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51.
本研究以松萝属为研究对象,构建了该属核糖体5.8S和第二转录区间(ITS2)的二级结构模型,并对种间的结构差异进行了比较。结果显示,松萝属的结构与先前发表的真核生物ITS2二级结构模型非常相似。属内种间的结构差异主要集中在第二转录区间的臂上。核酸序列分析所产生的系统树与结构特征的比较结果相一致,表明ITS2的二级结构信息可以作为一种辅助的分类手段,适用于松萝属的种的鉴定和亲缘关系研究。 相似文献
52.
Vianney Denis Takuma Mezaki Kouki Tanaka Chao-Yang Kuo Stéphane De Palmas Shashank Keshavmurthy Chaolun Allen Chen 《PloS one》2013,8(1)
Background
Seawater temperature is the main factor restricting shallow-water zooxanthellate coral reefs to low latitudes. As temperatures increase, coral species and perhaps reefs may move into higher-latitude waters, increasing the chances of coral reef ecosystems surviving despite global warming. However, there is a growing need to understand the structure of these high-latitude coral communities in order to analyze their future dynamics and to detect any potential changes.Methodology/Principal Findings
The high-latitude (32.75°N) community surveyed was located at Tatsukushi, Shikoku Island, Japan. Coral cover was 60±2% and was composed of 73 scleractinian species partitioned into 7 functional groups. Although only 6% of species belonged to the ‘plate-like’ functional group, it was the major contributor to species coverage. This was explained by the dominance of plate-like species such as Acropora hyacinthus and A. solitaryensis. Comparison with historical data suggests a relatively recent colonization/development of A. hyacinthus in this region and a potential increase in coral diversity over the last century. Low coverage of macroalgae (2% of the benthic cover) contrasted with the low abundance of herbivorous fishes, but may be reasonably explained by the high density of sea urchins (12.9±3.3 individuals m−2).Conclusions/Significance
The structure and composition of this benthic community are relatively remarkable for a site where winter temperature can durably fall below the accepted limit for coral reef development. Despite limited functionalities and functional redundancy, the current benthic structure might provide a base upon which a reef could eventually develop, as characterized by opportunistic and pioneer frame-building species. In addition to increasing seawater temperatures, on-going management actions and sea urchin density might also explain the observed state of this community. A focus on such ‘marginal’ communities should be a priority, as they can provide important insights into how tropical corals might cope with environmental changes. 相似文献53.
Despite advances in diagnosis and therapy, atherosclerotic cardiovascular disease remains the leading cause of morbidity and mortality in the Western world. Predicting metabolically active atherosclerotic lesions has remained an unmet clinical need. We hereby developed an electrochemical strategy to characterize the inflammatory states of high-risk atherosclerotic plaques. Using the concentric bipolar microelectrodes, we sought to demonstrate distinct Electrochemical Impedance Spectroscopic (EIS) measurements for unstable atherosclerotic plaques that harbored active lipids and inflammatory cells. Using equivalent circuits to simulate vessel impedance at the electrode–endoluminal tissue interface, we demonstrated specific electric elements to model working and counter electrode interfaces as well as the tissue impedance. Using explants of human coronary, carotid, and femoral arteries at various Stary stages of atherosclerotic lesions (n = 15), we performed endoluminal EIS measurements (n = 147) and validated with histology and immunohistochemistry. We computed the vascular tissue resistance using the equivalent circuit model and normalized the resistance to the lesion-free regions. Tissue resistance was significantly elevated in the oxLDL-rich thin-cap atheromas (1.57 ± 0.40, n = 14, p < 0.001) and fatty streaks (1.36 ± 0.28, n = 33, p < 0.001) as compared with lesion-free region (1.00 ± 0.18, n = 82) or oxLDL-absent fibrous atheromas (0.86 ± 0.30, n = 12). Tissue resistance was also elevated in the calcified core of fibrous atheroma (2.37 ± 0.60, n = 6, p < 0.001). Despite presence of fibrous structures, tissue resistance between ox-LDL-absent fibroatheroma and the lesion-free regions was statistically insignificant (0.86 ± 0.30, n = 12, p > 0.05). Hence, we demonstrate that the application of EIS strategy was sensitive to detect fibrous cap oxLDL-rich lesions and specific to distinguish oxLDL-absent fibroatheroma. 相似文献
54.
Bridge Tom C. L. Luiz Osmar J. Kuo Chao-Yang Precoda Kristin Madin Elizabeth M. P. Madin Joshua S. Baird Andrew H. 《Coral reefs (Online)》2020,39(2):271-279
Coral Reefs - Comparative lists of species’ extinction risk are increasingly being used to prioritise conservation resources. Extinction risk is most rigorously assessed using quantitative... 相似文献
55.
CpG-oligodeoxynucleotides (CpG-ODN) are potent immune stimuli being developed for use as adjuvants in different species. Toll-like receptor 9 (TLR9) is the cellular receptor for CpG-ODN in mammalian cells. The CpG-ODN with 18–24 deoxynucleotides that are in current use for human and mouse cells, however, have low activity with rabbit TLR9. Using a cell-based activation assay, we developed a type of CpG-ODN containing a GACGTT or AACGTT motif in 12 phosphorothioate-modified deoxynucleotides with potent stimulatory activity for rabbit TLR9. The developed CpG-ODN have higher activities than other developed CpG-ODN in eliciting antigen-nonspecific immune responses in rabbit splenocytes. When mixed with an NJ85 peptide derived from rabbit hemorrhagic disease virus, they had potent activities to boost an antigen-specific T cell activation and antibody production in rabbits. Compared to Freund’s adjuvant, the developed CpG-ODN are capable of boosting a potent and less toxic antibody response. The results of this study suggest that both the choice of CpG-motif and its length are important factors for CpG-ODN to effectively activate rabbit TLR9 mediated immune responses. 相似文献
56.
Xu J Mao ZG Kong M Hu LH Ye CY Xu CG Rong S Sun LJ Wu J Dai B Chen DP Zhu YX Zhang YX Zhang YQ Zhao XZ Mei CL 《PloS one》2011,6(4):e14781
Background
Diseases of the kidneys and genitourinary tract are common health problems that affect people of all ages and demographic backgrounds. In this study, we compared the quantity and quality of nephrological and urological articles published in international journals from the three major regions of China: the mainland (ML), Hong Kong (HK), and Taiwan (TW).Methods
Nephrological and urological articles originating from ML, TW, and HK that were published in 61 journals from 1999–2008 were retrieved from the PubMed database. We recorded the numbers of total articles, clinical trials, randomized controlled trials, case reports, impact factors (IF), citations, and articles published in the leading general-medicine journals. We used these data to compare the quantity and quality of publication output from the three regions.Results
The total number of articles increased significantly from 1999 to 2008 in the three regions. The number of articles from ML has exceeded that from HK since 2004, and surpassed that from TW in 2008. Publications from TW had the highest accumulated IF, total citations of articles, and the most articles published in leading general-medicine journals. However, HK publications had the highest average IF. Although ML produced the largest quantity of articles, it exhibited the lowest quality among the three regions.Conclusion
The number of nephrological and urological publications originating from the three major regions of China increased significantly from 1999 to 2008. The annual number of publications by ML researchers exceeded those from TW and HK. However, the quality of articles from TW and HK was higher than that from ML. 相似文献57.
In the context of rising seawater temperatures associated with climate change, the issue of whether coral holobionts deal with this challenge by shuffling their associations with stress‐ and/or heat‐tolerant Symbiodinium, by generating heat‐resistant host genotypes, or both is important for coral survival. In this study, the composition of communities of the endosymbiont Symbiodinium and the population genetics of the coral host Platygyra verweyi were examined in a reef impacted by hot‐water discharged from the outlet of a nuclear power plant in operation in Kenting, Southern Taiwan since 1984. The water at this site is 2.0–3.0 °C warmer than adjacent reefs in summer, which have an average seawater temperature of 29.0 °C. The data were compared with those for the same species at other sites within 12 km of the outlet site. Platygyra verwyei was associated with one or both of Symbiodinium types C3 (heat sensitive) and D1a (heat tolerant) at all sites with the latter being the dominant at the nuclear power plant outlet. The proportion of C3 in populations increased gradually with increasing distance from the hot‐water discharge. Genetic analysis of the Platygyra verweyi host using mitochondrial and nuclear markers showed no genetic differentiation among sites. Changes in the composition of Symbiodinium types associated with P. verweyi among closely located sites in Kenting suggested that this coral might have acclimatized to the constant thermal stress by selective association with heat‐tolerant Symbiodinium types, whereas the role of the host in adaptation was inconclusive. 相似文献
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