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排序方式: 共有536条查询结果,搜索用时 15 毫秒
1.
Anna Esposito Daniele DAlonzo Stefano DErrico Eliana De Gregorio Annalisa Guaragna 《Marine drugs》2020,18(11)
In the effort to improve the antimicrobial activity of iminosugars, we report the synthesis of lipophilic iminosugars 10a–b and 11a–b based on the one-pot conjugation of both enantiomeric forms of N-butyldeoxynojirimycin (NBDNJ) and N-nonyloxypentyldeoxynojirimycin (NPDNJ) with cholesterol and a succinic acid model linker. The conjugation reaction was tuned using the established PS-TPP/I2/ImH activating system, which provided the desired compounds in high yields (94–96%) by a one-pot procedure. The substantial increase in the lipophilicity of 10a–b and 11a–b is supposed to improve internalization within the bacterial cell, thereby potentially leading to enhanced antimicrobial properties. However, assays are currently hampered by solubility problems; therefore, alternative administration strategies will need to be devised. 相似文献
2.
Bravo Carlo Millo Christian Covelli Stefano Contin Marco De Nobili Maria 《Journal of Soils and Sediments》2020,20(2):1074-1086
Journal of Soils and Sediments - Humic acids (HA) have several environmental roles, but are particularly important in aquatic environments, being recognized as redox active natural organic matter... 相似文献
3.
Stefano Carbonara Raffaele D'Adamo Andrea Novelli Sergio Pelosi Adele Fabbrocini 《Aquaculture Research》2019,50(9):2469-2476
The development of sustainable methods for sea urchin juvenile production is currently constrained by high mortality rates during larval growth and the high costs of larval rearing systems management. With the aim of developing a method for the production of juveniles of the purple sea urchin Paracentrotus lividus in a medium‐scale recirculating system, the present study focused on the effects of high stocking densities on larval growth. Plutei larvae were reared at three different densities (up to 7 ind/ml) in a semi‐static culture system. Larval survival and metamorphosis success were evaluated in order to identify the most effective density range. The highest metamorphosis rates (80%–95%) were obtained at 4 and 7 larvae/ml. These results are comparable with (and in some cases higher than) those reported for the same species at much lower larval densities. In conclusion, the rearing conditions tested here show for the first time that a significantly higher (4 ind/ml) stocking density than those of traditional P. lividus rearing methods (based on large volumes and low densities) can be adopted, thus supporting the feasibility of an increase in the final output of competent larvae with no increase in rearing volumes. 相似文献
4.
5.
Patrizia CASAGRANDE PROIETTI Valentina STEFANETTI Doreene Rose HYATT Maria Luisa MARENZONI Stefano CAPOMACCIO Mauro COLETTI Annalisa BIETTA Maria Pia FRANCIOSINI Fabrizio PASSAMONTI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(8):945-951
Biofilm-forming ability is increasingly being recognized as an important virulence factor in several Staphylococcus species. This study evaluated the biofilm-forming ability of sixty canine derived clinical isolates of S. pseudintermedius, using three phenotypic methods, microtiter plate test (MtP), Congo red agar method (CRA) and tube adherence test, and the presence and impact of biofilm-associated genes (icaA and icaD). The results showed that icaA and icaD genes were detected concomitantly in 55 (91.7%) of 60 isolates. A majority (88.3%) of the strains screened had matching results by the tube adherence test, MtP and PCR analysis. Better agreement (95%) was found between the PCR-based analysis and the CRA. Results of the icaA and icaD gene PCRs showed good agreement with CRA results, with a kappa of 0.7. Comparing the phenotypic methods,
the statistical analysis showed that the agreement among the phenotypical tests using categorical data was generally good. Considering two classes (biofilm producer and biofilm non-producer), the percentage of matching results between the CRA method and the tube adherence test and between the CRA method and the MtP was 93.3%. A concordance of 100% was revealed between the MtP and the tube adherence test. The results indicate a high prevalence of the ica genes within S. pseudintermedius isolates, and their presence is associated with in vitro formation of a biofilm. A combination of phenotypic and genotypic tests is recommended for investigating biofilm formation in S. pseudintermedius. 相似文献
6.
The antiproliferative activity of fresh fruit juices extracted from Citrus sinensis (cv. Washington Navel and cv. Sanguinello), C. deliciosa cv. Avana, C. clementina cv. Nules, C. aurantium subsp. myrtifolia , was evaluated against K562 (human chronic myelogenous leukemia), HL-60 (human leukemia) and MCF-7 (human breast adenocarcinoma) cell lines. All the juices tested showed antiproliferative activity. Moreover, the pattern of the main flavanone compounds in the juices has been determined by HPLC analysis. 相似文献
7.
Mancuso S 《Tree physiology》1999,19(2):95-101
Electrical impedance parameters were measured in shoots and leaves of Olea europaea L. for 18 months to determine seasonal variations in intracellular and extracellular resistances and in the state of membranes; these factors were related to rooting ability. Double- and single-DCE (ZARC) models were used as equivalent circuits for shoots and leaves, respectively. Seasonal variations were observed in all of the impedance parameters measured. Intracellular resistance of the shoots increased during the winter resting period, whereas intracellular resistance of the leaves decreased. Relaxation times for both leaves and shoots decreased during the winter. Close relationships were found between rooting ability and intracellular and extracellular resistances and relaxation times of shoots and leaves. 相似文献
8.
Zosima absinthifolia (ZA) extracts and the coumarins (+)-columbianadin and (-)-deltoin were evaluated for their potential hepatoprotective and antiinflamatory effects in a CCl(4)-induced hepatotoxicity assay in rats and by the inhibition of TNF-α production on LPS-stimulated THP-1 macrophages, respectively. Both the ZA extracts and the coumarins showed hepatoprotective activity confirmed by monitoring the ALT/AST levels and by histopathological examination. The antiinflamatory activity, proved by the inhibition of TNF-α production, was found to be higher for the n-hexane root extract than for coumarins, suggesting synergic potential of the extract. The concentration of (-)-deltoin and (+)-columbianadin in extracts was determined by HPLC analysis. 相似文献
9.
Maria Montseny Cristina Linares Núria Viladrich Alejandro Olariaga Marc Carreras Narcís Palomeras Nuno Gracias Klemen Isteni
Rafael Garcia Stefano Ambroso Andreu Santín Jordi Griny Josep‐Maria Gili Andrea Gori 《水产资源保护:海洋与淡水生态系统》2019,29(8):1278-1284
- In the Mediterranean Sea, gorgonians are among the main habitat‐forming species of benthic communities on the continental shelf and slope, playing an important ecological role in coral gardens.
- In areas where bottom trawling is restricted, gorgonians represent one of the main components of trammel net bycatch. Since gorgonians are long‐lived and slow‐growing species, impacts derived from fishing activities can have far‐reaching and long‐lasting effects, jeopardizing their long‐term viability. Thus, mitigation and ecological restoration initiatives focusing on gorgonian populations on the continental shelf are necessary to enhance and speed up their natural recovery.
- Bycatch gorgonians from artisanal fishermen were transplanted into artificial structures, which were then deployed at 85 m depth on the outer continental shelf of the marine protected area of Cap de Creus (north‐west Mediterranean Sea, Spain). After 1 year, high survival rates of transplanted colonies (87.5%) were recorded with a hybrid remotely operated vehicle.
- This pilot study shows, for the first time, the survival potential of bycatch gorgonians once returned to their habitat on the continental shelf, and suggests the potential success of future scaled‐up restoration activities.
10.
Stefano Casalegno Giuseppe Amatulli Annemarie Bastrup-Birk Tracy Houston Durrant Anssi Pekkarinen 《European Journal of Forest Research》2011,130(6):971-981
Proactive forest conservation planning requires spatially accurate information about the potential distribution of tree species.
The most cost-efficient way to obtain this information is habitat suitability modelling i.e. predicting the potential distribution
of biota as a function of environmental factors. Here, we used the bootstrap-aggregating machine-learning ensemble classifier
Random Forest (RF) to derive a 1-km resolution European forest formation suitability map. The statistical model use as inputs
more than 6,000 field data forest inventory plots and a large set of environmental variables. The field data plots were classified
into different forest formations using the forest category classification scheme of the European Environmental Agency. The
ten most dominant forest categories excluding plantations were chosen for the analysis. Model results have an overall accuracy
of 76%. Between categories scores were unbalanced and Mesophitic deciduous forests were found to be the least correctly classified
forest category. The model’s variable ranking scores are used to discuss relationship between forest category/environmental
factors and to gain insight into the model’s limits and strengths for map applicability. The European forest suitability map
is now available for further applications in forest conservation and climate change issues. 相似文献