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共轭亚油酸(Conjugated linoleic acid,CLA)具有诸多生理活性,天然的CLA主要来源于反刍动物产品。在日粮中添加富含多不饱和脂肪酸(Polyunsaturated fatty acid,PUFA)的饲料是提高反刍动物产品中CLA含量的一个重要方法。本文通过PUFA对反刍动物CLA机体、消化道及组织等不同代谢层次的影响进行了综述,提出了目前通过PU-FA提高反刍动物CLA中存在的问题,期望为生产中深入利用反刍动物的高CLA这一优势、提高其产品品质提供帮助。 相似文献
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Microorganisms and its metabolic types are diverse in Xinjiang because of those extreme/special environments of drought, high or low temperature, saline and alkaline, oligotrophy. This article reviewed the research progress and achievements of various microbial resources (bacteria, fungi and actinomycete) in the special environments from the point of its ecology, development and application. Meanwhile, the development trend, protection and sustainable utilization of the microorganism resources were discussed. 相似文献
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Neil Anderson Julie Weiland Jill Pharis Wendy Gagné Elisabeth Janiga Mary Jo Rosenow 《Scientia Horticulturae》2009
‘Bailer’ (Endless Summer™) is a new, pink- or blue-flowered hydrangea that flowers on new wood continuously throughout the growing season. It is also winter-hardy in northern, temperate climates (USDA Z4). Use of Endless Summer as a florist's potted hydrangea would provide consumers with a dual-use product (flowering potted plant, landscape shrub). The objectives were to determine if Endless Summer could be forced as a florist's hydrangea using two forcing regimes (immediate, standard), two soil pH regimes, and two pinching treatments. ‘Merritt Supreme Pink’ (pink), ‘Blue Danube’ (blue), and Endless Summer (blue, pink) were forced under immediate (no cold treatment, short- and long-day photoperiods) and standard (6 weeks cold, 4 °C to overcome dormancy) conditions. Since commercial liners were not yet available, cuttings of Endless Summer were used in the immediate forcing experiment. Days to visible flower bud, first color, full flower were recorded, as well as height, no. of branches, no. of flowers, and flower size. In the immediate forcing experiment, only Endless Summer produced flowers. Cultivars differed significantly (P < 0.001) for days to visible flower bud, days to first color, days to full flower, and height. The number of flowers and flower size were not significantly different among pink cultivars. In the standard forcing experiment, Endless Summer reached days to visible flower bud, days to first color, and days to full flower significantly earlier than either comparison, although it exhibited weaker stems and less intense flower pigmentation. Pinching (blue pH) had a significant effect on all traits except the days to full flower and flower size, although no pinching treatment was significant for pink pH. Photoperiod was significant only for the days to visible flower bud (pink pH), days to full flower (blue pH), and final height (blue pH). Further research is needed before Endless Summer can be grown as a dual-use florist's potted hydrangea with acceptable quality. 相似文献
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区域旅游资源开发定位研究——以内蒙古赤峰市为例 总被引:7,自引:1,他引:7
区域旅游资源开发是发展区域旅游的基础 ,开发的定位研究有助于为一地旅游业的发展指明方向。本文从区域角度和空间经济一体化思想出发 ,以赤峰市为例 ,通过对旅游资源的定量与定性研究 ,得到旅游资源的综合评价图式 ,结合区际分析归纳出赤峰市旅游资源开发利用的方向和层次。从而为区域旅游开发的定位研究进行了一般理论的探讨及例证分析 相似文献
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