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901.
Daniela Mattei Stefano Cataudella Laura Mancini Lorenzo Tancioni Luciana Migliore 《Water, air, and soil pollution》2006,177(1-4):441-455
The evaluation of Tiber River quality, in a stretch including a sewage treatment plant, has been carried out by the contemporary evaluation of water effect on Daphnia and benthic macroinvertebrates community structure. To achieve a good status of a river water by the end of 2015, as provided in the Water Framework Directive (WFD) 2000/60/EC, is necessary to know the quality starting point. To this end, several endpoints are expected by the WFD, including Daphnia toxicity test and macroinvertebrate community analysis. River water sampling was conducted in the four seasons, from upstream to downstream a sewage treatment plant. I endpoint. At the outfall of the sewage treatment plant, river water showed very high acute toxicity to Daphnia only in summer; some toxic effect can be found also upstream in spring. Results at the outfall were consistent with the hypothesis that disinfectants, mainly used in summer to treat discharging waters, are responsible of river water acute toxicity: Daphnia tests with each disinfectant (NaClO, PAA, ClO2) showed high toxicity. River waters were also utilized in Daphnia reproduction tests. Samples at the outfall (excluding the summer one, undoubtedly toxic) caused slight reduction in survival and fecundity. Disinfectants were also checked in reproduction tests. Still at NOEC24h, they caused a significant toxicity on both death rate and reproduction. II endpoint. Macroinvertebrate benthic community composition was evaluated upstream and downstream the sewage treatment plant, on these data Extended Biotic Index (EBI), was determined to get a score as quality class. A reduction of water quality score was found downstream the plant, one season delayed (autumn) respect the acute test on Daphnia. Effect of disinfectant discharge, river dilution capability on a short spatial scale and use of different endpoints are discussed in term of river stretch quality. 相似文献
902.
903.
Antoine MESS AN Lo c VIGUIER Lise PARESYS Jean-No l AUBERTOT Stefano CANALI Pietro IANNETTA Eric JUSTES Alison KARLEY Beatrix KEILLOR Laura KEMPER Fr d ric MUEL Barbara PANCINO Didier STILMANT Christine WATSON Helga WILLER Ra l ZORNOZA 《农业科学与工程前沿(英文版)》2021,8(3):474-480
904.
水飞蓟素的药理学研究进展 总被引:6,自引:0,他引:6
系统查阅近年来有关水飞蓟素的药理学研究报道,总结了草本植物水飞蓟的活性成分--水飞蓟素的药理学研究进展,综述了水飞蓟素的成分对免疫系统的调节作用、抗肝纤维化、对乳腺癌细胞系的抑制作用、对糖尿病大鼠主动脉非酶糖化及氧化的抑制作用、预防顺铂肾毒性而不影响其抗癌活性、对糖尿病植物神经病变以及保护肝细胞膜,促进被损伤肝细胞合成DNA及结构蛋白等药理作用.本文还展望了水飞蓟素的良好应用前景. 相似文献
905.
Angelo Loy Sara Busilacchi Corrado Costa Ludovic Ferlin Stefano Cataudella 《Aquacultural Engineering》2000,21(4):673-283
The definition of a remote system in the monitoring of fin fish shape variability relies on the appropriate shape analysis tools. In this paper, different methods are proposed and compared. Growth trajectories, computed using geometric morphometrics, allow the pattern of size-related shape change and visualize growth allometry to be analyse. Geometric morphometrics is used to describe shape change in three samples (507 5100 days after hatching) of 119 individuals of the Sparid Diplodus puntazzo. The results are potentially interesting but the method still relies on the manual detection of homologous landmarks (coordinates of points located unambiguously on each specimen’s profile or structure) which are basic for such analysis. In an attempt to proceed towards the remote estimation and the automation of data collection, two alternative approaches are tested. In particular, Elliptic Fourier analysis and Bezier function were applied to the same samples, and results compared with geometric morphometrics. Fourier analysis’ growth curves are very similar to geometric morphometrics’ ones and allows for an appropriate visualisation of global shape changes. At the same time, Fourier methods can be applied to remotely and automatically detected profiles. This method is thus considered as the best candidate in the context of automated fish shape monitoring. The Bezier method performed poorly, both in terms of statistical output and shape visualization. 相似文献
906.
907.
[目的]比较不同棉花品种(系)的农艺性状和产量特性。[方法]采用随机区组试验设计,以2份中国农业科学院棉花所、13份新疆棉花品种(系)为材料,对棉花农艺性状、产量进行比较分析,鉴定参试棉花品种(系)在哈密棉区的适应性、丰产性、抗逆性等综合表现。[结果]棉花品种(系)尼科3号、44-23、库1506生育期适中、产量较高、品质较好、抗逆性较强,综合表现高于其他品种(系)。[结论]通过综合比较,初步筛选出尼科3号、44-23、库1506这3个适合哈密棉区种植的品种(系),可进一步试种后大面积推广种植。 相似文献
908.
Differences of raw cork quality, in terms of thickness and porosity, were observed in productive cork oak (Quercus suber L.) stands in the Nebrodi and Iblei mountains of Sicily in relation to stand density. Five study areas were chosen across a range of different stand density satisfying specific sampling requirements among two managed cork oak woods.Analysis of variance using Fisher–Snedecor‘s F test (p < 0.05) were used to identify statistically significant differences of cork quality and sylvicultural, dendrometric and cork stripping parameters between study areas within each stand. Relationships between cork quality and sylvicultural and dendrometric parameters were also tested using Pearson's correlation coefficient (r). Results shown that sylvicultural practices are a key factor influencing cork quality: statistically significant differences in cork thickness and crown area were observed between areas at different stand density; positive correlations were found between cork thickness and crown area in lower density study areas favouring a significant vegetative activity; negative correlations were found between parameters of cork stripping (cork stripping coefficient, cork stripping surface, maximum height of cork stripping) and cork thickness. No correlations were found between cork porosity and dendrometric or sylvicultural parameters, demonstrating the probable genetic origin of cork porosity. Results shown that cork quality parameters and stand attributes may be used in sustainable management models of cork oak forests. 相似文献
909.
Stefano Dall'Acqua Filippo Maggi Paola Minesso Marina Salvagno Fabrizio Papa Sauro Vittori Gabbriella Innocenti 《Fitoterapia》2010,81(8):1208-1212
Inhibition of Acetylcholinesterase (AChE) is still considered as a strategy for the treatment of neurological disorders such as Alzheimer's disease. Many plant derived alkaloids (such as galantamine and rivastigmine) are known for their AChE inhibitory activity. Recently, other classes of natural compounds such as terpenoids, sesquiterpene glycosides and coumarins have been studied as new AChE inhibitors, with the aim to discover less toxic compounds compared to alkaloidal ones. The Ferulago campestris roots dichloromethane extract was used for a bioassay-guided fractionation for the search of AChE inhibitors. Three coumarin derivatives (umbelliprenin 1, coladonin 2 and coladin 3), three daucane ester derivatives (siol anisate 4, ferutinin 5 and 1-acetyl-5-angeloyl lapiferol 6), two phenol derivatives (2-epilaserine 7 and epielmanticine 8) and one polyacetylene (9-epoxyfalcarindiol 9) were isolated by the bioassay-guided approach. Their structures were characterized on the basis of spectral methods (1D and 2D NMR, and MS spectroscopy). All the isolated compounds were able to inhibit the AChE (IC50 1.2–0.1 mM) although at higher doses if compared to galantamine (6.7 μM) measured in the same conditions. The most active compounds were the daucane derivative siol anisate 4 and the epielmanticine 8, with IC50 of 0.172 and 0.175 mM respectively. 相似文献
910.
Stefano Comai Stefano Dall'Acqua Alessia Grillo Ignazio Castagliuolo Khilendra Gurung Gabbriella Innocenti 《Fitoterapia》2010
The composition of the essential oil of Lindera neesiana Kurz fruit was examined by GC-MS, 1H, 13C and bidimensional NMR techniques (HMQC, HMBC, COSY, TOCSY). Forty compounds were identified, representing approximately 86% of the oil: Z-citral (15.08%), E-citral (11.89%), eucalyptol (8.75%), citronellal (6.72%), α-pinene (6.63%) and β-pinene (5.61%) were the major components. The essential oil of L. neesiana fruit showed significant antimicrobial activity against Staphylococcus aureus and Candida albicans at non-cytotoxic doses in human keratinocytes, suggesting possible topical applications. 相似文献