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31.
Qiu-yan Chang Fu-cheng Guo Xue-rui Li Jian-hua Zhou Xuepeng Cai Qiuwei Pan Xiao-xia Ma 《Veterinary research communications》2018,42(4):309-313
Peste des petits ruminants virus (PPRV) causes highly contagious diseases in domestic and particular wild small ruminants, leading to substantial economic loss. The development of effective and cheap antiviral medications shall help to circumvent this emerging burden. In this study, we found that ribavirin, a competitive inosine-5’-monophosphate dehydrogenase (IMPDH) inhibitor, significantly inhibits the replication of PPRV. As IMPDH is a key enzyme in purine nucleotide synthesis, supplementation of exogenous guanosine attenuate the anti-PPRV effect of ribavirin. Interestingly, an uncompetitive IMPDH inhibitor, mycophenolic acid (MPA), exerted more potent antiviral effect again PPRV. Similarly, this effect was largely restored upon supplementation of guanosine. Thus, we have demonstrated that the IMPDH inhibitors ribavirin and MPA combat PPRV infection through purine nucleotide depletion. Because both regimens have been widely used in the clinic for treating viral infection or organ rejection in transplantation patients for decades, respectively, repurposing these existing safe and cheap medications may provide a new avenue for combating PPRV infection. 相似文献
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Effect of gut stress induced by oxidized wheat gluten on the growth performance,gut morphology and oxidative states of broilers 下载免费PDF全文
R. B. Liao H. J. Yan G. H. Liu S. Zhang W. H. Chang W. Liu C. H. Lin X. Y. Huang H. Y. Cai 《Journal of animal physiology and animal nutrition》2018,102(2):e849-e855
This study was to investigate the effect of oxidized wheat gluten (OG) on growth performance, gut morphology and its oxidative states of broilers. One hundred and eighty‐day‐old male broilers (10 chicks/pen) were randomly allocated into three dietary treatments: control diet (CON), diet with 8% wheat gluten (WG) and diet with 8% OG with six pens/treatment. Body weight (BW) (21 and 35 days) and average daily gain (ADG) (1–21 days and 22–35 days) decreased (p < .05) and feed conversion ratio (FCR) (1–21 days and 22–35 days) increased (p < .05) in OG treatment. Feed intake (FI) decreased (p < .05) in WG and OG treatments during 22–35 days. However, FI was not influenced by dietary treatments during 1–21 days (p > .05). The OG‐fed broilers had a lower faecal pH value (p < .05) and higher faecal moisture content (p < 05) at 14, 21, 28 and 35 days. Villus height, crypt depth and V/C value were not different (p > .05) among treatments at 21 and 35 days. Lipid peroxidation (LPO) (21 and 35 days) and malondialdehyde (MDA) (35 days) content in crop of OG treatment increased (p < .05). Oxidized glutathione (GSSG) (21 days), LPO (21 and 35 days) and MDA (21 and 35 days) content in ileum of OG treatment increased (p < .05). The reduced glutathione/oxidized glutathione (GSH/GSSG) (21 days) and (GSH) (35 days) in ileum of OG treatment decreased (p < .05). The present findings indicate that OG might be a stressor for broiler gut, which could induce oxidative stress both in crop and in ileum, and the diarrhoea as well. The growth performance of broiler was consequently depressed. 相似文献
34.
基质对黑果腺肋花楸幼苗生长的影响 总被引:1,自引:0,他引:1
以黑果腺肋花楸(Aronia melanocarpa)为试验材料,选用田园土、泥炭土、珍珠岩和黄沙,采用正交试验设计,研究不同基质配比对黑果腺肋花楸成苗率以及幼苗形态指标和生理指标的影响。结果表明,不同育苗基质对黑果腺肋花楸出苗率、苗高、地径、主根长、侧根数和高径比等形态指标以及根系活力、可溶性糖、淀粉和蛋白质等生理指标的影响差异显著,综合分析各项指标,筛选出适合黑果腺肋花楸容器育苗的栽培基质为田园土(40%)+泥炭土(30%)+黄沙(30%)、田园土(40%)+珍珠岩(30%)+黄沙(30%)、田园土(40%)+泥炭土(30%)+珍珠岩(30%)和田园土(60%)+泥炭土(20%)+黄沙(20%)。 相似文献
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为了研究不同精粗比日粮对广河羊羔肉品质的影响,在广河县羔羊肉生产区,选择不同精粗比饲喂的6月龄健康陶寒杂交(陶赛特羊♂×小尾寒羊♀)断奶去势公羔各3只进行屠宰,取股二头肌、背最长肌、肱二头肌3个部位肌肉和肾周脂肪、皮下脂肪、尾部脂肪3个部位脂肪,用气象色谱法分析其脂肪酸的种类及含量。结果表明,在所有组织中均检测出38种脂肪酸,其中饱和脂肪酸17种,不饱和脂肪酸21种。脂肪组织中饲喂低精粗比日粮的亚油酸(C18∶2n6c)、α-亚麻酸(C18∶3n3)、饱和脂肪酸(SFA)、多不饱和脂肪酸(PUFA)及其与饱和脂肪酸比值(P/S)、n3系多不饱和脂肪酸和n6系多不饱和脂肪酸均显著高于饲喂高精粗比日粮(P<0.05);饲喂低精粗比日粮的所有组织中花生四烯酸(C20∶4)的含量显著高于饲喂高精粗比日粮(P<0.05);与饲喂高精粗比日粮的羊羔肉相比,饲喂低精粗比日粮既节省了生产成本又明显改善和提高了羊羔肉中脂肪酸的营养价值。 相似文献
36.
农户购买农资时面临多样化的购买渠道,而信息化与社会网络是影响农户农资购买渠道选择的重要因素。本文利用陕西、甘肃、山东和云南四省农户调研数据,比较了公司直销与农资零售店两种购买渠道的差异,运用二元 Logit 模型和中介效应模型,分析信息化与社会网络对农户农资购买渠道选择的影响。结果表明,农户选择公司直销与农资零售店的比例分别为10.1%和89.9%,即大多数农户选择农资零售店购买农资。信息利用对农户选择公司直销渠道具有显著正向影响;从亲戚和朋友两个维度测量社会网络,发现宗族型社会网络对农户选择公司直销渠道产生了正向影响,朋友圈型社会网络影响不显著;农户农资市场信息认知在信息利用促进农户选择公司直销渠道中发挥部分中介效应。因此,政府应加强农村信息基础设施建设,培养农户信息利用能力。公共信息供给过程中扩大宣传对象群体,促使信息在农户社会网络中有效扩散传播。建设农资企业与农户间有效的信息交流平台,打破信息壁垒,从而帮助农户改进农资购买决策。 相似文献
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38.
通过对吉林省国有林场职工参加基本养老保险、基本医疗保险等五险情况的调查,指出其存在参保比率低、缴费标准低、欠费额度大、待遇不一致和地区间不平衡等问题。到2013年底,全省国有林场已参加社会保险单位累计欠缴基本养老保险保费15.2亿元,未参保职工若全部纳入保险范围,尚需补缴保费63.2亿元,数额十分巨大。建议国家尽快出台政策解决企事业单位参保待遇不同问题,同时省级财政和中央财政资金补助要保障最低线,对按社会平均工资60%下限标准缴费部分要全额保障。 相似文献
39.
为探讨吉林延龄草种子内源抑制物质生理活性及种子中抑制物质的去除方法,采用乙酸乙酯、甲醇、水提取吉林延龄草种子并测定其提取物对白菜、水稻幼苗生长的抑制活性,用温水(25,35,45℃)浸种并测定各批次浸提液抑制活性,结果表明,吉林延龄草种子浸提液(乙酸乙酯提取液除外)对白菜幼根及胚轴,水稻幼根均有显著抑制作用,且抑制物质的活性随着提取物浓度的增加而增强,吉林延龄草种子水提取液(C)对白菜和水稻幼苗生长的抑制活性高于甲醇提取液(B)的生物活性,吉林延龄草种子乙酸乙酯提取液对白菜和水稻幼苗无显著抑制作用(p>0.05),吉林延龄草种子经乙酸乙酯、甲醇溶液提取后,再经蒸馏水提取获得的水提液Ⅱ(E)对白菜和水稻幼苗生长的抑制活性减弱;温水浸泡可将其内源抑制物质浸提出来,且随着浸种时间的增加,浸提液对白菜幼根及胚轴的抑制作用呈现先增加而后逐渐降低的趋势.25℃蒸馏水浸泡种子第5天浸提液抑制作用达到最大,对白菜幼根及胚轴的抑制作用分别达到65.89%和25.69%,35℃蒸馏水浸泡种子第3天浸提液抑制作用达到最大,对白菜幼根及胚轴的抑制作用分别达到82.14%和59.93%,45℃蒸馏水浸泡种子第2天浸提液抑制作用达到最大,对白菜幼根及胚轴的抑制作用分别达到90.62%和83.86%.综合分析表明,吉林延龄草种子中存在活性较高的内源抑制物,用45℃温水浸泡可有效除去种子内源抑制物质. 相似文献
40.
Technology transfer is a conscious knowledge transfer and diffusion, which can promote the coordinated configuration and balanced development of technological innovation elements in geographical space. From the perspective of “space of flow”, the technology transfer network is constructed. Utilizing patent technology transaction data from 2018, this study analyzes the agglomeration differentiation and spatial polarization patterns of technology transfer from network nodes, network layers, and network partition in Guangdong–Hong Kong–Macao Greater Bay Area. The conclusions are as follows: (1) The agglomeration of technology transfer is remarkable in the network, showing “two poles and two strong” as well as proximity advantages; Shenzhen and Guangzhou have become spatial poles within the network. (2) The Matthew effect is prominent and technology transfer at the spatial level is largely caused by core node interactions, while core-edge hierarchical transmission mechanisms and geographical proximity contact characteristics are gradually developing. (3) Differences in roles between the plates are pronounced, and there is an agglomeration effect within a plate and between plates, as well as clear spillover effects. 相似文献