葡萄糖苷转移酶生产菌种的筛选

用甲基葡萄糖及麦芽糖为底物,对５０多株黑曲霉α－葡萄糖苷酶活性作了测定,结果表明各菌株对这二类底物之水解能力并不一致,甲基葡萄糖水解活性高的,其麦芽糖水解能力未必也高。通过ＴＬＣ测定这些菌株生成异麦芽低聚糖之能力,结果表明甲基葡萄糖和麦芽糖为底物的水解能力并不能正常反映转苷反应的能力。酶活力高的,生成异麦芽低聚糖的能力未必比活性低的为强,造成上述结果的原因,或许是胞外酶中存在着仅有水解作用的α－葡     

Genetic and potential non-genetic benefits increase offspring fitness of polyandrous females in non-resource based mating system

Background  

The adaptive significance of female polyandry is currently under considerable debate. In non-resource based mating systems, indirect, i.e. genetic benefits have been proposed to be responsible for the fitness gain from polyandry. We studied the benefits of polyandry in the Arctic charr (Salvelinus alpinus) using an experimental design in which the material investments by the sires and maternal environmental effects were controlled.     

Interactive effects of elevated CO2 and drought stress on leaf water potential and growth in Caragana intermedia

We studied the responses of leaf water potential (Ψ_w), morphology, biomass accumulation and allocation, and canopy productivity index (CPI) to the combined effects of elevated CO₂ and drought stress in Caragana intermedia seedlings. Seedlings were grown at two CO₂ concentrations (350 and 700 μmol mol⁻¹) interacted with three water regimes (60–70%, 45–55%, and 30–40% of field capacity of soil). Elevated CO₂ significantly increased Ψ_w, decreased specific leaf area (SLA) and leaf area ratio (LAR) of drought-stressed seedlings, and increased tree height, basal diameter, shoot biomass, root biomass as well as total biomass under the all the three water regimes. Growth responses to elevated CO₂ were greater in well-watered seedlings than in drought-stressed seedlings. CPI was significantly increased by elevated CO₂, and the increase in CPI became stronger as the level of drought stress increased. There were significant interactions between elevated CO₂ and drought stress on leaf water potential, basal diameter, leaf area, and biomass accumulation. Our results suggest that elevated CO₂ may enhance drought avoidance and improved water relations, thus weakening the effect of drought stress on growth of C. intermedia seedings.     

歌德与生物学

歌德（Goethe）是德国古典文学和民族文学的杰出代表,也是世界文学史上最杰出的作家之一。青年时代,他的书信体小说《少年维特之烦恼》使他获得了巨大的成功;而他晚年的作品《浮士德》则是他一生丰富的思想总结和艺术探索的结晶,因而与荷马史诗、但丁的《神曲》和莎士比亚的《哈姆雷特》并列为欧洲文学的四大古典名著。歌德在世界文学史上的重要地位是毋庸置疑的,但是他在生物学上的重要贡献就鲜为人知了。     

生态教育对游憩冲击的影响

目前,如何使用生态教育这种柔性手段来减缓游憩冲击是旅游地生态管理领域的一个富有挑战力的议题.使用KAP干预技术(知识(K),意识(A)和行为(P))来测量和评价生态教育干预的成效.根据游客的不同出游方式,将实验对象分成团队组与散客组两类,并挑选了一批生态素质较高的环保志愿者作为固定组进行参照对比.调查分前后两次进行,每次运用统一的干预方法和一份基于国内游客的特点的KAP问卷对实验对象的知识、意识和行为进行干预和测量.测量结果显示,游客生态知识与旅游行为比较相关,表明游客通过干预,能把正确的生态观和旅游道德规范内化为个人的思想信念,进而又外显为品德行为,从而促进知、信、行的相互转化,实现游憩冲击管理目的.同时,教育干预后游客的生态知识、意识、行为有不同程度的提高和改善,干预前后知识之间、干预前后意识之间、干预前后行为之间以及干预前后知识、意识和行为之和之间有显著差异.因此,对游客开展生态教育干预具有实际意义和应用价值.     

“电子”cDNA文库筛选指导基因的全长cDNA克隆

“电子”ｃＤＮＡ库筛选主要是指通过采用生物信息学的方法延伸表达序列标签（ＥＳＴ）序列,以获得基因的部分及至全长ｃＤＮＡ序列,避免或部分避免构建与筛选ｃＤＮＡ库等烦琐的实验室工作。该方法具体体现了ＥＳＴ数据库的迅速扩张已导致识别与克隆新基因的策略发生革命性的变化。ＥＳＴ序列ＺＡ７３为本实验室克隆到的可能参与辐射致气管上皮细胞恶性转化过程的基因片段,本研究采用“电子”ｃＤＮＡ库筛选的方法对其可能     

磷缓解水鳖镉毒害的生理研究

研究了Cd对水鳖生理生化过程的影响及Pi对Cd胁迫的缓解作用。结果显示,Cd能抑制水鳖的代谢和生长,使叶绿素含量与光合速率下降,呼吸速率与可溶性糖含量增加,POD活性增强;当加入0.6mmol/L Pi后,能相对减轻Cd造成的毒害,表现出Pi对Cd的拮抗和缓解作用。