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31.
32.
口饲胰岛素样生长因子的生理功能 总被引:1,自引:0,他引:1
本文综述了口饲胰岛素样生长因子的动物性实验结果。口饲胰岛素样生长因子具有降低血糖水平、增强机体免疫力、调节动物肠道菌群,促进胃肠道生长发育或肠道组织创伤的愈合等独特的生理功能。 相似文献
33.
当归多糖的生物学功能研究进展 总被引:7,自引:0,他引:7
本文针对当归多糖对免疫器官、细胞免疫和体液免疫、调控细胞因子及造血系统的影响和抗肿瘤等生物学功能作一综述。 相似文献
34.
35.
铬对肉仔鸡生长性能、免疫功能和胴体品质的影响 总被引:5,自引:2,他引:5
用21日龄Arbor Acress(AA)肉公鸡336只,研究饲粮中添加铬对肉仔鸡生长性能、免疫功能和胴体品质的影响。将试验鸡只共分为8个处理组,分别添加源于氯化铬的铬2.0、4.0、6.0、8.0、10.0、12.0和14.0mg/kg。结果表明:饲粮中添加2.0mg/kg铬显著提高了肉仔鸡胸腺重(P<0.10),降低了腹脂率(P<0.10),4.0、6.0mg/kg铬显著提高了全净膛率(P< 0.10),各试验组显著提高了T淋巴细胞转化率(P<0.10);饲粮中添加铬对其余指标则无显著影响(P>0.10)。 相似文献
36.
《The Journal of Applied Poultry Research》2006,15(1):136-144
The gastrointestinal tract contains within it a microenvironment of bacteria that influences the host animal in many ways. The microflora can metabolize several nutrients that the host cannot digest and converts these to end products (such as short-chain fatty acids), a process that has a direct impact on digestive physiology. The microbiota directs the assembly of the gut-associated lymphoid tissue, helps educate the immune system, affects the integrity of the intestinal mucosal barrier, modulates proliferation and differentiation of its epithelial lineages, regulates angiogenesis, modifies the activity of the enteric nervous system, and plays a key role in extracting and processing nutrients consumed in the diet. Despite these important effects, the mechanisms by which the gut microbial community influences host biology remain almost entirely unknown. Recent molecular-based investigations have confirmed the species diversity and metabolic complexity of gut microflora, although there is much work to be done to understand how they relate to each other as well as the host animal. It is almost a century ago that Eli Metchnikoff proposed the revolutionary idea to consume viable bacteria to promote health. Since that time, the area known as probiotics has made dramatic progress, particularly during the past 2 decades. The last 20 yr have also seen the emergence of a new, related area of study—prebiotics. Use of these 2 ideas—providing live nonpathogenic bacteria as well as substrates for their growth—have potential to help optimize the health of animals by manipulating the gastrointestinal tract in positive ways. 相似文献
37.
从农民土地利用偏好以及居民地域性认同出发,将农民土地利用偏好分为农业生产功能偏好和经济生产功能偏好2类;并运用数学方法求取居民地域性认同综合指数,建立Logistic二项回归模型,研究农民土地利用偏好和居民地域性认同的相关性。结果表明,地域性认同程度高的农民更偏好于土地的经济生产功能。地方在开展土地整理或制定土地利用计划时,可根据当地居民地域性认同程度选择增大农地面积或是商铺、工厂的面积,提高人民的满意度。 相似文献
38.
E Liven 《Acta veterinaria Scandinavica》1978,19(2):184-191
The activities of proteinases, lipases, amylases and the activities of proteinase inhibitors, as well as the numbers of Escherichia coli in the contents from the small intestine were examined for pigs suffering from colienterotoxaemia and for healthy pigs. Enzyme activities were determined using an agar diffusion test.Compared with healthy animals the activities of proteinases and amylases in diseased animals were reduced while lipases showed increased activity. In pathologically changed contents showing large numbers of E. coli, proteinases could not be demonstrated; however, proteinase inhibitors were found in these contents. In healthy animals, proteinase inhibitors were not demonstrated in ingesta-con-taining contents.In diseased animals, E. coli were found in large numbers in all parts of the small intestine. In healthy animals, E. coli was demonstrated especially in the posterior part of the small intestine and regularly in small numbers.The possible influence of digestive enzymes, especially proteinases and their inhibitors, on enterotoxins from E. coli is discussed. 相似文献
39.
详细阐述了听力训练在高职学生的英语学习中的重要作用以及高职学生在英语听力训练中存在的问题及采用的对策与方法。 相似文献
40.
设{εi,i≥1}为PA序列,Eεi=0,supE(ε^2j)〈∞,对某个r〉2及占〉δ,supE|εj|^r+δ〈∞,u(n)=O(n^(r-2)(r+δ)/2δ,在PA序列误差下,讨论了非参数回归函数加权核估计的相合性. 相似文献