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硒是一种重要的工业原料[1-2],同时也是生物体中多种酶和蛋白质的重要组成成分,具有很强的生物活性,参与多种生理、生化作用,人体缺硒会造成重要器官的功能失调,导致许多严重疾病的发生[3-4]。硒在自然界中稀少、分散,很少有集中的矿床,地壳中的含量为一亿分之一。由于硒具有半导体、光敏感等特性,所以可用来制造光敏元件、光学仪器及电器元件等。随着科学技术的进步,硒的应用领域不断扩大,主要集中在石油、化工、冶金、电 相似文献
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硒是第4周期第ⅥA族元素,除了具有非金属性外,还有部分金属性。其在地壳中的含量为0.05~0.09 mg/kg,自然界中存在广泛但分布不均。硒是人体和动物必需的微量元素,具有重要的生理生化功能,过量的硒及其化合物有较强毒性,而且硒的适宜剂量范围很窄。本文简单介绍了自然界中硒的存在、硒的生物学效应及其分子基础,以纪念元素周期律发现150周年。 相似文献
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原子荧光法快速测定海藻低聚糖中的硒 总被引:3,自引:0,他引:3
硒是人体必需的微量元素 ,在人的肌体内参与许多重要的代谢过程 ,缺硒会导致某些疾病。近年来 ,补硒品的研制倍受关注。但人体摄入过量硒会引起中毒。因此 ,建立硒的快速、准确的测定方法具有重要意义。硒的传统测定方法是荧光光度法[1 ] 。该法操作烦琐 ,所用试剂毒性大。近年来 ,原子荧光法测定人发、植物及血清中的硒已有报道[2 ,3] ,本文研究了原子荧光法快速测定海藻低聚糖中硒的适宜条件 ,样品用混合酸消解后 ,盐酸还原 ,直接测定 ,回收率为 98 5 %~ 1 0 2 9%。1 实验部分1 1 仪器与试剂XGY 1 0 1 1A型原子荧光分析仪 (地矿… 相似文献
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颜卿 《广东微量元素科学》2008,15(9):70-70
人体必需微量元素的不足或缺乏,主要是缺乏时即会引起机体生物功能及生化代谢的紊乱或异常,尤其是小儿。小儿由于生长发育快,对各种必需微量元素需求量相对增加,因而特别容易引起必需微量元素和宏量元素的不足或缺乏。 相似文献
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微量元素与病毒性肝炎 总被引:5,自引:2,他引:5
微量元素参与机体各种酶及活性物质的代谢,从多方面影响着人的生命过程。肝脏是人体的重要代谢脏器,对微量元素的代谢关系更为密切。病毒性肝炎患者血清硒,锌均明显降低,铜元素高于正常。因此测定患者机体内的微量元素含量,为诊断及治疗提供新的途径和措施,可及时纠正患者体内微量元素的盈缺,有助于改善肝细胞功能及增强机体免疫力。 相似文献
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Selenium exists in several oxidation states and a variety of inorganic and organic compounds, and the chemistry of selenium is complex in both the environment and living systems. Selenium is an essential element at trace levels and toxic at greater levels. Interest in speciation analysis for selenium has grown rapidly in this last decade, especially in the use of chromatographic separation coupled with inductively coupled plasma-mass spectrometry (ICP-MS). Complete characterization of selenium compounds is necessary to understand selenium's significance in metabolic processes, clinical chemistry, biology, toxicology, nutrition and the environment. This review describes some of the essential background of selenium, and more importantly, some of the currently used separation methodologies, both chromatographic and electrophoretic, with emphasis on applications of selenium speciation analysis using ICP-MS detection. 相似文献
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杨容甫 《广东微量元素科学》1995,2(11):7-14
概述了近20年来,硒与肿瘤关系的研究进展.包括:环境中的硒水平与肿瘤,肿瘤患者硒水平及其临床意义,硒的抗癌机理和在防治肿瘤上的应用。 相似文献
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《中国化学快报》2021,32(8):2385-2389
Lipid droplets(LDs) are intracellular lipid-metabolism organelles that involved in many physiological processes,metabolic disorders as well as diseases such as atherosclerosis.However,the specific probes that can visually locate abnormal LDs-rich tissues and track LDs-associated behavior to the naked eye with adequate biosafety still are rare.Herein,we develop a new design strategy of LDs-targeted probe based on the solvatochromism of coumarin derivatives.The results revealed that the emission wavelength of coumarin fluorophores gradually red shift in different solvents with increasing polarity,while absorption wavelength almost unchanged.As a result,the enlarged stokes shift of coumarin was emerged from oil to water.Furthermore,properly reducing water solubility and adding electronic donor at the structure of coumarins can enlarge this type of solvatochromism.This discovery was utilized to develop suitable probe for the image of LDs and LDs-rich tissues with high resolution and biosafety.Therefore,LDs-associated behavior was visible to the naked eye during the process of lipophagy and atherosclerosis.We deem that the developed probe here offers a new possibility to accurately diagnosis and analyse LDs-related diseases in clinic and preclinical study. 相似文献
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土壤环境中的硒对人和动物健康的影响 总被引:14,自引:0,他引:14
廖金凤 《广东微量元素科学》2002,9(3):20-23
硒是人和动物必需的微量元素之一。土壤中的硒含量过多或过低,人和 动物都会出现地方性疾病。土壤中硒的含量与土壤母质、地形、气候条件和土壤条件性质等有关,调节土壤性质可以改善作物的含硒量。防治硒缺额症和硒中毒症,每天必需摄入适量的硒,以100-200μg为宜,但人体对硒的需要量也与食物成分有关。 相似文献
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Phase I and phase II ocular metabolic activities and the role of metabolism in ophthalmic prodrug and codrug design and delivery 总被引:1,自引:0,他引:1
While the mammalian eye is seldom considered an organ of drug metabolism, the capacity for biotransformation is present. Compared to the liver, the metabolic capabilities of the eye are minuscule; however, phase I and phase II metabolic activities have been detected in various ocular structures. The careful consideration of ocular tissue metabolic processes within the eye has important implications for controlling the detoxification of therapeutic agents and for providing the potential for site-specific bio-activation of certain drug molecules, thus enabling significant improvements in drug efficacy and the minimization of side-effect from either local or systemic drug delivery to the eye. Knowledge of these processes is important to prodrug and codrug development and to researchers involved in the design, delivery and metabolism of ophthalmic drugs. This present article reviews the progress in ocular prodrug and codrug design and delivery in light of ocular metabolic activities. 相似文献
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Selenium(IV), in the concentration range 2–100 μg l?1 in contaminated waters, is determined by using the sensitive adsorption-controlled peak obtained by differential pulse polarography in dilute acid solution. Interfering heavy metals are removed on Chelex-100 resin. Selenium(VI) is not electroactive but can be determined after photolytic reduction in the absence of oxygen. Anion-exchange preconcentration is necessary if the total selenium is below the detection limit of 2 μg l?1. 相似文献
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