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31.
Human epigenetic studies suggest that consumption of seaweed prevents mammary cancer, which possibly is explained by iodine daily intake. In this study, we evaluated the efficacy of dietary intake of iodine‐enriched eggs on mammary tumor incidence caused by the expression of activated type ErbB2. Female transgenic mice were divided into three groups, and fed a basic diet, a diet supplemented with ordinary eggs, or with iodine‐enriched eggs. The number of mammary tumors greater than 5 mm in diameter was recorded in mice at 6 months of age. We report that the average number of mammary tumors per mouse was significantly lower in the iodine‐enriched egg‐added diet group than in either the basic diet or ordinary egg diet groups. These results indicate that iodine intake through livestock‐derived products can reduce the incidence of mammary cancers caused by the expression of activated type ErbB2.  相似文献   
32.
OBJECTIVE: To determine the prevalence of iodine deficiency in crossbred cows (taurus x indicus) of Punjab and to assess the diagnostic value of the plasma concentrations of thyroid hormones, total cholesterol and free fatty acids in iodine deficiency. The efficacy of ethiodised oil, as a long-term supplement of iodine, was also evaluated. PROCEDURES: Base-line survey of iodine status was conducted by measuring plasma inorganic iodine (PII) concentration in 48 crossbred cows from 31 dairy units. Concentrations of plasma triiodothyronine (T3), thyroxine (T4), total cholesterol and free fatty acids were compared between iodine deficient and normal cows. Circulating T4 and T3 concentrations were also determined before and after injection of ethiodised oil in cows with low PII levels. RESULTS: The mean prevalence of iodine deficiency was 35.9% and showed considerable geographical variation from 0 to 86% within Punjab. Cardinal clinical signs of iodine deficiency were absent and basal plasma T3 and T4 concentrations and their ratio did not differ between deficient and control cows. Activity of circulating T4 and T4:T3 ratio increased in response to ethiodised oil injection and persisted beyond 70 days after injection. CONCLUSION: Asymptomatic iodine deficiency is prevalent in crossbred cows of Punjab and response to iodine supplementation is the most reliable index of thyroid dysfunction associated with iodine deprivation. The results of this study also support the view that injection of 1 mL of 78% ethiodised oil can prevent iodine deficiency for more than 70 days.  相似文献   
33.
A monoclonal antibody was raised with specificity for the granule bound starch synthase (GBSS1) Wx-B1 homeoallele of wheat (Triticum aestivum L.) using a synthetic peptide immunogen. This was used to develop a simplified enzyme-linked immunosorbent assay (ELISA) for the discrimination of Wx-B1a and Wx-B1b alleles which differ in the starch properties they confer. Discrimination of these alleles is important for the selection of wheat lines for Udon-style noodle production. The simplified ELISA worked in a single antibody (indirect) format and gave improved ease of use, discrimination of alleles and resolution relative to a previously developed 2-antibody (sandwich) ELISA. When the test was validated using breeders seed of a panel of commercial cultivars, heterogeneity of Wx-B1 alleles was observed for a significant proportion of the cultivars tested and this was confirmed using PCR analysis of the Wx-B1 and Wx-A1 genes. This observation has implications for cultivar wheat quality assessment, the application of molecular markers for variety identification purposes and the establishment of mapping populations from commercial cultivars.  相似文献   
34.
玉米不同收获期的子粒品质研究   总被引:17,自引:0,他引:17  
通过3个玉米杂交种、2个播期、4次收获的研究表明:在玉米生理成熟即玉米子粒千粒重最大时,粗脂肪含量最高,质量最佳、尽管粗蛋白相对含量有所降低,但由于子粒产量的增加,使单位面积收获的蛋白产量仍有提高。因此,适时收获不仅可以提高玉米的产量,而且可以改善玉米的品质。  相似文献   
35.
细集料含量对二灰碎石无侧限强度影响的试验   总被引:1,自引:0,他引:1  
以工程实际常用的二灰和集料比例为20:80的石灰、粉煤灰稳定碎石混合料为研究对象,研究分析在不同石灰剂量时,细集料含量对无侧限强度的影响规律。结果表明,当2.36mm以下细集料含量在10%左右时,二灰碎石无侧限强度取得最大值,即二灰材料替代细集料可以得到理想强度的二灰混合料,并可有效提高其抗水侵蚀能力。  相似文献   
36.
选30头经产2~4胎、产期相近、产奶量相近的奶牛随机分成3组,其中2组饲喂高碘日粮。结果表明:在奶牛日粮精料中添加1.0 mg/kg和2.0 mg/kg碘对牛奶的乳脂、乳蛋白、乳糖和SNF无影响;添加2.0 mg/kg碘能显著提高产奶量,而添加1.0 mg/kg碘则无显著影响;添加1.0 mg/kg和2.0 mg/kg碘均极显著提高血碘和乳碘的含量,而且两者存在线性相关(r=0.427,n=30)。  相似文献   
37.
日粮中高碘对母鸡繁殖性能的影响   总被引:3,自引:1,他引:3  
在25周龄母鸡日粮中添加高剂量碘化钾,持续16周,观察产蛋率,种蛋受精率及孵化率的变化,并用RIA法测定鸡血浆中的雌激素、孕酮浓度.结果表明,高碘组母鸡产蛋率下降,种蛋爱精率无明显变化但孵化率降低.母鸡血浆雌激素的基础分泌量无显著变化,但高碘引起孕酮基础分泌量升高,而且导致雌激素、孕酮的周期分泌率紊乱.  相似文献   
38.
Iodine is an essential microelement for human health, and the recommended daily allowance (RDA) of such element should range from 40 to 200 μg day?1. Because of the low iodine contents in vegetables, cereals, and many other foods, iodine deficiency disorder (IDD) is one of the most widespread nutrient-deficiency diseases in the world. Therefore, investigations of I uptake in plants with the aim of fortifying them can help reach the important health and social objective of IDD elimination. This study was conducted to determine the effects of the absorption of iodine from two different chemical forms—potassium iodide (I?) and potassium iodate (IO? 3)—in a wide range of wild and cultivated plant species. Pot plants were irrigated with different concentrations of I? or IO? 3, namely 0.05% and 0.1% (w/v) I? and 0.05%, 0.1%, 0.2%, and 0.5% (w/v) IO? 3. Inhibiting effects on plant growth were observed after adding these amounts of iodine to the irrigation water. Plants were able to tolerate high levels of iodine as IO? 3 better than I? in the root environment. Among cultivated species, barley (Hordeum vulgare L.) showed the lowest biomass reductions due to iodine toxicity and maize (Zea mays L.) together with tobacco (Nicotiana tabacum L.) showed the greatest. After the screening, cultivated tomato and potato were shown to be good targets for a fortification-rate study among the species screened. When fed with 0.05% iodine salts, potato (Solanum tuberosum L.) tubers and tomato (Solanum lycopersicum L.) fruits absorbed iodine up to 272 and 527 μg/100 g fresh weight (FW) from IO? 3 and 1,875 and 3,900 μg/100 g FW from I?. These uptake levels were well more than the RDA of 150 μg day?1 for adults. Moreover, the agronomic efficiency of iodine accumulation of potato tubers and tomato fruits was calculated. Both plant organs showed greater accumulation efficiency for given units of iodine from iodide than from iodate. This accumulation efficiency decreased in both potato tubers and tomato fruits at iodine concentrations greater than 0.05% for iodide and at respectively 0.2% and 0.1% for iodate. On the basis of the uptake curve, it was finally possible to calculate the doses of supply in the irrigation water of iodine as iodate (0.028% for potato and 0.014% for tomato) as well as of iodide (0.004% for potato and 0.002% for tomato) to reach the 150 μg day?1 RDA for adults in 100 g of such vegetables, to efficiently control IDD, although these results still need to be validated.  相似文献   
39.
螺杆是挤压机的重要组成部分。以挤压机螺杆构型参数阻流环直径、轴头间隙长度、螺杆转速、螺纹升角为试验因素,以浸提玉米胚原油的碘值为考察指标,研究挤压参数对碘值的影响。通过四因素五水平二次正交旋转组合法设计试验,利用SAS9.1软件对试验数据进行响应面分析,得到最佳挤压膨化工艺参数为阻流环直径92 mm、轴头间隙长度16 mm、螺纹升角为7°06′、螺杆转速为180 r/min,在最优参数下碘值为78.56 g/100 g。  相似文献   
40.
锌、硒、碘对蛋鸡蛋黄着色效果的影响   总被引:2,自引:0,他引:2  
试验研究了饲粮中添加微量元素锌、硒、碘对蛋鸡蛋黄着色效果的影响。结果表明,日粮中外加锌、硒、碘水平高于正常需要量一倍时,可使蛋黄颜色提高1~2个罗氏比色单位,达到了国际上所规定的出口鲜蛋蛋黄颜色要达到8级或8级以上的要求,并对鸡蛋可食部分其它矿物元素沉积量无明显影响。  相似文献   
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