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1.
如何补硒     
《首都医药》2001,8(4):72
硒对人体是一种很有益的必需微量元素,它可以抗癌防癌,防治心血管病,治疗克山病和大骨节病,防衰老,防治关节炎、肝病等,体内如果缺硒就会出现相应病症,那么如何补硒呢?   许多缺硒地区,光靠每天从食物中摄取硒是不足以保证健康的。美国、加拿大、澳大利亚、西欧国家及我国都是明显的地区性严重缺硒的国家。粗略地估算平均一个美国人每天的硒摄入量是70~100毫克,而我国大体上只有30~70微克,而一些硒专家认为,为了维持人的生理活动的正常健康,每天摄入量应为150~200微克在补硒中还要考虑各种对硒有拮抗效应元素的摄入量。例如,有些地区的砷含量相应高,则相应地应该提高硒的摄入量。   补硒的药物有亚硒酸钠,该药在我国克山病地区已得到应用,并收到良好效果。除了口服外,还可把该药掺在食盐中或粮食中作为群众性给药的方式。口服剂量以元素硒计,成人约每天250微克,儿童50~100微克,这样的剂量非常安全。   还有一种大家公认经特殊方法培养的含硒酵母,例如面包酵母或啤酒酵母即是理想的硒药剂,硒酵母主要优点是它比无机硒盐更容易消化吸收,且副作用和可能的毒性较小。   在提高血硒水平方面,硒酵母比亚硒酸钠有明显的优越性,其效率比后者大20倍以上。   目前,我国已开始了合成含硒酵母的工作和用于临床治疗缺硒病人。(孙乃强)  相似文献   

2.
李春生 《医药世界》2004,(10):32-33
硒具有保护心脏维持心血管系统正常结构和功能的作用,缺硒与心血管病发病有关。芬兰是普遍缺硒的地域,心脏病的高死亡率和低硒状态相关联,而美国高硒地区心血管疾病死亡率明显低于低硒地区,对位于高硒地区和低硒地区的17个城市的比较也发现有相同规律。  相似文献   

3.
硒酸酯多糖     
硒酸酯多糖硒酸酯多糖,又名硒化卡拉胶(Kappa-Selenocarraeenan),上海天赐福生物工程有限公司专利商品名“硒宝康”胶囊,是由微量元素硒与天然产物硫酸酯多糖通过化学合成的方法,形成含硒的生物活性多糖。生理作用1.构成谷胱甘肽过氧化物酶...  相似文献   

4.
硒和硒化物的药理及药效学研究   总被引:10,自引:0,他引:10  
硒是人体所必需的微量元素之一,为谷胱甘肽过氧化物酶的重要成分,能消除体内有害自由基,维护正常生理功能。硒及硒化物可防治多种与硒缺乏相关的疾病。本文综述近年来有关硒及硒化物的药理和药效学研究进展。  相似文献   

5.
康强硒在恶性肿瘤治疗中的作用   总被引:3,自引:0,他引:3  
康强硒在恶性肿瘤治疗中的作用太原康强生化制药厂(030013)王锦山西省肿瘤医院刘清俊山西省预防医学会张肖渺硒不仅是人体的必需微量元素,近年来的研究表明,硒还有治疗肿瘤的作用。康强硒是富含硒多糖、硒蛋白、硒氨基酸、富硒卟啉等多种生物活性硒成分的粉剂。...  相似文献   

6.
硒是维持人体正常生理功能必需的元素之一,适量摄入具有抗肿瘤、抗氧化、增强人体免疫等多种功能。很多益生菌能将无机硒转化为有机硒和纳米硒(SeNPs),可降低硒毒性,并促进人体吸收。富硒益生菌兼具硒和益生菌的双重功效,对人体健康有重要作用,在食品、药品开发方面具有广阔的市场前景。该文综述了近年来富硒益生菌发酵及生物活性的基础研究,并对当前重点研究的一些富硒益生菌进行阐述。  相似文献   

7.
硒是人体必需的微量元素之一。硒与癌症的发生密切相关。从1986年开始,江苏启东市在肝癌高危人群中用硒预防原发性肝癌。试验人群每天摄入硒200微克,持续第2年,血硒达正常水平。肝癌高发家族一级亲属的肝癌发生率比未补硒的对照组约少25%,且对试验者肝、肾功能均无不良影响。  相似文献   

8.
微量元素硒的防癌抗癌作用   总被引:17,自引:0,他引:17  
目的与方法:通过近几年国内外文献检索,综述了微量元素硒防癌抗癌作用研究进展。结果与结论:近年来的研究表明,硒对动物和人体肿瘤有预防和治疗作用。特别是胃肠道癌和肝癌等受硒的影响最明显,补硒能使其发病率和死亡率下降,硒的防癌抗癌机制是多方面的,其中,硒能增强机体免疫系统是其防癌抗癌的重要机制之一。  相似文献   

9.
微量元素硒的临床应用与展望   总被引:1,自引:0,他引:1  
微量元素硒的临床应用与展望邱业功郭庆华(新疆维吾尔自治区人民医院乌鲁木齐830001)70年代初,发现硒是生物体内必须的微量元素。硒化合物,显示出一系列生理及药理作用,可用于防治癌症及冠心病等。正常人血浆硒含量为1~3ng/L,尿硒含量为0.24ng...  相似文献   

10.
目的:探索硒在认知功能中的作用,硒化合物作为认知功能损伤防治药物的可能性。方法:查阅硒与认知功能的动物试验和人群研究文献,总结硒在认知功能中的作用。结果与结论:硒对维持中枢神经系统的生物学功能具有重要作用,认知功能下降与硒水平下降有关,硒化合物具有成为认知功能损伤防治药物的潜力。  相似文献   

11.
Selenium reduction in cirrhosis is frequently reported. The known beneficial effect of selenium supplementation on cirrhosis is probably obtained from nutritionally selenium-deficient subjects. Whether selenium supplementation truly improves cirrhosis in general needs additional experimental investigation. Thioacetamide was used to induce cirrhosis in selenium-adequate and -deficient mice. Selenoenzyme activity and selenium content were measured and the influence of selenium supplementation was evaluated. In Se-adequate mice, thioacetamide-mediated rapid onset of hepatic oxidative stress resulted in an increase in thioredoxin reductase activity and a decrease in both glutathione peroxidase activity and selenium content. The inverse activity of selenoenzymes (i.e. TrxR activity goes up and GPx activity goes down) was persistent and mute to selenium supplementation during the progress of cirrhosis; accordingly, cirrhosis was not improved by selenium supplementation in any period. On the other hand, selenium supplementation to selenium-deficient mice always more efficiently increased hepatic glutathione peroxidase activity and selenium content compared with those treated with thioacetamide, indicating that thioacetamide impairs the liver bioavailability of selenium. Although thioacetamide profoundly affects hepatic selenium status in selenium-adequate mice, selenium supplementation does not modify the changes. Selenium supplementation to cirrhotic subjects with a background of nutritional selenium deficiency can improve selenium status but cannot restore hepatic glutathione peroxidase and selenium to normal levels.  相似文献   

12.
北五味子的富硒方法和富硒效应研究   总被引:1,自引:0,他引:1  
目的探讨在北五味子生长过程中应用亚硒酸钠,是否能有效提高北五味子中硒的含量。方法分别采用土壤施硒、叶面喷硒、土施加叶喷的方法进行试验。结果土壤施硒、叶面喷硒均能使北五味子的硒含量比对照显著提高,并且随着处理浓度的增加而增加。硒含量土施最高可达0.2797mg/kg,叶喷最高可达3.8459mg/kg。结论试验初步验证,硒元素在北五味子中培植转化的富集效应是很明显的。  相似文献   

13.
Organ distribution and retention of the trace element selenium were studied in rats after inhalation of selenious acid and elemental selenium aerosols. A simulation model of selenium metabolism was developed from data obtained. Although the rate of absorption of these two compounds into blood was different, once absorbed both chemical forms behaved identically. This indicates that both compounds joined the same selenium metabolic pool. The simulation model was extended to estimate the levels of selenium in people inhaling selenium compounds normally found in urban atmospheres and in individuals exposed to selenium compounds in the workplace. Predictions of the model for uptake and organ retention of selenium from the environment were compared to measured organ burdens in humans. Inhalation of selenium compounds at levels normally present in urban atmospheres does not contribute significantly to human body burdens of selenium. The most probable source of selenium in human tissues is due to ingestion of selenium in food. However, selenium present in the workplace, in concentrations at the timeweighted threshold limit value, may pose an inhalation hazard to at least some of the workers.  相似文献   

14.
Selenium.   总被引:1,自引:0,他引:1  
The 4 natural oxidation states of selenium are elemental selenium (0), selenide (-2), selenite (+4), and selenate (+6). Inorganic selenate and selenite predominate in water whereas organic selenium compounds (selenomethionine, selenocysteine) are the major selenium species in cereal and in vegetables. The principal applications of selenium include the manufacture of ceramics, glass, photoelectric cells, pigments, rectifiers, semiconductors, and steel as well as use in photography, pharmaceutical production, and rubber vulcanizing. High concentrations of selenium in surface and in ground water usually occur in farm areas where irrigation water drains from soils with high selenium content (Kesterson Reservoir, California) or in lakes receiving condenser cooling water from coal-fired electric power plants (Belews Lake, North Carolina). For the general population, the primary pathway of exposure to selenium is food, followed by water and air. Both selenite and selenate possess substantial bioavailability. However, plants preferentially absorb selenates and convert them to organic compounds. Aquatic organisms (e.g., bivalves) can accumulate and magnify selenium in the food chain. Selenium is an essential component of glutathione peroxidase, which is an important enzyme for processes that protect lipids in polyunsaturated membranes from oxidative degradation. Inadequate concentrations of selenium in the Chinese diet account, at least in part, for the illness called Keshan disease. Selenium deficiency occurs in the geographic areas where Balkan nephropathy appears, but there is no direct evidence that selenium deficiency contributes to the development of this chronic, progressive kidney disease. Several lines of scientific inquiry suggest that an increased risk of cancer occurs as a result of low concentrations of selenium in the diet; however, insufficient evidence exists at the present time to recommend the use of selenium supplements for the prevention of cancer. The toxicity of most forms of selenium is low and the toxicity depends on the chemical form of selenium. The acute ingestion of selenious acid is almost invariably fatal, preceded by stupor, hypotension, and respiratory depression. Chronic selenium poisoning has been reported in China where changes in the hair and nails resulted from excessive environmental exposures to selenium. Garlic odor on the breath is an indication of excessive selenium exposure as a result of the expiration of dimethyl selenide. The US National Toxicology Program lists selenium sulfide as an animal carcinogen, but there is no evidence that other selenium compounds are carcinogens.  相似文献   

15.
Selenium poisoning occurs worldwide in nearly all domestic animals. Acute selenium poisoning is associated with feeding high levels or injecting excessive amounts of selenium and is usually fatal. The acute poisoning may cause gastrointestinal disturbance, muscle weakness, depression of the central nervous system, prostration and death (1-2). Chronic selenium poisoning in cattle, sheep and horses may result from the consumption of seleniferous plants over an extended period of time. Chronic selenium results in ataxia, incoordination, partial blindness, paralysis, loss of hair or wool, abnormal hoof growth and possibly abnormal changes in behavior (1). There is little information regarding the clinical signs and pathology of selenium toxicosis in marine mammals. Likewise, there is little information regarding normal tissue levels or toxicologically significant levels of selenium in these species. The results of these investigations in sea lions, based on clinical signs, pathologic findings and tissue levels of selenium, suggest subacute or chronic selenium poisoning was most likely from dietary fish high in selenium.  相似文献   

16.
A study on organ clearance of mercury (203HgCl2) and selenium (75SeO32?) given separately or simultaneously in single doses by intraperitoneal injections to mice has been performed. The simultaneous administrations are handled in molar ratios (Hg/Se) less, than equal to or greater than one. Liver, kidneys, spleen and blood contain most of the mercury and selenium, administered, while heart, lungs, skin, muscle and brain only contain small amounts. Both elements are retained to a higher degree in especially kidneys, liver, spleen and blood when co-administered than when administered alone. In kidneys, clearance rate of selenium is found to be independent of mercury administration, with an effective halflife 11.2–13.5 days in accordance with the whole elimination. The clearance of mercury is, however, strongly dependent on coadministered selenium. At low molar ration (Hg/Se ? 1) of administered doses clearance rate is identical to that of selenium, compared to an effective halflife when administered alone. In liver the effective halflife of selenium when administered alone or coadministered with mercury (Hg/Se ratio < 1) is found identical to that of kidneys: 11.2–12.5 days. At increasing molar ratios retention of selenium increases and clearance rate decreases. A marked decrease in mercury clearance from liver is induced by simultaneously administered selenium. The effective halflife becoming extremely administered selenium. The effective halflife becoming extremely long and under certain conditions even an accumulation is found to take place. Concordant relations are found for liver and spleen.Selenium in blood is only affected to a minor degree by mercury. Clearance rate for mercury is decreased by selenium. At a molar ratio between doses (Hg/Se) ? 1 clearance rate is approximately identical to that of selenium. It is indicated that selenium metabolism is quantitatively rather than qualitatively influenced by mercury as mercury administration provokes a higher retention of a given dose of selenium while clearance rate in kidneys and blood is only influenced by high molar ratios (Hg/Se). Contrary to selenium, mercury metabolism is altered both qualitatively and quantitatively as retention as well as clearance rate are influenced by selenium in all organs and in all molar ratios given in kidneys and blood. It is assumed that at least 2 mechanisms exist in the metabolic pathways of mercury: (1) binding to metallothionein; and (2) binding to selenium containing metabolic compounds. As selenium induced an increase in mercury retention it is questioned whether selenium is beneficial in case of chroniic exposure to inorganic mercury. It also implies the question of bioavailability of selenium in animal food items.  相似文献   

17.
There is an emerging consensus that people consuming large amounts of fish with selenium:mercury ratios below 1 are at higher risk from mercury toxicity. As the relative amount of selenium increases compared to mercury, risk may be lowered, but it is unclear how much excess selenium is required. It would be useful if the selenium:mercury ratio was relatively consistent within a species, but this has not been the case in our studies of wild-caught fish. Since most people in developed countries and urban areas obtain their fish and other seafood commercially, we examined selenium:mercury molar ratios in commercial fish purchased in stores and fish markets in central New Jersey and Chicago. There was substantial interspecific and intraspecific variation in molar ratios. Across species the selenium:mercury molar ratio decreased with increasing mean mercury levels, but selenium variation also contributed to the ratio. Few samples had selenium:mercury molar ratios below 1, but there was a wide range in ratios, complicating the interpretation for use in risk management and communication. Before ratios can be used in risk management, more information is needed on mercury:selenium interactions and mutual bioavailability, and on the relationship between molar ratios and health outcomes. Further, people who are selenium deficient may be more at risk from mercury toxicity than others.  相似文献   

18.
目的建立中药黄芪以及黄芪发酵液中有机硒和无机硒的含量测定方法。方法采用微波消解和三羟甲基氨基甲烷-盐酸(Tris-HCl)缓冲溶液提取后获得总硒和无机硒,并用原子荧光光谱法测定总硒和无机硒的含量,差值即为有机硒的含量。结果硒的质量浓度在0~100μg·L~(-1)范围内与测定值呈线性变化,检出限为0.090 4μg·L~(-1),回收率为94%~104%。结论该方法简单、灵敏、快速,可作为中药及其发酵液或萃取液中硒含量的测定方法。  相似文献   

19.
张劲松 《医药世界》2004,(10):43-44
This review analyzes the research data of selenium in liver diseases conducted by China scientists in recent years. It is found from these researches that suboptimal selenium in serum is a common phenomenon of liver diseases, the severer, the more deficient; supplementation of selenium in nutritional level is beneficial for diseases control and better recovery of drug treatments; selenium may inhibit hepatitis virus by adjusting immunity,increasing antioxidant defense, and suppressing mutation; selenium at nutritional level could prevent liver fibrosis in rats models as well as liver cancer in either animal models or human beings  相似文献   

20.
Selenium is an essential nutrient for human health with a narrow range between essentiality and toxicity. Selenium is incorporated into several proteins that perform important functions in the body. With insufficient selenium intake, the most notable effect is Keshan disease, an endemic cardiomyopathy in children. Conversely, excessive selenium intake can result in selenosis, manifested as brittle nails and hair and gastro-intestinal disorders. As such, guidance values have been established to protect against both insufficient and excessive selenium exposures. Dietary Reference Intakes (DRIs) have been established as standard reference values for nutritional adequacy in North America. To protect against selenosis resulting from exposure to excessive amounts of selenium, several government and non-governmental agencies have established a range of guidance values. Exposure to selenium is primarily through the diet, but monitoring selenium intake is difficult. Biomonitoring is a useful means of assessing and monitoring selenium status for both insufficient and excessive exposures. However, to be able to interpret selenium biomonitoring data, levels associated with both DRIs and toxicity guidance values are required. Biomonitoring Equivalents (BEs) were developed for selenium in whole blood, plasma and urine. The BEs associated with assuring adequate selenium intake (Estimated Average Requirements – EAR) are 100, 80 and 10 μg/L in whole blood, plasma and urine, respectively. The BEs associated with protection against selenosis range from 400 to 480 μg/L in whole blood, 180–230 μg/L in plasma, and 90–110 μg/L in urine. These BE values can be used by both regulatory agencies and public health officials to interpret selenium biomonitoring data in a health risk context.  相似文献   

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