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1.
Mehrabadi Mohammad Hosein Fallah Bahonar Alireza Mirzaei Kamran Molouki Aidin Ghalyanchilangeroudi Arash Ghafouri Seyed Ali Tehrani Farshad Lim Swee Hua Erin 《Tropical animal health and production》2018,50(3):677-682
Tropical Animal Health and Production - Avian influenza virus (AIV) H9N2 subtype is endemic in Iran and causes substantial economic loss to the growing poultry industry within the country. In this... 相似文献
2.
为探究10%乙霉威·腐霉利微粉剂(有效成分质量分数:5%乙霉威,5%腐霉利)在设施黄瓜上施用后的沉积分布特性及残留消解动态,采用PC-3A(S)型激光粉尘仪及粉尘取样片,分别研究了不同设施类型、不同温湿度及不同施药角度下,10%乙霉威·腐霉利微粉剂在设施黄瓜上的沉积分布情况;并于2017年和2018年,分别在北京市进行了该药剂在设施黄瓜叶片和果实中的残留及消解动态试验。结果表明:不同设施类型、不同温度条件下,10%乙霉威·腐霉利微粉剂的沉积分布特性无明显差异,且其有效成分分解率不受温度影响;不同湿度条件下,该微粉剂在黄瓜叶片上的沉积量不同,湿度越大沉积量越多。乙霉威和腐霉利在黄瓜叶片和果实中的消解动态均符合准一级动力学或一级动力学方程,2种药剂在叶片中的半衰期分别为3.2 d和3.0~3.2 d,在果实中的半衰期分别为4.0~4.3 d和3.1~3.8 d。采用10%乙霉威·腐霉利微粉剂,分别按100 g/hm2和150 g/hm2(1.5倍)剂量于黄瓜幼果期施药,最多施药3次,施药间隔期为7 d,距最后一次施药间隔7、10和14 d分别采样,乙霉威在黄瓜果实中的最大残留量为0.88 mg/kg,低于中国国家标准规定的其最大残留限量(MRL)值(5 mg/kg),腐霉利在黄瓜果实中的最大残留量为0.49 mg/kg,也低于其MRL值(2 mg/kg)。该研究结果可为10%乙霉威·腐霉利微粉剂在设施黄瓜上的安全使用提供数据支持。 相似文献
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Several members of the bacterial genus Brenneria are pathogenic on different tree species. Cell-free extracts from the bacterial phytopathogens Brenneria rubrifaciens, B. salicis, and B. nigrifluens induced production of the red pigment rubrifacine in the B. rubrifaciens bruI insertional mutant Br-212. Analysis of the bruI locus identified an adjacent open reading frame, designated bruR, with homology to luxR. High-performance liquid chromatography and mass spectrometry analysis of ethyl acetate extracts from wild-type B. rubrifaciens and Escherichia coli expressing the bruI gene identified two acyl homoserine lactone (AHL) peaks, N-(3-oxohexanoyl)-homoserine lactone (3OC6HSL) and N-hexanoyl-homoserine lactone (C6HSL). Addition of synthetic 3OC6HSL and C6HSL at 10 μM to the bruI mutant, strain Br-212, induced rubrifacine production and the ability to elicit a hypersensitive reaction (HR) in tobacco leaves. Synthetic C6HSL was less effective at inducing pigment production than 3OC6HSL at 10 μM. The bruI mutant Br-212 did not produce detectable AHLs, indicating that C6HSL and 3OC6HSL are the major AHLs produced by this species. The AHLs N-heptanoyl-DL-homoserine lactone (C7HSL), N-octanoyl-DL-homoserine lactone (C8HSL), and N-(3-oxooctanoyl)-DL-homoserine lactone (3OC8HSL) also induced pigment production in Br-212 and restored its ability to elicit an HR in tobacco, suggesting that cross-talk with other bacterial species may be possible. 相似文献
5.
为明确中国华北地区瓜类尖孢镰刀菌Fusarium oxysporum Schl.对咪鲜胺的抗药性现状及抗药突变株的生物学性状,采用菌丝生长速率法,分别测定了采自北京、山东、河北等地未使用过咪鲜胺的112株瓜类尖孢镰刀菌对咪鲜胺的敏感性,并通过药剂驯化的方法获得尖孢镰刀菌抗咪鲜胺突变株。结果表明:咪鲜胺对112株瓜类尖孢镰刀菌的平均EC50值为(0.030 1±0.030 4)μg/mL,菌株频率呈连续单峰曲线分布,未发现敏感性明显下降的亚群体,因此,可将该EC50值作为瓜类尖孢镰刀菌对咪鲜胺的敏感基线。药剂驯化共获得7株抗咪鲜胺突变株,其抗性倍数介于6.2~26.8之间;突变株在菌丝生长速率、菌丝干重和致病力等方面均明显低于亲本菌株,差异显著;仅突变株HG13052701-R1的抗药性可以稳定遗传,其他6株抗咪鲜胺突变株的抗药性均不能稳定遗传。室内交互抗性测定结果表明,咪鲜胺仅与戊唑醇之间有交互抗性,与多菌灵和齅霉灵之间均无交互抗性关系。研究表明,瓜类尖孢镰刀菌在药剂选择压下可以形成抗咪鲜胺群体,具有低等抗药性风险。 相似文献
6.
Ali Hosein Yazdi Vajiheh Zarrinpour Elham Moslemi Mohamad Mahdi Forghani Fard 《Iranian Biomedical Journal》2022,26(4):301
Background:Glioblastoma is the most common primary malignant neoplasm of the central nervous system. Despite progress in diagnosis and treatment, glioblastoma still has a poor prognosis. This study aimed to examine whether a signature of three candidate miRNAs (i.e. hsa-let-7c-5p, hsa-miR-206-5p, and hsa-miR-1909-5p) can be used as a diagnostic biomarker for distinguishing glioblastoma from healthy brain tissues. Methods:In this study, 50 FFPE glioblastoma tissue samples and 50 healthy tissue samples adjacent to tumor were included. The expression of each candidate miRNA (i.e. hsa-let-7c-5p, hsa-miR-206-5p, and hsa-miR-1909-5p) was measured using RT-qPCR. To show the roles of each miRNA and their biological effects on glioblastoma development and clinicopathological characteristics, in silico tools were used. ROC curves were performed to assess the diagnostic accuracy of each miRNA. Results:Based on the results, hsa-let-7c-5p and hsa-miR-206-5p were downregulated, while hsa-miR-1909-5p was upregulated in glioblastoma tumors compared to healthy samples. No association was detected between the expression of each candidate miRNA and sex. Except for hsa-let-7c-5p, other miRNAs did not correlate with age status. ROC curve analysis indicated that the signature of candidate miRNAs is a potential biomarker distinguishing between glioblastoma and healthy samples. Only hsa-miR-206-5p suggested the association with poor prognosis in glioblastoma patients. Conclusion:Our findings revealed that the signature of three miRNAs is capable of distinguishing glioblastoma tumor and healthy tissues. These results are beneficial for the clinical management of glioblastoma patients.Key Words: Inflammation, Gastric cancer, Gene expression, Pattern recognition receptors, RNA-seq 相似文献
7.
Expression profiling of transgenes (Cry1Ac and Cry2A) in cotton genotypes under different genetic backgrounds
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Kashif NOOR Hafiza Masooma Naseer CHEEMA Asif Ali KHAN Rao Sohail Ahmad KHAN 《农业科学学报》2022,21(10):2818-2832
Transgenic cotton carrying the CrylAc gene has revolutionized insect pest control since its adoption,although the development of resistance in insect pests has reduced its efficacy.After 10 years of cultivating Bacillus thuringiensis(Bt) cotton with a single Cry1 Ac gene,growers are on the verge of adopting Bt cotton that carries the double gene(Cry1 Ac+Cry2 A) due to its better effectiveness against insect pests.Thus,the current study was designed to evaluate the role of each gene in the effect... 相似文献
8.
Emin Zeki Başkent Ali İhsan Kadıoğulları 《Scandinavian Journal of Forest Research》2014,29(7):121-131
Decision support systems (DSSs) are indispensable tools in preparing a forest management plan for a better combination of multiple forest values. This study attempted to develop and explain a stand-based forest management DSS (Ecosystem-based multiple-use forest planning [ETÇAP]) comprising a traditional simulation, linear programming (LP), metaheuristics and geographic information system. The model consists of five submodels; traditional management approach to handle inventory data, an empirical growth and yield model, a simulation to conceptualize management actions, a LP technique to optimize resource allocation and a simulated annealing approach to directly create a spatially feasible harvest schedule. The ETÇAP model has been implemented in a comparative two case study areas; Denizli–Honaz and Akseki–Ibrad?. Both simulation and optimization models outperformed to the traditional management plan. The periodical change of growing stock, allowable cuts, carbon sequestration and water production are used as performance indicators. The results showed that more amount of wood could be harvested over time compared to traditional level of harvesting. It could be concluded that various management strategies allowed managers to stimulate more decision options for better outputs through intertemporal trade-offs of management interventions as the model provided tools to quantify forest dynamics over time and space. Challenges exist to establish the functional relationships between forest structure and values for better quantification and integration into the management plans. 相似文献
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The present investigation was conducted to assess the ameliorative effects of foliar‐applied trehalose on growth, photosynthetic attributes, water relation parameters and oxidative defence mechanism in two maize cultivars under field water deficit conditions. Various components of the experiment comprised two maize cultivars (EV‐1098 and Agaiti‐2002), two water‐stress levels (irrigation after 2 weeks and irrigation after 3 weeks during the entire period of growth), and two levels of trehalose (0 and 30 mm ) and four replicates of each treatment. Water stress significantly reduced the plant biomass production, photosynthetic attributes and water relation parameters in both maize cultivars. In contrast, water stress considerably increased the leaf malondialdehyde (MDA) contents, the activities of antioxidant enzymes such as peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT), and the levels of non‐enzymatic compounds such as ascorbic acid and tocopherols. In contrast, water stress caused a marked reduction in leaf phenolic contents. Foliar‐applied trehalose significantly increased plant biomass production, and improved some key photosynthetic attributes and plant–water relation parameters. The ameliorative effect of exogenously applied trehalose was also observed on the activities of some key antioxidant enzymes (POD and CAT) and non‐enzymatic compounds (tocopherols and phenolics). Overall, exogenously applied trehalose considerably improved drought tolerance of maize plants by up‐regulating photosynthetic and water relation attributes as well as antioxidant defence mechanism. 相似文献
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