeny of two hybrids. The results may be useful to cultivate new germplasms with different length of rye 1R short arm and wheat-alien non-Robertson translocation tines under wheat background. 展开更多
关键词 meiosis chromatin univalent 1BL/1RS translocation chromosome fluorescence in situ hybridization
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基因组Translocation排序问题的改进多项式算法 被引量:7
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作者 朱大铭 马绍汉 《计算机学报》 EI CSCD 北大核心 2002年第2期189-196,共8页
该文给出基因组 Translocation排序问题的一个改进多项式算法 .原算法所用存储空间为 O(n) ,时间复杂度为 O(n3) .文中改进算法仍采用 O(n)存储空间 ,时间复杂度为 O(n2 logn) .具体地 ,将计算 Translocation距离的时间复杂度由 O(n3)... 该文给出基因组 Translocation排序问题的一个改进多项式算法 .原算法所用存储空间为 O(n) ,时间复杂度为 O(n3) .文中改进算法仍采用 O(n)存储空间 ,时间复杂度为 O(n2 logn) .具体地 ,将计算 Translocation距离的时间复杂度由 O(n3)改进为 O(n2 ) ,将计算 Translocation序列的时间复杂度由 O(n3)改进为 O(n2 logn) . 展开更多
关键词 算法 时间复杂度 基因组 交叉排序 多项式算法 计算机
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优化轮耕与施肥模式提升潮土养分有效性和作物生产力
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作者 张帅东 刘超麟 +10 位作者 刘世亮 姜桂英 朱宣霖 张琦 郝博伟 王梦茹 王贝贝 刘芳 柳海涛 介晓磊 杨锦 《植物营养与肥料学报》 北大核心 2026年第1期158-172,共15页
【目的】探究不同轮耕及施肥模式对小麦、玉米光合特性及干物质转运和产量的影响,为筛选豫北潮土区最优田间管理措施提供理论依据。【方法】本研究依托位于河南省原阳县的长期耕作定位试验,该试验始于2016年。试验在秸秆还田的基础上采... 【目的】探究不同轮耕及施肥模式对小麦、玉米光合特性及干物质转运和产量的影响,为筛选豫北潮土区最优田间管理措施提供理论依据。【方法】本研究依托位于河南省原阳县的长期耕作定位试验,该试验始于2016年。试验在秸秆还田的基础上采用双因素裂区设计,其中主区为两个施肥处理:单施化肥(NPK)和配施有机肥(MNPK);副区为耕作方式,以3年为一个轮耕周期,共设4个模式:连续旋耕(R-R-R)、深耕-旋耕-旋耕(D-R-R)、深耕-旋耕-浅旋耕(D-R-S)、深耕-浅旋耕-浅旋耕(D-S-S),共8个处理。在第3个轮耕周期的第2年(2023年6、10月),分析了小麦和玉米主要生育时期的光合参数,调查了开花前和成熟期的干物质量,成熟期取0—20 cm和20—40 cm土层样品,分析了土壤养分含量。【结果】小麦开花期,MNPK+D-S-S处理的小麦净光合速率、气孔导度和蒸腾速率显著高于NPK+R-R-R处理,花后干物质对籽粒的贡献较NPK+R-R-R处理增加了29.6%,产量提高了31.1%。小麦成熟期,8个处理以MNPK+D-S-S提高土壤养分含量的效果最优,其0—20 cm土层土壤有机质、全氮、硝态氮、有效磷含量较NPK+R-R-R处理分别提高了32.3%、30.0%、64.3%、292.4%,土壤容重降低了16.4%,孔隙度提高了32.5%。在玉米季,MNPK+D-R-S处理的土壤养分含量、土壤结构及玉米光合特性显著优于其他处理,其0—20 cm土层土壤有机质、全氮、铵态氮、有效磷含量较NPK+R-R-R处理分别提高了39.7%、36.6%、101.9%、541.8%,土壤容重降低了8.5%,孔隙度提高了21.5%,玉米开花期的净光合速率、气孔导度和蒸腾速率显著提高,花后干物质对籽粒的贡献率增加了8.2%,产量提高了20.0%。【结论】在化肥与有机肥配施下,深耕与浅旋耕或旋耕交替进行可显著改善潮土物理性状,提高土壤养分含量,进而提升小麦、玉米光合特性,增强花后干物质转运与积累效率,提高作物产量,因此,可被推荐为当地适宜的农田管理措施。 展开更多
关键词 耕作模式 施肥模式 土壤养分 光合特性 干物质转运 产量
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SINGLE CELL IMAGING OF BAX TRANSLOCATION DURING APOPTOSIS INDUCED BY PHOTOFRIN-PDT
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作者 FEIFAN ZHOU DA XING WEI R.CHEN 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2009年第2期209-214,共6页
Apoptosis is an important cellular event that plays a key role in the therapy of many diseases.The mechanism of the initiation and regulation of photodynamic therapy(PDT)–induced apoptosis is complex.Our previous stu... Apoptosis is an important cellular event that plays a key role in the therapy of many diseases.The mechanism of the initiation and regulation of photodynamic therapy(PDT)–induced apoptosis is complex.Our previous study found that Photofrin was localized primarily in mitochondria,the primary targets of Photofrin-PDT.The key role of Bax in the mitochondria-mediated apoptosis has been demonstrated in many systems.In order to determine the role of Bax in the mitochondrion-mediated apoptosis induced by Photofrin-PDT,we used the GFP-Bax plasmid to monitor the dynamics of Bax activation after PDT treatment.With laser scanning confocal microscopy,we found that Bax did not translocate from the cytosol to mitochondria when the mitochondrial membrane potential(∆Ψm)disappeared,measured by TMRM.Thus,for Photofrin-PDT,the commitment to cell death is independent of Bax activation. 展开更多
关键词 Photofrin-photodynamic therapy mitochondria-mediated apoptosis BAX activation translocation.
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退役铀矿区铀富集植物的筛选研究
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作者 乔新燕 吴仁杰 +5 位作者 原寒 王欣妮 冯青靓 张超 贡文静 曹少飞 《辐射防护》 北大核心 2026年第1期37-46,共10页
植物修复因其原位修复、易于操作、成本低廉、对环境友好等特点被提出,植物修复技术关键在于筛选适宜的富集植物。通过野外调查与采样、室内盆栽模拟筛选和现场种植实验的方法,对候选植物的铀富集因子(F_(V))、转运因子(f_(tr))等进行排... 植物修复因其原位修复、易于操作、成本低廉、对环境友好等特点被提出,植物修复技术关键在于筛选适宜的富集植物。通过野外调查与采样、室内盆栽模拟筛选和现场种植实验的方法,对候选植物的铀富集因子(F_(V))、转运因子(f_(tr))等进行排序,筛选出铀的富集植物。结果显示,野外调查与采样发现芦苇、苞子草的F_(V)>1,是可用于铀污染严重地区的生态修复潜在植物;盆栽模拟实验筛选到了6种铀富集植物(F_(V)>1),分别是鬼针草、秋葵、牛筋草、龙葵、鸭跖草和黑麦草,反枝苋F_(V)<1,但f_(tr)>1。将筛选出的植物和文献推荐的植物用于现场种植实验,结果表明:牛筋草、苏丹草和芥菜的F_(V)>1,f_(tr)<1,花生的F_(V)<1,f_(tr)>1,是可用于铀植物修复研究的候选者。综合三种方法共筛选到10种放射性核素铀的富集植物(F_(V)>1),分别是芦苇、苞子草、苏丹草、芥菜、鬼针草、秋葵、牛筋草、龙葵、鸭跖草和黑麦草,未来以期通过基因工程、育种及相关农艺管控等技术提高这10种植物和反枝苋、花生的修复潜力。 展开更多
关键词 铀污染 植物修复 植物筛选 富集因子 转运因子
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Ruminal dysbiosis-induced mastitis:new insight into the pathogenesis of mastitis
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作者 Caijun Zhao Xiaochun Sun +3 位作者 Naisheng Zhang Xiaoyu Hu Hongyan Li Yunhe Fu 《Journal of Animal Science and Biotechnology》 2026年第1期42-59,共18页
Mastitis is one of the most significant diseases affecting the development of the dairy industry and has traditionally been associated with pathogenic infections.However,emerging evidence highlights that ruminal micro... Mastitis is one of the most significant diseases affecting the development of the dairy industry and has traditionally been associated with pathogenic infections.However,emerging evidence highlights that ruminal microbial homeostasis also plays a crucial role in the pathogenesis of mastitis.Specifically,cows with mastitis exhibit reduced alpha diversity and altered microbial composition in the rumen.Inducing ruminal dysbiosis through a high-concentrate diet has been shown to trigger mastitis in cows,and transplantation of ruminal microbiota from mastitis-affected cows to recipient mice can induce mastitis in mice.Mechanistically,ruminal dysbiosis increases gastrointestinal inflammation and compromises the integrity of the gastrointestinal barrier,thereby facilitating the translocation of harmful bacterial components,metabolites,and pathobionts into the bloodstream.This disruption impairs blood-milk barrier function,leading to systemic inflammation and the development of mastitis.In this review,we summarize recent advances in understanding how ruminal dysbiosis induces mastitis and explore potential prevention and control strategies targeting the modulation of ruminal microbiota. 展开更多
关键词 Bacterial translocation MASTITIS Metabolic disorder PATHOGENESIS Ruminal microbiota
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西方蜜蜂芳烃受体基因AmAHR和芳烃受体核转运因子基因AmARNT的生物信息学分析、表达模式及功能验证
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作者 许昌辉 张书琦 +5 位作者 杨志臣 梁晴 秦屿杨 李江红 段辛乐 黄少康 《昆虫学报》 北大核心 2026年第1期23-33,共11页
【目的】本研究旨在探究西方蜜蜂Apis mellifera芳烃受体(aryl hydrocarbon receptor,AHR)基因AmAHR和芳烃受体核转运因子(aryl hydrocarbon receptor nuclear translocator,ARNT)基因AmARNT在工蜂生长发育过程和杀虫剂胁迫下的表达模式... 【目的】本研究旨在探究西方蜜蜂Apis mellifera芳烃受体(aryl hydrocarbon receptor,AHR)基因AmAHR和芳烃受体核转运因子(aryl hydrocarbon receptor nuclear translocator,ARNT)基因AmARNT在工蜂生长发育过程和杀虫剂胁迫下的表达模式,为这两个基因的功能研究提供理论参考。【方法】通过基因克隆获得西方蜜蜂AmAHR和AmARNT的编码序列(coding sequence,CDS)全长并进行多物种间的同源序列比对和系统进化树构建。利用qRT-PCR检测AmAHR和AmARNT在西方蜜蜂工蜂不同发育阶段(卵、幼虫、蛹和成蜂)、8日龄成年工蜂组织(触角、咽下腺、前足、中足、后足、翅、中肠、后肠和蛰针,及剔除了上述组织的头、胸和腹)和8日龄工蜂成蜂分别口服杀虫剂高效氯氟氰菊酯(1.25,2.5,5和10 mg/L)、氟胺氰菊酯(30,60,120和240 mg/L)和甲酸(1.25,2.5,5和10 mg/L)后的头中的表达量。【结果】克隆获得的西方蜜蜂AmAHR和AmARNT CDS分别编码885和686个氨基酸,编码蛋白均含有1个螺旋-环-螺旋、2个PAS结构域和1个PAC结构域,属于亲水性胞内蛋白。与西方蜜蜂的AmAHR和AmARNT氨基酸序列高度一致的同源蛋白前23个来源物种均属膜翅目(Hymenoptera),AmAHR和AmARNT分别与蜜蜂属Apis的昆虫相应的AHR和ARNT聚为一支。从卵至成蜂的发育过程中,AmAHR的表达量呈单峰型,以白眼白蛹期的表达量最高,显著高于其他发育阶段的,是卵期表达量的37.86倍;AmARNT的表达量呈双峰型,在卵和3日龄预蛹中表达量最高。AmAHR和AmARNT在蛹期的表达量峰期紧邻,且AmARNT先于AmAHR到达表达量峰值。AmAHR的表达量在8日龄工蜂成蜂触角中最高,是头中表达量的34.08倍,且显著高于其他组织中的表达量。AmANRT在8日龄工蜂成蜂胸中的表达量显著高于其他组织中的表达量,是头中表达量的1.75倍。与对照组相比,8日龄工蜂成蜂饲喂15μL 5 mg/L高效氯氟氰菊酯后,头中AmAHR的表达量显著上调至1.83倍,饲喂30和60 mg/L氟胺氰菊酯后,头中AmAHR的表达量则分别上调至1.63和1.74倍,而饲喂120 mg/L氟胺氰菊酯后,头中AmAHR的表达量仅为对照的0.36倍,表达被抑制;饲喂1.25,2.5和5 mg/L的甲酸后,8日龄工蜂成蜂头中AmAHR的表达量分别上调至4.13,3.61和2.56倍。8日龄工蜂成蜂饲喂2.5,10 mg/L高效氯氟氰菊酯和30,120 mg/L氟胺氰菊酯使AmARNT的表达量显著下降,仅分别为对照的0.69,0.68,0.60和0.34倍,但饲喂2.5 mg/L甲酸使AmARNT的表达量上调至对照组的1.68倍。【结论】西方蜜蜂AmAHR和AmARNT分别与其他昆虫的进化关系较为保守;AmAHR和AmARNT在初化蛹期的表达峰同步,暗示两基因的表达有密切关联,且可能与工蜂预蛹的发育有关。AmAHR和AmARNT在两种菊酯类杀虫剂胁迫下表达趋势相同,而与其对甲酸的响应不同,推测与两类杀虫剂的解毒代谢差异机制相关,本研究为进一步挖掘昆虫AHR和ARNT的功能提供新的理论依据。 展开更多
关键词 西方蜜蜂 芳烃受体 芳烃受体核转运因子 基因克隆 时空表达谱 杀虫剂胁迫
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Effect of Interaction upon Translocation of Confined Polymer Chain Through Nanopore 被引量:1
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作者 王瑶 谢永军 +1 位作者 杨海洋 张兴元 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第3期313-316,I0002,共5页
The effect of the interaction between nanopore and chain monomer on the translocation of a single polymer chain confined in a finite size square through an interacting nanopore to a large space has been studied by two... The effect of the interaction between nanopore and chain monomer on the translocation of a single polymer chain confined in a finite size square through an interacting nanopore to a large space has been studied by two-dimensional bond fluctuation model with Monte Carlo simulation. Results indicate that the free energy barrier before the successful translocation of the chain depends linearly on the chain length as well as the nanopore length for different pore-polymer interaction, and the attractive interaction reduces the free energy barrier, leading to the reduction of the average trapping time. 展开更多
关键词 Monte Carlo simulation Polymer translocation INTERACTION Free energy barrier
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