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为了了解吉林省长白县山区所产卫矛科雷公藤属植物黑蔓的药理作用,扩大它的药用部位和应用范围,我们从无机元素与中药药效有密切关系的角度出发,实验测出黑蔓含有Ba、Si、Cu、Fe、Zn、Sn、Co、Mn、Mg、Ca、Se等无机元素,本文重点对其中人体必需的微量元素Cu、Fe、Zn、Se作了定量分析。 相似文献
3.
观察硒和维生素A(VA)对支原体肺炎的治疗效果.方法 采用双盲随机对照2×2析因实验设计,选择100例住院支原体肺炎患儿,分为补硒组26例,补VA组23例,补硒和VA组30例以及病例对照组21例,正常组21例.一次补硒量为1mg亚硒酸钠和/或15万单位VA,对照病例组给予常规治疗.结果 与对照组比,治疗后3个补充组的症状和体征缓解天数均有不同程度缩短(P<0.05),补硒组白细胞硒和谷胱甘肽过氧化物酶水平显著上升(P<0.05),补VA、补硒组血清VA水平上升(P<0.01),细胞免疫功能有所改善.结论 硒和VA有协同作用,补充硒或同时加VA,作为辅助治疗支原体肺炎的方法,安全、有效. 相似文献
4.
本实验将大鼠从上海空运至兰州,很快转至高海拔地区,用光镜及电镜观察了亚硒酸钠对大鼠的影响。结果发现在高原环境下大鼠对硒的耐受力减低,引起了大鼠猝死半加得高原缺氧对心肌的损伤,降低了大鼠高原适应性。本文还对其耐受机理进行了初步讨论。 相似文献
5.
Dietary selenium (Se) status is inversely related to vulnerability to methylmercury (MeHg) toxicity. Mercury exposures that are uniformly neurotoxic and lethal among animals fed low dietary Se are far less serious among those with normal Se intakes and are without observable consequences in those fed Se-enriched diets. Although these effects have been known since 1967, they have only lately become well understood. Recent studies have shown that Se-enriched diets not only prevent MeHg toxicity, but can also rapidly reverse some of its most severe symptoms. It is now understood that MeHg is a highly specific, irreversible inhibitor of Se-dependent enzymes (selenoenzymes). Selenoenzymes are required to prevent and reverse oxidative damage throughout the body, particularly in the brain and neuroendocrine tissues. Inhibition of selenoenzyme activities in these vulnerable tissues appears to be the proximal cause of the pathological effects known to accompany MeHg toxicity. Because Hg's binding affinities for Se are up to a million times higher than for sulfur, its second-best binding partner, MeHg inexorably sequesters Se, directly impairing selenoenzyme activities and their synthesis. This may explain why studies of maternal populations exposed to foods that contain Hg in molar excess of Se, such as shark or pilot whale meats, have found adverse child outcomes, but studies of populations exposed to MeHg by eating Se-rich ocean fish observe improved child IQs instead of harm. However, since the Se contents of freshwater fish are dependent on local soil Se status, fish with high MeHg from regions with poor Se availability may be cause for concern. Further studies of these relationships are needed to assist regulatory agencies in protecting and improving child health. 相似文献
6.
Effect of dietary selenium and vitamin E on the biomechanical properties of rabbit bones 总被引:1,自引:0,他引:1
Summary It is generally agreed that combined deficiency of selenium and vitamin E leads to several abnormalities including Kashin-Beck disease which is an endemic and chronic degenerative osteoarthrosis. The abnormalities can be reversed by the administration of various forms of selenium and vitamin E.The present study was designed to investigate the effects of dietary selenium and vitamin E on bone tissue and on the biomechanical properties of bone. Young rabbits of both sexes were fed with either a selenium- and vitamin E-adequate diet (control group), or a selenium- and vitamin E-deficient diet or a selenium-excess diet. The selenium-deficient diet resulted in a significant decrease in plasma selenium level and the selenium-excess diet resulted in a significant increase in the plasma selenium level with respect to the corresponding control values (p<0.05). The diets did not affect the blood cell counts considerably but erythrocyte glutathione peroxidase activity increased (decreased) relatively when the plasma selenium level increased (decreased) (p<0.05). The light microscopic investigations of the bone tissues of the two experimental groups indicate that the findings of the present work are compatible with osteomalacia. The biomechanical properties of the bones from the three groups were determined experimentally with bending tests. Both the Se-and vitamin E-deficient diet and the Se-excess diet decreased the biomechanical strength of the bones significantly while the bones belonging to the control group always had the largest modulus of elasticity (p<0.05). 相似文献
7.
荧光分析法测定血清中微量硒 总被引:1,自引:0,他引:1
为测定血清中微量硒,较低温度消化后,用2,3-二氨基萘为试剂,以荧光法测定,取得了满意的结果。方法简便快速,结果稳定准确。血清中加入标准硒,8次测定的回收率为96.6%~102.4%,平均值±标准差为99.6±1.8%。 相似文献
8.
Bahram Dalir-Naghadeh Siamak Asri-Rezaei Naser Alidady 《Comparative clinical pathology》2006,15(3):149-153
Odds ratio was used to evaluate relationship between sepsis in cattle less than 1 year old and mastitis in cows and erythrocyte glutathione peroxides (GSH-PX) activity as an indicator of selenium status. Data were from 178 blood samples collected from referred cases to Urmia University, Veterinary Teaching Hospital. Low activity of GSH-PX was significantly associated with higher odds of developing sepsis (P=0.005) in young cattle and mastitis (P=0.044) in adult cows. The odds ratios for the low activity of GSH-PX on incidence of sepsis and mastitis were 4.74 and 3.95, respectively. Selenium deficiency was associated with sepsis in young cattle and mastitis in cows, i.e., cattle with low activity of erythrocyte GSH-PX were at increased risk of sepsis and mastitis. 相似文献
9.
研究了纳米硒和亚硒酸钠对断奶仔猪肝脏谷胱甘肽过氧化物酶和脱碘酶活性的影响。将纳米硒和亚硒酸钠2种硒源分别以0.1、0.2、0.3、0.4、0.5、1.0 mg/kg 6个硒水平添加到基础日粮中,配制成12种试验日粮,基础日粮作对照,饲养“杜长大”断奶仔猪(8.3 kg左右)。结果表明:以亚硒酸钠形式添加的硒浓度为1.0 mg/kg时,仔猪生长性能和GSH-Px活性显著低于0.2~0.4 mg/kg硒添加水平(P<0.05),纳米硒添加浓度为1.0 mg/kg,仔猪生长性能和GSH-Px活性仍然保持在高峰平台;硒源添加浓度为0.10~0.40 mg/kg时,两种硒源对GSH-Px活性的影响无显著差异(P>0.05);在0.50和1.0 mg/kg硒添加水平上,纳米硒组GSH-Px活性显著高于亚硒酸钠组(P<0.05)。基础日粮组肝脏脱碘酶活性显著低于各硒源的添加水平(P<0.05),硒源和硒添加水平对脱碘酶活性没有显著影响(P>0.05)。上述结果提示:纳米硒的Weinberg剂量-效应的最适剂量范围宽于亚硒酸钠。 相似文献
10.