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苜蓿中华根瘤菌代谢组学样品制备方法的研究 被引量:2
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作者 张田 张志丹 +3 位作者 刘蛟 董会娜 付绍平 张大伟 《工业微生物》 CAS 2019年第4期1-7,共7页
代谢组样品制备是代谢组学研究的基础。本文以维生素B12生产菌株苜蓿中华根瘤菌Sinorhizobium meliloti 320为研究对象,通过检测细胞损伤、ATP泄漏、代谢物回收效率以及细胞代谢淬灭效率综合评价细胞淬灭方法,同时对5种提取试剂的提取... 代谢组样品制备是代谢组学研究的基础。本文以维生素B12生产菌株苜蓿中华根瘤菌Sinorhizobium meliloti 320为研究对象,通过检测细胞损伤、ATP泄漏、代谢物回收效率以及细胞代谢淬灭效率综合评价细胞淬灭方法,同时对5种提取试剂的提取效率进行比较优化胞内代谢物的提取方法。最终获得苜蓿中华根瘤菌S.meliloti 320的胞内代谢组学样品制备较佳条件:即-20℃40%甲醇淬灭细胞,过滤收集淬灭细胞,甲醇/乙腈/水(体积比为2∶2∶2,外加0.1%的甲酸)与50%甲醇相结合提取胞内代谢物。实验结果显示-20℃的40%甲醇(通过过滤收集细胞)对细胞膜的损伤较小,且细胞代谢淬灭效率和回收效率较高;甲醇/乙腈/水(体积比为2∶2∶2,外加0.1%的甲酸)与50%的甲醇对胞内代谢物的提取效率较高且有互补作用。 展开更多
关键词 苜蓿中华根瘤菌 代谢样品制备 细胞淬灭 胞内代谢物提取
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偏最小二乘分光光度法用于多组份分析 被引量:3
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作者 倪永年 《岩矿测试》 CAS CSCD 北大核心 1989年第4期258-262,共5页
本文用偏最小二乘法(PLS)进行多组份光度分析。该法用隐变量矩阵代替吸光度及浓度矩阵,数据处理效果优于经典的多元线性回归法。本文还对多组份光度分析中波长的选择作了研究,提出以吸光系数行列式之值作波长选择判据。实验表明,由此法... 本文用偏最小二乘法(PLS)进行多组份光度分析。该法用隐变量矩阵代替吸光度及浓度矩阵,数据处理效果优于经典的多元线性回归法。本文还对多组份光度分析中波长的选择作了研究,提出以吸光系数行列式之值作波长选择判据。实验表明,由此法选择波长是适宜的。将本文提出的方法对Co,Ni,Cu三组份体系进行了分析,获得了较好的结果。 展开更多
关键词 偏最小二乘 光度法 样品
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安太堡11#煤元素地球化学特征及环境效应 被引量:8
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作者 宋党育 王文峰 秦勇 《煤炭转化》 CAS CSCD 北大核心 2003年第1期41-44,共4页
对安太堡露天煤矿太原组 1 1 #煤层样品中 41种元素的进行了测试分析 ,讨论了该煤层中微量元素的富集特征与分布赋存状况以及元素地球化学特征的环境效应 .研究表明 :除 S,U,Se,Br和 Mo明显富集之外 ,其他有害元素的含量较低 ,对环境的... 对安太堡露天煤矿太原组 1 1 #煤层样品中 41种元素的进行了测试分析 ,讨论了该煤层中微量元素的富集特征与分布赋存状况以及元素地球化学特征的环境效应 .研究表明 :除 S,U,Se,Br和 Mo明显富集之外 ,其他有害元素的含量较低 ,对环境的危害性较小 ;U,Se和 Mo以及部分硫赋存在硫化物、碳酸盐及黏土矿物中 ,用物理洗选方法可以脱除 ;有机硫所占比例较高 ,难以脱除 ,对环境的危害潜势相对较大 ,但可以考虑化学脱硫、利用过程中脱硫或分层开采的方式来降低硫分对环境的危害程度 . 展开更多
关键词 元素地球化学特征 环境效应 安太堡露天煤矿 太原11#煤层样品
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姐妹情深 何须言语表达
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作者 殷中祥 《农村百事通》 2007年第8期50-51,共2页
样品组一直是现场坐车位的员工向往的部门.因为样品组很少有赶产量的压力.更注重的是质量,并且很少加班.而工资却与其他组的员工不相上下。但想进样品组却不是那么容易的事,机会往往是可遇不可求。不过,最近样品组刚好有个员工离... 样品组一直是现场坐车位的员工向往的部门.因为样品组很少有赶产量的压力.更注重的是质量,并且很少加班.而工资却与其他组的员工不相上下。但想进样品组却不是那么容易的事,机会往往是可遇不可求。不过,最近样品组刚好有个员工离职了.所以就出现了一个空缺.这给了许多的现场员工一个希望。 展开更多
关键词 样品组 工作岗位 员工情感 岗位竞争
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Construction of AFLP Molecular Marking System in Mangifera indica L. 被引量:2
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作者 王园 金志强 +1 位作者 陈业渊 雷新涛 《Agricultural Science & Technology》 CAS 2009年第5期72-75,共4页
[Objective ] The study aimed to construct the AFLP molecular marking system in Mangifera indica. [ Method ] Four varieties of Mangifera indica were used to explore new ways for high-quality DNA, and AFLP analysis of 3... [Objective ] The study aimed to construct the AFLP molecular marking system in Mangifera indica. [ Method ] Four varieties of Mangifera indica were used to explore new ways for high-quality DNA, and AFLP analysis of 31 varieties of Mangifera indica was carried out to detect the varietal genetic diversity. [ Result] 14 pairs of primers with stronger polymorphism, better banding patterns and higher resolution were screened out from 64 pairs of selective amplification primers. Then they were used to analyse the fingerprint of 31 varieties of Mangifera indica, the results showed that the ratio of polymorphic bands amplificated by the 14 pairs of primers reached 97% in 31 varieties of Mangifera.[ Conclusion] It was suggested that AFLP was suitable for detecting the polymorphism of Mangifera indica resources. 展开更多
关键词 Mangifera indica Germplasm resourse AFLP Genetic diversity
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基于SCX/SAX混合填料的集成化蛋白质组学样品前处理方法 被引量:3
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作者 孙秀杰 唐君 +4 位作者 陈文东 柯弥 胡巢凤 许瑞莲 田瑞军 《中国科学:生命科学》 CSCD 北大核心 2018年第2期188-194,共7页
本文建立了一种基于强阳离子交换填料/强阴离子交换填料(SCX/SAX)混合填料的集成化蛋白质组学样品前处理方法.本工作将前期已发展的离心式集成化蛋白质组学样品前处理技术SISPROT中的SCX填料替换成SCX和SAX混合填料,以溶菌酶和牛血清白... 本文建立了一种基于强阳离子交换填料/强阴离子交换填料(SCX/SAX)混合填料的集成化蛋白质组学样品前处理方法.本工作将前期已发展的离心式集成化蛋白质组学样品前处理技术SISPROT中的SCX填料替换成SCX和SAX混合填料,以溶菌酶和牛血清白蛋白为模型蛋白,研究了3种pH(3,7.4,12)条件下蛋白质在SCX/SAX混合填料上的保留行为;应用BCA方法对SCX/SAX混合填料的比例进行了优化,并应用SDS-PAGE法对酶解步骤中pH变化引起的蛋白质丢失情况进行了系统的考察.实验结果发现,在pH 7.4条件下,质量比为1:1的SCX/SAX混合填料的富集效率最佳,蛋白质富集容量为180μg,是SCX填料富集容量的两倍左右;且酶解步骤的pH变化过程不会影响蛋白质在SCX/SAX混合填料上的保留.最后应用改进的SISPROT方法对少量肠癌组织样品进行了集成化蛋白质组学样品前处理和分析,并与传统的基于SCX填料的SISPROT方法进行了对比研究.结果表明,蛋白质鉴定量、特异性肽段数量和肽段谱图匹配数量均与基于SCX填料的SISPROT技术相当,证实了该方法作为蛋白质反应器的可靠性.鉴于该方法可以实现在生理pH条件下进行样品前处理,且显著提高了上样容量和减少了样品损失,该方法有望成为一种更为通用的集成化蛋白质组学样品前处理技术. 展开更多
关键词 SISPROT SCX SAX 蛋白质富集 蛋白质样品前处理
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Pulse Electromagnetic Effect on Metal Melts 被引量:3
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作者 Krumsky Valeriy V. Shaburova Natalia A. Filimonov Igor E. 《Journal of Chemistry and Chemical Engineering》 2012年第11期967-970,共4页
The aim of the work was the study of the effect of NEMP (nanosecond electromagnetic pulses) on steel properties. Steel treatment was performed under the workshop conditions. The mechanical properties and the microst... The aim of the work was the study of the effect of NEMP (nanosecond electromagnetic pulses) on steel properties. Steel treatment was performed under the workshop conditions. The mechanical properties and the microstructure of the experimental samples and samples prepared by usual way were analyzed. The treatment of metal melt with nanosecond electromagnetic pulses at the crystallization stage makes it possible to change mechanical properties of metal and its structure. 展开更多
关键词 External influence on the melt pulsed electromagnetic treatment structure and properties of metals.
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Agro-biodiversity and Traditional Knowledge on Tunisian Coastal Oases 被引量:1
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作者 M.B. Salah 《Journal of Environmental Science and Engineering》 2011年第3期303-308,共6页
The Tunisian coastal oases constitute a model of very rich plant biodiversity, organized in different floors of cultivation. The date palm is the highest, the second is the diversified fruit trees and the smallest is ... The Tunisian coastal oases constitute a model of very rich plant biodiversity, organized in different floors of cultivation. The date palm is the highest, the second is the diversified fruit trees and the smallest is composed by various other productions. The present paper is the results of a RAA diagnosis and bibliographic analysis of nearly thirty years of work on oases. The aim of this study is to focus on the plant diversity and the traditions in using different products. The survey revealed the existence of nearly 45 local date palm varieties, about 26 fruit trees, 65 vegetables and divers other species. It also raises nearly 30 uses of dates and date palm by-products. This survey shows also that oases inhabitants keep in possessing, for a long time, a knowledge to make ingenious concerning use and conservation of the products and by products of the date palm. This survey has all as much demonstrated the risks from weakening this balance which has long been maintained. Some recommendations to maintain and conserve this system are also presented in this paper. 展开更多
关键词 Agro biodiversity oases traditional knowledge Tunisia conservation.
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Peat swamps at Giral lignite field Western India: understanding the modelling of Barmer basin, Rajasthan, evolution through petrological 被引量:2
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作者 Prakash K. Singh P. K. Rajaka +3 位作者 M. P. Singh V. K. Singh A. S. Naik Alok K. Singh 《International Journal of Coal Science & Technology》 EI 2016年第2期148-164,共17页
The lignite samples collected from Giral lignite field of Barmer basin have been subjected to petrological investigation. The data generated has been discussed to understand the evolution of the paleomires of these li... The lignite samples collected from Giral lignite field of Barmer basin have been subjected to petrological investigation. The data generated has been discussed to understand the evolution of the paleomires of these lignites. The present study reveals that these low rank C coals are chiefly composed of huminite group macerals, mainly telohuminite and detrohuminite, while liptinite and inertinite group macerals occur in subordinate amounts. Not much variation in the maceral composition from Seam-I to Seam-VIII has been observed. Barmer lignites are characterized by a very high GI (〉10) and moderate TPI indicating topogenous mire in the basin which was permanently flooded. The GI and TPI values and the petrography-based facies critical models indicate that these lignites originated mostly under wet forest swamp to clastic marsh having telmatic to limno-telmatic conditions with a moderate rate of subsidence and a very slow fall in ground water table. Further, the GWI and VI values are suggestive of mesotrophic to rheotrophic hydrological conditions having the dominance of herbaceous to marginal aquatic vegetation. There were spells of periodic drowning of peat especially during the formation of Seam-VII. Moderately high concentration of calcium in these lignites along with the presence of framboidal pyrite indicate enhanced sulphate-reducing bacterial activity present in carbonate and sulphate-rich waters in the basin during peat formation. 展开更多
关键词 Peat swamp Petrography - Giral lignite Barmer basin Western India
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Investigation of the Composition and Structure of Ferrous and Manganese-Ferrous Minerals out of Lake-Marsh Ores
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作者 Chuev Anton Andreevich Nikolai Matveevich Fedorchuk Maria Vladimirovna Petrova 《Journal of Chemistry and Chemical Engineering》 2012年第12期1061-1068,共8页
Minerals which enter lake-marsh ores composition are very diverse. There are two large classes of ores: ferrous and manganese-ferrous ores. Each class is divided into groups according to its mineral composition. In t... Minerals which enter lake-marsh ores composition are very diverse. There are two large classes of ores: ferrous and manganese-ferrous ores. Each class is divided into groups according to its mineral composition. In this investigation, ferrous ore sample (Chagodostcha) and manganese-ferrous ore samples (Totyma-2 and Mologa-2) were considered. All samples in the initial state are contaminated with a-quartz and Ab-An feldspars. Thus for purification of the samples, direct flotation method with kerosene agent were used. As a result, almost all impurities were removed from the samples. With the X-ray diffraction method, the authors identified following phases: goethite (ferrous ore) and birnessite (manganese-ferrous ores). Also, the authors used electron probe microanalysis of the original and purified probes and it showed the presence of such impurities as Ca, K, Mg and Ba in birnessite from the manganese-ferrous ores, and AI and Mn impurities in goethite from the ferrous ore. All ore minerals are in a nanocrystalline state (crystallite size is about 10 nm). 展开更多
关键词 Lake-marsh ores debye-Sherer method direct flotation nanocrystals GOETHITE birnessite.
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Quantitative proteomic analysis for high-throughput screening of differential glycoproteins in hepatocellular carcinoma serum 被引量:3
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作者 Hua-Jun Gao Ya-Jing Chen +5 位作者 Duo Zuo Ming-Ming Xiao Ying Li Hua Guo Ning Zhang Rui-Bing Chen 《Cancer Biology & Medicine》 SCIE CAS CSCD 2015年第3期246-254,共9页
Objective: Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths. Novel serum biomarkers are required to increase the sensitivity and specificity of serum screening for early HCC diagnosis. Thi... Objective: Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths. Novel serum biomarkers are required to increase the sensitivity and specificity of serum screening for early HCC diagnosis. This study employed a quantitative proteomic strategy to analyze the differential expression of serum glycoproteins between HCC and normal control serum samples. Methods: Lectin affinity chromatography (LAC) was used to enrich glycoproteins from the serum samples. Quantitative mass spectrometric analysis combined with stable isotope dimethyl labeling and 2D liquid chromatography (LC) separations were performed to examine the differential levels of the detected proteins between HCC and control serum samples. Western blot was used to analyze the differential expression levels of the three serum proteins. Results: A total of 2,280 protein groups were identified in the serum samples from HCC patients by using the 2D LC-MS/MS method. Up to 36 proteins were up-regulated in the HCC serum, whereas 19 proteins were down-regulated. Three differential glycoproteins, namely, fibrinogen gamma chain (FGG), FOS-like antigen 2 (FOSL2), and a-l, 6-mannosylglycoprotein 6-^-N-acetylglucosaminyltransferase B (MGATSB) were validated by Western blot. All these three proteins were up-regulated in the HCC serum samples. Conclusion: A quantitative glycoproteomic method was established and proven useful to determine potential novel biomarkers for HCC. 展开更多
关键词 GLYCOPROTEIN hepatocellular carcinoma (HCC) mass spectrometry PROTEOMICS SERUM
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Construction of Free Amino Acids Composition Data Base for Food
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作者 Hinako Ito Hiroshi Ueno 《Journal of Chemistry and Chemical Engineering》 2014年第5期501-515,共15页
Significant amounts of free amino acids exist in commercially sold vegetables and fruits. Despite of the fact, only a little information is available about the free amino acid contents in foods. To utilize information... Significant amounts of free amino acids exist in commercially sold vegetables and fruits. Despite of the fact, only a little information is available about the free amino acid contents in foods. To utilize information of free amino acids in food, we have carried out the experiments to quantitate the free amino acids by derivatized with NBD-F (4-fluoro-7-nitrobenzofurazan) and analyzed on reversed-phase UHPLC (ultra-high pressure liquid chromatography) equipped with ultraviolet visible detector. Almost all of food extracts contained free amino acids including GABA (T-amino butyrate). Contents of free amino acids vary considerably depending upon vegetables and fruits. Principal free amino acids found in vegetables and fruits were asparagine, glutamine, arginine and GABA, which are involved in important metabolic pathways in human. About 140 species of vegetables and fruits were subjected for the data base. All of the plants and fruits we examined exhibit significant amount of free amino acids, those are clearly distinct from data bases obtained after acid hydrolysis treated food samples. Since glutamate and GABA act as excitatory and inhibitory neurotransmitters in CNS, respectively; free amino acids in vegetables and fruits that we eat daily, should be an important source for the cellular metabolic activities. 展开更多
关键词 Free amino acid GABA data base FOOD UHPLC.
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Refinement of Methodology for Cadmium Determination in Soil Micro-Arthropod Tissues 被引量:3
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作者 ZHU Dong KE Xin +3 位作者 WU Longhua HUANG Yujuan Peter CHRISTIE LUO Yongming 《Pedosphere》 SCIE CAS CSCD 2017年第3期491-501,共11页
Highly precise and reliable determination of heavy metals in soil micro-arthropod tissues remains a challenge because of the small size of the animals and their typical low abundance in metal-contaminated agricultural... Highly precise and reliable determination of heavy metals in soil micro-arthropod tissues remains a challenge because of the small size of the animals and their typical low abundance in metal-contaminated agricultural soils. The present study sought to develop a method for cadmium (Cd) determination in soil micro-arthropods by optimizing the sample digestion procedure, reducing sample weight, modifying sample pre-treatment and validating the methodology with field samples. The optimized digestion conditions comprised a sample mass of 50-150 μg, digestion reagent of nitric acid:hydrogen peroxide (3:1), digestion temperature of 105 ℃, digestion period of 3 h and digestion volume of 30 μL. Defecation of the standard Collembola Folsomia candida (92 h) and the indigenous Collembola Onychiurus yodai (42 h) and ultrasonic cleaning of F. candida increased the accuracy of Cd determination. The recovery of Cd using the refined procedure was 98.9% and the limits of detection and quantification were 0.002 and 0.008 μg L-1, respectively. The within-batch precision values were 〈 3%. The Cd concentrations in the tissues of the Collembola Isotorna sp. collected from a range of metal-contaminated fields determined by the improved method were consistent with the Cd concentrations in the field soils. The results indicate that the optimized method can be used for more accurate or reliable determination of Cd concentrations in soil micro-arthropod tissues. 展开更多
关键词 DIGESTION DEFECATION Folsomia candida micro-samples predatory mite sample pre-treatment ultrasonic cleaning
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A rapid protein sample preparation method based on organic-aqueous microwave irradiation technique
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作者 Shuaibin Wu Hongfei Zhang +4 位作者 Kaiguang Yang Junfeng Ma Zhen Liang Lihua Zhang Yukui Zhang 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第3期526-531,共6页
Fast and efficient sample preparation methods are a prerequisite for protein identification in bottom-up proteomics. Here, an innovative microwave irradiation sample preparation method was developed based on an optimi... Fast and efficient sample preparation methods are a prerequisite for protein identification in bottom-up proteomics. Here, an innovative microwave irradiation sample preparation method was developed based on an optimized organic-aqueous solvent system for protein identification. Specifically, protein solutions containing high-concentration acetonitrile were subjected to 5 min microwave irradiation. After cooling down, trypsin was added and the digestion was performed with 30 s microwave irradiation, and the resulting peptides were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS). A shortened processing time of only 5.5 min is needed with this method(more than 12 h is necessary in the traditional overnight protein sample preparation). Moreover, due to the absence of urea and other chaotropic reagents, the digests can be readily identified by MALDI-TOF MS. When an assessment of this method was performed by digesting a model protein BSA, 69% ± 3% sequence coverage corresponding to 47 ± 3 peptides was obtained, which shows better protein identification than that from the standard overnight protein sample preparation method(51% ± 2% sequence coverage and 23 ± 1 peptides). Another model protein α-casein was used for the analysis of protein phosphorylation with the newly developed method that yielded 4 phosphopeptides with 8 phosphorylation sites, whereas 3 phosphopeptides with 2 phosphorylation sites were obtained from the traditional overnight approach. Moreover, the organic-aqueous microwave irradiation method provides effective digestion for proteins down to fmol. 展开更多
关键词 MALDI-TOF MS microwave organic-aqueous solvent protein identification DIGESTION
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New strategy for virus discovery:viruses identified in human feces in the last decade 被引量:2
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作者 XIE GuangCheng YU JieMei DUAN ZhaoJun 《Science China(Life Sciences)》 SCIE CAS 2013年第8期688-696,共9页
Emerging and re-emerging viruses continue to surface all over the world.Some of these viruses have the potential for rapid and global spread with high morbidity and mortality,such as the SARS coronavirus outbreak.It i... Emerging and re-emerging viruses continue to surface all over the world.Some of these viruses have the potential for rapid and global spread with high morbidity and mortality,such as the SARS coronavirus outbreak.It is extremely urgent and important to identify a novel virus near-instantaneously to develop an active preventive and/or control strategy.As a cultureindependent approach,viral metagenomics has been widely used to investigate highly divergent and completely new viruses in humans,animals,and even environmental samples in the past decade.A new model of Koch's postulates,named the metagenomic Koch's postulates,has provided guidance for the study of the pathogenicity of novel viruses.This review explains the viral metagenomics strategy for virus discovery and describes viruses discovered in human feces in the past 10 years using this approach.This review also addresses issues related to the metagenomic Koch's postulates and the challenges for virus discovery in the future. 展开更多
关键词 next-generation sequencing novel viruses metagenomic Koch's postulates viral metagenomics
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