土壤中硒流动注射氢化物发生原子吸收法检测

硒是人体生长发育过程中所必需的微量元素之一.土壤中的水溶性硒易被植物吸收[1],而植物中硒含量又与人和动物的健康有直接关系.所以测定土壤中水溶性硒含量具有重要意义.     

硒的特性、毒性及在某些国家的现状

硒是动物和人的一种必需微量元素,并在抗氧化物酶—谷胱甘肽过氧化物酶中发挥重要作用。这种酶能保护细胞膜免受脂质过氧化物的损伤。研究表明,硒缺乏能引起人和动物的健康损害;硒的毒性也非常大,能引起人和动物中毒。硒主要来源于膳食,在世界上的许多地区土壤中的硒水平通常反应了人群中的硒水平。食物中硒的活性和毒性取决于硒的化学结构。通常情况下,有机硒较无机硒(硒酸盐、亚硒酸盐)活性大而毒性小。     

揭开人体健康的奥秘一个主宰生命的微量元素硒

近20年来,大量实际研究证实了硒是动物和人体生命不可缺少的必需元素。硒与人体疾病的研究表明,如硒与癌症,硒与心血管病,硒与肝病、糖尿病、关节病、视力减退、生殖障碍,硒具有抵抗这些疾病发生的功能。美国科学家最新研究证明,每人每天服约200微克硒后,可使肺癌、结肠癌及前列腺癌下降 50％。 1973年,联合国卫生组织宣布:“硒是人和动物生命中不可缺少的微量元素。” 哪些人特别需要补硒     

关注硒与人体健康

饮食中的硒往往无法达到人体最佳摄入量 硒是维持人体健康所必需的矿物质元素。作为一种强抗氧化剂，它可以抵抗自由基、提高免疫力、保护人体、抵御外来有害物质。但是，人自身不能合成硒，人体新陈代谢所需的硒主要来源于食物中。动物脏器、禽蛋以及虾、蟹等海产品的硒含量相对较高，但动物脏器、禽蛋不宜多吃，虾、蟹等海产品的硒在人体内利用率低；粮食、蔬菜和水果的硒含量低，对人体所需硒摄入量贡献不大。     

玉米植株叶面喷硒的效果研究

<正> 硒是人和动物必不可少的一种微量元素.近年来人们对采用什么样的方法、手段,以提高饲草饲粮的硒含量做了大量的工作。Gissel—Nielsen 对丹麦二十个低硒牧区进行饲料加硒、土壤施硒肥、植株叶面喷硒试验,结果以叶面喷硒效果好。新西兰报导在牧草上喷硒,三个月内牲畜能食入75—80%的硒,并可预防白肌病。有人试验表明,幼龄谷物叶面喷硒5g/ha 是有效的,未发现在生态系统中有硒的积累。     

加快开发我省紫阳县富硒资源

硒是人和动物生命必需的微量元素，人体日需量为40～240微克，世界卫生组织建议日补硒为200微克。然而，由于硒的地球化学分布不匀，缺硒遍及世界五大洲许多国家，在中国72％的县市谷物含硒在0．05毫克／公斤以下，属低硒地带，中国的膳食调查也证明多数国人日摄入硒仅30～40微克，与200微克的补充量相差几倍。而以陕西紫阳为中心的富硒地带，其土壤、     

血硒,发硒含量与肺癌关系的调查研究

硒在人体生长发育过程中，起着极其重要作用，硒是人体必须的微量元素，硒是人体内某些酶类如谷胱甘肽过氧化物酶的重要组成部分。已知人体及动物四十余种疾患都与硒缺乏有关。因此，当人体长期处在负硒营养状态时，将会对机体不同部位产生不同程度损害，导致疾病发生〔１...     

微量元素硒对健康的影响

硒(selenium)是人体必需的微量元素,硒具有许多重要的生理功能。硒缺乏时,人可患克山病,免疫力降低;过量硒又能引起硒中毒,使人脱发、脱甲、偏瘫等。笔者将近年来国内外有关研究进展综述如下。1 硒是维持生命活力的物质 微量元素硒是世界卫生组织于1973年宣布人体和动物生命中必需的微量元素。随着生命科学的发展,人们已逐步认识到硒具有许多重要的生理功能,硒为维持生育、眼睛、心脏及免疫系统的正常功能所需要,它还起着预防某些重金属中毒,尤其     

中国人为什么需要补硒？

饮食中的硒往往无法达到人体最佳摄入量硒是维持人体健康的必需矿物质元素,硒摄入不足容易引起多种疾病。硒可以抵抗自由基、提高免疫力,保护人体抵御外来有害物质。但是,人体自身不能合成硒,人体"新陈代谢"所需的硒主要来源于食物中的动物脏器及禽蛋,     

硒的生物学作用及其意义

硒是人和动物必需的微量元素之一 ,近年来大量资料证明 ,许多疾病与缺硒有关。就近年来人们关注的硒与疾病的关系 ,对硒的生物学特性、生物学功能及硒与机体免疫功能、人体硒缺乏及需要量部分文献资料作一回顾 ,同时对硒的开发应用国内现状和前景谈一点看法 ,仅供参考     

Selenomethionine: a review of its nutritional significance, metabolism and toxicity

Although the need for selenium in human and animal nutrition is well recognized, the question concerning the proper form of selenium for supplemental use is still being debated. Ideally, selenium should be supplemented in the form in which it occurs naturally in foods. Because the L-isomer of selenomethionine (Se-met) is a major natural food-form of selenium, synthetic L-Se-met or enriched food sources thereof such as selenium yeast are appropriate supplemental forms of Se for humans; for animals, DL-Se-met is acceptable. Ingested Se-met is either metabolized directly to reactive forms of selenium or stored in place of methionine in body proteins. Se-met metabolism is closely linked to protein turnover. At constant intakes in the nutritional range, tissue Se levels increase until a steady state is established, preventing the build-up to toxic levels.     

硒缺乏动物模型的建立及应用

硒是人类和动物维持生命所必需的基本营养元素之一，它在机体内发挥着众多的生物学作用。但是全球缺硒现象非常普遍，硒缺乏成为全球性的普遍问题。为了研究硒缺乏究竟会对人体有何影响，建立缺硒动物模型成为必不可少的关键环节。本文对半个世纪以来国内外低硒动物模型建立的方法以及利用低硒动物模型对硒功能的研究进展作一综述。     

Selenium deficiency and infertility. Andrologic aspects

Absolute selenium deficiency in human is very rare, although suboptimal daily selenium intake may lead to an unrecognized relative deficiency. Among the many consequences ascribed to decreased selenium level, the effect on male fertility is summarised by the authors. Implications from biochemical, animal experimental and human researches are discussed.     

Prediction of whole blood selenium levels in patients on long-term parenteral nutrition

In an attempt to define clinical variables which might predict the whole blood selenium level prior to supplementation, whole blood selenium levels were determined in 21 home parenteral nutrition patients who were not receiving selenium supplementation. These levels were examined for possible correlations by single and multivariant analysis with the following clinical parameters: age at initiation of home parenteral nutrition, months of home parenteral nutrition received, hematocrit, albumin, estimated length of remaining small bowel, kilocalories per kilogram actual body weight infused per day, grams protein per kilogram actual body weight infused per day, and multiple of ideal body weight. Of all the combinations of variables examined, the best correlation obtained was between whole blood selenium levels and the total kilocalories per kilogram body weight per day delivered intravenously (r = -0.89, p less than 0.001). A statistically significant correlation (r = -0.67, p less than 0.01) was also observed between selenium levels and the grams protein per kilogram actual body weight infused per day. However, inclusion of this or additional variables did not increase the predictive value of the equation describing whole blood selenium levels as a function of the calories delivered. The implication of this study is that patients requiring more intensive nutritional support develop lower selenium levels during the course of treatment. Despite these correlations, no single clinical parameter or combination of parameters, however, was of sufficient predictive value to preclude laboratory determination of whole blood selenium values in deciding which patients might benefit from selenium supplementation.     

人血液和尿液中硒元素的形态分析研究进展

硒是人体必需的微量元素,其不同形态决定它在体内的生物有效利用率、毒性和防癌抗氧化作用,因此人血液和尿液中硒元素的形态分析研究具有重要意义。本文综述了近年来人血液和尿液中硒元素形态分析研究进展,详细介绍了样品的前处理技术、色谱分离技术和ICP-MS的检测技术,并对发展前景进行了展望。     

Selenium in Human Lactation

The primary factor determining selenium concentration in human milk is the maternal selenium intake. A significant correlation between selenium in human milk and maternal selenium intake has been reviewed in papers from different regions of the world. Infants fed human milk have higher selenium intake than those fed commercially available formula milk or baby foods. Selenium compounds found in breast milk seem to be more biologically available for infant nutrition than those in formulas. Increased requirements of selenium have been observed in pregnant and lactating women. Supplementation of lactating and pregnant women with different selenium compounds has been assayed, and selenium supplementation of soil and cows has been used to increase the selenium status of children fed infant formula made from cow's milk.     

Report on the 1986 A.S.P.E.N. Research Workshop on selenium in clinical nutrition

Selenium in human nutrition was the theme of the 1986 Research Workshop of the American Society for Parenteral and Enteral Nutrition. At the workshop, evidence for the nutritional essentiality of selenium to humans was reviewed, and it was concluded that Keshan disease, the cardiomyopathy of children and young women described in China, is now firmly linked to selenium deficiency, although other factors may be involved. Selenium metabolism and techniques for assessing selenium status also received attention at the workshop. A measurement of blood selenium levels was accepted, in general, as a valid technique for assessing selenium status in individuals with relatively constant selenium intakes. Clinical practitioners at the workshop reported that some of their total parenteral nutrition patients not receiving selenium presented biochemical evidence of selenium deficiency, but no characteristic clinical syndrome due to selenium deficiency has yet been observed in such patients. The workshop attendees acknowledged the need for an official guideline for selenium use in total parenteral nutrition, but were unable to develop a consensus regarding such a guideline. However, the workshop agreed that any guideline established in the future should specify the type of patients to be supplemented, the dose of selenium to be administered, and the selenium compound to be used. Until that time, the physician supervising the therapy must assume responsibility both for determining the need for selenium supplementation, and for the administration of the supplemental selenium.     

机体免疫机能与微量元素硒关系的研究进展

硒是人体和动物必需的微量元素,近年来,微量元素硒与免疫功能的关系越来越受到人们的重视,硒能增强机体的免疫功能和对传染性疾病的抵抗能力.就硒对机体免疫功能的影响进行了阐述,并强调了科学补硒的重要性.     

Cadmium distribution within corn plants as a function of cadmium loading of the soil

Corn is a widespread crop in some industrialized areas of Northern Italy and Europe where it serves for both animal and human nutrition. In the present paper we examined the distribution of Cd within corn plants grown under both hydroponic and field conditions. The results obtained show that Cd accumulation by different plant tissues may reach saturation without signs of phytotoxicity. Thus cadmium pollution can go undetected even when corn plants are grown in the presence of a consistent amount of Cd. Its accumulation within plant tissues is responsible for the entry of the metal into the food chain. Implications for human and animal nutrition are discussed.     

Reversal of a skeletal myopathy with selenium supplementation in a patient on home parenteral nutrition

There is evidence that selenium deficiency is associated with a fatal specific heart muscle disorder and with a reversible skeletal myopathy. This paper describes a man who became selenium deficient after several years of intractable malabsorption and 15 months of parenteral nutrition at home. Clinically, he developed muscular weakness and tenderness without evidence of heart disease; deficiencies other than selenium were excluded. The patient's muscle strength was measured at weekly intervals by hand-grip dynamometry and by a technique involving voluntary and electrically-stimulated abduction of the right index finger. With selenium repletion, the patient's strength improved with a two-fold increase in force during an involuntary muscle contraction. The patient's complaint of muscle pain resolved. This study provides further information concerning the essential role of selenium in human nutrition.