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瓷珠保存法定量制备单核细胞增生李斯特菌质控菌株 认领
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作者 耿冬青 《肉类工业》 2020年第7期45-47,共3页
为了获得食品微生物实验室操作方便、使用便捷的菌种保存方式,利用瓷珠保存法制备单核细胞增生李斯特菌质控样品。通过室内复现性检测、储藏稳定性及活力的检验证明,此法制备的质控样品具有均匀性、储藏稳定性,能满足质控样品使用的要求... 为了获得食品微生物实验室操作方便、使用便捷的菌种保存方式,利用瓷珠保存法制备单核细胞增生李斯特菌质控样品。通过室内复现性检测、储藏稳定性及活力的检验证明,此法制备的质控样品具有均匀性、储藏稳定性,能满足质控样品使用的要求,可以用于食品微生物日常检验工作中的阳性对照试验。 展开更多
关键词 瓷珠保存法 定量 质控菌株
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Defying the Court:A Spatial Analysis of the Central–Local Government Relationship During the Boxer Uprising(1900–1901) 认领
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作者 Fang Liu 《复旦人文社会科学论丛:英文版》 2020年第2期277-300,共24页
The central–local government relationship has always been an important topic for political research of the Late Qing period.Former researchers focused mainly on political systems,finding historical archives to explai... The central–local government relationship has always been an important topic for political research of the Late Qing period.Former researchers focused mainly on political systems,finding historical archives to explain how the Qing Court decentralized or centralized its power.These approaches fail to consider how local officials in fact reacted to central command.This research is an attempt to apply the social science method to a classical historical study.I firstly examine the various political decisions of governors when they were faced with a series of big events during the Boxer Uprising(1900–1901).After arranging them using strict criteria,I will conduct spatial and structural analysis on their diversity,and furthermore explore the internal and external influencing factors.Statistics indicate that governors of coastal provinces and of the provinces along the Yangtze River were more likely to express their opinions to the Qing court,while the North and Northeastern provinces tended to obey the central orders.Regional differences mainly have a positive correlation with provincial structural factors,such as revenue and relations with foreign powers.The correlations are also determined by personal political experience and resources of governors. 展开更多
关键词 The central–local government relationship BOXERS Governors Regional diversity Quantitative analysis
Value of metabolic parameters in distinguishing primary mediastinal lymphomas from thymic epithelial tumors 认领
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作者 Lei Zhu Xiaofeng Li +5 位作者 Jian Wang Qiang Fu Jianjing Liu Wenchao Ma Wengui Xu Wei Chen 《癌症生物学与医学:英文版》 SCIE CAS CSCD 2020年第2期468-477,共10页
Objective:A high rate of unnecessary thymectomies has been reported.This study aimed to distinguish primary mediastinal lymphomas(PMLs)from thymic epithelial tumors(TETs)by evaluating volumetric and metabolic paramete... Objective:A high rate of unnecessary thymectomies has been reported.This study aimed to distinguish primary mediastinal lymphomas(PMLs)from thymic epithelial tumors(TETs)by evaluating volumetric and metabolic parameters with l8F-FDG PET/CT.Methods:A total of 136 patients who were pathologically diagnosed with TETs or PMLs were enrolled,and 18F-FDG PET/CT was performed before therapy.Volumetric parameters,including the mean SUV(SUVmean),metabolic tumor volume(MTV),total lesion glycolysis(TLG),and SUVmax,were determined and compared between the 2 subtypes.The diagnostic performance of these parameters was evaluated with receiver operating characteristic(ROC)curve analysis.Results:All parameters significantly differed between patients with PMLs and TETs.Patients with lymphomas were younger and had higher SUVmean,SUVmax,TLG,and MTV values than patients with TETs.The MTV and TLG values had similar diagnostic performance.ROC analysis indicated that the areas under the curves of the SUVmean and SUVmax values performed similarly(approximately 0.76)in differentiating patients with PMLs from TETs,and both values were better than the MTV and TLG values.When age was included with the SUVmax in differentiating TETs from PMLs,the AUC was 0.91,and the sensitivity and specificity increased to 80%and 93%,respectively.Conclusions:The SUVmax and volumetric parameters of 18F-FDG PET/CT can be used to distinguish patients with PMLs versus TETs,and thus may aid in preventing unnecessary thymectomies or other invasive operations. 展开更多
关键词 FDG PET-CT LYMPHOMA metabolic tumor burden quantitative evaluation thymic epithelial tumors
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Flue Gas Monitoring System With Empirically-Trained Dictionary 认领
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作者 Hui Cao Yajie Yu +1 位作者 Panpan Zhang Yanxia Wang 《自动化学报:英文版》 EI CSCD 2020年第2期606-616,共11页
The monitoring of flue gas of the thermal power plants is of great significance in energy conservation and environmental protection.Spectral technique has been widely used in the gas monitoring system for predicting t... The monitoring of flue gas of the thermal power plants is of great significance in energy conservation and environmental protection.Spectral technique has been widely used in the gas monitoring system for predicting the concentrations of specific gas components.This paper proposes flue gas monitoring system with empirically-trained dictionary(ETD)to deal with the complexity and biases brought by the uninformative spectral data.Firstly,ETD is extracted from the raw spectral data by an alternative optimization between the sparse coding stage and the dictionary update stage to minimize the error of sparse representation.D1,D2 and D3 are three types of ETD obtained by different methods.Then,the predictive model of component concentration is constructed on the ETD.In the experiments,two real flue gas spectral datasets are collected and the proposed method combined with the partial least squares,the background propagation neural network and the support vector machines are performed.Moreover,the optimal parameters are chosen according to the 10-fold root-mean-square error of cross validation.The experimental results demonstrate that the proposed method can be used for quantitative analysis effectively and ETD can be applied to the gas monitoring systems. 展开更多
关键词 DICTIONARY LEARNING empirically-trained dictionaty(ETD) FLUE gas monitoring system QUANTITATIVE analysis
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Genetic bases of source-, sink-, and yield-related traits revealed by genome-wide association study in Xian rice 认领
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作者 Yun Wang Yunlong Pang +4 位作者 Kai Chen Laiyuan Zhai Congcong Shen Shu Wang Jianlong Xu 《作物学报:英文版》 SCIE CAS CSCD 2020年第1期119-131,共13页
The source-sink relationship determines the ultimate grain yield.We investigated the genetic basis of the relationship between source and sink and yield potential in rice.In two environments,we identified quantitative... The source-sink relationship determines the ultimate grain yield.We investigated the genetic basis of the relationship between source and sink and yield potential in rice.In two environments,we identified quantitative trait loci(QTL)associated with sink capacity(total spikelet number per panicle and thousand-grain weight),source leaf(flag leaf length,flag leaf width and flag leaf area),source-sink relationship(total spikelet number to flag leaf area ratio)and yield-related traits(filled grain number per panicle,panicle number per plant,grain yield per plant,biomass per plant,and harvest index)by genome-wide association analysis using 272 Xian(indica)accessions.The panel showed substantial variation for all traits in the two environments and revealed complex phenotypic correlations.A total of 70 QTL influencing the 11 traits were identified using 469,377 high-quality SNP markers.Five QTL were detected consistently in four chromosomal regions in both environments.Five QTL clusters simultaneously affected source,sink,source–sink relationship,and grain yield traits,probably explaining the genetic basis of significant correlations of grain yield with source and sink traits.We selected 24 candidate genes in the four consistent QTL regions by identifying linkage disequilibrium(LD)blocks associated with significant SNPs and performing haplotype analysis.The genes included one cloned gene(NOG1)and three newly identified QTL(qHI6,qTGW7,and qFLA8).These results provide a theoretical basis for high-yield rice breeding by increasing and balancing source–sink relationships using marker-assisted selection. 展开更多
关键词 RICE GWAS Source–sink relationship Quantitative TRAIT loci/locus(QTL) Candidate gene
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标准流量积算仪的研究与实现 认领
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作者 臧振胜 《仪器仪表用户》 2020年第5期22-24,共3页
介绍了标准流量积算仪的基本功能,从硬件构成、仪表接口和控制逻辑几个方面,详细阐述了标准流量积算仪在计量检定和校准装置中的应用。在音速喷嘴气流量标准装置、钟罩式气体流量标准装置、静动态质量法水流量标准装置、静动态容积法水... 介绍了标准流量积算仪的基本功能,从硬件构成、仪表接口和控制逻辑几个方面,详细阐述了标准流量积算仪在计量检定和校准装置中的应用。在音速喷嘴气流量标准装置、钟罩式气体流量标准装置、静动态质量法水流量标准装置、静动态容积法水流量标准装置和标准体积管流量标准装置中,可以准确地采集标准计量时间、标准表和被检表的脉冲频率、脉冲累积量以及被检表的电流信号值。通过面板控制,DI端子触发和串口命令3种方式实现仪表的启停控制,以实现智能化采集,并根据数值大小调整小数点的显示位数。经测试比较,标准流量积算仪可以稳定高效地作为标准装置的计量仪表,达到了预期的设计效果。 展开更多
关键词 积算仪 脉冲 电流 晶振 时间 定量 热电阻
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电子舌识别技术对腌制黄瓜调料的定量化分析 认领
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作者 刘韵 《中国调味品》 CAS 北大核心 2020年第3期140-144,共5页
采用一种基于电子舌识别技术的方法对腌制黄瓜中盐、总酸、还原糖和乳酸钙进行定量分析。采用PLS分析和BP-ANN分析对数据进行处理,建立并对比了两种预测模型。结果表明,PLS模型和BP-ANN模型均具有较好的预测能力,相关系数(R^2)均在0.9... 采用一种基于电子舌识别技术的方法对腌制黄瓜中盐、总酸、还原糖和乳酸钙进行定量分析。采用PLS分析和BP-ANN分析对数据进行处理,建立并对比了两种预测模型。结果表明,PLS模型和BP-ANN模型均具有较好的预测能力,相关系数(R^2)均在0.9以上。对于盐和乳酸钙,两种模型适用性相似;对于总酸,BP-ANN模型优于PLS模型;对于还原糖,PLS模型优于BP-ANN模型。该研究为电子舌识别技术在腌制黄瓜调料定量化分析中应用的可行性提供了理论依据。 展开更多
关键词 电子舌 腌制黄瓜 定量 调料
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短空间二维傅里叶变换对铝板的损伤定量研究 认领
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作者 常俊杰 万陶磊 钟海鹰 《电子测量与仪器学报》 CSCD 北大核心 2020年第6期102-108,共7页
针对Lamb波对铝板损伤定量难的问题,使用短空间二维傅里叶变换的方法对其进行了研究。首先,使用空气耦合超声在铝板中激励Lamb波并进行线性扫查获取其时间-空间波场信号;然后,对信号进行短空间二维傅里叶变换获取扫查区域的Lamb波空间-... 针对Lamb波对铝板损伤定量难的问题,使用短空间二维傅里叶变换的方法对其进行了研究。首先,使用空气耦合超声在铝板中激励Lamb波并进行线性扫查获取其时间-空间波场信号;然后,对信号进行短空间二维傅里叶变换获取扫查区域的Lamb波空间-波数曲线,并从中得到损伤的位置、长度和深度信息;最后,根据相速度-频厚积曲线反推出损伤的深度。结果表明,所提方法能够同时对扫查区域的板厚以及损伤的位置、长度和深度进行评估。其中,板厚定量误差最大为5.50%,损伤长度和深度的定量误差最大分别为6.00%和6.67%。 展开更多
关键词 短空间傅里叶变换 LAMB波 空气耦合超声 深度 定量 定位
剪切波弹性成像技术在肌肉评价中的应用现状 认领
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作者 尚怡然 陈胜江 《实用临床医学(江西)》 CAS 2020年第6期100-103,共4页
剪切波弹性成像(SWE)技术在甲状腺、乳腺、肝脏等方面应用已久,与传统二维超声相比,SWE技术可提供软组织硬度的定量信息。近年来,SWE在骨骼肌系统方面的应用越来越多。文章综述SWE技术在肌肉评价中的可行性、影响因素及应用方面的研究... 剪切波弹性成像(SWE)技术在甲状腺、乳腺、肝脏等方面应用已久,与传统二维超声相比,SWE技术可提供软组织硬度的定量信息。近年来,SWE在骨骼肌系统方面的应用越来越多。文章综述SWE技术在肌肉评价中的可行性、影响因素及应用方面的研究进展。 展开更多
关键词 剪切波弹性成像 肌肉评估 定量 综述
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桑蚕丝制品中增重剂的定性和定量测试 认领
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作者 郑福尔 蔡涛 +2 位作者 吴秋兰 邓梦颖 林春香 《毛纺科技》 CAS 北大核心 2020年第2期63-67,共5页
桑蚕丝制品中增重剂的定性和定量测试对规范和控制桑蚕丝品质具有重要的意义。文章对增重前后桑蚕丝制品及增重剂进行红外光谱(FTIR)表征和热稳定性测定,分析桑蚕丝纤维增重前后结构的变化以及桑蚕丝制品和增重剂的特征温度及该温度区... 桑蚕丝制品中增重剂的定性和定量测试对规范和控制桑蚕丝品质具有重要的意义。文章对增重前后桑蚕丝制品及增重剂进行红外光谱(FTIR)表征和热稳定性测定,分析桑蚕丝纤维增重前后结构的变化以及桑蚕丝制品和增重剂的特征温度及该温度区间所对应的质量损失率,并用比例法计算桑蚕丝制品中增重剂的含量。结果表明:当桑蚕丝制品中各组分的失重特征温度存在明显区分和差异时,可以用组分的失重特征温度来定性测试增重后桑蚕丝制品中的各组分;桑蚕丝制品中增重剂和桑蚕丝的失重特征温度区间是互不重叠、相对独立的,且失重过程与各组分单独失重特征温度区间相同,因此采用比例法计算桑蚕丝制品中增重剂的含量具有可行性。 展开更多
关键词 桑蚕丝制品 增重剂 定性 定量 热重法 比例法
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Pollen-based Holocene quantitative temperature reconstruction on the eastern Tibetan Plateau using a comprehensive method framework 认领
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作者 Chen LIANG Yan ZHAO +5 位作者 Feng QIN Zhuo ZHENG Xiayun XIAO Chunmei MA Huan LI Wenwei ZHAO 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2020年第8期1144-1160,共17页
Quantitative climate reconstruction on long timescales can provide important insights for understanding the climate variability and providing valuable data for simulations. Unfortunately, the credibility of some attem... Quantitative climate reconstruction on long timescales can provide important insights for understanding the climate variability and providing valuable data for simulations. Unfortunately, the credibility of some attempts was hampered by incomplete reconstruction procedures. We here establish a comprehensive framework resting on high-quality Chinese modern pollen database, including modern pollen data screening, calibration set selection, major climate factor analysis, appropriate model selection, strict statistical assessment of results and ecological interpretation. The application of this framework to three high-resolution pollen records from the eastern Tibetan Plateau allows accurate quantitative inferences of Holocene temperature changes, which is the major control of regional vegetation. The results show that the mean warmest month temperature(MTwa)during the early Holocene was ca. 10.4℃ and reached the highest value at 8.5–6 ka BP(ca. 11℃). The early and mid-Holocene(11–5 ka BP) warmth was followed by 1.2℃ temperature decrease, culminating in the coolest temperatures of the Holocene during the Neoglacial cooling. Superimposing on the general cooling trend, MTwareveals a significant 500-yr periodicity with varying intensities through time, showing that warm(cold) intervals are in phase with solar maxima(minima) periods. This spectral similarity indicates a possible connection of multi-century scale climate fluctuations with solar forcing. 展开更多
关键词 Approach framework of quantitative reconstruction Tibetan Plateau HOLOCENE Temperature changes PERIODICITY
Warming induced changes in wood matter accumulation in tracheid walls of spruce 认领
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作者 Elena BABUSHKINA Dina ZHIRNOVA +1 位作者 Liliana BELOKOPYTOVA Eugene VAGANOV 《山地科学学报:英文版》 SCIE CSCD 2020年第1期16-30,共15页
The warming-driven increase of the vegetation season length impacts both net productivity and phenology of plants, changing an annual carbon cycle of terrestrial ecosystems. To evaluate this influence, tree growth alo... The warming-driven increase of the vegetation season length impacts both net productivity and phenology of plants, changing an annual carbon cycle of terrestrial ecosystems. To evaluate this influence, tree growth along the temperature gradients can be investigated on various organization levels, beginning from detailed climatic records in xylem cells’ number and morphometric parameters. In this study, the Borus Ridge of the Western Sayan Mountains(South Siberia) was considered as a forest area under rapid climate change caused by massive Sayano-Shushenskoe reservoir. Several parameters of the xylem anatomical structure in Siberian spruce(Picea obovata Ledeb.)were derived from normalized tracheidograms of cell radial diameter and cell wall thickness and analyzed during 50 years across elevational gradient(at 520,960, and 1320 m a.s.l.). On the regional scale, the main warming by 0.42°C per decade occurs during cold period(November–March). Construction of the reservoir accelerated local warming substantially since 1980, when abrupt shift of the cold season temperature by 2.6°C occurred. It led to the vegetation season beginning 3-6 days earlier and ending 4-10 day later with more stable summer heat supply. Two spatial patterns were found in climatic response of maximal cell wall thickness:(1)temperature has maximal impact during 21-day period, and its seasonality shifts with elevation in tune with temperature gradient;(2) response to the date of temperature passing +9.5°C threshold is observed at two higher sites. Climate change yielded significantly bigger early wood spruce tracheids at all sites, but its impact on cell wall deposition process had elevational gradient: maximal wall thickness increased by 7.9% at the treeline, by 18.2% mid-range,and decreased by 4.9% at the lower boundary of spruce growth;normalized total cell wall area increased by 6.2%-6.8% at two higher sites but remained stable at the lowest one. We believe that these patterns are caused by two mechanisms of spruce secondary growth cess 展开更多
关键词 CLIMATE change Sayano-Shushenskoe Reservoir Elevational gradient PICEA obovata Quantitative WOOD anatomy Climate–growth relationship
Quantitative trait loci analysis for root traits in synthetic hexaploid wheat under drought stress conditions 认领
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作者 LIU Rui-xuan WU Fang-kun +8 位作者 YI Xin LIN Yu WANG Zhi-qiang LIU Shi-hang DENG Mei MA Jian WEI Yu-ming ZHENG You-liang LIU Ya-xi 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第8期1947-1960,共14页
Synthetic hexaploid wheat(SHW),possesses numerous genes for drought that can help breeding for drought-tolerant wheat varieties.We evaluated 10 root traits at seedling stage in 111 F9 recombinant inbred lines derived ... Synthetic hexaploid wheat(SHW),possesses numerous genes for drought that can help breeding for drought-tolerant wheat varieties.We evaluated 10 root traits at seedling stage in 111 F9 recombinant inbred lines derived from a F2 population of a SHW line(SHW-L1)and a common wheat line,under normal(NC)and polyethylene glycol-simulated drought stress conditions(DC).We mapped quantitative trait loci(QTLs)for root traits using an enriched high-density genetic map containing 120370 single nucleotide polymorphisms(SNPs),733 diversity arrays technology markers(DArT)and 119 simple sequence repeats(SSRs).With four replicates per treatment,we identified 19 QTLs for root traits under NC and DC,and 12 of them could be consistently detected with three or four replicates.Two novel QTLs for root fresh weight and root diameter under NC explained 9 and 15.7%of the phenotypic variation respectively,and six novel QTLs for root fresh weight,the ratio of root water loss,total root surface area,number of root tips,and number of root forks under DC explained 8.5–14%of the phenotypic variation.Here seven of eight novel QTLs could be consistently detected with more than three replicates.Results provide essential information for fine-mapping QTLs related to drought tolerance that will facilitate breeding drought-tolerant wheat cultivars. 展开更多
关键词 synthetic hexaploid wheat quantitative trait loci drought stress root traits
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Quantitative design of yield components to simulate yield formation for maize in China 认领
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作者 HOU Hai-peng MA Wei +4 位作者 Mehmood Ali NOOR TANG Li-yuan LI Cong-feng DING Zai-song ZHAO Ming 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第3期668-679,共12页
Maize(Zea mays L.) stands prominently as one of the major cereal crops in China as well as in the rest of the world.Therefore,predicting the growth and yield of maize for large areas through yield components under hig... Maize(Zea mays L.) stands prominently as one of the major cereal crops in China as well as in the rest of the world.Therefore,predicting the growth and yield of maize for large areas through yield components under high-yielding environments will help in understanding the process of yield formation and yield potential under different environmental conditions.This accurate early assessment of yield requires accuracy in the formation process of yield components as well.In order to formulate the quantitative design for high yields of maize in China,yield performance parameters of quantitative design for high grain yields were evaluated in this study,by utilizing the yield performance equation with normalization of planting density.Planting density was evaluated by parameters including the maximum leaf area index and the maximum leaf area per plant.Results showed that the variation of the maximum leaf area per plant with varying plant density conformed to the Reciprocal Model,which proved to have excellent prediction with root mean square error(RMSE) value of 5.95%.Yield model estimation depicted that the best optimal maximum leaf area per plant was 0.63 times the potential maximum leaf area per plant of hybrids.Yield performance parameters for different yield levels were quantitatively designed based on the yield performance equation.Through validation of the yield performance model by simulating high yields of spring maize in the Inner Mongolia Autonomous Region and Jilin Province,China,and summer maize in Shandong Province,the yield performance equation showed excellent prediction with the satisfactory mean RMSE value(7.72%) of all the parameters.The present study provides theoretical support for the formulation of quantitative design for sustainable high yield of maize in China,through consideration of planting density normalization in the yield prediction process,providing there is no water and nutrient limitation. 展开更多
关键词 MAIZE YIELD performance PARAMETERS high YIELD YIELD prediction process QUANTITATIVE DESIGN
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Unraveling waterlogging tolerance-related traits with QTL analysis in reciprocal intervarietal introgression lines using genotyping by sequencing in rapeseed(Brassica napus L.) 认领
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作者 DING Xiao-yu XU Jin-song +4 位作者 HUANG He QIAO Xing SHEN Ming-zhen CHENG Yong ZHANG Xue-kun 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第8期1974-1983,共10页
Soil waterlogging is a major environmental stress that suppresses the growth and productivity of rapeseed(Brassica napus L.).Natural genetic variations in waterlogging tolerance(WT)were observed but no QTL mapping has... Soil waterlogging is a major environmental stress that suppresses the growth and productivity of rapeseed(Brassica napus L.).Natural genetic variations in waterlogging tolerance(WT)were observed but no QTL mapping has been done for WT related traits in rapeseed.In this study,QTL associated with three WT related traits including relative root length(RRL),relative hypocotyl length(RHL)and relative fresh weight(RFW)were dissected using a set of reciprocal introgression lines(ILs)derived from the cross GH01×ZS9,which showed significant difference in WT.Genotyping-by-sequencing(GBS)of the populations were performed,totally 1468 and 1450 binned SNPs were identified for GIL(GH01 as the recurrent parent)and ZIL(ZS9 as the recurrent parent)population,respectively.A total of 66 distinct QTLs for WT at the seedling establishment stage including 31 for RRL,17 for RHL and 18 for RFW were detected.Among the 66 QTLs,20(29.4%)QTLs were detected in both genetic backgrounds and then they were integrated into six QTL clusters,which can be targeted in rapeseed breeding for improvement of WT through marker-assisted selection(MAS).Based on the physical positions of SNPs and the functional annotation of the Arabidopsis thaliana genome,56 genes within the six QTL cluster regions were selected as preliminary candidate genes,then the resequencing and transcriptome information about parents were applied to narrow the extent of candidate genes.Twelve genes were determined as candidates for the six QTL clusters,some of them involved in RNA/protein degradation,most of them involved in oxidation-reduction process.These findings provided genetic resources,candidate genes to address the urgent demand of improving WT in rapeseed breeding. 展开更多
关键词 Brassica napus candidate genes marker-assisted selection quantitative trait loci mapping waterlogging tolerance
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Synthesis, Characterization, and Antifungal Evaluation of Thiolactomycin Derivatives 认领
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作者 Pei Lv Yiliang Chen +3 位作者 Dawei Wang Xiangwei Wu Qing XLi Rimao Hua 《工程(英文)》 SCIE EI 2020年第5期560-568,共9页
5-Substituted benzylidene 3-acylthiotetronic acids are antifungal.A series of 3-acylthiotetronic acid derivatives with varying substitutions at the 5-position were designed,synthesized,and characterized,based on the b... 5-Substituted benzylidene 3-acylthiotetronic acids are antifungal.A series of 3-acylthiotetronic acid derivatives with varying substitutions at the 5-position were designed,synthesized,and characterized,based on the binding pose of 3-acyl thiolactone with the protein C171Q KasA.Fungicidal activities of these compounds were screened against Valsa Mali,Curvularia lunata,Fusarium graminearum,and Fusarium oxysporum f.sp.lycopersici.Most target compounds exhibited excellent fungicidal activities against target fungi at the concentration of 50μg·mL-1.Compounds 11c and 11i displayed the highest activity with a broad spectrum.The median effective concentration(EC50)values of 11c and 11i were 1.9–10.7 and 3.1–7.8μg·mL-1,respectively,against the tested fungi,while the EC50 values of the fungicides azoxystrobin,carbendazim,and fluopyram were respectively 0.30,4.22,and>50μg·mL-1 against V.Mali;6.7,41.7,and 0.18μg·mL-1 against C.lunata;22.4,0.42,and 0.43μg·mL-1 against F.graminearum;and 4.3,0.12,and>50μg·mL-1 against F.oxysporum f.sp.lycopersici.The structures and activities of the target compounds against C.lunata were analyzed to obtain a statistically significant comparative molecular field analysis(CoMFA)model with high prediction abilities(q2=0.9816,r2=0.8060),and its reliability was verified.The different substituents on the benzylidene at the 5-position had significant effects on the activity,while the introduction of a halogen atom at the benzene ring of benzylidene was able to improve the activity against the tested fungi. 展开更多
关键词 3-Acylthiotetronic acid FUNGICIDE Quantitative structure-activity relationship Antifungal activity
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数字化色觉定量检查研究 认领
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作者 李太东 陈丹婷 施伟 《中国现代医生》 2020年第14期70-73,F0003,共5页
目的 研究不同设计方案对计算机数字化色觉定量测试的准确度,寻找可行性解决方案.方法 采用基于瑞利匹配法则设计的A、B、C三种不同方案,对165例色觉异常和20例色觉正常学生进行R、G值测量.结果 方案A基本能检出色觉正常者与异常者,B、... 目的 研究不同设计方案对计算机数字化色觉定量测试的准确度,寻找可行性解决方案.方法 采用基于瑞利匹配法则设计的A、B、C三种不同方案,对165例色觉异常和20例色觉正常学生进行R、G值测量.结果 方案A基本能检出色觉正常者与异常者,B、C方案检出色觉异常的比例最大,且能初步确定色觉异常程度(P<0.01).结论 数字化色觉定量检查具有可行性,C方案能初步检测色觉异常轻重程度;较低亮度范围内的样本黄色可以使色觉异常检出比率提高且稳定. 展开更多
关键词 色觉异常 定量 色觉检查 瑞利匹配法则 计算机辅助
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防老剂TMQ有效成分的含量分析 认领
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作者 李海燕 岳敏 《橡胶科技》 2020年第3期168-170,共3页
分别采用GB/T 8826—2011中高效液相色谱法定量分析、红外光谱法定性分析和薄层色谱法半定量分析防老剂TMQ有效成分二聚体含量。结果表明:高效液相色谱定量采用面积归一法进行数据处理分析防老剂TMQ的有效成分二聚体含量时具有一定的局... 分别采用GB/T 8826—2011中高效液相色谱法定量分析、红外光谱法定性分析和薄层色谱法半定量分析防老剂TMQ有效成分二聚体含量。结果表明:高效液相色谱定量采用面积归一法进行数据处理分析防老剂TMQ的有效成分二聚体含量时具有一定的局限性,建议采用内标法或外标法进行定量分析;对于有疑问的分析结果,可以结合薄层色谱法半定量结果进行分析。 展开更多
关键词 防老剂TMQ 有效成分 二聚体含量 定性 定量 高效液相色谱 红外光谱 薄层色谱
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High-resolution linkage and quantitative trait locus mapping using an interspecific cross between Argopecten irradians irradians(♀) and A. purpuratus (♂) 认领
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作者 Junxia Mao Qifan Zeng +5 位作者 Zujing Yang Haoyuan Pan Lijie Yao Zhenmin Bao Chunde Wang Shi Wang 《海洋生命科学与技术(英文)》 2020年第2期123-134,共12页
The bay scallop and Peruvian scallop are economically important species.Interspecific hybrids of these two scallops outperformed both of their parent species in multiple growth traits but exhibited decreased fertility... The bay scallop and Peruvian scallop are economically important species.Interspecific hybrids of these two scallops outperformed both of their parent species in multiple growth traits but exhibited decreased fertility,which provides good models for the study of heterosis and species divergence.Genetic mapping serves as a chromosomal-level framework to investigate the molecular mechanisms of hybridization and introgression.In this study,high-resolution linkage maps were constructed for the bay and Peruvian scallops with an interspecific hybrid family.The linkage map of the bay scallop covered over 98.9% of the whole genome with 2994 mapped markers and the average marker interval of 0.32 cM.For the Peruvian scallop,1585 markers were mapped with the average maker interval of 0.51 cM,covering 97.7% of the genome.Both the two linkage maps have 16 linkage groups,corresponding to the haploid chromosome number of the two species.Approximately,54.5% of markers exhibited significant deviation from the expected Mendelian ratio of segregation,lending in sights into the intrinsic incompatibility between the two species.QTLs related to growth and shell coloration were detected,which could explain 13.1%and 74.9% of the phenotypic variance,respectively.This represents important information for further evaluation.These findings are an important addition to the genomic resources for scallop genetic studies,and are especially useful for investigations on genomic incompatibility for hybridization,genome evolution of closely related species,and genetic enhancement programs in aquaculture. 展开更多
关键词 SCALLOP Genetic map 2b-RAD genotyping Quantitative trait locus mapping Interspecific hybridization
Functional Analysis of Dunaliella salina Calmodulin Kinase Gene 认领
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作者 Zhenyu XING Mingfang WANG +3 位作者 Xiangnan GAO Weiwei XU Yuting CONG Xiaojie CHAI 《农业生物技术:英文版》 CAS 2020年第2期10-13,20共5页
[Objectives] This study was conducted to investigate the function of Dunaliella salina calmodulin kinase(CaM K) gene.[Methods] The sense and antisense gene fragments(223 bp) and spacer sequence(129 bp) of D.salina cal... [Objectives] This study was conducted to investigate the function of Dunaliella salina calmodulin kinase(CaM K) gene.[Methods] The sense and antisense gene fragments(223 bp) and spacer sequence(129 bp) of D.salina calmodulin kinase gene were cloned and inserted into the downstream part of the35 S promoter of the eukaryotic expression vector pM DCMGN-Cat.The siRNA expression system of CaM K gene was successfully constructed.The p CaM K-RNAi expression vector was transformed into D.salina cells by the LiA c/PEG-mediated method,giving transgenic D.salina.The expression of CaM K gene was then analyzed by real-time fluorescence quantitative PCR.[Results]The expression of CaM K gene in the transgenic D.salina was significantly reduced,by 70% compared with the control group,suggesting that the expression of CaM K gene was significantly inhibited.The examination of the growth status of D.salina showed that D.salina cell division and proliferation were also affected.It is proved that CaM K gene has a positive regulation effect on the division and proliferation of D.salina cells.[Conclusions] The study provides important information for further elucidating the function and action mechanism of D.salina calmodulin kinase gene. 展开更多
关键词 DUNALIELLA SALINA CAMK RNAi LiAc/PEG-mediated method Real-time FLUORESCENCE quantitative PCR
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