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排序方式: 共有71条查询结果,搜索用时 312 毫秒
51.
Staffieri F Franchini D Carella GL Montanaro MG Valentini V Driessen B Grasso S Crovace A 《American journal of veterinary research》2007,68(9):925-931
OBJECTIVE: To compare the effect of 2 concentrations of oxygen in inspired gas (fraction of inspired oxygen [FIO(2)] 1.0 or 0.4) on pulmonary aeration and gas exchange in dogs during inhalation anesthesia. ANIMALS: 20 healthy dogs. PROCEDURES: Following administration of acepromazine and morphine, anesthesia was induced in each dog with thiopental and maintained with isoflurane in 100% oxygen (100% group; n = 10) or a mixture of 40% oxygen and air (40% group; 10). Dogs were placed in dorsal recumbency and were mechanically ventilated. After surgery, spiral computed tomography (CT) of the thorax was performed and PaO(2), PaCO(2), and the alveolar-arterial oxygen tension difference (P([A-a])O(2)) were assessed. The lung CT images were analyzed, and the extent of hyperinflated (-1,000 to -901 Hounsfield units [HUs]), normally aerated (-900 to -501 HUs), poorly aerated (-500 to -101 HUs), or nonaerated (-100 to +100 HUs) areas was determined. RESULTS: Compared with the 100% oxygen group, the normally aerated lung area was significantly greater and the poorly aerated and nonaerated areas were significantly smaller in the 40% oxygen group. The time to CT (duration of surgery) was similar in both groups. Although PaCO(2) was similar in both groups, PaO(2) and P((A-a))O(2) were significantly higher in the 100% oxygen group. In both groups, pulmonary atelectasis developed preferentially in caudal lung fields. CONCLUSION AND CLINICAL RELEVANCE: In isoflurane-anesthetized dogs, mechanical ventilation with 40% oxygen appeared to maintain significantly better lung aeration and gas exchange than ventilation with 100% oxygen. 相似文献
52.
Habluetzel A Carnevali F Lucantoni L Grana L Attili AR Archilei F Antonini M Valbonesi A Abbadessa V Esposito F van der Esch SA 《Veterinary parasitology》2007,144(3-4):328-337
Secondary metabolites present in the neem tree (Azadirachta indica A. Juss, Meliaceae), exhibit a wide range of biological activities in insects. However, few studies have been undertaken to assess the potential of neem products as insecticides for the control of ectoparasites of domestic animals. This study was undertaken to estimate the efficacy of Neem Azal, an azadirachtin-rich extract of neem seeds, in controlling Damalinia limbata (Phthiraptera) louse infestation of angora goats. The study was conducted on a fibre animal farm situated in Central Italy. Groups of 11-12 goats were treated with Neem Azal at an azadirachtin concentration of 650ppm or 125ppm, with Neguvon or were left untreated. Their louse burden was assessed fortnightly to monthly for 22 weeks. A reduction in louse densities of 76-96% was observed from week 2 to week 18 after treatment with the neem solution containing azadirachtin at a concentration of 650ppm. At the lower test concentration (125ppm) a reduction of 60-92% could be recorded from week 2 to week 14. Neem Azal was found to reduce the survival of both adult and nymph stages of D. limbata and to interfere with oviposition and oogenesis of female lice. A decrease in oviposition was observed in neem exposed female lice and the examination of their ovaries revealed morphological alterations in both vitellogenic and previtellogenic ovarioles at the follicular and germinal level. Since neem compounds target different life stages and physiological processes of D. limbata, the development of insecticide resistance by biting lice exposed to neem-based insecticides appears unlikely. For this reason and for its prolonged activity, which in principle allows angora goats to be protected for a large part of the mohair production cycle, neem-based insecticides may have a potential interest for mohair producing breeders. 相似文献
53.
Gabriella Tait Alberto Grassi Ferdinand Pfab Cristina M. Crava Daniel T. Dalton Roger Magarey Lino Ometto Silvia Vezzulli M. Valerio Rossi-Stacconi Angela Gottardello Andrea Pugliese Giuseppe Firrao Vaughn M. Walton Gianfranco Anfora 《Journal of pest science》2018,91(4):1213-1224
Drosophila suzukii (Diptera: Drosophilidae) is an invasive alien species devastating soft fruit crops in newly invaded territories. Little is known about the importance and potential of long-distance dispersal at a regional scale. The goal of this work is to investigate D. suzukii dispersal ability during different times of the season, and along an elevational gradient in a mountain valley in Trentino Province, Italy. We employed a mark–release–recapture strategy using protein markers. Flies were recaptured using fruit-baited traps. The protein-marked flies were positively identified using ELISA procedure. Additional microsatellite analyses were performed on D. suzukii collected during autumn at different elevations to characterize the population structure. Results suggest that a portion of the local D. suzukii population moves from low to high elevations during spring and summer and travels back to low elevations in autumn. Genetic analysis further revealed that samples collected during autumn at different elevations belong to the same population. These results show that D. suzukii are able to fly up to about 9000 m away from the marking point and that seasonal breezes likely facilitate long-distance movement. We suggest that these migrations have multiple functions for D. suzukii, including conferring the ability to exploit gradual changes of temperature, food, and ovipositional resources in spring and autumn, as well as to assist in the search for suitable overwintering sites in late autumn. Our findings help to unveil the complex ecology of D. suzukii in Italian mountainous regions and provide important clues for improving the efficacy of integrated pest management control techniques to combat this pest. 相似文献
54.
Roberta Esposito Serena Federico Marco Bertolino Valerio Zupo Maria Costantini 《Marine drugs》2022,20(4)
In the last decades, it has been demonstrated that marine organisms are a substantial source of bioactive compounds with possible biotechnological applications. Marine sponges, in particular those belonging to the class of Demospongiae, have been considered among the most interesting invertebrates for their biotechnological potential. In this review, particular attention is devoted to natural compounds/extracts isolated from Demospongiae and their associated microorganisms with important biological activities for pharmacological applications such as antiviral, anticancer, antifouling, antimicrobial, antiplasmodial, antifungal and antioxidant. The data here presented show that this class of sponges is an exciting source of compounds, which are worth developing into new drugs, such as avarol, a hydroquinone isolated from the marine sponge Disidea avara, which is used as an antitumor, antimicrobial and antiviral drug. 相似文献
55.
56.
Valerio Zupo Francesca Glaviano Marina Paolucci Nadia Ruocco Gianluca Polese Anna Di Cosmo Maria Costantini Mirko Mutalipassi 《Aquaculture Nutrition》2019,25(1):26-38
Sea urchin gonads are exploited both for gastronomic and scientific purposes; thus, the production of large and mature gonads is essential. Natural populations of the Mediterranean Sea urchin Paracentrotus lividus are subject to increasing fishing efforts, due to continuous intensification of consumptions. Aquaculture practices may represent an answer, but the availability of artificial feeds accelerating the production of high‐quality gonads in terms of size, taste, colour, firmness, maturity and viability of gametes is critical to boost the productions. The accessibility of cheap and effective feeds promoting the fattening of gonads and the quality of gametes is still a bottleneck slowing down the expansion of echinoculture practices. This investigation is aimed at enabling the development of this strategic sector, by comparing the dietetic effects of fresh foods and a commercial feed for aquaculture, to four newly formulated feeds. The protein contents of diets were strongly related to the GSIs. The abundance of fatty acids appeared inversely related to the viability of embryos and abnormalities of larvae. The features of an ideal diet for this sea urchin were defined, based on the results of experimental trials, and the need for increasing levels of plant‐derived proteins during the grow‐out period was demonstrated. 相似文献
57.
Sorrentino Roberto Pergamo Raffaella Battaglia Valerio Raimo Francesco Cermola Michele Lahoz Ernesto 《植物病害和植物保护杂志》2019,126(6):585-591
Journal of Plant Diseases and Protection - Symptoms of foot rot were observed on hemp (Cannabis sativa) plants in Campania region (Southern Italy) in 2018. The symptoms consisted of brownish areas... 相似文献
58.
Valerio Bartolino Francesco Colloca Lorna Taylor Gunnar Stefansson 《Fisheries Research》2011,107(1-3):75-83
An age-length structured model was built for European hake Merluccius merluccius in the central Mediterranean Sea using Gadget. This analytical framework allowed to integrate multiple sources of information, including fisheries-dependent and fisheries-independent data, collected at different scales and aggregation levels. The model includes the two main fisheries targeting hake in the area, the trawl and the gillnet fisheries, and account for differences in their selectivity and effort. Alternative models were used for testing different assumptions on recruitment and growth. The model is then used to predict the main trajectory of the stock during the next years and to evaluate the potential effects of implementing closed areas management scenarios in the hake nurseries as a specific tool to reduce fishing mortality on recruits. The modelling framework presented performed successfully also in a commercial landing data limited context, common for the Mediterranean. Our results provide statistical support for fast growth and multiple recruitment events assumptions. Including both these key features represent an unprecedented improvement of modelling hake population dynamics in the Mediterranean. We found that the reduction in the fishing effort that characterized the fisheries in the study area during the last few years, coupled with fast recovery abilities of the hake stock, has the potentiality to allow a moderate increase of the stock during the next years. Interestingly, our simulations show that the positive effects which might be expected from protecting hake nursery grounds are only marginally related to a reduction in hake recruits fishing mortality. Although our model relies on assumptions and surely represents an over-simplification of the real world, it still contributed to improve our understanding of the temporal dynamics of one of the most valuable fish stocks in the central Mediterranean. 相似文献
59.
Steven E. Beggs Massimiliano Cardinale Richard J. Gowen Valerio Bartolino 《Fisheries Oceanography》2014,23(1):54-64
How climatic variability and anthropogenic pressures interact to influence recruitment is a key factor in achieving sustainable resource management. However, the combined effects of these pressures can make it difficult to detect non‐stationary interactions or shifts in the relationships with recruitment. Here we examine the links between climate and Irish Sea cod recruitment during a period of declining spawning stock biomass (SSB). Specifically, we test for a shift in the relationship between recruitment, SSB and climate by comparing an additive (generalized additive model, GAM) and non‐additive threshold model (TGAM). The relationship between recruitment success, SSB and the climatic driver, sea surface temperature, was best described by the TGAM, with a threshold identified between recruitment and SSB at approximately 7900 t. The analysis suggests a threshold shift in the relationship between recruitment and SSB in Irish Sea cod, with cod recruitment being more sensitive to climatic variability during the recent low SSB regime. 相似文献
60.
Mirko Mutalipassi Gennaro Riccio Valerio Mazzella Christian Galasso Emanuele Somma Antonia Chiarore Donatella de Pascale Valerio Zupo 《Marine drugs》2021,19(4)
Cyanobacteria are a diversified phylum of nitrogen-fixing, photo-oxygenic bacteria able to colonize a wide array of environments. In addition to their fundamental role as diazotrophs, they produce a plethora of bioactive molecules, often as secondary metabolites, exhibiting various biological and ecological functions to be further investigated. Among all the identified species, cyanobacteria are capable to embrace symbiotic relationships in marine environments with organisms such as protozoans, macroalgae, seagrasses, and sponges, up to ascidians and other invertebrates. These symbioses have been demonstrated to dramatically change the cyanobacteria physiology, inducing the production of usually unexpressed bioactive molecules. Indeed, metabolic changes in cyanobacteria engaged in a symbiotic relationship are triggered by an exchange of infochemicals and activate silenced pathways. Drug discovery studies demonstrated that those molecules have interesting biotechnological perspectives. In this review, we explore the cyanobacterial symbioses in marine environments, considering them not only as diazotrophs but taking into consideration exchanges of infochemicals as well and emphasizing both the chemical ecology of relationship and the candidate biotechnological value for pharmaceutical and nutraceutical applications. 相似文献