血清中乐果的高效薄层色谱快速分析方法和气相色谱方法比对研究

目的:通过与传统的GC法作比对,验证血清中乐果的TLC法是否可行。方法:分别采用TLC法和GC法对同一批低、中、高3种浓度的乐果(血清)样品进行测定,并对2法测定结果进行统计分析。结果:秩和检验结果显示,在给定显著性水平α=0 05时,对应各组测定值均为T1 相似文献   

藏药螃蟹甲挥发油化学成分的GC-MS分析研究

目的：研究螃蟹甲根的挥发油化学成分。方法：采用气相色谱-质谱联用仪（GC-MS）对螃蟹甲根的挥发油化学成分进行了分析鉴定。结果：从分离出的30多个中峰中鉴定出21个化学成分。结论：螃蟹甲挥发油的主要化学成分为丁香酚、十六烷酸、9，12-（反，反）十八二烯酸甲酯和愈创醇等成分。     

蛤蚧中污染对二氯苯的气相色谱分析

有关蛤蚧中污染对二氯苯的分析未曾见报道。作者等采用气相色谱法──外标法定量测定蛤蚧中污染的对二氯苯含量。实验结果表明：方法的线性范围为２７μｇ／ｍｌ～１３８μｇ／ｍｌ，相关系数为０．９９９８，平均回收率为９８．９８％，日内、日间ＲＳＤ分别为１．５％、４．６％。本方法简便、灵敏、快速。经过ＧＣ分析表明：污染有对二氯苯的蛤蚧采用冷风摊及日光摊两种方法不同时间的处理后，对二氯苯的含量有不同程度的减少。     

气质联用（GC／MS）法测定血浆中硝苯地平的浓度

本文建立了气相色谱－质谱联用（ＧＣ－ＭＳ）法测定人血浆中硝苯地平浓度的方法。以安定为内标，经气相色谱分离后（程度升温），质谱单离子检测（ＳＩＭ）Ｍ／Ｚ２８４。结果表明：该方法选择性好、灵敏度高，在１￣２００ｎｇ／ｍｌ浓度范围内线性较好，回收率及精密度均能符合要求。     

Comparison of Gas Chromatography and Receptor Bioassay in the Determination of Diazepam in Plasma after Conventional Tablets and Controlled Release Capsules

Abstract: Plasma levels of diazepam and its metabolites were compared after a controlled release formulation and a regular tablet. Both gas chromatographic analysis of plasma diazepam and desmethyldiazepam and radioreceptor assay of total benzodiazepine activity were used. Also the concentrations of benzodiazepine in saliva samples were analyzed by radioreceptor assay. A typical initial plasma peak was seen after the regular tablet but not after the controlled release capsule. Hence the excessive initial sedation can be avoided and the risk of abuse reduced. Desmethyldiazepam increased for about two days after a single dose of diazepam. The receptor assay correlated in general with the sum of diazepam and its desmethyl derivative. The saliva assay gave about 2.5% of the plasma total benzodiazepine which correlates well with the expected free benzodiazepine. It seems that both the plasma radioreceptor assay and the saliva assay can be used to monitor the total benzodiazepine concentration.     

A genomic population genetics analysis of the pathogenic enterocyte effacement island in Escherichia coli: the search for the unit of selection

Comparative genomic analysis is a powerful tool for understanding the history and organization of complete genomes. The mathematical tools of population genetics combined with genomic analysis provide a powerful approach to dissect heterogeneities in genome evolution. This study presents a hierarchical analysis of the enterocyte and effacement island (35 kb), which is found in the enteropathogenic and enterohemorrhagic strains in Escherichia coli and in Citrobacter rodentium. The locus of enterocyte and effacement in E. coli is considered to be a clonal unit inside a clonal organism and is expected to evolve as a single unit. This analysis examines the clonal assumption by determining genetic diversity, GC content, and the substitution rates at the different functional levels of (i) the complete pathogenic island, (ii) the five operons in which the island is organized, and (iii) for each of the individual 41 genes that comprise the locus. We find that there is a conserved region that is composed of genes that belong to the type III secretion system and that may be products of horizontal transfer. A more diverse region is composed of genes for secreted proteins and genes that we infer to be original components of the E. coli genome. This genetic mosaic seems to be differentially affected by selection and mutation. Our results suggest that recombination and selection may be breaking this structure so that different elements are, at best, weakly coupled in their evolution. These observations suggest that the units of selection are not the complete island, but rather, much smaller units that comprise the island.     

不同地区高良姜挥发油和1，8－桉油素含量测定比较

按１９９５年版《中国药典》方法测定不同地区高良姜的挥发油含量,以及用环己酮作内标、程序升温毛细管气相色谱法测定挥发油中１,８－桉油素的含量。结果显示：不同地区高良姜的挥发油含量各有差异,在０．８４％～１．３０％之间,其主要成分１,８－桉油素含量为０．２６８％～０．５０１％,占挥发油的２９．８％～３９．８％。１,８－桉油素在２．７０９～６．５７４μｇ的范围内呈线性关系,γ＝０．９９９９,平均回收率为９９．３％（ｎ＝４,ＲＳＤ＝２．４％）。方法精密度高,重复性好,操作简便。     

Simultaneous Detection of ACP1 and GC Genotypes Using PCR/SSCP

The classical enzyme and protein markers ACP1 and GC have gained new importance because of the biological functions of their gene products. ACP1 encodes a low molecular weight enzyme which is now recognized as a phosphotyrosine phosphatase with a role in the regulation of signal transduction pathways, and GC‐globulin acts both as a transporter of vitamin D and as a plasma actin scavenger and plays a role in macrophage activation. These two polymorphisms were phenotyped for decades on the basis of electrophoretic isozyme or protein patterns; the gene structures are now known. Nucleotide substitutions determining the common alleles are close enough at each locus to be contained in one short PCR product. We have developed a simple, rapid and reliable multiplex method based on PCR and SSCP which allows the simultaneous determination of the common ACP1 and GC genotypes.     

磺化法-气相色谱测定蔬菜中六六六、DDT残留量

目的:建立蔬菜中六六六、DDT残留量磺化-气相色谱的分析方法。方法:净化过程采用硫酸磺化法,分析了不同硫酸用量对8种农药的回收率的影响,同时加入除酸步骤,采用DB-1701毛细管柱分离,uECD检测。结果:添加浓度在0.001~0.01 mg/kg之间时,回收率(n=6)在70%~110%之间,相对标准偏差分别为1%~6%,该方法的检出限α-BHC、γ-BHC、β-BHC、δ-BHC、PP′-DDE、OP′-DDT、PP′-DDD、PP′-DDT均为0.001 mg/kg。结论:该方法步骤简单,净化效果好,具有良好的灵敏度、回收率和重现性。     

柴胡超临界二氧化碳萃取物化学成分气相-质谱联用分析

目的：研究柴胡超临界CO2萃取物的化学成分。方法：应用气／质联用技术对柴胡超临界CO2萃取物进行分析。结果：从萃取物中分离并鉴定出11种化合物，其中主要组分为饱和及不饱和脂肪酸。含量占气化产物总量的96．2％。结论：本研究为柴胡的开发利用提供了实验依据。