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31.
Adherence of Actinobacillus pleuropneumoniae serotype 1 to swine buccal epithelial cells involves fibronectin 下载免费PDF全文
Roberto Hamer-Barrera Delfino Godínez V. Idalia Enríquez Sergio Vaca-Pacheco Rodrigo Martínez-Zú?iga Patricia Talamás-Rohana Francisco Suárez-Güemez Mireya de la Garza 《Canadian journal of veterinary research》2004,68(1):33-41
The swine pathogen Actinobacillus pleuropneumoniae serotype 1 was investigated for its ability to adhere to swine, rat, and human buccal epithelial cells (BEC). The highest number of bacteria adhered was to swine BEC. This binding ability was affected by heating, extreme pH, treatment with sodium dodecyl sulfate, ethylenediamine tetraacetate, or periodate, and proteolysis, suggesting that cell-surface glycoproteins participate in adherence and that adherence is based mostly on ionic interactions. Mannose and swine fibronectin may play a direct role in this interaction. Convalescent-phase serum from naturally infected pigs inhibited the adhesion. There was a correlation between bacterial pathogenicity as well as host specificity and the capacity for adherence to swine BEC. Adhesion to swine BEC provides a convenient method to study in vitro the adherence of A. pleuropneumoniae and other pathogens of the pig respiratory tract. 相似文献
32.
Effects of dietary lysozyme levels on growth performance,intestinal morphology,non‐specific immunity and mRNA expression in weanling piglets 下载免费PDF全文
Jiatao Zhu Xiaoxue Pang Zhengfeng Fang Yan Lin Lianqiang Che Shengyu Xu Jian Li Yiming Huang Xiang Su De Wu 《Animal Science Journal》2016,87(3):411-418
The aim of the present study was to determine the effect of dietary lysozyme levels on growth performance, gut health and non‐specific immunity of weanling piglets. A total of 150 weanling piglets were allocated to six treatments. The piglets were fed the same basel diet supplemented with 0, 30, 60, 90 and 120 mg/kg lysozyme as well as antibiotics for 28 days. From day 14 to day 28 of dietary treatment, piglets fed 90 mg/kg lysozyme had greater average daily gain than piglets fed control diet. During the whole experimental period, piglets fed 120 mg/kg lysozyme tended to have greater average daily gain than piglets fed control diet. Compared with piglets fed control diet, piglets fed diets containing antibiotics and 90 mg/kg lysozyme had greater villus height to crypt depth ratio in duodenum and jejunum. Additionally, dietary supplementation of 60 and 90 mg/kg lysozyme as well as antibiotics enhanced the phagocytic activity of peritoneal macrophages in piglets. In conclusion, dietary lysozyme can accelerate the growth of weanling piglets by improving gut health and non‐specific immunity and supplementing 90 mg/kg lysozyme is as effective as antibiotics (20 mg/kg colistin sulphate + 50 mg/kg kitasamycin) in improving the growth performance of weanling piglets. 相似文献
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Mi Jeong Park Jienny Lee Jeong Su Byeon Da-Un Jeong Na-Yeon Gu In-Soo Cho Sang-Ho Cha 《Veterinary research communications》2018,42(3):171-181
Mesenchymal stem cells (MSCs) are useful candidates for tissue engineering and cell therapy fields. We optimize culture conditions of equine adipose tissue-derived MSCs (eAD-MSCs) for treatment of horse fractures. To investigate enhancing properties of three-dimensional (3D) culture system in eAD-MSCs, we performed various sized spheroid formation and determined changes in gene expression levels to obtain different sized spheroid for cell therapy. eAD-MSCs were successfully isolated from horse tailhead. Using hanging drop method, spheroid formation was generated for three days. Quantitative real-time PCR was performed to analyze gene expression. As results, expression levels of pluripotent markers were increased depending on spheroid size and the production of PGE2 was increased in spheroid formation compared to that in monolayer. Ki-67 showed a remarkable increase in the spheroid formed with 2.0?×?105 cells/drop as compared to that in the monolayer. Expression levels of angiogenesis-inducing factors such as VEGF, IL-6, IL-8, and IL-18 were significantly increased in spheroid formation compared to those in the monolayer. Expression levels of bone morphogenesis-inducing factors such as Cox-2 and TGF-β1 were also significantly increased in spheroid formation compared to those in the monolayer. Expression levels of osteocyte-specific markers such as RUNX2, osteocalcin, and differentiation potential were also significantly increased in spheroid formation compared to those in the monolayer. Therefore, spheroid formation of eAD-MSCs through the hanging drop method can increases the expression of angiogenesis-inducing and bone morphogenesis-inducing factors under optimal culture conditions. 相似文献
35.
在最小方差检测策略基础上,提出了用于可靠性估计的自适应检测算法.通过比较可知,自适应检测算法对可靠性估计的方差值小于操作框架均匀分布的随机检测方法和操作框架指定分布的一般检测方法的值.结果表明了自适应检测算法是有效的. 相似文献
36.
亏缺灌溉对成龄库尔勒香梨产量与根系生长的影响 总被引:4,自引:0,他引:4
研究了亏缺灌溉对成龄库尔勒香梨树营养生长、果实生长与吸收根系分布的影响。香梨的生育中期,设计了4种土壤水分亏缺(灌前土壤水势下限):轻度胁迫(-100 kPa)、中度胁迫(-200 kPa)、重度胁迫(-300 kPa)和对照(-50 kPa)。灌溉系统为地表滴灌。试验结果表明,亏缺灌溉显著地减少了夏季剪枝量,提高了果实产量。充分灌溉条件下,香梨树根长密度从树行由内向外呈递减趋势,滴灌促进了湿润体内的吸收根系的发育;距树行0.5 m,根长密度随着深度的增加而减少;距树行1 m至1.5 m,根长密度随着深度的增加而增加;距树行2 m的非灌溉区,根长密度在垂直方向上变化不显著。为适应滴灌湿润体内水分胁迫,香梨树在湿润体内及非灌溉区的吸收根系的分布均发生了显著的调整。适度水分胁迫下的根长密度增加对香梨产量有促进作用。 相似文献
37.
通过对肉制品加工的各种原辅材料及加工的各个环节入手,分析了可能引起肉制品出水的原因,并从原辅材料的选用及加工工艺的改进和优化方面,提出了对肉制品出水问题控制的方法与措施。 相似文献
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鉴于独立运行的风力发电系统或太阳能发电系统都有其自身的局限性,该文选择了结合风力发电和太阳能发电优点的风光互补发电系统作为研究对象,通过对内蒙古锡林郭勒盟农牧区的风能和太阳能资源进行分析,力求实现系统优化及其推广应用。 相似文献
39.
苹果霉心病可见/近红外透射能量光谱识别方法 总被引:1,自引:0,他引:1
针对苹果霉心病从外表无法识别的难题,提出基于可见/近红外透射能量光谱进行快速无损识别的模型和方法。在200~1 100 nm波段内采集了200个苹果的透射能量光谱数据,随机选取140个样品作为训练集,剩余60个样品作为测试集。用平滑法和多元散射校正对光谱数据进行预处理。基于全光谱、连续投影算法(SPA)提取的12个特征波长、主成分分析(PCA)提取的9个主成分,分别建立了偏最小二乘判别法、误差反向传播人工神经网络和支持向量机(SVM)识别模型。实验结果说明,应用PCA-SVM建立的模型识别性能最优,该模型对测试集和训练集中霉心病果和健康果的识别正确率分别为99.3%和96.7%。基于SPA和PCA所建模型的输入变量数仅相当于基于全光谱所建模型输入变量数的0.99%和0.74%,极大降低了模型的复杂度。研究结果表明,该方法是可行的且具有较高识别准确度,为苹果在线内部品质分级和便携式苹果霉心病检测仪的研究提供了技术依据。 相似文献
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