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排序方式: 共有680条查询结果,搜索用时 630 毫秒
651.
Raquel Snchez‐Cspedes Paolo Accornero Silvia Miretti Eugenio Martignani Francesca Gattino Lorella Maniscalco Cecilia Gola Selina Iussich Marina Martano Emanuela Morello Paolo Buracco Luca Aresu Raffaella De Maria 《Veterinary and comparative oncology》2020,18(1):117-127
Canine osteosarcoma (OSA) is the most common primary malignant bone tumour in dogs, and it has a high metastatic rate and poor prognosis. Toceranib phosphate (TOC; Palladia, Zoetis) is a veterinary tyrosine kinase inhibitor that selectively inhibits VEGFR‐2, PDGFRs and c‐Kit, but its efficacy is not yet fully understood in the treatment of canine OSA. Here, we evaluated the functional effects of TOC on six OSA cell lines by transwell, wound healing and colony formation assays. Subsequently, two cell lines (Wall and Penny) were selected and were inoculated in mice by intrafemoral injection to develop an orthotopic xenograft model of canine OSA. For each cell line, 30 mice were xenografted; half of them were used as controls, and the other half were treated with TOC at 40 mg/kg body weight for 20 days. TOC inhibited cell growth of all cell lines, but reduced invasion and migration was only observed in Penny and Wall cell lines. In mice engrafted with Penny cells and subjected to TOC treatment, decreased tumour growth was observed, and PDGFRs and c‐Kit mRNA were downregulated. Immunohistochemical analyses demonstrated a significant reduction of Ki67 staining in treated mice when compared to controls. The results obtained here demonstrate that TOC is able to slightly inhibit cell growth in vitro, while its effect is evident only in a Penny cell xenograft model, in which TOC significantly reduced tumour size and the Ki67 index without modifying apoptosis markers. 相似文献
652.
Lorenz RD Stiles BW Kirk RL Allison MD Del Marmo PP Iess L Lunine JI Ostro SJ Hensley S 《Science (New York, N.Y.)》2008,319(5870):1649-1651
Cassini radar observations of Saturn's moon Titan over several years show that its rotational period is changing and is different from its orbital period. The present-day rotation period difference from synchronous spin leads to a shift of approximately 0.36 degrees per year in apparent longitude and is consistent with seasonal exchange of angular momentum between the surface and Titan's dense superrotating atmosphere, but only if Titan's crust is decoupled from the core by an internal water ocean like that on Europa. 相似文献
653.
654.
Kristina Brataševec Branka Mozetič Vodopivec Marko Petek Paolo Sivilotti 《植物养料与土壤学杂志》2015,178(6):868-877
The phenolic composition of white grapes is important since browning reactions may dramatically compromise the overall quality of musts and wines. Only few scientific contributions are available, which investigated how fertilization can influence this class of compounds. Thus, the aim of this work was to examine the effects of NPK soil fertilization coupled with soil or foliar applications of Mg, Fe, and Zn on the concentrations of K, Mg, Fe, and Zn of grape berries and leaf petioles of potted Rebula grapevines (Vitis vinifera L.), also revealing the change of hydroxycinnamic acids in grape juice. The results obtained over the three‐year study (2009–2011) showed that NPK fertilization positively affected K and Zn concentrations of petioles and grape berries, and negatively Mg. In addition, K (synergistic) and Mg (antagonistic) had an influence on Zn uptake. Our findings suggest that the supply of NPK was profitable for a reduction of trans‐caftaric acid in grape juice, while only few differences were observed with further application of nutrients. 相似文献
655.
Aiello A Fattorusso E Imperatore C Irace C Luciano P Menna M Santamaria R Vitalone R 《Marine drugs》2011,9(6):1157-1165
Chemical analysis of the Mediterranean ascidian Polyandrocarpa zorritensis (Van Name 1931) resulted in the isolation of a series of molecules including two monoindole alkaloids, 3-indolylglyoxylic acid (3) and its methyl ester (4), 4-hydroxy-3-methoxyphenylglyoxylic acid methyl ester (1) and a new alkaloid we named zorrimidazolone (2). The structure of the novel compound 2 has been elucidated by spectroscopic analysis and bioactivity of all compounds has been investigated. Zorrimidazolone (2) showed a modest cytotoxic activity against C6 rat glioma cell line. 相似文献
656.
Marcello Duranti Paolo Cerletti 《Plant foods for human nutrition (Dordrecht, Netherlands)》1983,33(2-3):135-138
All the main globulins in the seeds ofLupinus Albus are oligomeric glycoproteins. Legumins (33%) consist of two similar protein molecules which contain protomers linked by disulphide bridges. They result from a partial proteolytic breakdown of an original polypeptide chain. Vicilins (44%) consist of four similar protein molecules with several protomers linked together by non-covalent bonds. Globulin 1 (6%) has a native M.W. of 199 kd and is formed by four 45.0 kd subunits consisting of two smaller protomers (28.0 and 16.0 kd) linked by -S-S- bonds. Globulin 9b (12.5%) has the lowest M.W. (44.0 kd) and is made up of three protomers, two of which are linked by disulphide bonds. 相似文献
657.
Paolo Casale Amedeo Ciccocioppo Giulia Vagnoli Alessandro Rigoli Daniela Freggi Livia Tolve Paolo Luschi 《水产资源保护:海洋与淡水生态系统》2020,30(1):123-130
- Spatio‐temporal distribution is fundamental information for species of conservation concern, like sea turtles, that are threatened by anthropogenic activities at sea such as fishing. While coarse‐scale distribution information is available for several sea turtle populations, fine‐scale distribution informing on hot‐spot areas for spatial management is more difficult to obtain.
- Here a citizen science approach involving tourism boats was undertaken to investigate the spatio‐temporal distribution of the loggerhead sea turtle (Caretta caretta) in the Pelagie Archipelago, located in a major foraging area for this species in the Mediterranean and where high fishing‐induced mortality occurs. The study was designed to provide data of absence and total sampling effort, commonly under‐reported in citizen science studies, allowing comparison among zones and periods. This was complemented by reports from fishing vessels.
- Tourism boats reported 584 loggerhead turtle sightings during 1718 daily trips and fishing vessels reported 280 loggerhead turtles captured during 1040 fishing days. The results indicate a strong heterogeneous distribution in the Archipelago, with a low turtle occurrence around the main island, Lampedusa, where the highest human presence and activity occur. This may represent rare evidence of displacement behaviour of turtles that is worth further investigation. This also suggests that the current small marine protected area around Lampedusa has a low conservation impact. Zones with higher loggerhead turtle occurrence appear to be in the south and the west parts of the Archipelago, suggesting that spatial management would be possible when relatively small hot‐spots have been identified through specific surveys.
- This study shows the potential of citizen science for providing preliminary information to guide more demanding and specific investigations. Such an approach may tremendously and rapidly improve the current knowledge on fine‐scale sea turtle distribution in regions with a great extension of coastlines and intensive tourist activities, such as the Mediterranean.
658.
Cravero Diego Martignani EugenioMiretti Silvia Macchi ElisabettaAccornero Paolo Baratta Mario 《Research in veterinary science》2014
The detection and characterization of bovine mammary stem cells may give a better understanding of the cyclic characteristic of mammary gland development. In turn, this could potentially offer techniques to manipulate lactation yield and for regenerative medicine. We previously demonstrated that adult stem cells reside in the bovine mammary gland and possess an intrinsic regenerative potential. In vitro maintenance and expansion of this primitive population is a challenging task that could make easier the study of adult mammary stem cells. The aim of this study is to investigate this possibility. Different subpopulations of mammary epithelial cells emerge when they are cultured in two defined culture conditions. Specific cell differentiation markers as cytokeratin 18 (CK18) and cytokeratin 14 (CK14) were expressed with significant differences according to culture conditions. Vimentin, a well-known fibroblast marker was observed to increase significantly (P < 0.5) only after day 20. In both conditions, after prolonged culture (25 days) a subset of cells still retained regenerative capabilities. These cells were able to form organized pseudo-alveoli when transplanted in immunodeficient mice as shown by the expression of cytokeratin 14 (CK14), cytokeratin 18 (CK18), p63 (a mammary basal cell layer marker) and Epithelial Cell Adhesion Molecule (EpCAM). We also were able to observe the presence of milk proteins signal in these regenerated structures, which is a specific marker of functional mammary alveoli. Progenitor content was also analyzed in vitro through Colony-Forming Cell (CFC) assays with no substantial differences among culture conditions and time points. These results demonstrate that long-term culture of a multipotent cell subpopulation with intrinsic regenerative potential is possible. 相似文献
659.
660.
Edoardo PETRUCCO TOFFOLO Daniel ZOVI Chiara PERIN Paolo PAOLUCCI Alain ROQUES Andrea BATTISTI Helmuth HORVATH 《Integrative zoology》2014,9(3):320-327
Larvae of the processionary moths of the Palaearctic region bear urticating setae that are released against vertebrate predators, especially insectivorous birds. A few species are pests of forest and urban trees and, consequently, may threaten human and animal health during outbreaks, causing dermatitis, conjunctivitis and respiratory distress. Although some studies provide detailed information about the setae, particularly those of the pine processionary moth Thaumetopoea pityocampa, there is little knowledge on the morphological traits of the setae and their release by the larvae. In the present study we identify major traits of the setae of 3 species of processionary moth, T. pityocampa, T. pinivora and T. processionea, which are potentially helpful in the understanding of setae dynamics in the environment: (i) diameter and length of setae and (ii) analysis of dynamical properties of the setae in the airborne state. Setae are highly variable in size, with bimodal distribution in T. pityocampa and T. pinivora; in these 2 species, short and long setae are interspersed within the integument fields where they occur. The difference in the seta size has important consequences in dispersion, as smaller setae can spread 5 times further than their bigger counterparts. This information is relevant for a full understanding of the defensive importance of larval setae against natural enemies of the processionary moths, as well for elucidating the importance of the processionary setae as air pollutants, both close to the infested trees and at longer distances. 相似文献