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11.
目的建立高效液相色谱-质谱法测定人尿液中乙基葡萄糖醛酸苷。方法取空白人尿液加入EtG-D5内标工作液和冷甲醇(4℃),经涡旋、离心,取上清液于水浴氮气吹干,以沉淀杂质,采用Agilent Zorbax Bonus-RP色谱柱分离,以乙腈∶0.1%甲酸水溶液(5∶95)为流动相,采用负离子模式质谱检测,在选择离子监测模式下进行定性和定量测定。结果尿液中EtG在50~5 000ng/mL范围内线性关系良好,检出限为18ng/mL,方法回收率为90.2%~101.7%,相对标准偏差小于10%。结论所建方法简便,具有较高的回收率和精密度,适用于尿液中EtG的检测。 相似文献
12.
液相色谱-质谱联用技术在毒物分析中的应用 总被引:1,自引:0,他引:1
本文简要综述了液-质(LC-MS)联用的基本结构以及该技术近年来在滥用药物、治疗药物和杀虫剂中的应用,为进一步扩大液-质联用技术在毒物分析领域中的应用提供参考. 相似文献
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通过选用THT(C_4H_8S)对LPG液相的加臭试验,确定了较合适的加臭剂量。为保证该工艺的安全可靠、经济实用及操作方便,采用氮气作载体,用经改制的磁性浮子液位计作指示。实施证明该工艺是切实可行的。 相似文献
15.
目的:建立复方丹皮酚凝胶中丹皮酚的含量测定方法.方法:采用高效液相色谱法,色谱柱为SHIMADZU VP-ODS(4.6 mm×150 mm, μm),流动相为甲醇-水(50∶50),检测波长为274 nm.结果:丹皮酚进样量为0.05~0.30 μg时呈良好的线性关系(r =0.999 8).平均回收率为100%,SD为0.87%(n =5).结论:PLC法可用于复方丹皮酚凝胶的质量控制. 相似文献
16.
商业银行资产负债期限结构错配的流动性风险和利率风险分析 总被引:1,自引:0,他引:1
本文结合目前我国商业银行普遍存在的资产负债期限结构错配的现状,分析了产生流动性风险和利率风险的可能性,并认为利率风险是因流动性风险而派生出的风险。在此基础上,提出了商业银行流动性管理的三种方法:期限匹配法、资产组合法和综合法。 相似文献
17.
《Science & justice》2021,61(5):579-585
One of the main tasks in forensic entomology is the determination of the minimum post-mortem interval (PMImin) based on the age of the juvenile insects feeding and developing on the dead body. An important task is to store the evidence appropriately so that the evaluation and expert report can be used in court. However, existing recommendations can be contradictory or lacking scientific validation, e.g. by proposing various preservation liquids without knowing whether and to what extent the period of storage in such a liquid has an effect on the length of the preserved larvae. Storage time can be an issue since, due to technical and procedural circumstances, killed larvae may be stored for hours, days, weeks or even longer prior length measurement. A changed body length would have consequences for the entomological report, as the age of the larvae is usually derived from their length.This study investigates the effect of four differently concentrated ethanol solutions (70%, 80%, 90% and 96%) during a storage period of up to 196 days on the body length of stored larvae of the forensically important blow fly species L. sericata (Diptera: Calliphoridae). Larvae of different ages (24 h, 48 h and 72 h after hatching) were killed by immersion in hot, non-boiling water (≥80 °C) for at least 30 s. Their lengths were measured immediately. Subsequently samples were stored in ethanol of appropriate concentration at room temperature (approx. 22 °C). Further length measurements were made at 16 different storage intervals between 1 and 196 days.Many specimens showed a length decrease for most storage conditions and all larval ages. However, there was a tendency for 48 h- and 72 h-old larvae to increase in length after the first days of storage of up to 1.1 mm which may lead to an erroneous overestimation of the PMImin using this kind of specimens. All changes in length within each cohort over total time were in the range of +7% to −9.1%. Significant differences in length changes within the first days of storage were found mainly in larvae stored in 70%- and 80%-ethanol, but larvae stored in 90%- and 96%-ethanol showed first significant differences on day 56 at the earliest.Our results lead to the recommendation that the measurements of fly larvae samples should be taken immediately after killing and before storage to avoid any effects. Ethanol ≥90% should be used for storage. 相似文献
18.
Methoxetamine (MXE) is a new synthetic drug of abuse structurally related to ketamine and phencyclidine. A case of a 29-year-old male with acute toxicity related to the analytically confirmed use of MXE is reported. The man was found dead at his residence. Biological material was analyzed using liquid chromatography–tandem mass spectrometry. The concentration of MXE in urine of the deceased was 85 μg/mL. Despite the vial containing the blood sample being destroyed during transportation and the blood leaking out into the cardboard packaging, the blood level of MXE was estimated. After determination of the cardboard grammage (approx. 400 g/m3) and the mean mass of the blood obtained after drying (0.1785 ± 0.0173 g per 1 mL), the estimated blood concentration of MXE was found to be 5.8 μg/mL. The high concentration of MXE in blood and urine and the circumstances of the case indicate an unintentional, fatal intoxication with this substance. 相似文献
19.
作者建立了同时测定人血清中氯丙嗪与氯扎平浓度的反相高效液相色谱(RP—HPLC)法。以利眠宁为内标,用环己烷—乙醚(1:1)混合溶剂提取血清中氯丙嗪和氯扎平。高浓度中毒者血清(>1ug/ml)则用乙腈沉淀后直接进行色谱测定。血清中氯丙嗪、氯扎平的方法回收率乎均各为98.5±4.0(SD)%,CV4.2%;99.9±4.1(SD)%,CV4.1%。两药在血清中的最低检测浓度为10ng/ml。本法应用于临床氯丙嗪、氯扎平合用药物的血浓度监测及司法中毒案例的分析,结果满意。 相似文献
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