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排序方式: 共有411条查询结果,搜索用时 15 毫秒
61.
Francesca Gherardi Sandro Bertolino Marco Bodon Sandra Casellato Simone Cianfanelli Marco Ferraguti Elisabetta Lori Graziella Mura Annamaria Nocita Nicoletta Riccardi Giampaolo Rossetti Emilia Rota Riccardo Scalera Sergio Zerunian Elena Tricarico 《Biological invasions》2008,10(4):435-454
The paper provides a list of the non-indigenous animal species occurring today in Italian inland waters. Xenodiversity was
found to amount to 112 species (64 invertebrates and 48 vertebrates), which contribute for about 2% to the inland-water fauna
in Italy. Northern and central regions are most affected, and Asia, North America, and the rest of Europe are the main donor
continents. The large majority of non-indigenous species entered Italy as a direct or indirect effect of human intervention.
A difference between invertebrates and vertebrates was found for their mode of arrival (unintentional for invertebrates and
intentional for vertebrates). Accidental transport, in association with both fish (for aquaculture or stock enhancement) and
crops, has been the main vector of invertebrate introductions, whereas vertebrates were mostly released for stocking purposes.
Overall stock enhancement (47.92%) and culture (37.5%) prevailed over the other pathways. Seventeen and 7 species of our list
are included among the 100 worst invasive species of Europe (DAISIE) and of the world (IUCN), respectively. For some (but
not all) non-indigenous species recorded in Italy the multilevel impact exerted on the recipient communities and ecosystems
is known, even if rarely quantified, but knowledge on their chronic impact is still missing. Additional research is needed
to provide criteria for prioritizing intervention against well established invaders and identify which new potential invader
should be targeted as “unwanted”. 相似文献
62.
Soulsbury CD Iossa G Baker PJ Harris S 《Proceedings. Biological sciences / The Royal Society》2008,275(1649):2411-2418
The period following the withdrawal of parental care has been highlighted as a key developmental period for juveniles. One reason for this is that juveniles cannot forage as competently as adults, potentially placing them at greater risk from environmentally-induced changes in food availability. However, no study has examined this topic. Using a long-term dataset on red foxes (Vulpes vulpes), we examined (i) dietary changes that occurred in the one-month period following the attainment of nutritional independence, (ii) diet composition in relation to climatic variation, and (iii) the effect of climatic variation on subsequent full-grown mass. Diet at nutritional independence contained increased quantities of easy-to-catch food items (earthworms and insects) when compared with pre-independence. Interannual variation in the volume of rainfall at nutritional independence was positively correlated to the proportion of earthworms in cub diet. Pre-independence cub mass and rainfall immediately following nutritional independence explained a significant proportion of variance in full-grown mass, with environmental variation affecting full-grown mass of the entire cohorts. Thus, weather-mediated availability of easy-to-catch food items at a key developmental stage has lifelong implications for the development of juvenile foxes by affecting full-grown mass, which in turn appears to be an important component of individual reproductive potential. 相似文献
63.
Cesarini S Spallarossa A Ranise A Fossa P La Colla P Sanna G Collu G Loddo R 《Bioorganic & medicinal chemistry》2008,16(7):4160-4172
64.
Ferri N Beccalli EM Contini A Corsini A Antonino M Radice T Pratesi G Tinelli S Zunino F Gelmi ML 《Bioorganic & medicinal chemistry》2008,16(4):1691-1701
A series of 2,3-heteroarylmaleimides 9 and polyheterocondensed imides 12 were prepared in good yields and short reaction time using a very efficient procedure consisting in the condensation of the corresponding anhydrides and N,N-diethylethylenediamine and microwave heating. The antiproliferative activity of the novel molecules was tested against human tumor cells (NCI-H460 lung carcinoma) and rat aortic smooth muscle cells (SMCs). The IC50 values for the novel molecules ranged from 0.08 to 13.9 microM in SMCs, and from 0.84 to 9 microM in the tumor cell line. The activity profile for compounds 9 and 12 is comparable to that obtained for amonafide in NCI-H460, except for fused imides 12b,i which proved to be about 10-fold more potent. Whereas, in rat SMCs, only the compound 12b was shown to be 10-fold more potent than amonafide. Instead 12c is equipotent to amonafide. These results suggest that the extended pi-system and the kind of heteroatom are essential in the binding with the molecular target. 相似文献
65.
Graziella Malandrino Zaira Lipani Roberta G. Toro Maria E. Fragalà 《Inorganica chimica acta》2008,361(14-15):4118-4121
Bi2Mn4O10 films were deposited on SrTiO3 (1 0 0) substrates via metal–organic chemical vapor deposition (MOCVD) from the Bi(phenyl)3 and Mn(tmhd)3 (Htmhd = 2,2,6,6-tetramethyl-3,5-heptanedione) precursors. The films were deposited in the temperature range of 600–800 °C. The X-ray diffraction (XRD) characterization indicates that the Bi2Mn4O10 phase is stable within the investigated range, but the temperature plays a crucial role in determining the out-of-plane orientation of the films. The SEM shows very homogeneous surfaces with a fiber texture morphology at the highest deposition temperature. The AFM data indicate a textured surface with a root mean square roughness of 77.67 nm for films deposited at 800 °C. 相似文献
66.
67.
Theodore J. Abatzopoulos Francisco Amat Athanasios D. Baxevanis Genuario Belmonte Francisco Hontoria Stefania Maniatsi Salvatore Moscatello Graziella Mura Nickolaj V. Shadrin 《International Review of Hydrobiology》2009,94(5):560-579
Artemia urmiana (a species previously considered endemic of Lake Urmia, NW Iran) has been found in Lake Koyashskoe, a hypersaline lake on the Black Sea coast of the Crimean peninsula (Ukraine). Therefore, this is the first record of A. urmiana in Europe which updates its distribution. The species identification was based on an integrated and interdisciplinary approach using discriminant analysis of the morphometric characters, scanning electron microscopy, and molecular profile analysis. The data derived from the above mentioned approaches converge to significant similarity of the population under investigation with A. urmiana. The updated geographic distribution of the species, deriving from the present report, asks for additional contribution of other disciplines (e.g., avian dispersal of cysts, history of salt trade) to be finally clarified. At present we suggest that the punctuated geographic distribution of A. urmiana is probably linked to its low dispersal capability, and we suppose that its presence in two distant sites could be explained by historical human salt trade between Lake Urmia and the ancient port of Kimmerik, whose remains have been found in the present Lake Koyashskoe. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
68.
The vacuolar and epicuticular flavonoids and the volatiles of the leaves and parts of flower of P. spectabilis Tratt., an endemic species in the Italian Oriental Alps, were investigated. From a MeOH extract of the leaves two flavone glycosides, 8-C-β-glucopyranosylluteolin 7-O-α-arabinofuranoside (1) and 6-C-α-arabinofuranosylapigenin (2) were isolated, in addition to a flavone and three flavonols already known from species of Primula. From an EtOH extract of leaf exudates, 7,3',4'-tri-O-methylquercetin was obtained. The structures were elucidated on the basis of their 1D 1H- and 13C NMR data and 2D NMR techniques, as well as of HPLC-MS. The volatiles emitted by the leaves were mainly constituted by non-terpene derivatives, followed by comparable proportions of hemiterpens, oxygenated monoterpenes and sesquiterpene hydrocarbons. In flowers, monoterpene hydrocarbons were the most represented chemical class followed by non-terpene derivatives. Different proportions of compounds were found when individual parts of flowers were examined separately; calyx produced a greater proportion (approx. 49.5%) of non-terpenes as its volatile metabolites. P. spectabilis has glandular trichomes in the hyaline margins of the epidermal depressions, distributed on the adaxial leaf blade. Glandular hairs were also present on the corolla. Correlations of phytochemical data with the morphological features of leaf, flower and glandular hair are discussed, and a hypothesis is proposed on the ecological roles of the flavonoids and volatile compounds on the general fitness of the species and cross-pollination strategies. 相似文献
69.
Bellia F Vecchio G Cuzzocrea S Calabrese V Rizzarelli E 《Molecular aspects of medicine》2011,32(4-6):258-266
Carnosine (β-alanyl-L-histidine) is a natural dipeptide widely and abundantly distributed in excitable tissues of several animal tissues. Although its physiological role has not been completely understood yet, many beneficial actions have been attributed to carnosine, such as being an antioxidant, antiglycating and ion-chelating agent, a wound healing promoter and a free-radical scavenger. The role of carnosine in the neuroprotection of oxidative stress-driven disorders has been reviewed. The effects of carnosine have been extensively studied both in vivo and in vitro models of cerebral damages, such as neurodegenerative disorders and hypoxia-ischemia injuries. Beside the classical sacrificial agent, carnosine has been reevaluated as a molecular chaperon and an inducer of antioxidant systems in oxidative stress conditions. Thus, beneficial effects on most of the common biochemical events that characterize neurological disorders make carnosine a very promising molecule among all the endogenous compounds in the treatment and/or prevention of oxidative driven diseases. 相似文献
70.
Macchioni L Davidescu M Sciaccaluga M Marchetti C Migliorati G Coaccioli S Roberti R Corazzi L Castigli E 《Journal of bioenergetics and biomembranes》2011,43(5):507-518
Most cancer cells, including GL15 glioblastoma cells, rely on glycolysis for energy supply. The effect of antiglycolytic bromopyruvate
on respiratory parameters and viability of GL15 cells was investigated. Bromopyruvate caused Δψm and MTT collapse, ATP decrease, and cell viability loss without involving apoptotic or necrotic pathways. The autophagy marker
LC3-II was increased. Δψm decrease was accompanied by reactive oxygen species (ROS) increase and cytochrome c (cyt c) disappearance, suggesting a link
between free radical generation and intramitochondrial cyt c degradation. Indeed, the free radical inducer menadione caused
a decrease in cyt c that was reversed by N-acetylcysteine. Cyt c is tightly bound to the inner mitochondrial membrane in GL15
cells, which may confer protein peroxidase activity, resulting in auto-oxidation and protein targeting to degradation in the
presence of ROS. This process is directed towards impairment of the apoptotic cyt c cascade, although cells are committed
to die. 相似文献