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排序方式: 共有490条查询结果,搜索用时 15 毫秒
1.
Alessandra Bertoli Anthea LoBue Luca Quattrini Stefania Sartini Beatrice Polini Sara Carpi Francesco Paolo Frontini Graziano Di Giuseppe Graziano Guella Paola Nieri Concettina La Motta 《Marine drugs》2022,20(11)
Euplotin C is a sesquiterpene of marine origin endowed with significant anti-microbial and anti-tumor properties. Despite the promising functional profile, its progress as a novel drug candidate has failed so far, due to its scarce solubility and poor stability in aqueous media, such as biological fluids. Therefore, overcoming these limits is an intriguing challenge for the scientific community. In this work, we synthesized β-cyclodextrin-based nanosponges and investigated their use as colloidal carriers for stably complex euplotin C. Results obtained proved the ability of the carrier to include the natural compound, showing remarkable values of both loading efficiency and capacity. Moreover, it also allowed us to preserve the chemical structure of the loaded compound, which was recovered unaltered once extracted from the complex. Therefore, the use of β-cyclodextrin-based nanosponges represents a viable option to vehiculate euplotin C, thus opening up its possible use as pharmacologically active compound. 相似文献
2.
Pablo M. Vergara Luis O. Meneses Audrey A. Grez Madelaine S. Quiroz Gerardo E. Soto Christian G. Pérez-Hernández Paola A. Diaz Ingo J. Hahn Andrés Fierro 《Landscape Ecology》2017,32(2):279-293
Context
Interactions between landscape-scale processes and fine-grained habitat heterogeneity are usually invoked to explain species occupancy in fragmented landscapes. In variegated landscapes, however, organisms face continuous variation in micro-habitat features, which makes necessary to consider ecologically meaningful estimates of habitat quality at different spatial scales.Objectives
We evaluated the spatial scales at which forest cover and tree quality make the greatest contribution to the occupancy of the long-horned beetle Microplophorus magellanicus (Coleoptera: Cerambycidae) in a variegated forest landscape.Methods
We used averaged data of tree quality (as derived from remote sensing estimates of the decay stage of single trees) and spatially independent pheromone-baited traps to model the occurrence probability as a function of multiple cross-scale combinations between forest cover and tree quality (with scales ranging between 50 and 400 m).Results
Model support and performance increased monotonically with the increasing scale at which tree quality was measured. Forest cover was not significant, and did not exhibit scale-specific effects on the occurrence probability of M. magellanicus. The interactive effect between tree quality and forest cover was stronger than the independent (additive) effects of tree quality and particularly forest cover. Significant interactions included tree quality measured at spatial scales ≥200 m, but cross-scale interactions occurred only in four of the seven best-supported models.Conclusions
M. magellanicus respond to the high-quality trees available in the landscape rather than to the amount of forest per se. Conservation of viable metapopulations of M. magellanicus should consider the quality of trees at spatial scales >200 m.3.
Cairoli P Pieraccini S Sironi M Morelli CF Speranza G Manitto P 《Journal of agricultural and food chemistry》2008,56(3):1043-1050
A number of N2-alkyl and N2-acyl derivatives of guanosine 5'-phosphate (GMP) have been synthesized and tested for their synergistic effect with monosodium L-glutamate (MSG), the prototypical substance imparting umami taste to savory-based foods. Capacities to enhance the taste intensity of MSG (gamma values) were estimated through subjective comparisons of MSG/nucleotide mixtures in water with appropriate solutions of MSG alone. Assuming beta = gamma[nucleotide]/gamma[IMP], beta values of the N2-substituted GMPs were found in the range 1.2-5.7. Such values appear to be related to the chain length of the substituent in the 2-position of the purine nucleus and dependent on the replacement of a CH 2 group with an S atom and/or with an alpha-CO group. These findings indicate that the exocyclic NHR group of the guanine moiety is actively implicated in the synergism between GMP derivatives and MSG. Theoretical calculations suggest that an anti conformation is probably assumed by ribonucleotide molecules interacting with umami receptors. 相似文献
4.
Domitilla Pulcini Tommaso Russo Paola Reale Alexia Massa‐Gallucci Grace Brennan Stefano Cataudella 《Aquaculture Research》2014,45(3):397-409
Prolonged exposure to captive conditions has led to the development of a rainbow trout ‘farmed’ phenotype, which is different from that of wild trout. Selection for desirable productive traits in hatcheries has resulted in the development of some morphological traits that are maladaptive in nature. The recent development of organic aquaculture, guided by the well‐being of the fish, could potentially produce a new farmed phenotype that would be more adaptive in nature. In this study, rainbow trout reared in intensive and organic farms were compared by means of shape analysis, to detect patterns of shape variation associated with rearing environment. The results of this study highlight a significant effect of the rearing method on rainbow trout shape: organically reared trout showed a higher body profile, in particular in the head and trunk regions, shorter median fins and a deeper caudal peduncle. A combined effect of density and habitat complexity could have contributed to the observed shape differences: in organic rearing systems, lower densities and steady water could increase territoriality and aggressive interactions, promoting body designs more functional in rapid attacks and escapes. 相似文献
5.
Paola Marticorena Leonel Gonzalez Carlos Riquelme Fernando Silva Aciares 《Aquaculture Research》2020,51(9):3609-3622
The present study evaluated the effects of five bacterial isolates from the microalga Muriellopsis sp. on the microalgal biomass concentration (g/L), specific growth rate (K), photosynthetic quantum yield (QY), non‐photochemical quenching (NPQ), maximum relative electron transport rates (rETR max) and levels of nutritional components such as carbohydrates, lipids, proteins and carotenoids in Muriellopsis sp. cultivated in seawater under indoor and outdoor conditions. The bacterial strains were Microbacterium sp. Dom 1; Pseudomonas sp. Dom2; Microbacterium sp. Dom 3; Rhizobium sp. Dom 4; and Dietzia sp. Dom 5, as well as the Pseudoalteromonas sp. (SLP1), a bacterium known to promote the growth of microalgae. At the laboratory level, inoculation of the strains SLP1, Dom 1, Dom 3 and Dom 5 resulted in higher specific growth rates and biomass of the microalga. Subsequently, the best results were obtained with a combination of the selected bacterial strains (Dom1, Dom 3, Dom5 and SLP1) under outdoor culture conditions improved the biomass, proteins, carbohydrates and total carotenoids in 22.12%, 48.28%, 19,25% and 48.27%, respectively, compared to cultures without the incorporation of the selected bacteria (control), while no effects were observed on the photosynthetic parameters. Thus, it was demonstrated that positive associations of the selected bacterial strains played an important role in the production of Muriellopsis sp. acclimatized to grow in seawater. This is of crucial importance, especially in desert areas, where solar radiation is high and freshwater is a limited resource. 相似文献
6.
Woo JC Roccabianca P van Stijn A Moore PF 《Veterinary immunology and immunopathology》2002,85(1-2):9-22
The characteristics of a feline homologue of the alphaE integrin (CD103), defined by two murine monoclonal antibodies, Fe7.1B8 (IgG1) and Fe7.2D8 (IgG1), are described. These antibodies recognized 75% of intra-epithelial (range 59-88%) and 40% of lamina proprial (range 28-46%) T cells of the intestinal mucosal tissue of the small intestine in contrast with approximately 2% of peripheral blood lymphocytes. Both antibodies immunoprecipitated a 180 kDa protein from biotinylated feline intra-epithelial mucosal leukocytes consistent with the alphaE integrin subunit in conjunction with a 120 kDa protein consistent with the beta7 subunit. The nucleotide sequence of feline alphaE integrin, generated from molecular cloning of the feline alphaE encoding cDNA, is also reported. This feline molecule shares 72% sequence homology with human and 69% homology with murine and rat counterparts. Homology includes the presence of an X (extra) domain, that appears unique to alphaE molecules as described for human, rat and mouse, as well as areas of homology common to other alpha integrins. Of note is a typical I (inserted) domain, the presence of seven repeat regions, and highly conserved sequences in the cytoplasmic tail. Transfection studies demonstrated that both antibodies recognized an extracellular component which encompassed the X and I domains of the cloned alphaE integrin subunit. These studies demonstrate that the pattern of tissue distribution, biochemical characteristics, and cDNA sequence of the feline alphaE integrin subunit are largely similar to that described for other species. 相似文献
7.
Zizzadoro C Belloli C Badino P Ormas P 《Veterinary immunology and immunopathology》2002,89(1-2):99-104
A method for the separation of pure and viable lymphocytes and granulocytes from the same blood sample in horses was reported. By centrifuging equine heparinized blood at 100 xg for 10 min at room temperature (r.t.), the resulting supernatant plasma was an almost pure (97.71 +/- 0.30%; n = 15) suspension of highly viable (98.72 +/- 0.28%) lymphocytes. When sodium citrate was used as an anticoagulant, lymphocyte suspensions collected in the same manner showed lower purity (87.89 +/- 1.59%; n = 9) and higher yields (56.56 +/- 3.89%, n = 9 versus 36.11 +/- 2.23%, n = 15). Where needed, a further centrifugation at 250 xg for 3 min (r.t.) of heparinized lymphocyte preparations removed an average of 87.39% (n = 15) contaminating platelets. A suspension of 85.96 +/- 2.20% pure granulocytes (93.23 +/- 1.74% neutrophils; n = 14) with minimal contamination by erythrocytes and high viability (93.11 +/- 1.26%) was obtained by performing a flash red blood cell lysis on the white-greyish layer resulting from the centrifugation of the heparinized blood samples. Among the several methods available, the procedure described herein is easy, rapid, cheap and reproducible. 相似文献
8.
Poli A Abramo F Barsotti P Leva S Gramiccia M Ludovisi A Mancianti F 《Veterinary parasitology》2002,106(3):181-191
A case of leishmaniosis in domestic cats (Felis catus domesticus) is described. The subject showed a nodular lesion on the eyelid. The diagnosis was achieved by serological, parasitological, and light and electron microscopic investigations. By molecular techniques the aetiological agent was identified as belonging to Leishmania infantum, the species implicated in human and canine leishmaniosis in southern Europe. A preliminary study on the prevalence of asymptomatic feline leishmaniosis, performed in the areas where the infected cat was identified, revealed a low seroprevalence of infection: only 1 (0.9%) of the 110 cat sera examined by indirect fluorescent antibody test was positive for anti-Leishmania antibodies. Because clinical signs in feline leishmaniosis are unspecific and similar to those observed in other diseases commonly found in this species, leishmaniosis must be added to the differential diagnosis by feline veterinary practitioners and adequate serologic and histopathologic investigations must be performed in endemic areas. 相似文献
9.
10.
Assessment of coagulation utilizing thromboelastometry in dogs undergoing orthopedic surgery 下载免费PDF全文
Barbara Bruno DVM Cristiana Maurella DVM Sara Falco DVM Alberto Tarducci DVM Renato Zanatta DVM PhD Paola Gianella DVM PhD DACVIM Antonio D'Angelo DVM PhD DECVN DECBHM Lisa Piras DVM PhD Andrea Di Bella DVM MRCVS Antonio Borrelli DVM PhD MS 《Journal of Veterinary Emergency and Critical Care》2015,25(3):358-363