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31.
Fraternale D Sosa S Ricci D Genovese S Messina F Tomasini S Montanari F Marcotullio MC 《Fitoterapia》2011,82(4):654-661
The topical anti-inflammatory, free radical scavenging and antifungal activities of essential oils and extracts of Commiphora erythraea (Ehrenb.) Engl. resin were investigated. The hexane extract significantly inhibited oedema when applied topically in Croton oil-induced ear oedema assay in mice. The same extract showed antioxidant activity in DPPH radical scavenging assay. A bioguided separation of the hexane extract led to the isolation of furanosesquiterpenoids 1 and 2 that showed a weak antifungal activity, while compounds 3-5 resulted to be antioxidant (EC50 4.28, 2.56 and 1.08 mg/mL, respectively) and anti-inflammatory (30, 26 and 32% oedema reduction, respectively). 相似文献
32.
Luisa Patrolecco Silvio Capri Silvia De Angelis Romano Pagnotta Stefano Polesello Sara Valsecchi 《Water, air, and soil pollution》2006,172(1-4):151-166
Nonylphenol (NP), nonylphenol mono- and di-ethoxylate (NP1EO, NP2EO) and bisphenol A (BPA) were determined in water, suspended particulate matter (s.p.m.) and bed sediment collected from the most polluted stretch of Tiber river (Italy) in the neighbourhood of Rome. Analytes were recovered from water samples by solid-phase extraction (SPE) on Si–C18 cartridges and analysed by HPLC with fluorescence detection. Solid samples were extracted by using an aqueous solution of the non-ionic surfactant Tween 80. Results indicated that 2–42% of NP, 9–45% of NP1EO, 11–18% of NP2EO and 4–62% of BPA respectively occurred in the suspended phase. In general, for all compounds a higher affinity for s.p.m. than for bed sediments was observed, reflecting differences in the nature of particles and in their sorption capacity for organic micro-pollutants. The partition of target compounds in river compartments was affected by differences in hydrological conditions between the two sampling campaigns. Run-off from the basin or resuspension/redissolution from sediments was an important source of nonylphenol and bisphenol A during high discharge regimes. Partition coefficients of compounds (log K oc ) between water and s.p.m. were calculated under stable flow condition. K oc values, experimentally measured in the river, were higher than those predicted by K ow , implying that specific chemical interaction could occur in the sorption mechanisms for these group of compounds. 相似文献
33.
Sixteen adult fresh water teleosts ( Pimelodus maculatus) were used in an examination of the effect of salt water on the ultrastructure of the epidermis. Six animals were treated for 3 hours with 2% saline and six were treated with 1% saline for 8 hours. No diffrenences between treated groups were noted. Four animals served as untreated controls. Both transmission and freeze-facture electonmicroscopy was utilized in examining the epidermis.
The significant alterations in epidermis were observed within the superficial cell layer, in which a decreased density of micropolicae occurred, suggesting streching of the cell surface. An increased intercellular space was also observed in this layer. The cells demonstrated an increase in intracytoplasmic vesicles, and an enhancement of Golgi membranes in treated animals as compared to untreated animals. 相似文献
The significant alterations in epidermis were observed within the superficial cell layer, in which a decreased density of micropolicae occurred, suggesting streching of the cell surface. An increased intercellular space was also observed in this layer. The cells demonstrated an increase in intracytoplasmic vesicles, and an enhancement of Golgi membranes in treated animals as compared to untreated animals. 相似文献
34.
Gnos E Hofmann BA Al-Kathiri A Lorenzetti S Eugster O Whitehouse MJ Villa IM Jull AJ Eikenberg J Spettel B Krähenbühl U Franchi IA Greenwood RC 《Science (New York, N.Y.)》2004,305(5684):657-659
The lunar meteorite Sayh al Uhaymir 169 consists of an impact melt breccia extremely enriched with potassium, rare earth elements, and phosphorus [thorium, 32.7 parts per million (ppm); uranium, 8.6 ppm; potassium oxide, 0.54 weight percent], and adherent regolith. The isotope systematics of the meteorite record four lunar impact events at 3909 +/- 13 million years ago (Ma), approximately 2800 Ma, approximately 200 Ma, and <0.34 Ma, and collision with Earth sometime after 9.7 +/- 1.3 thousand years ago. With these data, we can link the impact-melt breccia to Imbrium and pinpoint the source region of the meteorite to the Lalande impact crater. 相似文献
35.
Wolfgang Josef Hintsteiner Marcela van Loo Charalambos Neophytou Silvio Schueler Hubert Hasenauer 《European Journal of Forest Research》2018,137(4):447-461
Since the nineteenth century, Douglas-fir seed sources have been widely used for establishment of forest stands outside its natural distribution range. In Europe, some of these old Douglas-fir stands are registered as seed stands and provide seed sources for nurseries, although it is unclear from which region in North America they originate. In recent years, the interest in planting Douglas-fir has increased substantially because the species is seen as a potential adaptation option to climate change. This makes the assignment of European Douglas-fir stands of unknown seed origin to their geographic origin in North America increasingly important, because the genetic quality of these plantations must be guaranteed. In this study, we use 13 nuSSR loci to investigate the origin of 67 Austrian and German Douglas-fir stands of unknown origin. We performed a hierarchical Bayesian cluster analysis using 38 native Douglas-fir populations. The resulting clusters are used as reference populations to assign the 67 Central European Douglas-fir stands from Austria and Germany planted more than 80 years ago. Our results suggest that the majority of our investigated Douglas-fir stands come from central Washington (USA), the recommended seed zones for Central Europe. Some stands were located outside the suggested area, e.g. central Oregon and Santa Fe (New Mexico). The accuracy assessment of our approach revealed the best performance for the highest hierarchical level, e.g. assigning populations either to the coastal or the Rocky Mountain variety. As expected, the uncertainty increases with decreasing hierarchical level. The final assessment, if an admixture of seed sources within the European Douglas-fir stands is evident suggests that 23 of the Douglas-fir stands show an admixture which was not detected in our Douglas-fir reference populations growing in the natural distribution range. 相似文献
36.
Thaís Castelo-Branco Maria Madalena Pessoa Guerra Roberta Soares Silvio Peixoto 《Aquaculture International》2018,26(3):913-920
Vitrification is a fast freezing method with promising results for penaeids sperm cryopreservation. This study evaluated the efficiency of three cryoprotectant solutions for sperm vitrification and artificial insemination with cryopreserved spermatophores of Litopenaeus vannamei. The cryoprotectant solutions tested were 30% methanol, 2% soy lecithin, and 30% methanol?+?2% soy lecithin. Fully mature females were artificially inseminated with vitrified and fresh spermatophores as a control group. The vitrification method was efficient in maintaining high rates of sperm survival and membrane integrity. Although the egg fertilization was successfully attained by artificial insemination with cryopreserved spermatophores, low hatching rates suggested that possible DNA fragmentation of sperm cells should be further investigated. This is the first report of artificial insemination using vitrified sperm in penaeids. 相似文献
37.
aquasaúde: A mobile application for educational training on prevention of shrimp pathogen‐associated diseases 下载免费PDF全文
38.
Joo Victor Rocha Jos Filipe Silva Camila Barros Silvio Peixoto Roberta Soares 《Aquaculture Research》2019,50(12):3653-3662
Feeding restriction is a strategy in shrimp farming management that may promote compensatory growth after feeding is re‐established. This study aims to evaluate the effects of two feeding restriction regimens on the compensatory growth and digestive enzymes activity of Litopenaeus vannamei reared in biofloc system. Juvenile shrimp (0.46 ± 0.18 g) were stocked (320 individuals/m3) in 310 L tanks. The experiment comprised two phases: (a) Feeding Restriction (30 days) when shrimp were submitted to three feeding regimes, Control (fed daily), R1F1 (repetitively fasted one day and fed one day) and R2F1 (repetitively fasted 2 days and fed 1 day); and (b) Refeeding (28 days) when shrimp were fed daily. In the restriction phase, shrimp growth and digestive enzyme activities were reduced in R2F1 and R1F1. However, during the refeeding phase, enzyme activities and feed conversion improve significantly in R2F1 and R1F1. Control group attained higher final weight, but its final biomass was similar to R1F1. Litopenaeus vannamei exhibited partial compensatory growth, probably due to improved feed conversion efficiency driven by increased enzyme activity. It is possible to reduce feeding by 50% (R1F1) in biofloc systems for 28 days, without compromising the biomass produced at the end of a 30‐day refeeding period. 相似文献
39.
40.
Paulo G. Molin Sarah E. Gergel Britaldo S. Soares-Filho Silvio F. B. Ferraz 《Landscape Ecology》2017,32(4):857-870