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麦根腐平脐蠕孢是一种可以引起多种植物病害的病原真菌,广泛分布于世界各地,对全世界的禾谷类作物生产带来了不可估量的损失。子囊菌交配型基因具有一定的广泛性,其编码的产物是调控子囊菌有性生殖的重要转录因子。为了对河南、安徽小麦田分离获得的麦根腐平脐蠕孢群体的MAT基因型进行探索,对在河南、安徽两省不同地区分离获得33株麦根腐平脐蠕孢菌株,利用麦根腐平脐蠕孢菌的MAT特异性引物进行基因型检测,并对不同交配型代表菌株进行生长形态、孢子形态观察和致病力测定,对麦根腐平脐蠕孢菌 MAT-2基因进行了系统发育分析。结果表明,河南、安徽两省存在两种MAT基因型的麦根腐平脐蠕孢群体,含有 MAT-2基因的菌株21株,含 MAT-1基因的菌株12株,比例为7∶4（ MAT-2∶ MAT-1）。两种交配型菌株的生长形态、孢子形态和致病力无显著差异,整体分析结果与物种的分子系统学分析表现出来的亲缘关系基本一致。 相似文献
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Twenty-four red deer hinds with their calves were released on to a newly established pure red clover sward and, 2 days later, red staining of the tail, perineum and hocks was observed. This was presumed to be of urinary origin. Observation of micturition showed that when urine was passed, it was a normal straw colour but it turned scarlet-red about 1 hour after exposure to air. Midstream urine remained the normal colour when held under a pure nitrogen atmosphere immediately after micturition, but it turned red when held in air in the dark, suggesting that the colour change was due to an oxidative rather than a photosensitive reaction. All deer grazing red clover were affected but this did not occur in deer grazing ryegrass/white clover swards. No adverse effects were observed in the deer grazing the red clover, and calf growth was significantly higher than on ryegrass/white clover, suggesting that the red urine had no effect on health or productivity. Blood and urine analyses showed no signs of haemolysis, haematuria or haemoglobinuria. Preliminary chemical analyses suggest that the compounds involved are not those found in the urine of sheep grazing oestrogenic clover. The nature of the compounds have yet to be determined. 相似文献
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Creighton M. Litton Christian P. Giardina Gregory P. Asner 《Soil biology & biochemistry》2011,43(11):2315-2323
Soil-surface CO2 efflux (FS; ‘soil respiration’) accounts for ≥50% of the CO2 released annually by the terrestrial biosphere to the atmosphere, and the magnitude and variability of this flux are likely to be sensitive to climate change. We measured FS in nine permanent plots along a 5.2 °C mean annual temperature (MAT) gradient (13-18.2 °C) in Hawaiian tropical montane wet forests where substrate type and age, soil type, soil water balance, disturbance history, and canopy vegetation are constant. The objectives of this study were to quantify how the (i) magnitude, (ii) plot-level spatial variability, and (iii) plot-level diel variability of FS vary with MAT. To address the first objective, annual FS budgets were constructed by measuring instantaneous FS monthly in all plots for one year. For the second objective, we compared plot-level mean instantaneous FS in six plots derived from 8 versus 16 measurements, and conducted a power analysis to determine adequate sample sizes. For the third objective, we measured instantaneous FS hourly for 24 h in three plots (cool, intermediate and warm MATs). The magnitude of annual FS and the spatial variability of plot-level instantaneous FS increased linearly with MAT, likely due to concomitant increases in stand productivity. Mean plot-level instantaneous FS from 8 versus 16 measurements per plot yielded statistically similar patterns. The number of samples required to estimate plot-level instantaneous FS within 10% and 20% of the actual mean increased with MAT. In two of three plots examined, diel variability in instantaneous FS was significantly correlated with soil temperature but minimal diel fluctuations in soil temperature (<0.6 °C) resulted in minimal diel variability in FS. Our results suggest that as MAT increases in tropical montane wet forests, FS will increase and become more spatially variable if ecosystem characteristics and functioning undergo concurrent changes as measured along this gradient. However, diel variation in FS will remain a minor component of overall plot-level variation. 相似文献
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[目的]建立一种检测8-羟基喹啉铜的方法.[方法]采用自制合成的吖啶酮衍生物10-甲基-3-硝基-吖啶酮(MAT)作为增强型荧光信号探针,建立8-羟基喹啉铜的测定方法.[结果]在最佳条件下荧光增强值与8-羟基喹啉铜的浓度在5×10-9 ～5 ×10-5 mol/L范围内成良好的线性关系,检测限为6×10-10 mol/L.[结论]该方法灵敏度高、检测范围宽,结果令人满意,可用于实际样品中8-羟基喹啉铜含量的直接测定. 相似文献
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本文对5种弓形虫血清IgG抗体检测方法进行比较评价。5种方法平行检测了80份血清,比较各检测方法的阳性检出率,敏感性,特异性,符合率及Youden指数。结果经配对2检验,ELISA-200,IHA,MAT,SPA-ELISA 4种方法在阳性检出率、平行检测结果之间无显著性差异(P<0.05)。ELISA-200敏感性、特异性和符合率均高于90%,Youden指数(0.85)显著高于其他方法(P<0.05)。IHA,MAT,SPA-ELISA 3种方法各指标处于中等水平,各有适合的检测环境。ELISA-100与其他四种方法在检测结果上差异极显著(P<0.01),特异性(38.3%)、符合率(58.75%)及Youden指数(0.383)都显著低于其他方法。 相似文献
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本研究旨在通过构建西农萨能羊脂肪酸合酶(FASN)基因乙酰/丙二酸单酰基转移酶(MAT)区域的重组腺病毒载体,为研究其在奶山羊乳腺上皮细胞中过表达以及功能和作用机制做准备。根据GenBank收录的西农萨能羊MAT序列设计引物,PCR扩增并克隆测序。将目的基因连接到穿梭载体pAdTrack/CMV上并线性化后,转化含有腺病毒骨架载体pAdEasyⅠ的E.coli Bj5183感受态细胞进行同源重组,得到重组腺病毒质粒pAd-MAT-HIS,并用PacⅠ酶切鉴定,将经过PacⅠ线性化的pAd-MAT-HIS转染HEK 293细胞进行病毒包装和扩增,用LaSRT法测定病毒滴度。将本次克隆的MAT序列与GenBank收录的山羊序列对比发现,在601bp处碱基由G转变为A,导致氨基酸序列由丙氨酸(Ala)201转变为苏氨酸(Thr)201。酶切鉴定、绿色荧光蛋白观察、PCR及Western blot检测均证明,重组腺病毒质粒构建成功,病毒滴度为2×109 PFU.mL-1。本研究成功构建了重组腺病毒pAdEasy-MAT-HIS。 相似文献
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高速离心分离游离的苦参碱(MAT)和氧化苦参碱(OMT),应用HPLC法测定MAT和OMT的浓度并计算包封率,建立苦参碱类生物碱传递体包封率的HPLC测定方法。结果显示,MAT进样量在0.074~0.370μg/mL、OMT进样量在0.263~1.315μg/mL时,两者峰面积与进样量具有良好的线性关系。在高加样量0.148μg/mL和低加样量0.111μg/mL下,MAT的平均加样回收率分别为100.2%和98.2%,RSD分别为1.07%和2.38%;OMT的平均加样回收率分别为98.3%和100.2%,RSD分别为0.75%和0.66%。制剂中MAT和OMT的包封率分别为80.43%和74.70%,RSD分别为1.03%和1.11%。建立的方法适用于苦参碱类生物碱传递体包封率的测定。 相似文献
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对采用不同分离方法获得的40个冬虫夏草（Ophiocordyceps sinensis）无性型菌株进行交配型基因MAT1-2-1的PCR特异扩增,并随机取其中7个拼接好的MAT1-2-1的碱基序列,与4个来自GenBank 数据在内的共11个样品构建了系统发育树。结果表明,采自青海的7个供试菌株,连同GenBank中来自青海的菌株（FJ654176）共同组成了一大类群,而GenBank中其他地区的菌株则聚成另外的类群;随机分离得到的10个单子囊孢子菌株全部含有MAT1-2-1基因, MAT1-1: MAT1-2未见按4:4进行分离,提示冬虫夏草极有可能是同宗配型。 相似文献