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71.
Gene expression studies advance our understanding of the effects of stress and glucocorticoids on brain function and give a new direction to animal welfare research. In this context, the presence of messenger RNA s (m RNA s) for corticotrophin releasing hormone (CRH) and vasopressin (VP) in the porcine hypothalamus has recently been documented. This study investigated the expression of CRH, VP and ionotropic glutamate receptor (iGluR) subunit m RNA s in the brains of pigs treated with the synthetic glucocorticoid dexamethasone (Dex; 5 mg kg(-1)i.v.). In the hypothalamus, VP, but not CRH, m RNA was reduced 3 hours after Dex. In the hippocampus, expression of m RNA s for some iGluR subunits appeared to be differentially regulated 6 hours after Dex. In addition, CRH message was detected in the hippocampus and significantly upregulated in the CA1 region 3 hours after Dex. The relevance of these findings to stress neurobiology of the growing pig is discussed. 相似文献
72.
Two naturally occurring antioxidants, ascorbic acid and turmeric, were effective in inhibiting formation of hexanal, (E)-2-penenal, (E)-2-hexenal, (E)-2-heptenal, and (E)-2-octenal when slurries of fermented cucumber tissue were exposed to oxygen. Added ascorbic acid prevented formation of most of these oxidative aldehydes at 175 ppm or greater. Turmeric, which is used commercially as a yellow coloring in cucumber pickle products, was found to almost completely prevent aldehyde formation at 40 ppm. 相似文献
73.
Service RF 《Science (New York, N.Y.)》2000,290(5491):425-427
This year's Nobel Prize in chemistry was awarded to a trio of researchers--Alan Heeger of the University of California, Santa Barbara; Alan MacDiarmid of the University of Pennsylvania in Philadelphia; and Hideki Shirakawa of the University of Tsukuba in Japan--for discovering that plastics can be made electrically conductive. The discovery paved the way for revolutionary applications such as full-color displays for cellular phones and plastic electronics for computerized merchandise. 相似文献
74.
Service RF 《Science (New York, N.Y.)》2000,289(5479):519-521
Many of today's lasers are made from ceramic chips that require expensive clean-room facilities to manufacture, and their color palette is somewhat limited. Researchers have long pinned their hopes on organic materials, which are typically easier and cheaper to process. Now, on page 599, a team reports that they've devised the first electrically powered solid state organic laser, a step that could open the floodgates for novel lasers that are cheaper and that shine in colors inorganics can't match. 相似文献
75.
The effect of pig farming on copper and zinc accumulation in cattle in Galicia (north-western Spain) 总被引:3,自引:0,他引:3
López Alonso M Benedito JL Miranda M Castillo C Hernández J Shore RF 《Veterinary journal (London, England : 1997)》2000,160(3):259-266
Copper and zinc are frequently added at high concentrations to pig diets as growth promoters. Livestock grazing pasture contaminated with pig slurry may, therefore, be at risk from excessive intake of these elements. High liver copper concentrations have been detected in cattle from the agricultural region of Galicia (NW Spain), especially where there is intensive pig farming. The aim of this study was to evaluate whether pig farming does affect accumulation of copper and zinc in cattle in Galicia. Hepatic copper and zinc concentrations in calves were elevated in areas with naturally high levels of these elements in the soil. The densities of young pigs (piglets and growing-finishing pigs), but not reproductive sows, also influenced copper accumulation in calves. Liver copper levels in calves were significantly and positively related to the density of young pigs in the region. In areas with the highest pig densities, more than 20% of the cattle analysed had hepatic copper concentrations that exceeded the potentially toxic concentration of 150 mg/kg fresh weight. There was no evidence that zinc accumulation in calves was affected by pig density. 相似文献
76.
77.
在对鄂豫陕接壤区引种栽培的26个山楂品种进行品比试验和调查分析的基础上,对其中13个引种时间较长,栽培面积较大的品种,采用合理——满意度和多维价值理论的并合规则,进行了综合评价。结果表明,晋京南1号、山东大敞口、大红袍釉山西798202性状表现最佳,可以大力推广;山东大金星和豫北红等次之,可适当发展;北京小金星和朱砂红表现欠佳,应考虑及时淘汰。 相似文献
78.
79.
最近,阿联酋国营公司杜拜港口世界(DPW)以68亿美元的价格接管英国铁行港口(P·O)在美六个主要港口的经营权。然而这笔交易刚一公布,共和党和民主党都有成员跳出来对这笔交易做出批评,指责由阿拉伯公司控制美国港口会导致美国更容易受到恐怖袭击,因此这笔交易可能影响到美国的国 相似文献
80.
Sognnaes RF 《Science (New York, N.Y.)》1941,93(2426):617-618