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141.
九头狮子草化学成分的研究 总被引:3,自引:0,他引:3
从九头狮子草种分离得到9个化合物,分别鉴定为:正十八烷(1)、cholest-5-en-3β-oxyl hexadecanoate(2)、硬脂酸(3)、软脂酸(4)、三十三烷醇(5)、β-谷甾醇(6)β-谷甾醇和豆甾醇的混合物(7)、β-谷甾醇和豆甾醇的葡萄糖苷(8)、尿囊素(9).其中化合物1~5系首次从本植物中分得. 相似文献
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143.
【背景】磷是引起水体富营养化的主要营养物质。生物除磷具有成本低、效率高且适用范围广等特点,成为近年来水处理研究领域的热点。目前虽然有一些聚磷菌被筛选获得,但它们的除磷效率不高,其除磷条件尚需优化。聚磷菌的固定化及回收利用也亟待研究。【目的】分离筛选并鉴定高效聚磷菌株,优化除磷环境条件,研究吸附材料对所筛菌株除磷的影响,为聚磷菌的开发利用提供理论依据。【方法】采用常规细菌分离筛选方法获得高效菌株,通过形态特征观察、生理生化实验和16S rRNA基因序列分析对菌株进行鉴定;结合单因素试验、Box-BehnkenDesign和响应面分析优化除磷条件;通过测定海绵、无纺布和聚氨酯泡沫对聚磷菌的吸附作用评估该材料的固定化效果。【结果】从连云港市某磷矿厂废水中分离筛选出一株高效聚磷细菌P49,经鉴定为解淀粉芽孢杆菌(Bacillus amyloliquefaciens);优化后的最佳除磷条件为pH 6.8、温度31℃、装液量30.2%,在此条件下P49除磷率可达80.43%;应用聚氨酯泡沫的吸附效果优于海绵和无纺布。【结论】解淀粉芽孢杆菌P49具有良好的除磷效果,可为生物除磷提供微生物资源,用聚氨酯泡沫吸附可实现对该菌株的固定化和回收利用。 相似文献
144.
Several studies have indicated that olfactory responses are impeded by
amiloride. Therefore, it was of interest to see whether, and if so which,
olfactory epithelial cellular compartments have amiloride- sensitive
structures. Using ultrastructural methods that involved rapid freezing,
freeze-substitution and low temperature embedding of olfactory epithelia,
this study shows that, in the rat, this tissue is immunoreactive to
antibodies against amiloride sensitive Na(+)- channels. However, microvilli
of olfactory supporting cells, as opposed to receptor cilia, contained most
of the immunoreactive sites. Apices from which the microvilli sprout and
receptor cell dendritic knobs had much less if any of the
amiloride-antibody binding sites. Using a direct ligand-binding
cytochemical method, this study also confirms earlier ones that showed that
olfactory receptor cell cilia have Na+, K(+)-ATPase. It is proposed that
supporting cell microvilli and the receptor cilia themselves have
mechanisms, different but likely complementary, that participate in
regulating the salt concentration around the receptor cell cilia. In this
way, both structures help to provide the ambient mucous environment for
receptor cells to function properly. This regulation of the salt
concentration of an ambient fluid environment is a function that the
olfactory epithelium shares with cells of transporting epithelia, such as
those of kidney.
相似文献
145.
S. DZIEMIAN J. MICHALIK B. PI ŁACIŃSKA S. BIALIK B. SIKORA R. ZWOLAK 《Medical and veterinary entomology》2014,28(4):465-469
Infestation by the nest‐dwelling Ixodes hexagonus Leach and the exophilic Ixodes ricinus (Linnaeus) (Ixodida: Ixodidae) on the Northern white‐breasted hedgehog, Erinaceus roumanicus (Erinaceomorpha: Erinaceidae), was investigated during a 4‐year study in residential areas of the city of Poznań, west‐central Poland. Of 341 hedgehogs, 303 (88.9%) hosted 10 061 Ixodes spp. ticks encompassing all parasitic life stages (larvae, nymphs, females). Ixodes hexagonus accounted for 73% and I. ricinus for 27% of the collected ticks. Male hedgehogs carried significantly higher tick burdens than females. Analyses of seasonal prevalence and abundance of I. hexagonus revealed relatively stable levels of infestation of all parasitic stages, with a modest summer peak in tick abundance noted only on male hosts. By contrast, I. ricinus females and nymphs peaked in spring and declined steadily thereafter in summer and autumn, whereas the less abundant larvae peaked in summer. This is the first longterm study to evaluate the seasonal dynamics of both tick species on populations of wild hedgehogs inhabiting urban residential areas. 相似文献
146.
147.
Kalliopi Stara Lavrentis Sidiropoulos Rigas Tsiakiris 《Human ecology: an interdisciplinary journal》2016,44(6):751-764
Vultures and eagles are large and impressive raptors that have a special role in the symbolic lore of local communities worldwide. We examine species folk names, everyday aphorisms, place names, local stories, ceremonies and folklore in modern Greece to demonstrate ways local communities conceptualize emblematic raptor species. As populations of these species are reduced or become extinct, local knowledge about them also disappears. On the other hand, conservation campaigns are mainly restricted on vultures’ sanitary services and ecotourism potential, often overlooking intangible values that are more stable and deeply rooted in local culture. Traditional ecological knowledge, local values and perspectives should be incorporated in reconstructing raptor public awareness profiles by modern conservation science for effective participatory conservation policy for these endangered species worldwide. 相似文献
148.
Predatory effect of Coccinella septempunctata on Thrips tabaci and Trialeurodes vaporariorum 总被引:1,自引:0,他引:1
P. N. Deligeorgidis C. G. Ipsilandis M. Vaiopoulou G. Kaltsoudas G. Sidiropoulos 《Journal of Applied Entomology》2005,129(5):246-249
Abstract: The predatory effect of adult ladybird Coccinella septempunctata L. on adults of thrips, Thrips tabaci Lindeman, and whiteflies, Trialeurodes vaporariorum (Westwood), was examined in controlled environment chambers, on tomato leaves, in transparent small plastic cages at proportions of 1/(10 + 10), 1/(20 + 20), 1/(30 + 30) and 1/(40 + 40) predator/number of thrips and whiteflies. We conclude that C. septempunctata could be used with success for the biological control of thrips and whiteflies in greenhouse crops, with almost the same effectiveness as for aphids, at predator/prey proportions near 1 : 30. Additionally, it was found a prey preference for T. tabaci in comparison with T. vaporariorum . According to the model used, effective predation is correlated with predator/prey ratio rather than to prey preference. 相似文献