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81.
核桃 (Juglansregia)‘No . 12 0’品系授粉 7~ 8周的幼胚胚轴与子叶在含不同植物生长调节剂组合的诱导培养基上培养 4周后转移至无植物生长调节剂的继代培养基上培养 ,不同发育时期的体细胞胚直接形成于胚轴与子叶表面。子叶与胚轴分别在KT 2mg/L BA1mg/L IBA 0 .0 1mg/L与 2 ,4 D 2mg/L KT 1mg/L的组合的诱导下体细胞胚胎发生频率最高。体细胞胚经 3~ 5℃低温处理 2个月 ,31.6%的体细胞胚能发育成正常生长的植株  相似文献   
82.
荔枝果皮的褐变一直是商业上的一个主要采后问题。大多数人认为褐变是由于果实失水后多酚氧化酶(PPO)活性增加引起的,它导致了花青苷的迅速降解,使果变褐。然而,支持此理论的实验证据很少。最近,澳大利亚和以色列着重研究果皮液泡的PH值对花青苷颜色和稳定性的影响。本文综述了研究荔枝果皮褐变的方法,并针对目前流行的PPO引起花青苷降解的理论提出一些疑问。  相似文献   
83.
Fibroblast growth factor 21(FGF21) has been identified as an important regulator of carbohydrate and lipid metabolism, which plays an important role for metabolic regulation, particularly under conditions of energy deprivation or stress conditions. Dairy cows are subjected to a negative energy balance and various kinds of stress particularly during the periparturient phase and during early lactation. It has been shown that the plasma concentration of FGF21 in dairy cows is dramatically increased...  相似文献   
84.
Background: Alternative feedstuffs may contribute to reducing feed costs of pig production. But these feedstuffs are typically rich in fiber and resistant starch(RS). Dietary fibers and RS are fermented in the gastrointestinal tract(GIT) and modulate the microbial community. Certain microbes in the GIT can promote host health, depending on the type of fermentation substrates available. In this study, six alternative feedstuffs(three starchy: Okinawan sweet potato, OSP; yam, and taro, and three f...  相似文献   
85.
Background: In early lactation, bovine mammary epithelial cells undergo serious metabolic challenges and oxidative stress both of which could be alleviated by activation of autophagy. Nuclear factor erythroid 2 related factor 2(NFE2L2), a master regulator of cellular redox homeostasis, plays an important role in the regulation of autophagy and oxidative stress. Thus, the objective of this study was to investigate the role of NFE2L2-mediated autophagy on oxidative stress of bovine mammary epithel...  相似文献   
86.
Background: The high dependence of intensive ruminant production on soybean meal and the environmental impact of this crop encourage the search for alternative protein-rich feeds. The use of insects seems promising, but the extent of their ruminal protein degradation is largely unknown. This parameter has major influence not only on N utilization efficiency but also on the environmental burden of ruminant farming. In addition, although assessing ruminal N degradation represents a key first step ...  相似文献   
87.
Antimicrobials have been widely used to prevent and treat infectious diseases and promote growth in food-production animals. However, the occurrence of antimicrobial resistance poses a huge threat to public and animal health, especial y in less developed countries where food-producing animals often intermingle with humans. To limit the spread of antimicrobial resistance from food-production animals to humans and the environment, it is essential to have a comprehensive knowledge of the role of th...  相似文献   
88.
Background: Nutritional value of proteins in feed ingredients can be negatively affected by hydrothermal processing, which causes large variation in the bioavailability of amino acids(AA) and negatively affects animal productive performance. Supplementation of exogenous proteases could increase the rate of digestion of damaged proteins, thereby increasing overall AA digestibility and bioavailability. The aim was to determine the effect of exogenous protease supplementation on the apparent ileal ...  相似文献   
89.
Background: Consumption of resistant starch(RS) has been associated with various intestinal and systemic health benefits, but knowledge of its effects on intestinal health and inflammatory response in stressed birds is limited.Here, we examined how dietary RS supplementation from 12% raw potato starch(RPS) modulated inflammatory severity induced by lipopolysaccharide(LPS) in meat ducks.Results: LPS administration at 14, 16, and 18 d(chronic challenge) decreased body weight(BW) and glucagon-like ...  相似文献   
90.
Raising Min pigs(MPs) in northern China is challenging, because of harsh environmental conditions in winter. There is a hypothesis that MPs can tolerate cold stress better than Large White pigs(LWPs) and their oocyte competence is particularly protected. Over a period of 3 years, multiple cohorts of MPs and LWPs under different environmental conditions were studied in this paper. Follistatin(FST) serum level was used as a marker for swine oocyte competence. Oocytes were collected from the swine ...  相似文献   
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