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71.
From the lichen Cladonia graciliformis, three new pigments A, B and C were isolated along with bellidiflorin. Pigment A was an epimer of (+)-rugulosin diacetate and pigment B and C its corresponding deacetylated derivatives. Bellidiflorin is probably an iron complex compound of A. The chemical constituents of the mycobionts of Cl. graciliformis and Cl. bellidiflora were also studied. 相似文献
72.
Sticticin has been isolated from the thallus of Lobaria laetevirens. Its structure was determined by spectroscopic methods (NMR, MS) and comparison with a synthetic sample. It has been found in several species of the Stictaceae. 相似文献
73.
The structures of two new aliphatic acids, isomuronic and neuropogolic acid, from the lichen Neuropogon trachycarpus, were established by spectroscopic (MS, 1H and 13C NMR) and chemical evidence. Circular dichroism data allowed the configuration of isomuronic acid to be assigned as 2R. 相似文献
74.
DOPA betaine, tyrosine betaine and N-dimethyltyrosine were isolated from the lichen Lobaria laetevirens. Their structures were determined by ra 相似文献
75.
The mycobiont, Xanthoria parietina, and the phycobiont, Trebouxia decolorans, of the lichen X. parietina have been cultured separately and their sterols analysed. X. parietina contained ergosterol and lichesterol as the major constituents together with lower levels of three other C28 sterols. Culture of the mycobiont in the presence of [CD3]-methionine resulted in the incorporation of two deuterium atoms into the C-24 methyl group of these sterols demonstrating that a 24-methylene intermediate was produced as occurs in other fungi. The phycobiont, T. decolorans contained predominantly poriferasterol with lower levels of clionasterol, ergost-5-en-3β-ol, brassicasterol and cholesterol. Two other Trebouxia spp. (213/3 and 219/2) contained similar sterol mixtures. 相似文献
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77.
Sophie J. McCoy 《Journal of phycology》2013,49(5):830-837
As the process of ocean acidification alters seawater carbon chemistry, physiological processes such as skeletal accretion are expected to become more difficult for calcifying organisms. The crustose coralline red algae (Corallinales, Rhodophyta) form an important guild of calcifying primary producers in the temperate Northeast Pacific. The morphology of important ecological traits, namely, skeletal density and thallus thickness near the growing edge, was evaluated in Pseudolithophyllum muricatum (Foslie) Steneck & R.T. Paine, the competitively dominant alga within this guild. P. muricatum shows a morphological response to increased ocean acidification in the temperate Northeast Pacific. Comparing historical (1981–1997) and modern (2012) samples from the field, crust thickness near the growing edge was approximately half as thick in modern samples compared with historical samples, while crust calcite density showed no significant change between the two sample groups. Morphological changes at the growing edge have important consequences for mediating competitive interactions within this guild of algae, and may affect the role of crustose coralline algal beds as hosts to infaunal communities and facilitators of recruitment in many invertebrate and macroalgal species. 相似文献
78.
摘要 目的:研究口腔扁平苔藓(OLP)患者血清白介素-17(IL-17)、P物质(SP)、趋化素(Chemerin)水平与疾病活动和免疫功能的关系。方法:选取我院2019年3月~2021年5月期间收治的117例OLP患者作为观察组,其中非糜烂型69例,糜烂型48例。另选取同期来我院体检的健康志愿者60例为对照组。对比对照组及不同分型患者血清SP、IL-17、Chemerin水平,对比不同分型患者的疾病活动相关评分和免疫功能指标,应用Pearson相关分析血清SP、IL-17、Chemerin水平与疾病活动相关评分和免疫功能指标的相关性。结果:不同分型OLP患者血清SP、IL-17、Chemerin水平均高于对照组(P<0.05),且糜烂型OLP患者的血清SP、IL-17、Chemerin水平高于非糜烂型OLP患者(P<0.05)。糜烂型OLP患者的CD3+、CD4+低于非糜烂型OLP患者(P<0.05),糜烂型OLP患者的CD8+、免疫球蛋白M(IgM)水平、OLP网纹-糜烂-溃疡疾病活动积分(REU)总分高于非糜烂型OLP患者(P<0.05)。糜烂型与非糜烂型OLP患者间免疫球蛋白A(IgA)、免疫球蛋白G(IgG)水平对比差异无统计学意义(P>0.05)。Pearson相关性分析结果显示,血清SP、IL-17、Chemerin水平与IgM水平、REU总分均呈正相关(P<0.05)。结论:OLP患者血清IL-17、SP、Chemerin水平异常升高,三者共同参与了OLP患者的病情进展及免疫功能调节。 相似文献
79.
东北大小兴安岭地区是中国地衣的重要分布地之一, 蕴藏着丰富的地衣生物多样性。本研究基于259份标本馆馆藏及采集自东北大小兴安岭31个保护区的新鲜地衣标本, 结合形态学、解剖学、化学和DNA片段的综合分析, 鉴定并报道了该地区梅衣科岛衣类和袋衣类地衣11属31种, 包括环北极成分13种, 东亚成分11种, 世界广布成分3种, 中国特有成分3种, 欧亚成分1种。与之前记录和报道的该地区同类地衣物种组成进行对比, 结果显示隶属于2属的6种地衣在该地区未被重新发现, 表明这些地衣在该地区的分布可能大大萎缩乃至消失, 尤其是属于东亚成分的袋衣属2种: 粉袋衣(Hypogymnia farinacea)和日光山袋衣(H. nikkoensis), 自最初以东北大小兴安岭标本为凭证在中国报道分布后, 30余年未再新增任何标本信息, 日光山袋衣在近期中国大型真菌红色名录评估中被推测处于易危状态。 相似文献
80.