盐藻尿苷二磷酸葡萄糖脱氢酶(DsUGD)基因的功能预测

盐生杜氏藻（Dunaliella salina）具有极强的耐盐性，藻体含有大量的胡萝卜素、蛋白质以及多糖类化合物．目前，已有研究报道指出蓝藻多糖是其适应高盐、高碱等环境的重要因素；而盐藻多糖的作用尚未见相关研究．尿苷二磷酸葡萄糖脱氢酶（UDP-glucose dehydrogenase，UGD，EC1．1．1．22）是多糖合成中的一个关键酶，它催化产生的UDP-葡萄糖醛酸是多糖合成中的关键前体物质．在微生物中，该酶参与到荚膜多糖的合成，是其致病性原因所在；在高等植物中，UGD参与到半纤维素的合成，与植物细胞壁形成密切相关．盐生杜氏藻是一类低等光合植物，它没有细胞壁和荚膜，因此关于UGD在该物种中的作用有待进一步研究．     

东营凹陷烃源岩低温催化酯水解生烃动力学研究

选用十八烷酸甲酯为模型化合物，以东营凹陷沙三和沙四烃源岩为载体，采用动力学方法考察了盐度、pH值、温度和压力对脂肪酸酯水解生烃反应的影响，求得了反应动力学参数。结果表明，烃源岩对脂肪酸酯水解生烃反应具有催化作用，与沙四烃源岩相比。沙三烃源岩作用下酯的水解反应恬化能要大，这与烃源岩中的粘土含量有关。     

Obtained transgenic wheat expressing pac1 mediated by Agrobacterium is resistant against Barley yellow dwarf virus-GPV

In fission yeast （Schizosaccharomyces pombe）, pacl gene was cloned with 99.3% nucleotide sequence similarity with published pacl in GenBank. In pET-5α expression system, the expression product of cloned pacl in E. coil showed activity to degrade the double-strand RNA. Harboring the binary vector pBI121, which contains pacl gene, Agrobacterium tumefaciens strain LBA4404 was used to transform the wheat immature embryos precultured 7-10 d. After preregeneration, regeneration and selection culture stage, totally 41 G418 resistant plants were obtained, in which 25 lines were proved to integrate with transgene and express transgene normally by PCR, Dot blot, RT-PCR and ELISA detection. Antivirus test carried out on 25 positive lines with high dose of Barley yellow dwarf virus-GPV revealed that 12 lines had resistance to BVDV-GPV in low level, another 12 lines had resistance to BVDV- GPV in middle level, and 1 line showed resistance to BVDV-GPV in high level. However, both low and middle level of resistance plants showed no symptoms when infected by viruses at low dose, which suggested the dose-dependent effect of the resistance mediated by pacl to BYDV-GPV.     

Responses of ephemeral plant germination and growth to water and heat conditions in the southern part of Gurbantunggut Desert

Ephemeral plants in the southern part of Gurbantunggut Desert were systematically monitored from 2002 to 2004 and the meteorological data and soil moisture during the same period were analyzed. The results show that the ephemeral plants germination and growth are sensitive to the changes of water and heat condition. The time for daily temperature over 0℃ in early spring in 2003 was delayed nearly 10 d compared with that in 2002, while the soil water changed little in the same period. Observation showed that there were 28 ephemeral species germinated in 2002, their life period was about 70 d in spring, and the maximum cover of ephemeral synusia reached 46.4%. However, only 17 ephemeral species germinated in 2003, their life period was about 50 d in spring, and their maximum cover was only 20.8%. The height of ephemeral plants was significantly higher in 2002 than that in 2003. It can be seen that ephemeral plant germination and growth in spring are strongly dependent on temperature. The changes of water conditions can affect ephemerals germination and growth as well. Because no heavy precipitation occurred during summer in 2002, only a few ephemerophytes were observed in autumn after ephemerals completed their life circle in early spring. However, about 60 mm precipitation was recorded from July to August both in 2003 and in 2004. Some ephemerals such as Erodium oxyrrhynchum and Carex physodes, etc. covered the dune surface rapidly with a cover 〉10%. Therefore, the ephemerals not only germinate in autumn after the early spring, some species may germinate in summer if adequate rainfall occurs. The study on responses of ephemerals growth to water and heat conditions not only has a certain ecological significance but also contributes a better understanding to the effect of climate changes on the desert surface stability.     

Diversity of arbuscular mycorrhizal fungi associated with desert ephemerals growing under and beyond the canopies of Tamarisk shrubs

The arbuscular mycorrhizal （AM） fungal status of the four most common ephemeral plant species, Chorispora tenella （Pall.） DC., Ceratocephalus testiculatus （Crantz） Bess., Eremopyrum orientale （L.） Jaub et. Spash and Veronica campyIopoda Boiss growing in an area dominated by Tamarisk shrubs （Tamarix spp.） was investigated. Samples of the four ephemerals and their rhizosphere soils were collected from underneath and beyond the canopies of the Tamarisk shrubs. Plant mycorrhizal status and soil AM fungal spore densities and community structures were analyzed and compared under and beyond the shrub canopies. The mycorrhizal colonization rates of the ephemerals and spore densities in their corresponding rhizosphere soils were significantly lower under the shrub canopies than beyond. The number of AM fungal species under the shrubs （12） was also lower than beyond the canopies （19）. When soil properties in the rhizospheres of the four ephemerals were examined, available N and P and total P, organic matter content, total salt content and electrical conductivity （EC） were all higher under the canopies than beyond. In contrast, soil available K and pH showed no such trend. A total of 21 AM fungal species were isolated from rhizosphere soils of the four ephemerals. Five belonged to Acaulospora, one to Archaeospora, thirteen to Glomus and two to Paraglomus. We conclude that the canopies of Tamarix spp. exerted some influence on the AM status of the ephemerals and on the AM fungal communities and some of the properties of their rhizosphere soils.     

重视数学史在高职数学教学中的作用

在师范类高职院校中结合数学史进行数学教学,可以激发学生的学习兴趣和动机;可以培养学生的创新意识和严谨求实的学习态度;可以让学生感受数学的魅力;可以进行德育渗透,增强民族自豪感。     

清肠产品大搜索

万松堂肠清茶，北京御生堂肠清茶，欣方冲剂，回春花便秘茶，碧生源常润茶。     

中国社会科学院《中国少数民族文学研究资料库》一期成果结项

2006年3月31日，中国社会科学院民族文学研究所举行院重大课题《中国少数民族文学研究资料库》结项报告会暨鉴定会。江蓝生副院长在会议期间参观了《中国少数民族文学研究资料库》的各项成果。并对民文所所取得的成果予以高度评价。     

植物水势系数及其应用实例

本文提出了植物水势系数的概念与计测公式，即植物水势系数是植物水势占大气水势和土壤水势对植物水势产生直接影响力那部分水势之和的比值。并对在塔克拉玛干沙漠生长的沙生柽柳进行了应用实例的验证。结果表明，在自然状态下，植物水势系数可作为衡量植物对环境胁迫反应强弱的一个指标。