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141.
ADELIJIANG Wusiman DELIBAIER NUERAILI Maitiniyazi BUHELIQIANMU Yiming SAIFUDING Abula 《中国畜牧兽医》2016,43(7):1869-1875
To research on polysaccharides from Lagenaria siceraria (Molina) Standl.against Newcastle disease virus (NDV).Total polysaccharide and four different solvent extractions of Lagenaria siceraria (Molina) Standl.were extracted by the methods of hot water extraction and ethanol precipition in this study.The content of polysaccharide was measured by phenol-sulfuric acid method and infrared spectroscopy method.The safe concentration and growth of chick embryo fibroblast (CEF) were assayed by MTT method,in order to facilitated the comparison under the same level,the safe concentration was united as 78.125 μg/mL.Under the safety range of concentration,detected the block-virus activity,anti-virus activity and virus-killing activity of polysaccharides through the ways of pre-adding polysaccharides,post-adding polysaccharides and adding polysaccharides with NDV.The results showed that the direct inactivation and propagation inhibition activity of total polysaccharide and four different solvent extractions were stronger than anti-absorption function.Anti-virus inhibition rate of 70%,80% gradient alcohol precipitation of polysaccharides from Lagenaria siceraria (Molina) Standl.(LSP70,LSP80) and total polysaccharide (LSPt)were 40.41%,44.54% and 61.85%,virus-killing inhibition rate were 44.74%,58.76% and 59.38%.LSP80 had the highest virus inhibition rate as 37.14% in the block-virus activity of those five polysaccharides.In summary,70%,80% gradient alcohol precipitation and total polysaccharide in polysaccharides possessed better activity and would be as the materials for further research. 相似文献
142.
Since the first publication on “regional ileitis”, the relevance of this chronic inflammatory disease condition termed finally as Crohn's disease is continuously increasing. Although we are beginning to comprehend certain aspects of its pathogenesis, many facets remain unexplored. Host's gut microbiota is involved in a wide range of physiological and pathological processes including immune system development, and pathogen regulation. Further, the microbiome is thought to play a key role in Crohn's disease. The presence of Crohn's-associated variants of NOD2 and ATG16L genes appears to be associated not only with alterations of mucosal barrier functions, and bacterial killing, but the gut microbiota, as well, reflecting a potential relationship between the host's genotype and intestinal dysbiosis, involved in disease etiology. This review aims to characterize some exciting new aspect of Crohn's disease pathology, focusing mainly on the role of intestinal microbes, and their interplay with the immune system of the host. 相似文献
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144.
土地采用保护性耕作方法,可有效的防止水土流失,增加土壤蓄水能力,提高雨水利用率,培肥地利,增加土壤有机质,减少耕作次数,降低生产成本,各种农作物增产明显。 相似文献
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146.
钱玉光 《农业图书情报学刊》2011,23(5):183-185
通过问卷调查方式对苏北连云港地区灌云县农村小学生的阅读状况、阅读需求和服务进行专题调研,并对相关数据进行统计分析,试图从中探究农村小学生阅读的共性特征和存在的问题,为农村青少年阅读活动的进一步开展提供参考依据。 相似文献
147.
为了探寻影响油茶高接换冠后枯桩的相关因素,为今后油茶高接换冠技术改良提供理论依据,调查研究了嫁接方法、接穗品种、砧木粗度、留截高度和嫁接方位等因素对油茶高接换冠后枯桩现象的影响。结果表明:5种因素对油茶枯桩程度影响极显著。其中,采用插皮腹接、砧木直径2~6 cm枯桩程度最低;采用‘华硕’和‘湘林XLJ14’其枯桩程度显著低于其它品种;留截高度越低枯桩程度越低;嫁接方位在外侧枯桩程度最低。偏相关分析结果表明,留截高度对油茶枯桩程度的影响最大;其次是嫁接方法、砧木直径和嫁接品种;而嫁接方位对油茶枯桩程度的影响最小。 相似文献
148.
RJ Barnewall IB Marsh PMV Cusack F Galea N Sales JC Quinn 《Australian veterinary journal》2023,101(6):254-257
Bovine respiratory disease (BRD) exerts a major impact on the beef cattle industry nationally and worldwide, with a range of aetiological factors impacting its pathogenesis. Previous research has focussed on an increasing number of bacteria and viruses that have been shown to play a role in eliciting disease. Recently, additional agents have been emerging as potential contributors to BRD, including the opportunistic pathogen Ureaplasma diversum. To determine if U. diversum was present in Australian feedlot cattle and if that presence was linked to BRD, nasal swabs were collected from a cohort of 34 hospital pen animals and compared to 216 apparently healthy animals sampled contemporaneously at feedlot induction and again after 14 days on feed at an Australian feedlot. All samples were subjected to a de novo polymerase chain reaction (PCR) assay targeting U. diversum in combination with other BRD agents. U. diversum was detected at a low prevalence in cattle at induction (Day 0: 6.9%, Day 14: 9.7%), but in a significantly greater proportion of cattle sampled from the hospital pen (58.8%). When considering the presence of other BRD-associated agents, co-detection of U. diversum and Mycoplasma bovis was most common in hospital pen animals receiving treatment for BRD. These findings suggest that U. diversum may be an opportunistic pathogen involved in the aetiology of BRD in Australian feedlot cattle, in combination with other agents, with further studies are warranted to identify if a causal relationship exists. 相似文献
149.
辽宁省海城地区2011年突发的杨树烂皮病,危害严重,面积达2549hm2,阐述了杨树烂皮病发生危害情况,分析了突发原因,提出了防治对策。 相似文献
150.