Effect of poly(ADP-ribose) polymerase on the response of guinea pig tracheas induced by peroxynitrite in vitro

AIM and METHODS: to elucidater the effect of poly(ADP-ribose) polymerase(PARP) on tracheal hyperreactivity of guinea - pig induced by peroxynitrite, the responses of guinea pig tracheas to histamine af- ter incubation with peroxynitrite in the absence and presence of 3 - aminobenzamide(3 - AB), a highly selective inhibitor for PARP, were observed in vitro. RESULTS: The exposure of tracheal strips to peroxynitrite led to epithelial damage and hyperreacitivity to histamine, both of which were reversed by 3 - AB(lmmol/L or 5mmol/L), whereas incubation of tracheal strips with 3 - AB(5mmol/L) had no effect on the reponses. CONCLUSION: PARP is involved in the epithelial damage and hyperreactivity of guinea - pig tracheas induced by peroxynitrite. The results suggested that inhibition of excessive activation of PARP may represent a novel strategy for the prevention and therapy of airway hyperreactivity in asthma.     

Effects of EBV infection on growth and apoptosis of nasopharyngeal carcinoma cell line

AIM: To explore the effect of EBV infection on growth and apoptosis of nasopharyngeal carcinoma(NPC) cell line.METHODS: NPC cell line CNE1 was directly infected by Epstein Barr virus (EBV). The expression of EBV-latent membrane protein 1 (EBV-LMP1) and bcl-2 were detected by immunohistochemistry method (LSAB). The growth of NPC cells was identified by MTT method. Apoptotic carcinoma cells were detected by flow cytometry analysis and the terminal deoxynucletidyl transferase-medicated dUTP-biotin nick end labeling (TUNEL) methods. RESULTS: EBV-LMP1 was positive in CNE1 infected by EBV(E-CNE1). Compared with CEN1, the growth of E-CNE1 apparently increased (P＜0.01). No apoptotic carcinoma cells were detected and bcl-2 postive cells were 2%~3% respectively in 2 kinds of NPC cells.CONCLUSION: Growth of NPC cells is enhanced by EBV infection and EBV-LMP1 expression, but no influence on expression of bcl-2 and apoptosis of NPC cells.     

Rapamycin promotes repair of neurovascular units after ischemic stroke

Neurovascular unit （NVU） is composed of neurons, endothelial cells, pericytes, astrocytes, macrophages/microglia, smooth muscle cells, extracellular matrix, etc, and plays vital roles in maintenance of the normal brain tissue function and cellular homeostasis. Cerebral ischemia caused by stroke can harm various components of NVU. Repairing damaged NVU and maintaining its structural and functional integrity are an effective way to improve stroke treatment. Resent research has found that rapamycin not only enhances autophagy of neurons but also effectively repairs the injuried components of NVU , thereby reducing neural damage after stroke. In this paper, the mechanisms of rapamycin underlying the repair of injured NVU after ischemic stroke is reviewed to provide guidance for its application in the treatment of stroke.     

大兴安岭北部的灰化土

大兴安岭北部,即伊勒呼里山以北的大兴安岭主体部分,大致位于北纬51°20'—53°28',东经121°31'—126°30'之间,是我国的最北端。其地带性土壤类型,过去说法不一,曾有人命名为生草灰化土¹⁾、棕色灰化土、棕色泰加林土²⁾、灰白色森林土(中国科学院内蒙古宁夏综合考察队等,1978)、棕色针叶林土³⁾、漂灰土(中国科学院南京土壤研究所主编,1978)等。     

不结球白菜维生素C和可溶性糖含量的遗传分析

采用主基因—多基因混合遗传模型分析方法,对不结球白菜乌塌菜×矮脚黄、雪克青×矮脚黄两个组合的维生素Ｃ、可溶性糖含量进行单世代和联合世代遗传分析。结果表明,两组合中维生素Ｃ含量遗传符合一个主基因和多基因的混合遗传模型,主基因遗传率为５２６８％～７４１２％。可溶性糖在雪克青×矮脚黄组合中也符合主基因—多基因遗传模型,主基因遗传率为８９７３％～８９７９％。维生素Ｃ和可溶性糖主基因效应均以加性效应为主,在乌塌菜×矮脚黄组合中,两性状主基因有较明显的负向显性效应,在雪克青×矮脚黄组合中,显性效应不明显。育种实践中应注重对主基因加性效应的利用。     

我国桃树设施栽培的现状、存在问题及对策

总结了我国桃树设施栽培的现状,包括设施栽培的目的、主要形式、品种选择、环境要求、调控技术和主要栽培技术等,指出了生产上存在的问题并提出了相应的对策     

我国棉花纤维品质现状分析

2001~2005年农业部对我国主产棉省主栽棉花品种纤维的抽查结果表明:纤维长度主要分布在28~29mm;纤维整齐度指数高,主要分布在82%~84%;断裂比强度处于中等偏上水平,主要分布在27~29 cN/tex;纤维成熟较好,粗细适中,马克隆值主要分布在4.6左右;色特征级多数分布在21、31、41级。目前我国棉花纤维质量可以满足纺织工业纺中、低档棉纱(32~40支纱)的要求,可纺高支纱(60~80支)的原棉纤维所占比例较少。     

土地利用总体规划中生态退耕规划标准指标体系构建与应用

生态退耕规划标准是新一轮土地利用总体规划编制过程中确定生态退耕布局和规模的准则和依据。针对目前生态退耕规划仅从改善生态环境的单一目标出发,而忽视生态退耕对区域粮食安全、经济发展影响的情况,该文以河北省为例,根据整体性、综合协调、科学和可操作性的原则,构建了生态退耕规划标准指标体系;并以河北省下辖11个行政市为评价单元,应用层次分析法进行河北省生态退耕区域评价;应用最小人均耕地面积的概念,确定生态退耕规模。根据评价单元各因素和综合得分情况,河北省可划分为重点、次重点和一般生态退耕区。预计到2020年河北省生态退耕总规模约为61.09×10⁴ hm²。     

深松旋耕组合作业机的研制与试验研究

根据国内中等功率拖拉机配套农机具的研究现状,以机组匹配理论为依据,研制了与中型拖拉机配套的深松旋耕组合作业机,并进行了单独深松、单独旋耕和组合工况的试验。试验表明所研制的机具在作业时能充分发挥拖拉机的动力性,减少拖拉机的功率消耗。机具配置的深松铲和旋耕刀片排列合理,深松扰动影响宽度和旋耕宽度相匹配,作业时波动范围较小,偏牵矩对拖拉机方向的稳定性基本没有影响。机具的研制也为与大功率拖拉机配套新型农机具的开发提供了借鉴。     

近红外光谱分析法测定菜籽油中芥酸的含量

采用多通道PDA型近红外光谱仪,应用偏最小二乘法建立了菜籽油中芥酸含量与近红外透射光谱的校正模型,讨论多项式求导及平滑的窗口宽度和相关系数法筛选有效波长对校正模型的影响,并对10个预测集样品利用预测相关系数R_p和预测均方根误差RMSEP指标进行了预测精度分析,结果发现：在使用全谱数据进行偏最小二乘回归建模时,一阶7点求导及平滑的预处理方法结果最佳,此时建模效果为：R_p=0.739,RMSEP=1.659;在此基础上通过相关系数法筛选波长后的建模效果为：R_p=0.958,RMSEP=0.963。后者R_p提高29%,RMSEP减少42%。由此可得出多项式求导及平滑法和相关系数法相结合对校正模型稳健性,预测精度都有较大提高的结论。研究证明：多通道近红外光谱仪快速测测菜籽油中芥酸含量的方法是可行的。