一种弯管加热成型回转系统的设计

随着弯管在各个行业的需求量急剧增加,对弯管成型的工艺以及设备的研究已渐渐引发热潮.论文在北京国电富通公司对弯管成型工艺流程的实验基础上,对于弯管成型的自动化工艺进行了研究,设计了一种流水线回转系统,为今后弯管成型的自动化设备的设计提供参考.     

电解多功能联合机组打壳装置改造

介绍了如何对包铝装置低位电解多的联合机组打壳装置进行改造。实现用多功能天车自动打击135kA预焙=电解槽阳极中缝的有关情况和经验。     

Elp3 modulates neural crest and colorectal cancer migration requiring functional integrity of HAT and SAM domains

Cell migration is a finely tuned biological process that often involves epithelial-mesenchymal transition (EMT).EMT is typically characterized by the upregulation of mesenchymal markers such as Snail1. This process has been shownto be of critical importance to normal developmental processes, including neural crest migration and invasion.Interestingly, similar mechanisms are utilized in disease processes, such as tumor metastasis and migration. Notably,EMT and EMT-like processes confer tumor cells with the ability to migrate, invade, and adopt stem cell-likeproperties that largely account for immunosuppression and tumor recurrence. Therefore, identifying sensitive EMTmarkers may contribute to cancer prognosis and diagnosis in many facets. Previously, we showed that Elp3 plays anessential role during neural crest migration by stabilizing Snail1. In the current study, we further elucidate themolecular mechanism underlying colorectal cancer migration. We found that mElp3 exerted an identical function toxElp3 in modulating neural crest migration, and both HAT and SAM domains are imperative during this migratoryprocess. Interestingly, overexpression of mElp3 in SW480 cells promoted cell migration and invasion, and we furthershowed that Elp3 stabilized Snail1 requiring integrity of both SAM and HAT domains. Our findings warrant furtherexploration of the specific target of Elp3 in cancer cells.     

四氢姜黄素经PI3K/Akt信号通路对人血小板活化和聚集的调控作用

目的：探讨姜黄素的主要肠道代谢物四氢姜黄素（tetrahydrocurcumin,THC）对血小板活化和聚集的影响及其可能的分子机制。方法：在体外实验中,用不同浓度的THC（0、0.5、1、10 μmol/L）提前与健康人纯化血小板共同孵育40 min,然后加入凝血酶激活血小板2 min,用流式细胞术测定血小板表面CD62P和CD63的表达量,用酶联免疫吸附法测定血小板释放血小板因子-4（platelet factor-4,PF4）和趋化因子配体-5（chemokine ligand 5,CCL5）水平,用血小板聚集仪检测血小板释放ATP水平和血小板最大聚集率,用Western blot蛋白免疫印迹法检测血小板磷酸肌醇-3-激酶（phosphoinositide 3-kinase,PI3K）和Akt蛋白的磷酸化水平。结果：与模型组（血小板悬液中加入0.05%二甲基亚砜）相比,THC能抑制凝血酶诱导的血小板表面CD62P和CD63的表达,抑制PF4、CCL5和ATP的释放,降低血小板最大聚集率,下调PI3K和Akt蛋白的磷酸化水平,且呈浓度依赖效应,其中10 μmol/L的浓度下作用效果显著（P＜0.01、P＜0.001）。PI3K的特异性激动剂740 Y-P可部分逆转THC对PF4和CCL5释放和血小板聚集的抑制作用（P＜0.05、P＜0.01）。结论：THC具有显著抑制血小板活化和聚集的作用,其机制可能是THC可下调PI3K/Akt介导的信号通路。     

移栽期对烤烟化学成分及成熟烟叶组织结构的影响

研究了移栽期对烤烟常规化学成分,致香物质,石油醚提取物及成熟烟叶组织结构的影响。结果表明:不同移栽期对还原糖、总糖、总氮影响较小,对烟碱与致香性物质的影响较大;各处理之间石油醚提取物含量依次为:T3>T4>T2>T1>T5>T6。成熟烟叶组织中栅栏组织厚度与海绵组织厚度均呈先下降后趋于平缓的趋势,上、下表皮细胞厚度的差异不显著。     

Genetic evidence for cell death mediated by nerve growth factor and the neurotrophin receptor p75 in the developing mouse retina and spinal cord

The role of nerve growth factor (NGF) and of the neurotrophin receptor p75 (p75(NTR)) in programmed cell death was investigated in the retina and the spinal cord of mouse embryos. Large numbers of cells express p75(NTR) in and along the developing optic nerve and in the mantle zone of the spinal cord. In embryos carrying deletions in the ngf or the p75(NTR) gene, cell death was reduced in the retina and in the spinal cord. Increased numbers of Islet-1-immunoreactive cells were detected in the dorsal spinal cord, and the mantle zone was enlarged in both mutants. These results indicate that NGF/p75(NTR)-dependent mechanisms are used to remove cells when axonal tracts elongate in developing neuroepithelia.     

环境因子的交互作用对蜡状芽孢杆菌消长规律的影响

以肉制品中常见的蜡状芽孢杆菌为研究对象,采用中心组合设计方法考察温度（88～96℃）、pH（5．1～6．3）、氯化钠浓度（1．5％～3．5％,w/v）和初始菌数（4～7log10 CFU／mL）的交互作用对蜡状芽孢杆菌消长规律的影响。不同环境因子作用下菌株D值的响应面分析结果显示,响应面回归方程中无失拟因素存在,预测值与实测值达到较好的拟合（R^2=0．9644）。不同环境因子作用下蜡状芽孢杆菌消长规律的方差分析显示,环境因子的交互作用有极显著影响（P〈0．01）,其中温度和pH的影响达到极显著水平（P〈0．01）,初始菌数的影响达到显著水平（P〈0．05）,氯化钠浓度的影响不显著（P〉0．05）。     

CHANGES OF CELL WALL COMPONENTS AND PAL ACTIVITY IN FRESH-CUT BAMBOO SHOOTS DURING COLD STORAGE

Changes of cell wall components in relation to softening and lignifying of fresh-cut bamboo shoots (Phyllostachys heterocycla var. pubescens) was investigated. Increased activity of phenylalanine ammonia-lyase (PAL) was related to a rise of lignin content in the basal section but not in the middle and apical sections. PAL activity was also associated with an increase in phenolic content in the middle section, but not in the basal and apical sections. The softening process occurred mainly in the apical section, while lignification took place primarily in the basal section. In the middle section, both softening and lignification also occurred but to a lesser extent.