油田次生盐渍化土对几种作物的影响

土壤盐渍化会严重影响作物生长发育及产量,在供试的3种作物中,油菜耐盐能力较差,棉花耐盐能力最强,大豆次之.在一定盐度范围内,作物某些生长性状和产量性状与土壤含盐量之间存在显著的哪相关关系.室内测试分析和田间调查表明:①油菜株高与土壤含盐量之间呈曲线相关,油菜单株结果数与土壤含盐量之间存在极显著的半对数线性相关关系;②大豆植株成活率与电导率EC25之间呈极显著的半对数线性负相关关系,其单株结荚数与EC25之间有极显著的线性负相关关系;③棉花成活率和土壤含盐量之间呈曲线相关,线型呈抛物线,棉花相对产量与土壤的含盐量呈线性负相关性.     

Effect of SAPK/JNK signal pathway on neuronal apoptosis in cerebral infarction rats

AIM: To investigate the molecular mechanism of neuronal apoptosis by observing the changes of key proteins in SAPK/JNK and Bcl-2/Bax signal pathways after brain infarction. METHODS: The cortical infarction was induced by photochemistry, namely photothrombotic cortical injury (PCI). Thirty-six Sprague-Dawley rats were randomly divided into 2 groups: PCI group and sham-operated group. The ipsilesional cortex was harvested for histomorphometry and transmission electron microscopy 7 days after PCI. Some key proteins including p-JNK1, p-JNK2, p-c-Jun, p-ATF-2, total JNK1, total JNK2, Bcl-2 and Bax were detected by Western blotting analysis.RESULTS: The cortical infarction in rats was successfully induced by photochemistry. The apoptosis of neurons in cortex was more obvious in PCI group than that in sham-operated group 7 days after PCI. The levels of p-JNK1, p-JNK2, p-c-Jun and p-ATF-2 in PCI group were significantly higher than those in sham-operated group, whereas the ratio of Bcl-2/Bax was significantly lower(P<0.05). CONCLUSION: Apoptosis is a major contributor to neuronal loss induced by cerebral hypoxia-ischemia for a long period after cortical infarction. The process is related to some apoptotic proteins such as Bcl-2/Bax and the SAPK/JNK signal pathways activated by ischemic injury.     

Isolation and characterization of a novel tannase from a metagenomic library

A novel gene (designated as tan410) encoding tannase was isolated from a cotton field metagenomic library by functional screening. Sequence analysis revealed that tan410 encoded a protein of 521 amino acids. SDS-PAGE and gel filtration chromatography analysis of purified tannase suggested that Tan410 was a monomeric enzyme with a molecular mass of 55 kDa. The optimum temperature and pH of Tan410 were 30 °C and 6.4. The activity was enhanced by addition of Ca(2+), Mg(2+) and Cd(2+). In addition, Tan410 was stable in the presence of 4 M NaCl. Chlorogenic acid, rosmarinic acid, ethyl ferulate, tannic acid, epicatechin gallate and epigallocathchin gallate were efficiently hydrolyzed by recombinant tannase. All of these excellent properties make Tan410 an interesting enzyme for biotechnological application.     

基于贝叶斯网络的水环境管理研究

贝叶斯网络是一种定性与定量分析相结合的不确定性推理方法,以图论的形式直观的表达了实例系统中变量间的不确定性关系,概率推理的结果能够使多个管理目标均达到最优.应用贝叶斯网络解决水环境管理中具有不确定性的多目标决策问题,通过对决策变量氮磷排放浓度的调控达到有效的改善水环境的目标.分析具体的水环境管理系统中变量间的相互关系,...     

沙洋县建设用地集约利用评价

随着我国工业化和城镇化迅速发展,以前我国建设用地粗放利用方式已不适应经济社会的发展,建设用地集约利用已经成为必然选择.文章以沙洋县为例,利用BP神经网络对其建设用地集约利用水平进行评价,通过分析其建设用地集约利用情况,评价其集约利用程度,然后根究沙洋县建设用地集约利用程度不高的特点,提出相关的对策和途径.     

秋茄KcRD22基因的克隆与功能分析

本文以用200mmol／LNaCl处理24h后的秋茄幼苗为材料提取秋茄叶片总RNA,利用RT-PCR方法克隆获得KcRD22基因的全长cDNA,通过构建pCAMBIA-2300-KcRD22过表达载体,利用农杆菌侵染的方式获得过表达KcRD22的烟草转基因株系,并对转基因株系的耐盐性做出初步分析。实验结果显示：KcRD22基因的ORF长1131bD,编码1个等电点为9．07、分子量为39．8kD、由375个氨基酸组成的蛋白。PCR及RT—PCR鉴定结果表明,KcRD22基因已经分别整合到8株烟草的染色体中,并在两个株系中获得表达。对转基因烟草进行光合作用测定,结果显示100mmol／LNaC1处理显著降低了野生型烟草的净光合速率,而转基因植株叶片的光合作用受到的影响较小。盐浓度达到200mmol／L时,转基因植株及野生型烟草净光合速率都明显降低,但盐胁迫解除后,转基因烟草光合作用的恢复情况明显好于野生型烟草,说明KcRD22的过表达提高了烟草的抗盐性。本文初步确定了KcRD22基因对植物耐盐性的贡献,这为进一步深入研究该基因在耐盐机制中的功能奠定了良好基础。     

药用真菌桑黄的抗氧化研究进展

从自由基清除能力,还原能力,亚铁离子的螯合能力,DNA损伤的抑制,MDA、SOD含量等方面对桑黄(Phellinus sp.)抗氧化研究进行概述;并展望其发展趋势.     

清原县农业机械化发展现状与对策

原县地处辽东山地丘陵区,发展农业机械化具有特殊性。综述清原县农业机械化发展现状,分析其存在的5个主要问题,包括农机装备水平不高、作业水平低、投入和扶持力度还有待继续加大、社会化服务功能不全和推广体系和队伍建设落后,并提出相应的解决对策。     

播种方式与追肥时期对黑龙江省冬小麦根系生长及产量的影响

为了探寻黑龙江省冬小麦适宜的播种方式和追肥时期,在田间条件下,研究了播种方式和追肥时期对冬小麦根系生长及产量的影响.结果表明,不同追肥处理下小麦的根冠比随生育期呈下降趋势;根系体积、根系表面积生长随生育期呈先升高后下降的变化趋势,乳熟期达到峰值;不同处理间产量呈现显著性差异,拔节期一次施肥垄沟播处理与平播处理分别比各自对照(不追肥处理)提高27.8％、39.7％,返青期施肥分别提高21.4％、21.1％,返青期与拔节期分施分别提高27.7％、26.7％.垄沟播种在拔节期一次追施氮肥产量可达到最高,比平播处理产量提高14％.黑龙江省冬小麦采取垄沟播种在拔节期适量追肥的栽培技术有助于根系生长及提高产量.     

黄山市对做好旅游城市动物卫生监督工作的探索

黄山市位于安徽省南部,境内旅游资源丰富,景观独特,以奇松、怪石、云海、温泉"四绝"著称于世,1985年,黄山作为唯一的山岳风光,被评选为全国十大风景名胜之一。2010年旅游接待量达到1001.3万