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谷氨酸肥对阿拉尔地区主干型苹果树体生长的影响
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作者 魏智博 周高兴 +1 位作者 谢晓东 王新建 《绿色科技》 2023年第1期108-112,共5页
为给阿克苏地区的苹果栽培提供技术支撑,以两年生烟富8号为试体,探讨了增施土壤和叶面混合配比的复合谷氨酸液颗粒肥,研究了不同配比浓度对于试验试体生长的影响,为该地区果树高效优质生产提供理论依据。结果表明:每亩施用200 kg复合谷... 为给阿克苏地区的苹果栽培提供技术支撑,以两年生烟富8号为试体,探讨了增施土壤和叶面混合配比的复合谷氨酸液颗粒肥,研究了不同配比浓度对于试验试体生长的影响,为该地区果树高效优质生产提供理论依据。结果表明:每亩施用200 kg复合谷氨酸液颗粒肥同时喷施200倍复合谷氨酸液肥,能显著增加株高、茎粗、新梢以及叶片的增长量。在土壤施肥结合叶面喷施的9种不同处理下树体的株高、茎粗、新梢以及叶片都呈增长趋势,其中在土壤施肥量相同的条件下,200倍叶面喷施肥比400倍和600倍对于株高和新梢的促进作用更好。 展开更多
关键词 谷氨酸肥 阿克苏 苹果生长
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直立中央领导干树形条件下幼年苹果树体生长特性的研究 被引量:37
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作者 李绍华 李明 +1 位作者 刘国杰 孟昭清 《中国农业科学》 CAS CSCD 北大核心 2002年第7期826-830,共5页
在直立中央领导干树形条件下 ,M7、MM10 6、M 2 6中间砧幼年苹果树中心干生长速度快 ,4年生树高达到 2 .7~ 3.6m。中心干上抽生的侧枝数量多 ,红富士、王林、新红星和乔纳金 4个品种在 4年生时分别在 2 0~ 30 .5个之间 ,且主要在 2年... 在直立中央领导干树形条件下 ,M7、MM10 6、M 2 6中间砧幼年苹果树中心干生长速度快 ,4年生树高达到 2 .7~ 3.6m。中心干上抽生的侧枝数量多 ,红富士、王林、新红星和乔纳金 4个品种在 4年生时分别在 2 0~ 30 .5个之间 ,且主要在 2年生或者 2年生和 1年生中心干段上抽生侧生分枝。 4年生树相指标能满足生产上早果丰产的需要 :单株枝量大 ,乔纳金为 6 31个 ,红富士和王林 4 80个左右 ,新红星 312个 ;短枝比率高 ,红富士短枝占总枝量的 6 1% ,乔纳金和王林分别为 71%和 74 % ,新红星 81% ;侧生分枝角度开张 ,在 4 3°~ 6 9°之间 ;中心干及侧生分枝的生长势能够很快趋向缓和 ,在不采用任何人工控制生长措施的条件下 ,定植后的第 4年 ,主干的延迟生长量显著大幅度减弱 ,侧生分枝生长量在抽生的第 3年甚至是第 2年也显著地减小。 展开更多
关键词 生长特性 幼年苹果 营养生长 直立中央领导干树形
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苹果离体叶片培养直接体细胞胚胎发生研究 被引量:27
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作者 达克东 张松 +1 位作者 李雅志 亓增军 《园艺学报》 CAS CSCD 北大核心 1996年第3期241-245,共5页
在MS+BA10mg/L+NAA50mg/L+2,4_D0\^5mg/L+蔗糖20g/L的固体培养基上,苹果品种嗄拉试管苗叶片经7天暗培养产生胚性细胞。将具有胚性细胞的叶片转入MS+BA10mg/L+蔗糖20g... 在MS+BA10mg/L+NAA50mg/L+2,4_D0\^5mg/L+蔗糖20g/L的固体培养基上,苹果品种嗄拉试管苗叶片经7天暗培养产生胚性细胞。将具有胚性细胞的叶片转入MS+BA10mg/L+蔗糖20g/L的培养基上暗培养40天,65%的叶片直接发生体细胞胚,体细胞胚在同种培养基上萌发,长成小植株。 展开更多
关键词 苹果:离叶片培养 细胞胚 小植株
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3株苹果蠹蛾颗粒体病毒本土株的毒力测定与田间防效 被引量:9
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作者 甘恩宇 李晓峰 +4 位作者 于欢 吴正伟 徐利 张雅林 王敦 《西北农林科技大学学报(自然科学版)》 CSCD 北大核心 2011年第10期119-122,133,共5页
【目的】通过与比利时商用病毒株系CypoGV-BG的对比,研究3株国内苹果蠹蛾(Cydia pomonella)颗粒体病毒株系CypoGV-ZY、CypoGV-KS1、CypoGV-KS2的毒力和田间防治效果,为我国苹果蠹蛾的生物防治和病毒杀虫剂的研制奠定基础。【方法】采用... 【目的】通过与比利时商用病毒株系CypoGV-BG的对比,研究3株国内苹果蠹蛾(Cydia pomonella)颗粒体病毒株系CypoGV-ZY、CypoGV-KS1、CypoGV-KS2的毒力和田间防治效果,为我国苹果蠹蛾的生物防治和病毒杀虫剂的研制奠定基础。【方法】采用饲喂法研究3株病毒对苹果蠹蛾3龄幼虫的毒力大小。以性诱剂诱集的雄虫数量和受害果率为评价指标,检测3株苹果蠹蛾颗粒体病毒的田间防效。【结果】3株国内株系CypoGV-ZY、Cy-poGV-KS1和CypoGV-KS2对苹果蠹蛾3龄幼虫的LD50分别为3.43×104,8.81×104和1.04×105 OBs/mL,优于CypoGV-BG的5.31×105 OBs/mL;而病毒浓度为5×105 OBs/mL时,3株病毒株系的LT50分别为4.05,4.11和4.19d,与CypoGV-BG的4.98d差异不显著。田间防效结果表明,防治3个月后,从性诱剂诱集的雄虫数量看,3株本土病毒株防效均显著优于CypoGV-BG;从果实受害率看,CypoGV-ZY、CypoGV-KS1的果实受害率分别为39.5%和41.3%,与化学杀虫剂灭幼脲的防效(36.9%)接近,显著强于CypoGV-KS2和CypoGV-BG。【结论】CypoGV-ZY和CypoGV-KS1分离株对我国西北疫区的苹果蠹蛾具有较强的毒力及田间防治效果,防效明显优于国外商品病毒制剂。 展开更多
关键词 苹果蠹蛾颗粒病毒 毒力测定 田间防效
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苹果蠹蛾颗粒体病毒应用研究进展 被引量:1
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作者 黄晓萍 王洪秀 +3 位作者 戴陈伟 王金昌 关丽梅 靳亮 《江西科学》 2015年第3期303-307,336,共6页
苹果蠹蛾(Cydia pomonella(L.))属鳞翅目(Lepidoptera),卷叶蛾科(Tortricid),小卷蛾亚科(Olethreutinae),是一种重要的世界性蛀果害虫,严重威胁了我国新疆、甘肃和宁夏等地的苹果主产区的生产安全。苹果蠹蛾颗粒体病毒(Cydia pomonella ... 苹果蠹蛾(Cydia pomonella(L.))属鳞翅目(Lepidoptera),卷叶蛾科(Tortricid),小卷蛾亚科(Olethreutinae),是一种重要的世界性蛀果害虫,严重威胁了我国新疆、甘肃和宁夏等地的苹果主产区的生产安全。苹果蠹蛾颗粒体病毒(Cydia pomonella granulovirus,Cp GV)杀虫剂能够高效、专一的防治苹果蠹蛾种群的数量,在生物防治中起到了主要的控害作用,具有十分重要的经济和生态价值。从侵染过程、分子生物学研究(基因组特征)及防治、开发和应用前景等方面综述了苹果蠹蛾颗粒体病毒的研究进展。 展开更多
关键词 苹果蠹蛾颗粒病毒 致病性 生物杀虫剂
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人工饲料对苹果蠹蛾颗粒体病毒产量的影响 被引量:2
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作者 刘国锋 樊江斌 +2 位作者 吴正伟 梁召俊 王敦 《西北农业学报》 CAS CSCD 北大核心 2016年第7期1092-1096,共5页
优化增殖苹果蠹蛾颗粒体病毒张掖株(CypoGV-ZY)的饲料配方,为实现经济高效的病毒生产奠定技术基础。采用喂毒法,研究苹果蠹蛾人工饲料中苹果粉、酵母、小麦面粉、玉米粉4种主要营养成分不同配比对苹果蠹蛾幼虫生长及对CypoGV产量的影响... 优化增殖苹果蠹蛾颗粒体病毒张掖株(CypoGV-ZY)的饲料配方,为实现经济高效的病毒生产奠定技术基础。采用喂毒法,研究苹果蠹蛾人工饲料中苹果粉、酵母、小麦面粉、玉米粉4种主要营养成分不同配比对苹果蠹蛾幼虫生长及对CypoGV产量的影响。结果表明:添加酵母的饲料配方,幼虫体质量和病毒产量均显著提高;其中取食C配方饲料的染毒幼虫,病毒产量最高,单头死亡幼虫虫尸质量、单头幼虫产毒量及每克虫尸产毒量分别可达30.57mg、8.63×109和28.25×1010 g-1;用玉米粉取代该配方中的小麦面粉时,染毒幼虫的虫尸质量明显降低,病毒产量显著下降。可见,以酵母和小麦面粉作为主要营养成分的C配方饲料,能显著提高病毒的产量,最适于病毒增殖生产。 展开更多
关键词 苹果蠹蛾颗粒病毒 人工饲料 病毒产量
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稀土对山定子、红富士苹果树体与果实钙含量影响的研究 被引量:1
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作者 孙宝山 刘秀春 《北方果树》 2006年第2期7-8,共2页
水培试验表明,稀土有平衡树体钙素营养的作用,在钙浓度低时,稀土能促进果树对钙的吸收,在钙浓度高时,可在一定程度上抑制果树对钙的吸收。田间喷钙可促进果树对氮、钙、锌的吸收,并增加果实中钙的浓度。稀土、钙混合液浸果可使果实中钙... 水培试验表明,稀土有平衡树体钙素营养的作用,在钙浓度低时,稀土能促进果树对钙的吸收,在钙浓度高时,可在一定程度上抑制果树对钙的吸收。田间喷钙可促进果树对氮、钙、锌的吸收,并增加果实中钙的浓度。稀土、钙混合液浸果可使果实中钙浓度增加0.165%,保鲜率比对照增加26%。 展开更多
关键词 稀土 苹果 果实 钙含量
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微生物菌肥对苹果树体生长及病害防控的研究 被引量:3
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作者 武兴友 《农业与技术》 2017年第22期41-41,共1页
作为世界4大水果之一,苹果在世界范围内受到喜爱,被广泛种植,在我国也是十分重要的果树栽培品种,有着渊远的栽培历史。社会人口激增、科技水平进步等各种现实因素导致社会对水果的需求和要求越来越高。具体来说,普通消费者要求水果具备... 作为世界4大水果之一,苹果在世界范围内受到喜爱,被广泛种植,在我国也是十分重要的果树栽培品种,有着渊远的栽培历史。社会人口激增、科技水平进步等各种现实因素导致社会对水果的需求和要求越来越高。具体来说,普通消费者要求水果具备外观好、口感好并且便宜实惠的特点;就整个国家发展来说,要求水果的种植不能对其周围环境产生不利影响,不能破坏周围的生态环境。基于此,微生物菌肥作为一种现代化新型肥料,能有效地解决解决上述矛盾,保证生态型、环境友好型农业生产的基础上保证果树品质。国内目前关于微生物菌肥在果树,尤其是苹果树上的报道较少,对今后苹果树种植技术提升的指导意义较小。本文通过介绍目前我国苹果树生产中的常见疾病,结合微生物菌肥的特点,分析微生物菌肥对苹果树体生长及病害防控策略,旨在为今后生物菌肥的广泛使用以及苹果的高品质、高产量生产提供一定的理论基础。 展开更多
关键词 微生物菌肥 苹果 生长及病害防控
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红富士苹果树体抗寒性差的原因及预防
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作者 周吉生 冯凤菊 《河南科技》 2001年第11期18-19,共2页
关键词 红富士苹果 抗寒性 冻害 霜害 预防
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苜蓿银纹夜蛾核多角体病毒与Bt混合试剂对葡萄花翅小卷蛾的毒力分析
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作者 王洁 李玉英 +3 位作者 李子昂 阿地力·沙塔尔 李万倩 王琼 《中国生物防治学报》 CSCD 北大核心 2023年第2期313-319,共7页
为测定野生型和重组型苜蓿银纹夜蛾核型多角体病毒(Autographa californica multiple nucleopolyhedrovirus,Ac MNPV)在葡萄花翅小卷蛾生物防治中的应用潜力,本文以野生型和重组型Ac MNPV及其与苏云金杆菌(Bt)的混合试剂为试验材料,分... 为测定野生型和重组型苜蓿银纹夜蛾核型多角体病毒(Autographa californica multiple nucleopolyhedrovirus,Ac MNPV)在葡萄花翅小卷蛾生物防治中的应用潜力,本文以野生型和重组型Ac MNPV及其与苏云金杆菌(Bt)的混合试剂为试验材料,分别测定病毒及其与Bt的混合试剂对葡萄花翅小卷蛾幼虫的室内生物活性。研究结果表明:感染WT(野生型Ac MNPV)、WT-31(Ac MNPV携带苹果蠹蛾颗粒体病毒Cydia pomonella granulovirus(CpGV)orf31)、WTgp64-31(Ac MNPV缺失gp64基因、携带Cp GV orf31)的幼虫逐日死亡率呈现逐渐上升趋势,但作用速率缓慢;WT与WT-31的校正死亡率分别为80.36%、71.43%,并显著高于WTgp64-31(58.93%),但前两者之间差异不显著性。以WT和WT-31为基础,在混合有1000 IU/mL Bt的情况下,进一步分析表明,WT-31的LC50和LC90分别为1.66×10^(3)PIB/mL、3.07×10^(5)PIB/mL;浓度为104PIB/mL、105PIB/mL的WT-31的LT50分别为5.67 d、4.24 d,LT90分别为11.62 d、9.33 d;Ac MNPV能够感染葡萄花翅小卷蛾,较低浓度的Bt能够显著促进重组Ac MNPV(WT-31)的杀虫效率。研究结果将为葡萄花翅小卷蛾的生物防治提供理论依据。 展开更多
关键词 葡萄花翅小卷蛾 苜蓿银纹夜蛾核多角病毒 苹果蠹蛾颗粒病毒 苏云金杆菌
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叶面喷硒对苹果生长和果实品质的影响 被引量:2
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《中国果业信息》 2023年第5期54-54,共1页
据《中国果树》2023年第4期《叶面喷硒对烟富3号苹果树体生长、叶片光合特性与果实品质的影响》(作者杨喜盟等)报道,为探究喷硒对苹果的应用效果,以5年生烟富3号苹果为试材,研究了叶面喷不同浓度有机硒对树体生长、叶片光合特性和果实... 据《中国果树》2023年第4期《叶面喷硒对烟富3号苹果树体生长、叶片光合特性与果实品质的影响》(作者杨喜盟等)报道,为探究喷硒对苹果的应用效果,以5年生烟富3号苹果为试材,研究了叶面喷不同浓度有机硒对树体生长、叶片光合特性和果实硒含量、品质、产量的影响。 展开更多
关键词 果实品质 生长 有机硒 叶面喷硒 叶片光合特性 苹果生长 苹果 果实硒含量
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Genetic Structure of Malus sieversii Population from Xinjiang,China,Revealed by SSR Markers 被引量:32
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作者 张春雨 陈学森 +3 位作者 何天明 刘晓丽 冯涛 苑兆和 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第10期947-955,共9页
One hundred and nine Malus sieversii accessions from four geographical populations located at Kuerdening in Mohe town, Gongliu County, Jiaowutuohai, in Xinyuan County, Daxigou in Houcheng County of Ily State, and Baer... One hundred and nine Malus sieversii accessions from four geographical populations located at Kuerdening in Mohe town, Gongliu County, Jiaowutuohai, in Xinyuan County, Daxigou in Houcheng County of Ily State, and Baerluke Mountain in Yumin County of Tacheng State, Xinjiang Uygur Autonomous Region of China were studied by SSR markers. The purpose of the study was to determine the genetic structure and diversity in these eco-geographical populations with eight pair SSR primers of apple. The results indicated that: an average of 16 bands was detected in the four populations. The percentage of polymorphic bands in Gongliu population (89.06%) was the highest in the four populations. The average Nei's gene diversity index was 0.257 for all the loci. Totally, 128 polymorphic loci were detected and the percentage of polymorphic loci (P) was 100%, 88.28%, 84.83%, 87.50%, and 87.12%, respectively, at the species level and Gongliu, Xinyuan, Huocheng, and Yumin population levels. The Nei's gene diversity index (H = 0.2619) and Shannon's information index (1 = 0.4082) in the species level were higher than in the population level. The Nei's gene diversity index and Shannon's information index in the four populations were Gongliu 〉 Huocheng 〉 Xinyuan 〉 Yumin. Gongliu population and Xinyuan population were the highest in genetic identity and the closest in genetic distance. Gene flow between the populations was 7.265 based on genetic differentiation coefficient (GST = 0.064). The UPGMA cluster analysis indicated that the genetic relationships between the Gongliu and Xinyuan population were the closest, and the Yumin population were the farthest with the other three populations. The UPGMA cluster analysis indicated that the four geographical populations located in Gongliu, Xinyuan, Huocheng, and Yumin were relatively independent populations. Concurrently, there was also mild gene exchange between the populations. On the basis of the study of population genetic structure and the highest genetic diversity, Gongliu population should be given a high priority consideration in Malus sieversii population's in situ germplasm conservation. 展开更多
关键词 Malus sieversii SSR marker population genetic structure
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无试剂二氧化钛凝胶酶传感器检测苹果酸对映异构体研究 被引量:3
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作者 干宁 葛从辛 《中国食品学报》 EI CAS CSCD 2006年第6期105-111,共7页
研制了基于TiO2凝胶的D型和L型苹果酸脱氢酶(D-MDH、L-MDH)安培电化学传感器,并用它检测果汁饮料中D-苹果酸、L-苹果酸含量。利用气相沉积法在玻碳电极表面形成的TiO2凝胶膜,为固定化的MDH提供了一个生物兼容性的微环境。在溶解氧存在... 研制了基于TiO2凝胶的D型和L型苹果酸脱氢酶(D-MDH、L-MDH)安培电化学传感器,并用它检测果汁饮料中D-苹果酸、L-苹果酸含量。利用气相沉积法在玻碳电极表面形成的TiO2凝胶膜,为固定化的MDH提供了一个生物兼容性的微环境。在溶解氧存在的条件下,苹果酸被凝胶膜中的MDH催化氧化,其氧化产物在电位55mV下有电流响应,利用此响应值对苹果酸进行测定,测定时不需要向体系中添加媒介体。D-MDH/TiO2、L-MDH/TiO2两电极对苹果酸表现出快速的响应(响应时间小于10s)。传感器对苹果酸的测定具有较宽的线性范围(1×10-6~2×10-4mol/L)和较低的检测限(0.5×10-6mol/L)。由计算得到的固定化L-MDH和D-MDH的表观米氏常数(KMapp)分别为0.29mmol/L和0.31mmol/L。两电极具有较高的稳定性。本法快速、灵敏度高、选择性强,适合于测定果汁饮料中的苹果酸对映异构体。 展开更多
关键词 生物传感器 苹果酸脱氢酶 电化学检测TiO2凝胶 苹果酸对映异构 果汁
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Field Trials of CpGV Virus Isolates Overcoming Resistance to CpGV-M
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作者 M. Berling J. -B. Rey +5 位作者 S. -J. Ondet Y. Tallot O. Soubabère A. Bonhomme B. Sauphanor M. Lopez-Ferber 《Virologica Sinica》 SCIE CAS CSCD 2009年第5期470-477,共8页
The Cydia pomonella granulovirus (CpGV) has been used for many years as biological agent for codling moth control in apple orchards. Resistance to the Mexican strain of CpGV was detected in orchards in Germany, France... The Cydia pomonella granulovirus (CpGV) has been used for many years as biological agent for codling moth control in apple orchards. Resistance to the Mexican strain of CpGV was detected in orchards in Germany, France and Italy. A laboratory insect colony was started from insects collected in a French resistant orchard. It was named RGV. Various virus isolates were identified as active against this resistant insect colony. Field tests were carried out in 2007 to test if the two virus isolates CpGV-I12 and NPP-R1 were effective in the field. Although these virus isolates were not able to reduce insect caused fruit damages, they significantly reduced the overwintering insect populations. NPP-R1 was subjected to eight passages on RGV larvae (NPP-R1.8) that improved its biological activity on RGV larvae. 2008 field trials were set up to test this improved virus strain, compared to CpGV-I12 and Madex plus active on RGV. These tests confirmed the ability to control both in susceptible and resistant insect populations. 展开更多
关键词 Cydia pomonella Codling moth Biological control Genotype selection Field trials
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Chromosomal localization of ribosomal DNA sequences in an apple rootstock using a digoxygenin detection system
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作者 ZHU JIMEI S E GARDINER (The Horticulture and Food Research Institute of New Zealand Limited) (Mt Albert Research Centre, Privatc Bag 92 169, Auck-land, New Zealand)(Batchelar Research Centre, Private Bag 11 030,Palmerston North, New Zealand) 《Cell Research》 SCIE CAS CSCD 1995年第1期1-7,共7页
A 6kb rDNA probe comprising the 18S coding plusspacer sequences has been hybridized to the metaphase chromosomes of apple rootstock cultivar MM106 demon-strating the localization of ribosomal gene arrays in the vicini... A 6kb rDNA probe comprising the 18S coding plusspacer sequences has been hybridized to the metaphase chromosomes of apple rootstock cultivar MM106 demon-strating the localization of ribosomal gene arrays in the vicinity of the telomeric regions of the short arms of chro-mosomes 6 and 14. The in situ results using digoxygenin labelling coupled to an alkaline phosphatase immunoassay were confirmed by silver staining for NORs and nucleoli. This study demonstrates the feasibility of molecular cyto-genetic analysis of very small chromosomes (1.0-2.7μm)of apple. 展开更多
关键词 MALUS chromosomes in situ hybridization karyotype analysis silver staining
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Effects of Sunitinib Malate on Growth of Human Bladder Transitional Cell Line T24 In Vitro 被引量:1
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作者 Jin Wen Han-zhong Li +1 位作者 Zhi-gang Ji Jing Jin 《Chinese Medical Sciences Journal》 CAS CSCD 2015年第1期51-55,共5页
Objective To investigate the growth-inhibitory effect of sunitinib malate on human bladder transitional cell carcinoma (TCC) in vitro. Methods Human bladder TCC cell line T24 was cultured and exposed to graded conc... Objective To investigate the growth-inhibitory effect of sunitinib malate on human bladder transitional cell carcinoma (TCC) in vitro. Methods Human bladder TCC cell line T24 was cultured and exposed to graded concentrations of sunitinib malate for 72 hours in vitro to determine the sensitivities to drug. Cell viability was measured by MTT assay. Cell apoptotic morphology was observed by fluorescence microscope following DAPl staining. Band expressions of Fas, Fas ligand, poly (ADP-ribose) polyrnerase (PARP) and D-actin were analyzed by Western blot. Wound healing process of T24 cells exposed to sunitinib malate was assayed. Results Sunitinib malate exerted a concentration-dependent and time-dependent inhibitory effect on the T24 cell lines. Fluorescence microscopy showed that small vacuoles appeared in the nuclei of T24 cells and the vacuoles were bigger with higher drug concentrations. The expressions of Fas ligand and PARP in T24 cells treated with sunitinib malate exhibited a concentration-dependent increase. Moreover sunitinib malate suppressed the wound healing process in a concentration-dependent manner. Conclusion Sunitinib malate exerted marked inhibitory activity against bladder cancer cell line T24. 展开更多
关键词 SUNITINIB bladder cancer PROLIFERATION
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Effect of Crystallization Conditions on Polymorphic Diversity of Malic Acid RS-Racemate
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作者 Isakov A I Kotelnikova E N +1 位作者 Kryuchkova L Yu Lorenz H 《Transactions of Tianjin University》 EI CAS 2013年第2期86-91,共6页
Enantiomers (R (+) and S(-)), RS-racemate mixture of enantiomers) of malic acid C4H605 have been (double compound) and (R + S) -conglomerate (mechanical investigated by means of X-ray diffractometry and ... Enantiomers (R (+) and S(-)), RS-racemate mixture of enantiomers) of malic acid C4H605 have been (double compound) and (R + S) -conglomerate (mechanical investigated by means of X-ray diffractometry and high tern- perature X-ray diffraction method. The RS-racemate was found to be able to form three polymorphic modifications, which we denominated as M1 (monoclinic, space group P21/c), M2 (monoclinic, space group Cc), and Tc (triclinic, space group P-l ), the latter modification having been unknown before. Modification Tc was also described, and its X- ray diffraction characteristics, including interplanar spacings d, hkl indices, unit cell parameters, were defined. In addi- tion, X-ray diffraction characteristics for both reported earlier M1 and M2 monoclinic polymorphic modifications were measured with higher accuracy. The ability of RS-racemate to form one of the above three modifications (MI, M2, and Tc) or their mixtures containing various proportions and combinations of the components (M1 + M2, M1 + Tc, or M2 + Tc) was found to depend on the type of crystallization medium (a melt, aqueous medium, ethanol or acetone solu- tion), crystallization rate (from 2--3 minutes to 4 months), and crystallization temperature. Heating S-enantiomer and M1 RS-racemate up to their respective melting points (100 ℃ and 124 ℃, correspondingly) only made them undergo thermal deformations, while heating (R + S) -conglomerate in the temperature range of 96--110 ℃ resulted in its homogenization to form M2 RS-racemate, which, near the melting point (118 ℃), namely, in the range of 112-116 ℃, was transformed into MI RS-racemate. Keywords: polvmorDhism; racemic, chiral 展开更多
关键词 POLYMORPHISM RACEMIC CHIRAL
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300万台
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《家电大视野》 2011年第12期20-20,共1页
苹果iPad3将于2012年3月上市,首批300万台近期出货,数量优于预期。日前外界传出苹果因全球景气欠佳,将10~12月iPad2订单下调25%.
关键词 苹果体 IPAD3 分辨率 处理器 笔记本电脑
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Neural network and principal component regression in non-destructive soluble solids content assessment:a comparison 被引量:4
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作者 Kim-seng CHIA Herlina ABDUL RAHIM Ruzairi ABDUL RAHIM 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2012年第2期145-151,共7页
Visible and near infrared spectroscopy is a non-destructive,green,and rapid technology that can be utilized to estimate the components of interest without conditioning it,as compared with classical analytical methods.... Visible and near infrared spectroscopy is a non-destructive,green,and rapid technology that can be utilized to estimate the components of interest without conditioning it,as compared with classical analytical methods.The objective of this paper is to compare the performance of artificial neural network(ANN)(a nonlinear model)and principal component regression(PCR)(a linear model)based on visible and shortwave near infrared(VIS-SWNIR)(400-1000 nm)spectra in the non-destructive soluble solids content measurement of an apple.First,we used multiplicative scattering correction to pre-process the spectral data.Second,PCR was applied to estimate the optimal number of input variables.Third,the input variables with an optimal amount were used as the inputs of both multiple linear regression and ANN models.The initial weights and the number of hidden neurons were adjusted to optimize the performance of ANN.Findings suggest that the predictive performance of ANN with two hidden neurons outperforms that of PCR. 展开更多
关键词 Artificial neural network (ANN) Principal component regression (PCR) Visible and shortwave nearinfrared (VIS-SWNIR) Spectroscopy APPLE Soluble solids content (SSC)
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