n型LEC-GaAs中E5能级的研究

于2010-11-23批量导入

石油芳烃污染生物标记

从辽河油田不同石油污染地区采集土样，查明石油污染类型影响微生物群落生态分布。分离筛选得到6株优势菲降解菌B1（假单胞菌属），B2（黄单胞菌属），E3（黄杆菌属），E4 (假单胞菌属），E5（微杆菌属），E6（黄杆菌属）。B2、E4, E6含有质粒，大小均在25Kb左右。初步确定菲降解功能是由质粒控制的。菌株降解菲的能力与无细胞粗提液含有的菲双加氧酶活力的高低呈正相关。随着环境中菲浓度的增加。，菲双加氧酶活力、分子量为46KDa的蛋白量、降解质粒含量均随之增加，RNA不仅整体含量在增加，而且分子量为0. 45Kb的条带增加显著。 从E4菌分离纯化菲双加氧酶。分子量约为46KDa,表观分子量为120KDa；酶活最适pH为7.0,最适温度是29 ℃，最稳定的pH是中性，在温度超过40℃时，酶稳定性明显下降；乙酸钠抑制酶活性；H_2O_2浓度为0.4%时，双加氧酶活力提高最大；纯酶只氧化菲，有很强的底物特异性；当菲的浓度增加到80uM时，酶促反应速率达到最大，米氏常数约为40uM；0.1mM菲咯琳对菲双加氧酶有明显的抑制作用；二价铁离子不仅可以提高酶活性而且对双加氧酶有明显的激活作用。

模拟增温对短穗兔耳草生长特征的影响

[目的]探讨短穗兔耳草个体对模拟增温的响应。[方法]采用国际冻原计划（ITEX）模拟增温对植物影响的研究方法,将温棚从小到大的顺序依次设为A、B、C、D、E5个温度梯度,分析不同温度梯度下短穗兔耳草个体生长特征的变化,研究模拟增温对短穗兔耳草生长特征的影响。[结果]随着温棚直径的减小,温度（地表温度和土壤温长）逐渐升高。与对照相比,A、B、C、D、E5个处理分别提高了2.68、1.57、1.20、1.07和0.69℃（地表气温）,1.74、1.06、0.80、0.60和0.30℃（土壤温度）。短穗兔耳草从对照至A温室随着温度的升高,叶片数、叶片高度逐渐增加,而匍匐茎逐渐减少。[结论]叶片数变化与温度（地表温度和地温）呈正相关关系,增温促进了短穗兔耳草的营养生长,抑制了它的克隆繁殖能力。

鸡胚吗啡用药对学习记忆和成瘾易感性的影响及其受体机制

Prenatal morphine exposure affects neural development of fetus by impairing learning and memory, and increasing susceptibility to morphine abuse. Because nervous systems have different developmental characteristics during different developmental stages, administration of morphine at different stages also has different effects on learning, memory, and susceptibility to morphine. Due to the precise developmental processes of neurotransmitter systems in chick embryo’s brain, and unique superiority of chick embryo model, the purpose of the present studies was to explore critical periods correlated to the memory impairment and the increasing susceptibility to morphine, via one-trial passive avoidance and conditioned place preference as behavior models. Then the possible roles of mu and delta opioid receptors as the possible mechanism were analyzed. Experiment 1 showed that injecting low dose of morphine (1 mg/kg) during the period embryonic 5 to 8 significantly impaired the function of learning and memory, worse than any other periods of the same treatment. Experiment 2 showed that injecting low dose of morphine during the period embryonic 17 to 20 significantly increased the susceptibility to morphine in the new-born chicks. The affected chicks acquired the morphine conditioned place preference more quickly, and maintained it much longer. Experiment 3 showed that during E5-8, injecting delta receptor antagonist naltrindole reversed the learning and memory impairment caused by morphine while delta receptor agonist DPDPE impaired learning and partial memory function. On the other hand, mu opioid receptors had little effect. As for E17-20, given naloxonazine can reverse the increases of susceptibility to morphine, and the mu receptor agonist DAGO cause the increases of susceptibility to morphine. Delta receptors have no effect. The above results demonstrated that prenatal morphine expousure at different developmental periods of chick embryo caused different influences on memory and susceptibility to morphine. That is, E5-8 is the critical period correlate to memory impairment; and E17-20 is the critical period correlate to susceptibility to morphine. Delta receptors were critical in learning and memory impairment while mu receptors in susceptibility.