目的探讨炎调方调过Fas/Caspase-8信号通路减轻脓毒症急性胃肠损伤小鼠炎症的机制。方法取70只BALB/c小鼠随机分为空白组、假手术组和造模小鼠组。通过盲肠结扎穿孔术(cecum ligation and puncture,CLP)构建脓毒症急性胃肠损伤小鼠模型...目的探讨炎调方调过Fas/Caspase-8信号通路减轻脓毒症急性胃肠损伤小鼠炎症的机制。方法取70只BALB/c小鼠随机分为空白组、假手术组和造模小鼠组。通过盲肠结扎穿孔术(cecum ligation and puncture,CLP)构建脓毒症急性胃肠损伤小鼠模型,将造模成功的小鼠随机分为模型组,炎调方低、中、高剂量组,ROCK抑制剂组。苏木素-伊红(HE)染色观察小鼠回肠组织病理学改变;ELISA法检测各组小鼠血清IL-17、IL-23水平;蛋白印迹法检测回肠组织Fas/Caspase-8信号通路蛋白Fas、FADD和Caspase-8的相对表达;TUNEL染色法检测回肠组织细胞凋亡情况。结果与空白组相比,模型组小鼠回肠组织肠黏膜萎缩明显、绒毛排列杂乱,可见断裂、脱落,上皮细胞细胞坏死脱落,炎症细胞浸润明显,小鼠血清中IL-17、IL-23水平升高(P<0.05),回肠组织中Fas、FADD和Caspase-8蛋白的表达升高(P<0.05),肠上皮细胞呈现明显的凋亡现象(P<0.05)。与模型组相比,炎调方组小鼠的回肠组织病理学改变均得到不同程度的改善,血清中IL-17、IL-23水平降低(P<0.05),且回肠组织中Fas、FADD和Caspase-8蛋白的表达降低(P<0.05),肠上皮细胞凋亡减少(P<0.05)。结论炎调方可以减轻肠黏膜组织损伤和肠道组织炎症反应,可能是通过调控Fas/Caspase-8信号通路抑制脓毒症急性胃肠损伤小鼠的肠上皮细胞凋亡来发挥作用的。展开更多
Planting at an optimum density and supplying adequate nitrogen（N） to achieve higher yields is a common practice in crop production, especially for maize（Zea mays L.）; however, excessive N fertilizer supply in maiz...Planting at an optimum density and supplying adequate nitrogen（N） to achieve higher yields is a common practice in crop production, especially for maize（Zea mays L.）; however, excessive N fertilizer supply in maize production results in reduced N use efficiency（NUE） and severe negative impacts on the environment. This research was conducted to determine the effects of increased plant density and reduced N rate on grain yield, total N uptake, NUE, leaf area index（LAI）, intercepted photosynthetically active radiation（IPAR）, and resource use efficiency in maize. Field experiments were conducted using a popular maize hybrid Zhengdan 958（ZD958） under different combinations of plant densities and N rates to determine an effective approach for maize production with high yield and high resource use efficiency. Increasing plant density was clearly able to promote N absorption and LAI during the entire growth stage, which allowed high total N uptake and interception of radiation to achieve high dry matter accumulation（DMA）, grain yield, NUE, and radiation use efficiency（RUE）. However, with an increase in plant density, the demand of N increased along with grain yield. Increasing N rate can significantly increase the DMA, grain yield, LAI, IPAR, and RUE. However, this increase was non-linear and due to the input of too much N fertilizers, the efficiency of N use at NCK（320 kg ha^（–1）） was low. An appropriate reduction in N rate can therefore lead to higher NUE despite a slight loss in grain production. Taking into account both the need for high grain yield and resource use efficiency, a 30% reduction in N supply, and an increase in plant density of 3 plants m^（–2）, compared to LD（5.25 plants m^（–2））, would lead to an optimal balance between yield and resource use efficiency.展开更多
数据流分类是数据流挖掘领域一项重要研究任务,目标是从不断变化的海量数据中捕获变化的类结构.目前,几乎没有框架可以同时处理数据流中常见的多类非平衡、概念漂移、异常点和标记样本成本高昂问题.基于此,提出一种非平衡数据流在线主...数据流分类是数据流挖掘领域一项重要研究任务,目标是从不断变化的海量数据中捕获变化的类结构.目前,几乎没有框架可以同时处理数据流中常见的多类非平衡、概念漂移、异常点和标记样本成本高昂问题.基于此,提出一种非平衡数据流在线主动学习方法(Online active learning method for imbalanced data stream,OALM-IDS).AdaBoost是一种将多个弱分类器经过迭代生成强分类器的集成分类方法,AdaBoost.M2引入了弱分类器的置信度,此类方法常用于静态数据.定义了基于非平衡比率和自适应遗忘因子的训练样本重要性度量,从而使AdaBoost.M2方法适用于非平衡数据流,提升了非平衡数据流集成分类器的性能.提出了边际阈值矩阵的自适应调整方法,优化了标签请求策略.将概念漂移程度融入模型构建过程中,定义了基于概念漂移指数的自适应遗忘因子,实现了漂移后的模型重构.在6个人工数据流和4个真实数据流上的对比实验表明,提出的非平衡数据流在线主动学习方法的分类性能优于其他5种非平衡数据流学习方法.展开更多
文摘目的探讨炎调方调过Fas/Caspase-8信号通路减轻脓毒症急性胃肠损伤小鼠炎症的机制。方法取70只BALB/c小鼠随机分为空白组、假手术组和造模小鼠组。通过盲肠结扎穿孔术(cecum ligation and puncture,CLP)构建脓毒症急性胃肠损伤小鼠模型,将造模成功的小鼠随机分为模型组,炎调方低、中、高剂量组,ROCK抑制剂组。苏木素-伊红(HE)染色观察小鼠回肠组织病理学改变;ELISA法检测各组小鼠血清IL-17、IL-23水平;蛋白印迹法检测回肠组织Fas/Caspase-8信号通路蛋白Fas、FADD和Caspase-8的相对表达;TUNEL染色法检测回肠组织细胞凋亡情况。结果与空白组相比,模型组小鼠回肠组织肠黏膜萎缩明显、绒毛排列杂乱,可见断裂、脱落,上皮细胞细胞坏死脱落,炎症细胞浸润明显,小鼠血清中IL-17、IL-23水平升高(P<0.05),回肠组织中Fas、FADD和Caspase-8蛋白的表达升高(P<0.05),肠上皮细胞呈现明显的凋亡现象(P<0.05)。与模型组相比,炎调方组小鼠的回肠组织病理学改变均得到不同程度的改善,血清中IL-17、IL-23水平降低(P<0.05),且回肠组织中Fas、FADD和Caspase-8蛋白的表达降低(P<0.05),肠上皮细胞凋亡减少(P<0.05)。结论炎调方可以减轻肠黏膜组织损伤和肠道组织炎症反应,可能是通过调控Fas/Caspase-8信号通路抑制脓毒症急性胃肠损伤小鼠的肠上皮细胞凋亡来发挥作用的。
基金the National Natural Science Foundation of China(3117 1497)the National Basic Research Program of China(973 Program,2011CB100105)+1 种基金the National Food Science and Technology of High Yield Program of China(2011BAD16B09)the Special Fund for Agro-scientific Research in the Public Interest of China(201203096)
文摘Planting at an optimum density and supplying adequate nitrogen（N） to achieve higher yields is a common practice in crop production, especially for maize（Zea mays L.）; however, excessive N fertilizer supply in maize production results in reduced N use efficiency（NUE） and severe negative impacts on the environment. This research was conducted to determine the effects of increased plant density and reduced N rate on grain yield, total N uptake, NUE, leaf area index（LAI）, intercepted photosynthetically active radiation（IPAR）, and resource use efficiency in maize. Field experiments were conducted using a popular maize hybrid Zhengdan 958（ZD958） under different combinations of plant densities and N rates to determine an effective approach for maize production with high yield and high resource use efficiency. Increasing plant density was clearly able to promote N absorption and LAI during the entire growth stage, which allowed high total N uptake and interception of radiation to achieve high dry matter accumulation（DMA）, grain yield, NUE, and radiation use efficiency（RUE）. However, with an increase in plant density, the demand of N increased along with grain yield. Increasing N rate can significantly increase the DMA, grain yield, LAI, IPAR, and RUE. However, this increase was non-linear and due to the input of too much N fertilizers, the efficiency of N use at NCK（320 kg ha^（–1）） was low. An appropriate reduction in N rate can therefore lead to higher NUE despite a slight loss in grain production. Taking into account both the need for high grain yield and resource use efficiency, a 30% reduction in N supply, and an increase in plant density of 3 plants m^（–2）, compared to LD（5.25 plants m^（–2））, would lead to an optimal balance between yield and resource use efficiency.
文摘数据流分类是数据流挖掘领域一项重要研究任务,目标是从不断变化的海量数据中捕获变化的类结构.目前,几乎没有框架可以同时处理数据流中常见的多类非平衡、概念漂移、异常点和标记样本成本高昂问题.基于此,提出一种非平衡数据流在线主动学习方法(Online active learning method for imbalanced data stream,OALM-IDS).AdaBoost是一种将多个弱分类器经过迭代生成强分类器的集成分类方法,AdaBoost.M2引入了弱分类器的置信度,此类方法常用于静态数据.定义了基于非平衡比率和自适应遗忘因子的训练样本重要性度量,从而使AdaBoost.M2方法适用于非平衡数据流,提升了非平衡数据流集成分类器的性能.提出了边际阈值矩阵的自适应调整方法,优化了标签请求策略.将概念漂移程度融入模型构建过程中,定义了基于概念漂移指数的自适应遗忘因子,实现了漂移后的模型重构.在6个人工数据流和4个真实数据流上的对比实验表明,提出的非平衡数据流在线主动学习方法的分类性能优于其他5种非平衡数据流学习方法.
