甲醛胁迫对3种室内观赏植物的生理生化影响

采用盆栽试验研究了甲醛胁迫后黄常山、短梗大参和袖珍椰子3种室内观赏植物叶片的生理生化指标变化,结果表明:甲醛胁迫后3种植物的生理生化指标与对照相比均有不同程度的变化。当甲醛浓度达到最高值288mg/m3时,与对照相比,黄常山叶片质膜相对透性升高64%,MDA含量升高178%,叶绿素含量降低51%,SOD与POD活性分别降低26%和55%;短梗大参叶片质膜相对透性升高10%,MDA含量升高19%,叶绿素含量降低43%,SOD与POD活性分别降低24%和25%;袖珍椰子叶片质膜相对透性升高9%,MDA含量降低24%,叶绿素含量降低30%,SOD与POD活性分别增加41%和36%。以生理生化指标的变化为基础,采用隶属函数法对3种植物的甲醛抗性进行综合评判,其抗性由强至弱为:袖珍椰子>短梗大参>黄常山。     

镉对土壤秀丽隐杆线虫的毒性效应

为明确镉(Cd)对土壤无脊椎动物线虫的毒性效应及不同类型土壤中Cd的毒性差异,以生长量、生育率和繁殖量为评价终点,研究江西鹰潭红壤、江苏苏州水稻土、吉林长春黑土3种土壤中外源Cd对模式生物——秀丽隐杆线虫(Caenorhabditis elegans)的毒性效应。结果表明：以3种土壤总Cd含量推导出的Cd对秀丽隐杆线虫的生长毒性的EC₅₀(半数效应浓度)分别为54.37、197.54mg·kg^-1和287.02 mg·kg^-1,对生育毒性的EC₅₀分别为7.07、77.41 mg·kg^-1和103.09 mg·kg^-1,对繁殖毒性的EC₅₀分别为5.75、13.84 mg·kg^-1和85.94 mg·kg^-1。通过毒性阈值可知,线虫的评价终点对Cd毒性的敏感性由高到低分别为繁殖、生育、生长。相关性分析表明,土壤pH、阳离子交换量、有机质、碳酸钙和锰氧化物含量是影响土壤中Cd毒性的主要因素。基...     

地衣对重金属的累积效应用于乌鲁木齐市大气监测的研究

[目的]评价地衣重金属富集能力及其在城市空气环境质量评价中的应用前景.[方法]利用地衣移植法把丽石黄衣移植到乌鲁木齐市区15个监测点,用原子吸收光谱仪测量地衣体内6种重金属含量,根据重金属含量计算单项污染量指数和Nemerow综合污染指数.[结果]随着移植时间的延长地衣体内的重金属含量出现上升趋势,丽石黄衣体内重金属含量具有显著的时空变化特征.同时把单向污染量指数作为变量进行聚类分析和主成分分析,显示15个监测点分为轻污染区、中度污染区、重污染区,严重污染区等三个等级.[结论]地衣具有较高的重金属富集能力,对大气污染较敏感,可以作为大气环境质量评价指示地衣种类.     

60Co-γ射线对2种花卉叶绿素及类胡萝卜素含量的影响

研究了60Coγ射线辐射袖珍椰子、帝王星对其植株叶绿素及类胡萝卜素含量的影响。结果表明:经不同剂量辐射处理后的袖珍椰子叶绿素和类胡萝卜素含量变化方向不一致,叶绿素a与叶绿素b呈显著正相关;20Gy辐射处理后的帝王星叶绿素及类胡萝卜素含量较高,叶绿素a、b和类胡萝卜素呈显著正相关。     

土壤中镉、铅对百日草种子萌发及生长的影响

研究了土壤中镉、铅对百日草种子萌发及对植株生长的影响。结果表明:随着土壤中含Cd、Pb浓度的增大,对种子的萌发均会起到抑制作用,同时随着重金属浓度的增加,植株体内的叶绿素含量、丙二醛含量也有明显的下降趋势。在Cd浓度为100 mg/kg时,百日草体内Cd的含量最高;在Pb浓度为1 000 mg/kg时,植株吸收Pb的含量最高。     

Cypermethrin-induced alterations in vital physiological parameters and oxidative balance in Caenorhabditis elegans

Cypermethrin belongs to the class of synthetic pyrethroids, which are being widely used as an insecticides in agricultural practices. The toxicity of cypermethrin is well studied in Drosophila melanogaster, fish, rats, mice, and is reported to cause neurotoxicity and oxidative stress during its metabolism. In this study, we evaluated the biological consequences of 4 h exposure to cypermethrin at sublethal concentrations (1, 5 and 15 mM) in Caenorhabditis elegans on physiological parameters such as egg laying, brood size, feeding and lifespan and oxidative stress parameters such as ROS, hydrogen peroxide levels, protein carbonyl, enzymatic antioxidants and glutathione levels. There was a significant and dose-dependent decrease in brood size (18-53%), egg laying (54-67%), feeding (29-58%) and marked decrease in lifespan (20%) at 15 mM of cypermethrin. Increase in levels of oxidative markers such as ROS (21-56%), intracellular hydrogen peroxide (17-62%), protein carbonyl (8-29%) and alteration in the activity of enzymatic antioxidants as well as depletion of glutathione (13-38%) were also observed. Our study offers evidence to show that cypermethrin induces significant oxidative stress in C. elegans and alters several physiological parameters in these worms, which can lead to impaired functioning, and survival of these worms.     

钩吻醇提物对兔离体肠肌的舒张作用及其机制

采用BL–420E生物机能实验系统,观察钩吻醇提物对兔离体肠肌自主收缩及对工具药乙酰胆碱(Ach)、BaCl2和组胺(HA)所致痉挛性收缩的影响,并探讨肌浆网Ryanodine受体阻断剂钌红(RR)、三磷酸肌醇(IP3)受体阻断剂肝素钠(HP)和一氧化氮合酶抑制剂左旋硝基精氨酸甲酯(L–NAME)对钩吻醇提物作用的影响。结果表明:终质量浓度0.16～0.64 mg/mL钩吻醇提物可剂量依赖性抑制离体肠肌自主收缩频率和张力;终质量浓度0.32 mg/mL钩吻醇提物对BaCl_2、HA诱导的离体肠肌收缩频率和张力具有显著抑制作用(P0.05),对Ach诱导的离体肠肌的收缩频率具有显著抑制作用(P0.05),对张力有极显著抑制作用(P0.01);RR、HP和L–NAME对经钩吻醇提物预处理的离体肠肌的收缩频率和张力分别表现为无影响、显著增强和显著拮抗(P0.05)。     

Settlement of larval top shell <Emphasis Type="Italic">Turbo (Batillus) cornutus</Emphasis> in response to several marine algae

ABSTRACT:     The settlement of larval top shell Turbo  ( Batillus )  cornutus in response to seven macroalgal and three benthic diatom species was examined in the laboratory. The percentages of larval settlement differed significantly among algal species, and were significantly higher on two red algal species ( Marginisporum crassissima , an articulated coralline alga, and Gelidium elegans , an agarophyte) than on the green algae, brown algae and benthic diatoms tested. Marginisporum crassissima induced larval settlement most strongly throughout the experiments. The percentage of larval settlement on a crustose coralline alga (unidentified species), which is known as a suitable substratum for abalone larvae, was much lower than on M. crassissima and G. elegans , which have morphologically complex growth forms . The percentage of settled individuals on ethanol-killed M. crassissima was much lower than on intact M. crassissima . The results indicate that physical structure is unlikely to be the main inducer of settlement; therefore, settlement of top shell larvae seems to be strongly induced by chemicals from the two red algal species. The specific distribution of juvenile top shell in the field may be at least partly determined by the strong induction of larval settlement by articulated coralline and gelidiacean algae.     

石斛多糖对延缓秀丽隐杆线虫衰老作用的影响

石斛是中国传统中药材,其多糖含量丰富,具有提高免疫力、抗氧化、延缓衰老等多种功效。本文以多糖含量丰富的铁皮石斛、细茎石斛和鼓槌石斛为对象,探讨了石斛多糖对模式生物秀丽隐杆线虫寿命、产卵量、运动行为能力、热应激能力等的影响。结果表明：三种石斛多糖在不影响秀丽隐杆线虫正常生殖能力的条件下显著延长线虫的平均寿命和最长寿命,其中80mg/L的细茎石斛多糖与对照组相比,平均寿命提高了33.2%;不同浓度的石斛多糖能明显提升线虫的运动能力,其头部摆动频率、身体弯曲频率、热应激能力均随着多糖浓度的升高而增加,与延长线虫寿命正相关。论文结果为阐述石斛多糖延缓衰老功能的作用机理,更好地开发利用石斛提供理论依据。