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肺原发黏液表皮样癌中MAML2基因易位及其诊断、预后意义
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作者 罗东兰 严金海 +5 位作者 葛岩 颜黎栩 陈洁 许洁 骆新兰 刘艳辉 《中华病理学杂志》 CAS CSCD 北大核心 2019年第1期26-30,共5页
目的了解肺原发黏液表皮样癌(MEC)和形态相似的肺腺鳞癌中的MAML2基因易位情况及其对诊断、预后的意义。方法利用组织芯片对2007年至2016年间广东省人民医院诊断的24例肺原发MEC和44例肺腺鳞癌进行MAML2基因易位的荧光原位杂交(FISH)检... 目的了解肺原发黏液表皮样癌(MEC)和形态相似的肺腺鳞癌中的MAML2基因易位情况及其对诊断、预后的意义。方法利用组织芯片对2007年至2016年间广东省人民医院诊断的24例肺原发MEC和44例肺腺鳞癌进行MAML2基因易位的荧光原位杂交(FISH)检测,并进行包括甲状腺转录因子1(TTF1)、NapsinA、细胞角蛋白(CK)5/6、p63、p40、Ki-67等在内的免疫组织化学套餐检测。收集所有临床资料,随访所有的肺原发MEC患者。结果肺原发MEC患者的年龄分布为6~73岁,中位年龄32岁。男女比例为1.4:1.0。肺原发MEC中MAML2基因易位检出率为66.7%(16/24),而所有的肺腺鳞癌中均未检出MAML2基因易位。MAML2基因易位、年轻、组织学低级别与预后好相关。所有肺MEC组织切片均不表达TTF1和NapsinA,特征性的于中间细胞和表皮样细胞区域表达CK5/6、p63和p40。大多数肺原发MECKi-67阳性指数普遍低于10%。而肺腺鳞癌组中,大部分腺癌的成分表达TTF1和NapsinA,鳞癌成分表达CK5/6、p63和p40,表达模式与MEC不同。免疫组织化学套餐的应用鉴别出形态类似于MEC的高度侵袭性ALK阳性的腺癌。结论约2/3的肺原发MEC可检测到MAML2基因易位。MAML2基因发生易位、组织学低级别等因素与预后好相关。套餐式免疫组织化学抗体联合应用,有助于鉴别肺原发MEC和腺鳞癌、形态类似MEC的腺癌。 展开更多
关键词 肺肿瘤 黏液表皮样瘤 易位 遗传 MAML2基因易位
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
磷硒配施对冬小麦幼苗磷硒吸收和转运的影响 预览
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作者 聂兆君 李金峰 +3 位作者 赵鹏 刘世亮 方先芝 刘红恩 《西南农业学报》 CSCD 北大核心 2019年第1期122-127,共6页
【目的】研究磷硒配施对冬小麦幼苗生物量以及磷、硒吸收和转运的影响。【方法】采用改良的霍格兰营养液培养的方式,分别设置3个磷水平(0.31,3.1,31mg/L)和3个硒水平(0,0.1,1mg/L),共9个处理。【结果】中磷(P3.1)和高磷(P31)处理增加小... 【目的】研究磷硒配施对冬小麦幼苗生物量以及磷、硒吸收和转运的影响。【方法】采用改良的霍格兰营养液培养的方式,分别设置3个磷水平(0.31,3.1,31mg/L)和3个硒水平(0,0.1,1mg/L),共9个处理。【结果】中磷(P3.1)和高磷(P31)处理增加小麦幼苗地上部生物量,降低小麦幼苗根冠比;2个施硒处理(Se0.1和Se1)则降低小麦幼苗地上部生物量,增加小麦幼苗根冠比,磷硒配施有利于根系的生长发育。施硒(Se0.1和Se1)抑制冬小麦磷向地上部的转运和累积,却在高磷(P31)水平下促进根系对磷的吸收。在缺硒(Se0)条件下,施磷(P3.1和P31)处理显著提高冬小麦地上部和根系硒含量、累积量以及硒的迁移系数;在低硒(Se0.1)和高硒(Se1)条件下,施磷(P3.1和P31)显著降低小麦幼苗硒含量、累积量和迁移系数,存在显著的拮抗作用。【结论】对于冬小麦幼苗磷、硒的吸收和转运,磷、硒之间存在既相互促进又相互拮抗的效应,这种效应与磷、硒的施用水平有一定关系。 展开更多
关键词 吸收 转运 冬小麦 水培
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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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施氮量对不同品种小麦物质积累、转运及产量的影响
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作者 姜丽娜 张雅雯 +1 位作者 朱娅林 赵凌霄 《作物杂志》 CAS 北大核心 2019年第5期151-158,共8页
在大田条件下,以豫麦49-198、郑麦0943、百农418、许科316为试验材料,设置施纯氮120kg/hm^2(N1)、210kg/hm^2(N2)、300kg/hm^2(N3)3个施氮水平,比较分析不同施氮量对不同品种小麦干物质、氮素积累与转运以及产量的影响。结果表明:同一... 在大田条件下,以豫麦49-198、郑麦0943、百农418、许科316为试验材料,设置施纯氮120kg/hm^2(N1)、210kg/hm^2(N2)、300kg/hm^2(N3)3个施氮水平,比较分析不同施氮量对不同品种小麦干物质、氮素积累与转运以及产量的影响。结果表明:同一品种不同施氮量处理、同一施氮量不同品种间小麦干物质积累量、干物质转运规律和氮素积累量、氮素转运规律以及子粒产量存在显著差异。适当增施氮肥可以有效增加小麦植株群体干物质积累量,成熟期,豫麦49-198和郑麦0943在N2处理干物质积累量最高,百农418和许科316在N3处理干物质积累量最高。不同品种小麦营养器官花前贮藏干物质和氮素的转运量、转运率以及物质转运对子粒的贡献率均在N2处理达到最高。豫麦49-198和郑麦0943在N2处理获得最高产量,分别达8 036.67和6 873.33kg/hm^2,百农418和许科316在N3处理获得最高产量,分别为7 636.67和7 713.33kg/hm^2。因此,在小麦生产过程中,应根据不同品种合理施氮,实现高产。 展开更多
关键词 氮肥 品种 小麦 干物质 积累 转运 产量
Translocation of Otostegia bucharica, a highly threatened narrowly distributed relict shrub
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作者 Komiljon Tojibaev Natalia Beshko Sergei Volis 《植物多样性:英文版》 CAS CSCD 2019年第2期105-108,共4页
Translocation is a recognized means of rescuing imperiled species but the evidence for the long-term success of translocations is limited. We report the successful translocation of reproductive individuals of a critic... Translocation is a recognized means of rescuing imperiled species but the evidence for the long-term success of translocations is limited. We report the successful translocation of reproductive individuals of a critically endangered shrub Otostegia bucharica from a site facing imminent habitat destruction into a nearby natural population of the species. The relocated plants were visited the year after planting and 13 years later to assess short-and long-term plant survival. Significant percentage of plants that survived transplanting shock and very dry spring following transplanting(around 36%), and further decrease of this number in the next 12 years by only 14%, indicated that O. bucharica is amenable to translocation using reproductive plants. Based on results of species distribution modeling, and failed attempts of ex situ cultivation, we propose introduction of this species into areas with suitable climatic and soil conditions.However, because there is currently no nature reserve in Uzbekistan having suitable conditions for the species under the present climate and that expected in the near future, and because all known habitats of O. bucharica are exposed to the very strong anthropogenic pressure, establishment of a new protected area, awareness building and involvement of local community in conservation activities are required to prevent extinction of this extremely rare species. 展开更多
关键词 ENDANGERED PLANT species SDM TRANSLOCATION Ins itu PLANT conservation
一例染色体复杂易位致胎儿多发畸形的遗传学诊断 预览
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作者 罗玉琴 沈敏 +6 位作者 孙义锡 钱叶青 王丽雅 俞佳玲 胡珺洁 金帆 董旻岳 《浙江大学学报:医学版》 CAS CSCD 北大核心 2019年第4期397-402,共6页
目的:对一例染色体复杂易位致多发畸形胎儿进行遗传学分析和诊断。方法:对一例多发畸形胎儿行G显带染色体核型分析、单核苷酸多态性微阵列(SNParray)及荧光原位杂交(FISH)检测。胎儿父母行外周血染色体核型分析及FISH检测。结果:胎儿的... 目的:对一例染色体复杂易位致多发畸形胎儿进行遗传学分析和诊断。方法:对一例多发畸形胎儿行G显带染色体核型分析、单核苷酸多态性微阵列(SNParray)及荧光原位杂交(FISH)检测。胎儿父母行外周血染色体核型分析及FISH检测。结果:胎儿的羊水染色体核型为46,XN,t(12;13)(q22;q32)。SNParray显示胎儿存在1q42.13q44重复(20192kb)及15q26.1q26.3缺失(13293kb),核型分析与基因芯片结果不一致。FISH验证了SNParray的结果。母亲外周血FISH结果确认为隐匿性46,XX,t(1;15)(q42.1;q26.1)携带者,而胎儿遗传了其中一条衍生的15号染色体der(15)t(1;15)(q42.1;q26.1)。即胎儿遗传了父亲的t(12;13)(q22;q32)平衡易位及母亲的隐匿性平衡易位形成的衍生15号染色体。结论:1q42.13q44重复和15q26.1q26.3缺失是导致本例胎儿畸形的遗传学病因,产前诊断时多种遗传学技术联合应用可为临床提供准确的诊断。 展开更多
关键词 胎儿/畸形 染色体 易位 遗传 多态性 单核苷酸 微阵列分析 异常核型 产前诊断 原位杂交 荧光
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不同氮效率玉米品种亲本自交系花粒期氮素转运特性 预览
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作者 温立玉 薛艳芳 +4 位作者 张慧 张秀清 高英波 刘开昌 李宗新 《植物营养与肥料学报》 CAS CSCD 北大核心 2019年第4期568-578,共11页
【目的】为明确不同氮效率玉米品种亲本自交系花粒期氮转运与代谢特性,从溯源的角度探析不同氮效率玉米品种亲本自交系花粒期的氮素吸收、转运与利用特性。【方法】以氮高效型玉米品种‘鲁单818’的亲本自交系(母本Qx508,父本Qxh0121)... 【目的】为明确不同氮效率玉米品种亲本自交系花粒期氮转运与代谢特性,从溯源的角度探析不同氮效率玉米品种亲本自交系花粒期的氮素吸收、转运与利用特性。【方法】以氮高效型玉米品种‘鲁单818’的亲本自交系(母本Qx508,父本Qxh0121)和氮低效型玉米品种‘鲁单981’亲本自交系(母本Q319,父本Lx9801)为供试材料,盆栽条件下研究不同氮素供应水平(N 0 g/盆、7.1 g/盆和14.2 g/盆,记作N0、N1和N2)对4个不同氮效率玉米亲本自交系花粒期干物质积累、氮素积累、氮素分配与利用效率以及叶片氮代谢关键酶硝酸还原酶活性、可溶性蛋白含量变化的影响,并探讨分析不同氮效率玉米品种氮素利用的生理机制与遗传特性。【结果】吐丝后各自交系干物质由营养器官向生殖器官转移,表现为茎叶干物重显著降低,穗和粒的干物重显著增加,且Qxh0121和Q319的干物质重均显著高于其另一亲本。从吐丝到成熟,茎鞘和叶的氮含量均呈降低的趋势,穗和粒的氮含量显著增加,且Qxh0121和Q319自交系叶片、茎鞘、籽粒氮含量均显著高于其另一亲本自交系。花后氮吸收量均表现为Qxh0121显著高于Qx508,Q319显著高于Lx9801。且在低氮(N1)和高氮(N2)处理下,Qxh0121氮转运效率较Qx508分别高29.2%和14.3%,花后氮转运对籽粒贡献率较Qx508分别高74.0%和17.4%。Q319氮转运效率较Lx9801分别高43.4%和24.7%,花后氮转运对籽粒贡献率较Lx9801分别高75.3%和39.6%。Qxh0121和Q319的产量和氮肥利用效率也高于对应的自交系。在N1和N2水平下,Qxh0121的产量比Qx508分别高43.3%和42.5%,Q319的产量比Lx9801分别高20.2%和10.5%。吐丝至成熟期叶片硝酸还原酶(NR)活性和可溶性蛋白含量的变化均呈单峰曲线,高峰期在吐丝后10 d左右。Qxh0121和Q319的NR活性和可溶性蛋白含量在各时期均高于其另一亲本,表现出较强的氮素吸收和同化能力。【结论】氮高� 展开更多
关键词 玉米 自交系 花粒期 转运
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Intestinal permeability in the pathogenesis of liver damage:From non-alcoholic fatty liver disease to liver transplantation 预览
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作者 Alberto Nicoletti Francesca Romana Ponziani +6 位作者 Marco Biolato Venanzio Valenza Giuseppe Marrone Gabriele Sganga Antonio Gasbarrini Luca Miele Antonio Grieco 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第33期4814-4834,共21页
The intimate connection and the strict mutual cooperation between the gut and the liver realizes a functional entity called gut-liver axis.The integrity of intestinal barrier is crucial for the maintenance of liver ho... The intimate connection and the strict mutual cooperation between the gut and the liver realizes a functional entity called gut-liver axis.The integrity of intestinal barrier is crucial for the maintenance of liver homeostasis.In this mutual relationship,the liver acts as a second firewall towards potentially harmful substances translocated from the gut,and is,in turn,is implicated in the regulation of the barrier.Increasing evidence has highlighted the relevance of increased intestinal permeability and consequent bacterial translocation in the development of liver damage.In particular,in patients with non-alcoholic fatty liver disease recent hypotheses are considering intestinal permeability impairment,diet and gut dysbiosis as the primary pathogenic trigger.In advanced liver disease,intestinal permeability is enhanced by portal hypertension.The clinical consequence is an increased bacterial translocation that further worsens liver damage.Furthermore,this pathogenic mechanism is implicated in most of liver cirrhosis complications,such as spontaneous bacterial peritonitis,hepatorenal syndrome,portal vein thrombosis,hepatic encephalopathy,and hepatocellular carcinoma.After liver transplantation,the decrease in portal pressure should determine beneficial effects on the gut-liver axis,although are incompletely understood data on the modifications of the intestinal permeability and gut microbiota composition are still lacking.How the modulation of the intestinal permeability could prevent the initiation and progression of liver disease is still an uncovered area,which deserves further attention. 展开更多
关键词 Bacterial TRANSLOCATION GUT MICROBIOTA Gut-liver axis LIVER disease CIRRHOSIS Mediterranean diet PERSONALIZED medicine
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Seed filling dynamic traits of oil flax in response to nitrogen and phosphorus 预览
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作者 Yaping Xie Bin Wang +8 位作者 Limin Wang Junyi Niu Wei Zhao Bin Yan Li Zhao Zhao Dang Wenjuan Li Yanni Qi Jianping Zhang 《Oil Crop Science-中国油料作物学报英文版》 2019年第3期152-165,共14页
Crop yield is primarily seed-filling-limited in production system under field conditions.This study was aimed to determine whether seed filling traits of oil flax(Linum usitatissimum L.)could be controlled by phosphor... Crop yield is primarily seed-filling-limited in production system under field conditions.This study was aimed to determine whether seed filling traits of oil flax(Linum usitatissimum L.)could be controlled by phosphorus(P),nitrogen(N),and phosphorus and nitrogen(NP)supply.Effects on seed filling traits were investigated in 2 years including capsule diameter,capsule height,capsule dry matter(DM),seed DM per capsule,pericarp DM per capsule,protein content and oil content.DM translocation from pericarps to seed,translocation efficiency,and contribution of photoassimilates during seed filling period were also detected.In a randomized complete block design,cultivar'Longyaza 1'was grown under P(33 kg P/ha),N(75 kg N/ha),and NP(33 kg P/ha and 75 kg N/ha)along with a zerofertilizer(CK)treatment in 2013 and 2014.Results suggested that DM translocation efficiency and contribution efficiency increased to different extent due to P,N or NP application.At 42 DAA(days after anthesis),seed DM per capsule reached the greatest,while protein content and pericarp DM obtained the least level.However,the highest oil content was detected at 35 DAA.A significant positive linear relationship was observed between seed DM,capsule DM and DM translocation in both years.Protein content showed inconsistent relation with oil content.The results indicated that appropriate N and P management could be an effective approach to increase oil flax production. 展开更多
关键词 oil flax NITROGEN PHOSPHORUS seed filling dry matter translocation efficiency contribution efficiency protein content oil content
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Vertical Distribution of Soil Pyrogenic Matter: A Review
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作者 Eleanor HOBLEY 《土壤圈:英文版》 SCIE CAS CSCD 2019年第2期137-149,共13页
Alteration of terrestrial biomass during fire produces pyrogenic matter, a large quantity of which is deposited on and may enter soils. The amount of annual burning around the globe implies greater production and stor... Alteration of terrestrial biomass during fire produces pyrogenic matter, a large quantity of which is deposited on and may enter soils. The amount of annual burning around the globe implies greater production and storage of carbon in soil pyrogenic organic matter(pyrOM) than is regularly found in investigations of soil pyrogenic matter. A portion of this unaccounted for pyrogenic material may be translocated to subsurface soil depths, which is frequently excluded from soil investigations, and the presence of subsoil charcoal helps to partially fill this pyrOM gap. In this paper, I discuss the mechanisms for vertical redistribution of pyrogenic matter in soils and develop conceptual models to describe the depth, particle size, and age distribution of pyrogenic matter resulting from different translocation mechanisms. Based on the relationships between pyrogenic matter turnover and translocation, the suitability of pyrogenic matter in soils as an indicator for soil processes is discussed. Deciphering the relationships between pyrogenic matter depth, particle size, and age distribution yields valuable insights into the dynamics of soil forming processes as well as soil pyrogenic matter turnover,which should therefore, be a focus of future studies. 展开更多
关键词 age black carbon charcoal MOBILITY organic MATTER PARTICLE size SUBSOIL TRANSLOCATION
不同玉米品种对土壤镉富集和转运的差异研究 预览
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作者 邓婷 卢维盛 +4 位作者 吴家龙 赵宇 赵杨 姚元梦 李贵杰 《华南农业大学学报》 CAS CSCD 北大核心 2019年第4期33-39,共7页
[目的]通过盆栽试验研究11个玉米Zea mays品种的Cd富集和转运能力,并进行筛选,旨在为探究和发掘Cd高累积玉米品种提供一定的理论参考。[方法]以11个玉米品种为研究对象,在全Cd质量分数为2.5 mg kg 1的土壤中培养50 d,测定玉米干质量、C... [目的]通过盆栽试验研究11个玉米Zea mays品种的Cd富集和转运能力,并进行筛选,旨在为探究和发掘Cd高累积玉米品种提供一定的理论参考。[方法]以11个玉米品种为研究对象,在全Cd质量分数为2.5 mg kg 1的土壤中培养50 d,测定玉米干质量、Cd含量,采用方差分析和主成分分析法研究不同品种玉米在Cd污染土壤中的干质量、Cd富集和转运能力的差异。[结果]11个品种玉米的根、茎叶的干质量、Cd质量分数、富集系数和转运系数间均差异显著(P<0.05)。华彩糯3号和广红糯8号玉米茎叶Cd质量分数分别为26.66和20.25 mg kg 1、富集系数分别为10.66和8.10、转运系数分别为1.46和2.16,均显著高于其他品种(P<0.05);主成分分析结果显示,华彩糯3号和广红糯8号玉米对Cd的富集和转运能力强于其他品种(P<0.01)。[结论]华彩糯3号和广红糯8号玉米对Cd的富集和转运能力较强,属于Cd高累积玉米品种,在Cd污染土壤修复中具有较大的应用潜力。 展开更多
关键词 玉米 土壤 镉富集 转运 品种筛选
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施氮量对‘商麦156’干物质积累、转运及产量的影响 预览
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作者 朱倩 倪雪峰 +3 位作者 闫向泉 孟自力 朱伟 王和洲 《中国农学通报》 2019年第13期12-15,共4页
在大田试验条件下以小麦新品种’商麦156’为材料,通过设置N1 (0 kg/hm~2)、N2 (120 kg/hm~2)、N3 (225 kg/hm~2)、N4 (330 kg/hm~2) 4个施氮水平,研究不同施氮量对’商麦156’干物质积累、分配、转运及产量的影响。结果表明:在一定范围... 在大田试验条件下以小麦新品种’商麦156’为材料,通过设置N1 (0 kg/hm~2)、N2 (120 kg/hm~2)、N3 (225 kg/hm~2)、N4 (330 kg/hm~2) 4个施氮水平,研究不同施氮量对’商麦156’干物质积累、分配、转运及产量的影响。结果表明:在一定范围(0~225 kg/hm~2)内施加氮肥有利于’商麦156’干物质的积累,同时可以促进生长发育前期营养器官中积累的光合产物向穗转运和分配。’商麦156’干物质转运量、转运率和对籽粒的贡献率均以N3 (225 kg/hm~2)处理最高;单位面积穗数随施氮量的增加而增加,穗粒数和千粒重随施氮量的增加表现为先增后减的趋势,最终产量表现为N3>N2>N4>N1,其中N3与N2差异不显著,与N4、N1差异极显著。综上所述,本试验条件下’商麦156’的最适施氮量为225 kg/hm~2。 展开更多
关键词 '商麦156’ 施氮量 干物质积累 分配 转运 产量
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Molecular Mechanism of the Specificity of Protein Import into Chloroplasts and Mitochondria in Plant Cells
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作者 Dong Wook Lee Sumin Lee +4 位作者 Junho Lee Seungjin Woo Md.Abdur Razzak Alessandro Vitale Inhwan Hwang 《分子植物:英文版》 SCIE CAS CSCD 2019年第7期951-966,共16页
Plants possess both types of endosymbiotic organelles, chloroplasts and mitochondria. Transit peptides and presequences function as signal sequences for specific import into chloroplasts and mitochondria, respectively... Plants possess both types of endosymbiotic organelles, chloroplasts and mitochondria. Transit peptides and presequences function as signal sequences for specific import into chloroplasts and mitochondria, respectively. However, how these highly similar signal sequences confer the protein import specificity remains elusive. Here, we show that mitochondrial- or chloroplast-specific import involves two distinct steps, specificity determination and translocation across envelopes, which are mediated by the N-terminal regions and functionally interchangeable C-terminal regions, respectively, of transit peptides and presequences. A domain harboring multiple-arginine and hydrophobic sequence motifs in the N-terminal regions of presequences was identified as the mitochondrial specificity factor. The presence of this domain and the absence of arginine residues in the N-terminal regions of otherwise common targeting signals confers specificity of protein import into mitochondria and chloroplasts, respectively. AtToc159, a chloroplast import receptor, also contributes to determining chloroplast import specificity. We propose that common ancestral sequences were functionalized into mitochondrial- and chloroplast-specific signal sequences by the presence and absence, respectively, of multiple-arginine and hydrophobic sequence motifs in the N-terminal region. 展开更多
关键词 transit peptide presequence protein IMPORT into CHLOROPLASTS and MITOCHONDRIA N-terminal SPECIFICITY DOMAIN C-TERMINAL common translocation DOMAIN IMPORT SPECIFICITY determination
Effect of broad-spectrum antibiotics on bacterial translocation in burned or septic rats
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作者 Zhen-Liang Wen Li-Di Zhang +3 位作者 Shao-Ze Liu Jiao Liu Yi-Zhu Chen De-Chang Chen 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第10期1179-1187,共9页
Background: Antibiotics are frequently used to treat critically ill patients, and its use is often accompanied by intestinal dysbiosis might further lead to bacterial translocation (BT). Nevertheless, studies on the r... Background: Antibiotics are frequently used to treat critically ill patients, and its use is often accompanied by intestinal dysbiosis might further lead to bacterial translocation (BT). Nevertheless, studies on the relationship between antibiotic therapy and BT are rare. In the present study, we investigated the effect of broad-spectrum antibiotics on BT in an experimental rat model of burn or sepsis injury. Methods: The septic rat model was simulated by a second insult with lipopolysaccharides after burn injury. Ninety-two male Sprague-Dawley rats were randomly divided into control, burn, and sepsis groups (n = 8 or 9, each group), and the latter two groups were then treated with imipenem or ceftriaxone for 3 or 9 days. The mesenteric lymph nodes, liver, lungs, and blood were collected at each time point under sterile conditions for quantitative bacterial culture and strain identification. The differences between the groups were compared by Fisher exact test or Mann-Whitney U test. Results: Only minimal Escherichia coli translocation to the mesenteric lymph nodes was observed in the normal control group, in which the BT rate was 12.5%. Burn injury did not affect the BT rate (Burn group vs. Control group, 12.5% vs. 12.5%, P = 1.000), whereas the BT rate showed an increased trend after the second insult with lipopolysaccharide (Sepsis group us. Control group, 44.4% 12.5%, P = 0.294), and many strains of Enterobacteria spp. were detected in distant organs (liver, lung, and blood)[Sepsis group vs. Control group, 0 (0,3) us. 0 (0,0), U = 20, P = 0.045]. After the antibiotic treatment, BT to the distant organs was increased in burned rats [Burn IT3 group us. Burn group, 0 (0,2) vs. 0 (0,0);Burn IT9 group vs. Burn group, 0 (0,1) vs. 0 (0,0);Burn CT9 group Burn group, 0 (0,2) vs. 0 (0,0);all U = 20 and P = 0.076] but decreased in septic rats [Sepsis CT3 group vs. Sepsis group, 0 (0,0) vs. 0 (0,3), U = 20, P = 0.045]. The total amount of translocated bacteria, regardless of which antibiotic was used, was increased in bu 展开更多
关键词 Antibiotic BACTERIAL TRANSLOCATION ENTEROCOCCI ENTEROBACTERIA SEPSIS
玉米对镉的转运、积累机制及其生理响应 预览
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作者 沈天尔 施洁 +4 位作者 胡盈盈 顾家家 郭燕萍 廖芳蕾 陈文荣 《中国粮油学报》 EI CAS CSCD 北大核心 2019年第9期139-146,共8页
土壤镉(Cd)污染是我国乃至全球性的环境问题,玉米(Zea mays L.)对Cd具有较强的吸收及积累能力。探明玉米吸收累积Cd的生理分子机制是阻控土壤中镉进入玉米可食部进而威胁人体健康的关键所在。在根部Cd的短距离运输过程中,植物螯合素分... 土壤镉(Cd)污染是我国乃至全球性的环境问题,玉米(Zea mays L.)对Cd具有较强的吸收及积累能力。探明玉米吸收累积Cd的生理分子机制是阻控土壤中镉进入玉米可食部进而威胁人体健康的关键所在。在根部Cd的短距离运输过程中,植物螯合素分泌、各类离子通道和转运蛋白参与的液泡区隔化是Cd吸收、运输与积累的关键因素;而在长距离运输中,韧皮部的装载和卸载在Cd向玉米籽粒的转运积累中发挥主要作用。其次,Cd在玉米植株体内的转运积累过程也诱发了其对镉胁迫的生理响应,主要表现在激素水平、光合作用、水分吸收和矿质元素吸收等方面的变化上。本文主要综述了该生理机制的研究进展,并提出了降低玉米Cd积累的农艺防控措施。 展开更多
关键词 玉米 生理响应 镉积累 转运
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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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不同土壤耕作模式对双季稻区水稻植株养分积累与转运的影响 预览
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作者 唐海明 肖小平 +6 位作者 李超 汤文光 郭立君 程凯凯 汪柯 潘孝晨 李微艳 《南京农业大学学报》 CAS CSCD 北大核心 2019年第2期220-228,共9页
[目的]本文旨在明确双季稻区不同土壤耕作模式对水稻植株干物质和养分积累与分配的影响。[方法]采用紫云英-双季稻种植模式结合不同土壤耕作模式大田定位试验,以双季水稻旋耕+秸秆不还田为对照(RTO),应用常规分析方法开展了双季水稻翻耕... [目的]本文旨在明确双季稻区不同土壤耕作模式对水稻植株干物质和养分积累与分配的影响。[方法]采用紫云英-双季稻种植模式结合不同土壤耕作模式大田定位试验,以双季水稻旋耕+秸秆不还田为对照(RTO),应用常规分析方法开展了双季水稻翻耕+秸秆还田(CT)、双季水稻旋耕+秸秆还田(RT)、双季水稻免耕+秸秆还田(NT)处理对双季水稻植株各器官干物质和氮、磷、钾积累与分配影响的研究。[结果]早稻和晚稻成熟期,RT和CT处理均有利于增加水稻植株茎、叶、穗和地上部干物质积累量及茎叶干物质转运量;CT、RT和NT处理植株茎叶物质转运率和物质贡献率均高于RTO处理;NT处理抽穗后物质同化贡献率均为最高,均高于CT、RT和RTO处理。早稻和晚稻成熟期,RT处理水稻植株茎的氮素积累量均显著高于CT、NT和RTO处理,CT、RT和NT处理植株穗和地上部的氮素积累量均显著高于RTO处理。CT和RT处理植株茎和叶的磷素积累量均显著高于NT和RTO处理;CT、RT和NT处理植株穗和地上部的磷素积累量均显著高于RTO处理。CT和RT处理植株茎和地上部的钾素积累量均显著高于RTO处理;CT处理植株叶和穗的钾素积累量均显著高于RTO处理。[结论]秸秆还田措施促进了水稻植株各器官干物质积累和转运;其中以土壤翻耕、旋耕结合秸秆还田措施有利于水稻植株群体养分的积累与转运。 展开更多
关键词 水稻 土壤耕作 干物质 积累 转运
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不同花生品种对稻田镉富集及转运的研究 预览
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作者 王飞 王建国 +5 位作者 刘登望 李林 万书波 张昊 张利青 邹冬生 《中国油料作物学报》 CAS CSCD 北大核心 2019年第4期568-576,共9页
为研究湖南湘江流域稻田镉(Cd)污染治理方法,筛选稻田替代种植作物,于长沙县和湘阴市受污染稻田改种花生,选用5个大果品种,设置2种(露地、覆膜)栽培方式,研究品种与栽培方式组合下对稻田Cd吸收、富集及转运的影响。结果表明:稻田花生营... 为研究湖南湘江流域稻田镉(Cd)污染治理方法,筛选稻田替代种植作物,于长沙县和湘阴市受污染稻田改种花生,选用5个大果品种,设置2种(露地、覆膜)栽培方式,研究品种与栽培方式组合下对稻田Cd吸收、富集及转运的影响。结果表明:稻田花生营养器官(根、茎、叶)Cd含量较高,生殖器官(果壳、籽仁)Cd含量较低,且品种间有明显差异。5个花生品种的组织器官中Cd含量最高的是茎(5.413~8.859mg kg^-1),果壳和籽仁最少(0.523~1.326mg kg^-1),但是籽仁Cd含量超出NY/T1067-2006标准的规定值,食用安全存在风险。覆膜栽培尽管降低了花生茎、叶、果针、果壳及籽仁等的Cd含量,但提高了植株干物质重和Cd总积累,其中,营养器官(根、茎、叶)Cd富集系数高于2.5,生殖器官(果壳、籽仁)Cd富集系数为0.8~1.7。不同部位间Cd转移系数大小顺序为:根→茎秆>茎秆→叶>果壳→籽仁>果针→果壳>茎秆→果针。不同品种的花生油中Cd含量范围在0.012~0.074mg kg^-1,符合标准,因此花生油食用是安全的。以地上部单株干物质积累量及其Cd含量作为高镉积累筛选指标,5个品种中09-3106的单株可高积累镉元素。建议在湘阴、长沙等地的Cd污染稻田进行覆膜栽培花生。 展开更多
关键词 花生 品种 稻田 覆膜 富集 转运 食用安全
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A constitutional jumping translocation involving the Y and acrocentric chromosomes
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作者 Makiko Tsutsumi Naoko Fujita +8 位作者 Fumihiko Suzuki Takashi Mishima Satoko Fujieda Michiko Watari Nobuhiro Takahashi Hidefumi Tonoki Osamu Moriwaka Toshiaki Endo Hiroki Kuraliashi 《亚洲男性学杂志:英文版》 SCIE CAS CSCD 2019年第1期101-103,共3页
Dear Editor, Translocations of the same chromosomal fragments to two or more different chromosomes in different somatic cell lineages are referred to as jumping translocations (JTs).JTs have been mainly reported in he... Dear Editor, Translocations of the same chromosomal fragments to two or more different chromosomes in different somatic cell lineages are referred to as jumping translocations (JTs).JTs have been mainly reported in hematological malignancies but have been observed in rare instances also as constitutional chromosomal aberrations.2 The underlying JT mechanism remains unclear,however. 展开更多
关键词 acrocentric chromosomes JUMPING TRANSLOCATION
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