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991.
Thomas C. Wanger Iris Motzke Samuel C. Furrer Barry W. Brook Bernd Gruber 《Ecological Research》2009,24(2):345-353
Rapid and reliable estimation of population size is needed for the efficient monitoring of animal populations of conservation
concern. Unfortunately, technical advances in this area have not been paralleled in uptake in conservation, which may be due
to difficulties in implementation or the lack of general guidelines for application. Here we tested five different methods
used to estimate population size [capture–mark–recapture (CMR), finite-mixture models, model averaging of finite-mixture models,
accumulation curve methods (ACM), and the line transect method (LT)] using extensive capture–recapture data of the giant day
gecko (Gekkonidae, Phelsuma madagascariensis grandis, Gray 1870) at the Masoala rainforest exhibit, Zurich Zoo. When the complete data were analyzed [30 sessions (and 27 sessions
for the LT)], all methods except the LT produced similar estimates of population size. The simple ACM gave a small coefficient
of variation (CV), but did not cover the most likely value of population size at moderate sampling effort. Nevertheless, the
ACM was the only method that showed a reasonable convergence when subsets of data were used. CMR and Pledger models included
the reference value in their confidence intervals (CI) after 25 and 30 sessions, respectively. Although model averaging did
slightly improve the estimate, the CV was still high for the full dataset. Our method of using subsets of data to test the
robustness of estimates is simple to apply and could be adopted more widely in such analyzes to evaluate sensitivity to method
of evaluation. In conclusion, simple accumulation methods showed similar efficiency to more complex statistical models, and
are likely to be sufficiently precise for most conservation monitoring purposes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
992.
Yoshinori Harada Ping Dai Yoshihisa Yamaoka Mitsugu Ogawa Hideo Tanaka Kazuto Nosaka Kenichi Akaji Tetsuro Takamatsu 《Histochemistry and cell biology》2009,132(1):39-46
Most molecular imaging technologies require exogenous probes and may have some influence on the intracellular dynamics of
target molecules. In contrast, Raman scattering light measurement can identify biomolecules in their innate state without
application of staining methods. Our aim was to analyze intracellular dynamics of topoisomerase I inhibitor, CPT-11, by using
slit-scanning confocal Raman microscopy, which can take Raman images with high temporal and spatial resolution. We could acquire
images of the intracellular distribution of CPT-11 and its metabolite SN-38 within several minutes without use of any exogenous
tags. Change of subcellular drug localization after treatment could be assessed by Raman imaging. We also showed intracellular
conversion from CPT-11 to SN-38 using Raman spectra. The study shows the feasibility of using slit-scanning confocal Raman
microscopy for the non-labeling evaluation of the intracellular dynamics of CPT-11 with high temporal and spatial resolution.
We conclude that Raman spectromicroscopic imaging is useful for pharmacokinetic studies of anticancer drugs in living cells.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
993.
994.
Silas Pessini Rodrigues José Aires Ventura R. B. Zingali P. M. B. Fernandes 《Phytochemical analysis : PCA》2009,20(6):456-464
Introduction – A variety of sample preparation protocols for plant proteomic analysis using two‐dimensional gel electrophoresis (2‐DE) have been reported. However, they usually have to be adapted and further optimised for the analysis of plant species not previously studied. Objective – This work aimed to evaluate different sample preparation protocols for analysing Carica papaya L. leaf proteins through 2‐DE. Methodology – Four sample preparation methods were tested: (1) phenol extraction and methanol–ammonium acetate precipitation; (2) no precipitation fractionation; and the traditional trichloroacetic acid–acetone precipitation either (3) with or (4) without protein fractionation. The samples were analysed for their compatibility with SDS–PAGE (1‐DE) and 2‐DE. Fifteen selected protein spots were trypsinised and analysed by matrix‐assisted laser desorption/ionisation time‐of‐flight tandem mass spectrometry (MALDI‐TOF‐MS/MS), followed by a protein search using the NCBInr database to accurately identify all proteins. Results – Methods number 3 and 4 resulted in large quantities of protein with good 1‐DE separation and were chosen for 2‐DE analysis. However, only the TCA method without fractionation (no. 4) proved to be useful. Spot number and resolution advances were achieved, which included having an additional solubilisation step in the conventional TCA method. Moreover, most of the theoretical and experimental protein molecular weight and pI data had similar values, suggesting good focusing and, most importantly, limited protein degradation. Conclusion – The described sample preparation method allows the proteomic analysis of papaya leaves by 2‐DE and mass spectrometry (MALDI‐TOF‐MS/MS). The methods presented can be a starting point for the optimisation of sample preparation protocols for other plant species. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
995.
996.
Siegfried Jahnke Marion I. Menzel Dagmar van Dusschoten Gerhard W. Roeb Jonas Bühler Senay Minwuyelet Peter Blümler Vicky M. Temperton Thomas Hombach Matthias Streun Simone Beer Maryam Khodaverdi Karl Ziemons Heinz H. Coenen Ulrich Schurr 《The Plant journal : for cell and molecular biology》2009,59(4):634-644
Unravelling the factors determining the allocation of carbon to various plant organs is one of the great challenges of modern plant biology. Studying allocation under close to natural conditions requires non-invasive methods, which are now becoming available for measuring plants on a par with those developed for humans. By combining magnetic resonance imaging (MRI) and positron emission tomography (PET), we investigated three contrasting root/shoot systems growing in sand or soil, with respect to their structures, transport routes and the translocation dynamics of recently fixed photoassimilates labelled with the short-lived radioactive carbon isotope 11 C. Storage organs of sugar beet ( Beta vulgaris ) and radish plants ( Raphanus sativus ) were assessed using MRI, providing images of the internal structures of the organs with high spatial resolution, and while species-specific transport sectoralities, properties of assimilate allocation and unloading characteristics were measured using PET. Growth and carbon allocation within complex root systems were monitored in maize plants ( Zea mays ), and the results may be used to identify factors affecting root growth in natural substrates or in competition with roots of other plants. MRI–PET co-registration opens the door for non-invasive analysis of plant structures and transport processes that may change in response to genomic, developmental or environmental challenges. It is our aim to make the methods applicable for quantitative analyses of plant traits in phenotyping as well as in understanding the dynamics of key processes that are essential to plant performance. 相似文献
997.
Shinya Kato Hisae Aoshima Yasukazu Saitoh Nobuhiko Miwa 《Bioorganic & medicinal chemistry letters》2009,19(18):5293-5296
Antioxidant ability of the water-soluble derivative of fullerene (C60), prepared by high-degree hydroxylation [C60-(OH)32·8H2O] or C60/γ-cyclodextrin (1:2 mol/mol) clathrate formation [C60/(γ-CD)2], was assessed by electron spin resonance method and β-carotene bleaching assay. These C60 derivatives have an ability to diminish a 1:2:2:1 quartet ESR spectrum attributed to hydroxyl radicals (OH) as shown by DMPO-spin trap/ESR method. Meanwhile, a singlet radical-signal different from OH-attributed signals increased in a manner dependent on concentrations of C60-(OH)32·8H2O. This might suggest that C60-(OH)32·8H2O scavenges OH owing to dehydrogenation of C60-(OH)32·8H2O, and is simultaneously oxidized to a stable radical species, which may be a dehydrogenated fullerenol radical (C60-O). Furthermore, these water-soluble derivatives of C60 suppressed fading of yellowish color characteristic of intact β-carotene in β-carotene bleaching assay. Antioxidant abilities of these derivatives were assessed as retention of yellowish color (viz absorbance at 470 nm) for 180 min. Namely, β-carotene-attributed chromaticity (% relative absorbance at 470 nm compared with the control) after 180 min was 69% for C60-(OH)32·8H2O (400 μM: C60-eq.), and 32% for C60/(γ-CD)2 (400 μM: C60-eq.), whereas it was 6% for l(+)-ascorbic acid (400 μM) which is hydrophilic, and 85% for (±)-α-tocopherol (400 μM) which is lipophilic, respectively. Thus C60-(OH)32·8H2O and C60/(γ-CD)2 can scavenge OH, and have a distinct antioxidative activity in the aqueous system containing linoleic acid which is abundantly contained in the cell membrane together with other unsaturated lipids. These C60 derivatives have a potential to protect the cell membrane from oxidative stress due to OH. 相似文献
998.
999.
充分、有效地利用各种陆地生态系统碳观测数据改善陆地生态系统模型, 是当前我国陆地生态系统碳循环研究领域亟待解决的重要问题之一。该研究以2003~2005年长白山阔叶红松林的6组生物计量观测数据和涡度相关技术测定的碳通量数据为基础, 利用马尔可夫链-蒙特卡罗方法对陆地生态系统模型的关键参数(即碳滞留时间)进行了反演, 进而预测了长白山阔叶红松林生态系统碳库、碳通量及其不确定性。反演结果表明, 长白山阔叶红松林叶凋落物和微生物碳的平均滞留时间最短, 为2~6个月; 其次是叶和细根生物量碳, 二者的平均滞留时间为1~2 a; 慢性土壤有机碳的平均滞留时间为8~16 a; 碳在木质生物量和惰性土壤有机质库中的滞留时间最长, 平均滞留时间分别为77~109 a和409~1 879 a。模拟结果显示, 碳库和累积碳通量模拟值的不确定性将随着模拟时间的延长而增大。当气温升高10%和20%时, 长白山阔叶红松林总初级生产力年总量将分别增加6.5%和9.9%, 净生态系统生产力(NEP)年总量的变化取决于土壤温度的变化。若土壤温度保持不变, NEP年总量将分别增加11.4%~21.9%和17.6%~33.1%; 若土壤温度也相应升高10%和20%, NEP年总量的增幅反而下降甚至低于原来的水平。假设气候和植被保持在2003~2005年的状态, 2020年长白山阔叶红松林NEP年总量为(163±12) g C·m–2·a–1, 土壤呼吸年总量为(721±14) g C·m–2·a–1。马尔可夫链-蒙特卡罗方法是反演模型参数、优化模拟结果和评估模拟结果不确定性的有效方法, 但今后仍需在惰性土壤碳滞留时间的估计、驱动数据和模型结构的不确定性分析、模型数据融合方法方面进行深入研究, 以进一步提高碳循环模拟的准确性。 相似文献
1000.
乳杆菌活菌制剂联合可宝净治疗老年性阴道炎疗效观察 总被引:1,自引:0,他引:1
目的探讨乳杆菌活菌制剂联合可宝净治疗老年性阴道炎的效果。方法将2006年6月至2008年4月在大连医科大学附属二院确诊为老年性阴道炎的患者随机分为3组。A组:76例,使用乳杆菌活菌胶囊(定君生)与可宝净联合用药;B组:78例,单纯使用甲硝唑泡腾片;C组77例,单纯使用可宝净。结果有效率:A组为92.11%,B组为83.33%,C组为85.71%;复发率:A组为15.79%,B组为39.74%,C组为41.56%,B组、C组差异无显著性(P〈0.05)。结论使用乳杆菌活菌胶囊(定君生)与可宝净联合用药治疗老年性阴道炎是一种有效、安全的方法。 相似文献