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排序方式: 共有291条查询结果,搜索用时 15 毫秒
251.
Cortese L Pelagalli A Piantedosi D Mastellone V Di Loria A Lombardi P Ciaramella P Avallone L 《Veterinary journal (London, England : 1997)》2008,177(3):405-410
Thirty dogs naturally infected with Leishmania infantum were studied in order to determine the effects of treatment on haemostatic function. The animals were divided randomly into two treatment groups: Group 1 received meglumine antimoniate and allopurinol; Group 2 dogs were given the same treatment plus prednisone. Ten healthy animals were used as untreated controls. Clinical examination and determination of platelet aggregation, coagulation factors and biochemical parameters were undertaken before treatment and after 15, 30 and 60 days. A significant improvement in platelet aggregation was detected after 60 days in Group 1, but only after 15 days in Group 2. In both treated groups, platelet aggregation was lower than in the control group at the end of the study. The results suggest that prednisone may be a useful tool in the treatment of haemostatic disorders during canine leishmaniosis. The potential benefits and risks due to the use of corticosteroids in the treatment of leishmaniosis are discussed. 相似文献
252.
Imen Tarchoune Jamel Harrathi Pier Luigi Cioni Mokhtar Lachaâl Guido Flamini Zeineb Ouerghi 《植物养料与土壤学杂志》2013,176(5):748-755
The volatile compounds emitted by living leaves of basil (Ocimum basilicum L. cv. Genovese) plants under saline conditions were investigated by means of headspace–solid phase microextraction (HS‐SPME) and gas chromatography coupled with mass spectrometry (GC–MS). Furthermore, the composition of the essential oil obtained by hydrodistillation of the leaves was studied. Plants were grown for 15 d without salt or with an equimolar concentration of Na+ in the form of Na2SO4 (25 mM) and NaCl (50 mM), after which the growth, the essential oil, and the volatile constituents of the leaves were determined. Fifty‐four components were identified belonging to different chemical classes. Under control conditions, the essential oil was rich in linalool (45.9%), 1,8‐cineole (16.7%), eugenol (10.3%), trans‐α‐bergamotene, and epi‐α‐cadinol (4.9%). The main volatiles detected in the headspace of leaves of untreated basil plants were linalool (29.8%), followed by 1,8‐cineole (19.2%), trans‐α‐bergamotene (10.0%), and eugenol (7.0%). Under saline conditions, leaf growth was more depressed by 25 mM Na2SO4 than 50 mM NaCl, and essential oil concentration increased by 22% in the NaCl, but decreased by 18% in the Na2SO4 treatment, respectively. Both salts caused some changes in the essential oil and composition of volatile compounds. Most prominent was a strong negative correlation between eugenol and methyleugenol proportions, which may indicate an enhancement of the O‐methyltransferase activity. In comparison to the essential oil, the composition of volatiles showed some variations in their emission profile under both salts, the most important was an increase of eugenol. It is therefore concluded that the decrease of eugenol occurring in basil essential oil caused by both salts could be due to the enhancement of the eugenol O‐methyltransferase activity, an enzyme that accepts eugenol as substrate, generating methyl eugenol, and also to the increase of the eugenol emission as shown by the SPME profile. 相似文献
253.
Luigi Pistelli Clementina Sansone Arianna Smerilli Marco Festa Douglas M. Noonan Adriana Albini Christophe Brunet 《Marine drugs》2021,19(7)
Photochemoprevention can be a valuable approach to counteract the damaging effects of environmental stressors (e.g., UV radiations) on the skin. Pigments are bioactive molecules, greatly attractive for biotechnological purposes, and with promising applications for human health. In this context, marine microalgae are a valuable alternative and eco-sustainable source of pigments that still need to be taken advantage of. In this study, a comparative in vitro photochemopreventive effects of twenty marine pigments on carcinogenic melanoma model cell B16F0 from UV-induced injury was setup. Pigment modulation of the intracellular reactive oxygen species (ROS) concentration and extracellular release of nitric oxide (NO) was investigated. At the cell signaling level, interleukin 1-β (IL-1β) and matrix metallopeptidase 9 protein (MMP-9) protein expression was examined. These processes are known to be involved in the signaling pathway, from UV stress to cancer induction. Diatoxanthin resulted the best performing pigment in lowering MMP-9 levels and was able to strongly lower IL-1β. This study highlights the pronounced bioactivity of the exclusively aquatic carotenoid diatoxanthin, among the others. It is suggested increasing research efforts on this molecule, emphasizing that a deeper integration of plant ecophysiological studies into a biotechnological context could improve the exploration and exploitation of bioactive natural products. 相似文献
254.
Annalisa Vilasi Maria Chiara Monti Alessandra Tosco Simona De Marino Luigi Margarucci Raffaele Riccio Agostino Casapullo 《Marine drugs》2013,11(4):1288-1299
Secondary metabolites contained in marine organisms disclose diverse pharmacological activities, due to their intrinsic ability to recognize bio-macromolecules, which alter their expression and modulate their function. Thus, the identification of the cellular pathways affected by marine natural products is crucial to provide important functional information concerning their mechanism of action at the molecular level. Perthamide C, a marine sponge metabolite isolated from the polar extracts of Theonella swinhoei and endowed with a broad and interesting anti-inflammatory profile, was found in a previous study to specifically interact with heat shock protein-90 and glucose regulated protein-94, also disclosing the ability to reduce cisplatin-mediated apoptosis. In this paper, we evaluated the effect of this compound on the whole proteome of murine macrophages cells by two-dimensional DIGE proteomics. Thirty-three spots were found to be altered in expression by at least 1.6-fold and 29 proteins were identified by LC ESI-Q/TOF-MS. These proteins are involved in different processes, such as metabolism, structural stability, protein folding assistance and gene expression. Among them, perthamide C modulates the expression of several chaperones implicated in the folding of proteins correlated to apoptosis, such as Hsp90 and T-complexes, and in this context our data shed more light on the cellular effects and pathways altered by this marine cyclo-peptide. 相似文献
255.
Federica Rossi DMV SRV Massimo Vignoli DMV SRV Rossella Terragni DMV SPCAA Luigi Pozzr DMV Carlo Impallomeni DM Marina Magnani DM 《Veterinary radiology & ultrasound》2003,44(3):283-286
A 9-month-old neutered male cat was referred because of left forelimb lameness. Physical examination, laboratory analysis, and radiographic examination of the entire skeleton were performed. The radiographic diagnosis was bilateral radio-ulnar synostosis with secondary elbow malformation. A comparison between clinical and radiographic findings of the cat and those described in children affected by radio-ulnar synostosis is reported. Correlations and differences are discussed. 相似文献
256.
Identifying, managing and monitoring conflicts between forest biodiversity conservation and other human interests in Europe 总被引:3,自引:0,他引:3
Jari Niemel Juliette Young Didier Alard Miren Askasibar Klaus Henle Richard Johnson Mikko Kurttila Tor-Bjrn Larsson Simone Matouch Peter Nowicki Rosa Paiva Luigi Portoghesi Ren Smulders Alan Stevenson Urmas Tartes Allan Watt 《Forest Policy and Economics》2005,7(6):877-890
In this paper, circumstances where various human activities and interests clash with the conservation of forest biodiversity are examined, with particular focus on the drivers behind the conflicts. After identifying past and current human-related threats potentially leading to conflicts in forests, the paper will focus on conflict management and monitoring, with an emphasis on inclusionary stakeholder networks and a range of approaches towards sustainable land use. Three dimensions of conflicts are examined: substance (‘how things are’), procedure (‘how things are done’), and relationships (‘how people behave’). These relations will relate to three conflict management approaches: (1) technical, which may contribute to reduce or solve the conflict acting on the ‘substance’ dimension, (2) political, which may influence the ‘procedure’ dimension of the conflict establishing principles or rules, and (3) cultural, which may affect the ‘relationship’ dimension of the conflict. Finally, a general model of adaptive conflict management emphasising communication among the parties and a participatory approach that involves monitoring of the conflict resolution outcomes is proposed. The recognition that strong perceptions among stakeholders have the potential to aggravate conflicts is central to the concept of a inclusionary conflict management framework, improved communication between all stakeholders, and better awareness of the context of the conflicts is emphasised. 相似文献
257.
Gambuti A Strollo D Ugliano M Lecce L Moio L 《Journal of agricultural and food chemistry》2004,52(18):5747-5751
The concentrations of trans-resveratrol, (+)-catechin, (-)-epicatechin, and quercetin were evaluated by means of high-performance liquid chromatography-diode array detection in red wines obtained from Aglianico, Piedirosso, and Nerello Mascalese grapes. The trans-resveratrol and epicatechin concentrations did not differ significantly between experimental wines. The concentration of quercetin in Nerello Mascalese wines was more than twice that observed in Aglianico and Piedirosso wines. Nerello Mascalese wines also significantly differed from other wines in the (+)-catechin content, which was significantly higher than those found in the other two wines. During maceration, the maximum extraction of trans-resveratrol was reached after 12 days for Aglianico and Piedirosso, after which a decline was observed. On the contrary, in the case of Nerello Mascalese, the concentration of trans-resveratrol increased steadily throughout the whole maceration process. After 2 days of maceration, the maximum concentration of quercetin was observed in Aglianico must, whereas the maximum quercetin extraction was reached after 12 days for Piedirosso and 17 days for Nerello Mascalese. The maximum levels of (+)-catechin and (-)-epicatechin were generally observed after 12 days of maceration for all wines, although a decline of (-)-epicatechin occurred after maximum extraction in Aglianico and Piedirosso wines. Following marc pressing, a significant increase in the concentration of trans-resveratrol for Aglianico, (+)-catechin and (-)-epicatechin for Piedirosso, and (-)-epicatechin for Nerello Mascalese was observed. 相似文献
258.
What's in an index? Comparing the ecological information provided by two indices to assess the status of coralligenous reefs in the NW Mediterranean Sea
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259.
Baggenstoss J Poisson L Kaegi R Perren R Escher F 《Journal of agricultural and food chemistry》2008,56(14):5836-5846
The impact of time-temperature combinations of roasting processes on the kinetics of aroma formation in coffee was investigated. The development of 16 aroma compounds and the physical properties of coffee beans was followed in a commercial horizontal drum roasting process and in laboratory scale fluidizing-bed roasting processes at high temperature-short time and low temperature-long time conditions. All trials were run to an equal roast end point as defined by the lightness of coffee beans. In addition, the effect of excessive roasting on aroma composition was studied. Compared to low temperature-long time roasting, high temperature-short time roasting resulted in considerable differences in the physical properties and kinetics of aroma formation. Excessive roasting generally led to decreasing or stable amounts of volatile substances, except for hexanal, pyridine, and dimethyl trisulfide, whose concentrations continued to increase during over-roasting. When the drum roaster and the fluidizing bed roaster were operated in the so-called temperature profile mode, that is, along the identical development of coffee bean temperature over roasting time, the kinetics of aroma generation were similar in both processes. 相似文献
260.
Complementary conservation strategies for the genus Coffea: A case study of Mascarene Coffea species
Mohammad Ehsan Dulloo Luigi Guarino Florent Engelmann Nigel Maxted John H. Newbury Frank Attere Brian V. Ford-Lloyd 《Genetic Resources and Crop Evolution》1998,45(6):565-579
No single conservation technique can adequately conserve the full range of genetic diversity of a target species or genepool. To optimize the efficiency of germplasm conservation, a range of conservation techniques needs to be applied simultaneously. In this paper we review the progress made in the application of both in situ and ex situ complementary conservation strategies and techniques to the conservation of the genus Coffea and identify areas where more research work is required. Traditionally, Coffea species have been conserved ex situ as living plants in field genebanks due to their intermediate seed storage behaviour. However, progress made in the field of biotechnology in recent years have made it possible to envisage the use of in vitro, slow growth and cryopreservation for medium- and long-term conservation of Coffea germplasm, respectively. In situ conservation is also an important option for long-term conservation, but there are no genetic reserves specifically set up for conserving Coffea. Protected areas and managed reserves offer the best opportunities for conserving Coffea. A case study for Mascarene Coffea in Mauritius is presented and a strategy for their conservation is discussed. 相似文献