茶叶中痕量硒的催化极谱法测定

茶叶中痕量硒的催化极谱法测定陈安民，江丽蓉（绵阳农业专科学校中心实验室，绵阳６２１０００）关键词：催化极谱法，痕量硒硒是人体必需的微量元素之一，富硒茶乃是一种很理想的富硒食品。在我国以陕西紫阳县及湖北恩施两地出产的茶叶含硒最高（平均０．７μｇ／ｇ），...     

中药微量元素研究中若干热点课题

评进了当前中药徽量元素研究中的若干热点课题；1．微量元素与中药品种、产地的关系；2．微量元素与中药性味、归经，功效的关系；3．中药微量元素的存在状态；4．中药内有机成分与微量元素的相互关系；5．微量元素对中西药配伍的影响；6．微量元素的毒副作用．共引用文献29篇．     

妊娠中期孕妇头发微量元素观察

为了解妇女妊娠中期营养状况，对１９９６年产科门诊采集的杂结果进行回顾性分析，结果表明，孕中期妇女有５９．６４％存在宏量和微量元素缺乏，其中钙缺乏占首位，铁缺乏占第二位，锌缺乏占第三位，镁变化不大。缺钙严重程度与季节有关。提示孕中期应对孕妇给予膳食结构的调整，适时补充营养和钙，以满足母胎之需要，减少母儿并发症。     

肿瘤患者放疗前后血清八种微量元素含量的研究

对临床、病理、放射线或CT检查确诊的82名癌肿患者，在放疗前后和对42名健康人进行了微量元素铁、锌、铜、锰、硒，铬、钴、镍的分析。研究结果显示：1．癌肿患者血清铜、镍、锰、铬、钴的含量比健康人高，而血清锌、铁、硒的含量却比健康人低；2．血清Cu／Zn、Cr／Zn、Co／Zn、Ni／Zn的比值癌肿患者均比健康人高，而Fe、Zn、Se／Zn的比值却相反。因此，可根据血清铜升高、血清锌降低，血清铜／锌比值升高的特点。用于癌肿的早期诊断；3．癌肿患者放疔后血清铁、锌含量进一步下降，铜、锰、铬的含量也出现降低，唯有硒的含量有所上升。因此，放疗时应注意补充铁、锌、铜元素。     

Trace level analysis of volatile and semi-volatile organic compounds in water using a membrane/jet separator interfaced to an ion trap mass spectrometer

An ion trap mass spectrometer, equipped with a membrane/jet separator interface, is used for the direct detection of volatile and semi-volatile organic compounds in aqueous solutions. Aqueous sample is passed through a capillary membrane, the outside surface of which is continuously purged by helium. The permeate is pneumatically transported to the mass spectrometer via a jet separator which acts as an additional enrichment device. The performance and response characteristics of non-porous silicone and microporous polytetrafluoroethylene (PTFE) membranes are studied. The microporous membrane allows sufficient water to pass for it to be used as a reagent gas for chemical ionization. Both types of membranes provide detection limits in the parts per trillion (pptr) to parts per billion (ppb) range with a linear dynamic range of 3 orders of magnitude for some volatile organic compounds. Results show that there is no detectable matrix effect on response in the selected cases examined. The use of microporous membranes to analyze more polar compounds, such as 5-hydroxymethyl furfuraldehyde and lactic acid, is also demonstrated. The effects of other experimental parameters, such as membrane temperature and length, on sensitivity are also investigated.     

Determination of Azidothymidine – an Antiproliferative and Virostatic Drug by Square‐Wave Voltammetry

The 3′‐azido‐3′‐deoxythymidine (AZT, Zidovudine) is an antiproliferative and virostatic drug widely used in human immunodeficiency virus type 1 (HIV‐1) infection treatment. With respect to side effects of high doses and a short half‐life of AZT, a fast and simple detection method for this agent could be helpful. The aim of our study was to determine AZT levels in natural samples (urine, serum, whole blood, and cell cultures, such as the HaCaT line of keratinocytes) without their mineralization and/or purification, by means of electrochemical methods using hanging mercury drop electrode (HMDE). On this electrode, AZT undergoes irreversible reduction at the peak potential near E_p?1.1 V (vs. Ag/AgCl/3 M KCl). Reduction AZT signals were measured by cyclic voltammetry (CV), differential pulse voltammetry (DPV), square‐wave voltammetry (SWV), and constant current chronopotentiometric stripping analysis (CPSA). In phosphate buffer (pH 8) the SWV yielded the best AZT signal with the detection limit of 1 nM. The determination of AZT concentration in biological materials is affected by electroactive components, such as proteins and DNA. For monitoring the influence of these compounds, AZT reduction was performed in the presence of 10 μg/mL calf thymus ssDNA and/or 100 μg/mL bovine serum albumin. In these cases, the detection limit increased to 0.25 μM. Also studied was the AZT concentration in keratinocyte cells (HaCaT line) during cell cultivation. It has been shown that the SWV may be considered as a useful tool for the determination of AZT concentration in cell cultures, and for monitoring AZT pharmacokinetics.     

766例厌食患儿病因分析

将766例厌食患儿发中元素含量与对照组比较，发Zn、Ca、Cu含量明显低于对照组，而Fe、Pb含量婴幼儿明显高于对照组，提示Zn、Ca等营养元素缺乏引起的体内元素代谢紊乱可能是厌食的病因，同时发现喂养不当和不良饮食习惯也是厌食的重要原因，提示学龄前儿童是厌食的好发年龄。     

庐山儿童发中微量元素与生长发育关系的调查

调查分析了庐山５０８名１－７岁儿童发中锌，铁，铜含量，并对其与儿童生长发育的关系进行了探讨。结果表明，微量元素与生长发育密切相关。     

Determination of trace elements in the Lavender inflorescence (Lavandula angustifolia Mill.) — Lavender oil system

Bulgaria is a famous world producer of essential oils. Quality control of the lavender oils produced is an important analytical task in view of their wide use in perfumery and cosmetics, the food industry and aromatherapy. The present paper studies the relationship between the trace elements content in lavender inflorescence (Lavandula angustifolia Mill.) and in lavender oil derived from this inflorescence. Three model regions were investigated: two of them are situated far from industrial areas — the village of Zelenikovo and the town of Pavel Banya, and one region is located near the Plovdiv Non-Ferrous Metallurgical Plant. The content of the elements Cd, Cr, Cu, Fe, Mn and Pb in plants was determined after acid digestion by flame and electrothermal atomic absorption spectrometry (ETAAS). Lavender oils were analyzed directly by ETAAS. The results undoubtedly show that there is no strong correlation between the trace elements content in inflorescence and in essential oils. It might be assumed that the trace elements present and accumulated in the inflorescence do not pass in lavender oil during the production by steam distillation.     

慢阻肺与微量元素

从慢阻肺疾病的临床观察与动物实验，通过分子生物学、组织形态学以及超微结构的变化进行探讨，观测到治疗前后毛发中微量元素的分布、合成和转化。及其维持机体健康的物质基础作用。