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61.
Reducing the level of infection of cereal heads caused by Fusarium and associated mycotoxin accumulation in grains is of a high priority in order to secure the yield, agronomic performance, and food and feed safety from field to table. Strategies to tackle the problem have been proposed at many levels, including greater knowledge of the biology of toxigenic fungi and of plant–pathogen interactions, monitoring activities which extend from the field to the end-products, pre-breeding, breeding and transgenesis to develop new resistant plant varieties, crop protection based on synthetic or natural molecules, biocontrol of fungal populations, the development and use of models that take into account the climatic conditions, and the adoption of technological protocols for reducing or inactivating mycotoxins. This review article highlights that the problem is very complex but that the scientific community continues to produce important knowledge and potential solutions.  相似文献   
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A global map of human impact on marine ecosystems   总被引:12,自引:0,他引:12  
The management and conservation of the world's oceans require synthesis of spatial data on the distribution and intensity of human activities and the overlap of their impacts on marine ecosystems. We developed an ecosystem-specific, multiscale spatial model to synthesize 17 global data sets of anthropogenic drivers of ecological change for 20 marine ecosystems. Our analysis indicates that no area is unaffected by human influence and that a large fraction (41%) is strongly affected by multiple drivers. However, large areas of relatively little human impact remain, particularly near the poles. The analytical process and resulting maps provide flexible tools for regional and global efforts to allocate conservation resources; to implement ecosystem-based management; and to inform marine spatial planning, education, and basic research.  相似文献   
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How to improve access to land and livestock production in synergy with ecosystem conservation? The paradigm occurring in natural grasslands of the Southern Brazilian Campos biome is used to illustrate the dilemma. This paper aims to contribute by addressing the technical bases being used by legislations concerning access to land and incentive to production and their consequences for natural grassland systems. Current policies have a production-oriented focus trying to promote livestock productivity by setting minimum stocking rates to be applied in grasslands. The unexpected results are overgrazing and reduction of natural grasslands, so the dilemma production versus conservation emerges. There is a need for adapting access to land legislations to the new environmental functions expected for natural grasslands, which warrant a conservation-oriented approach according to their multifunctional role. Integrated measures are proposed, which could be helpful in resolving the conflicting compromises regarding the inducement of production and the promotion of natural resources conservation.  相似文献   
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Plant Foods for Human Nutrition - Beetroot is a good source of natural food colorants given that it contains significant amount of betalain pigments. This study investigates the three-months...  相似文献   
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Lagovirus is an emerging genus of Caliciviridae, which includes the Rabbit Hemorrhagic Disease Virus (RHDV) of rabbits and the European brown hare syndrome virus (EBHSV) of hares that cause lethal hepatitis. In 2010, a new RHDV related virus (RHDV2) with a unique genetic and antigenic profile and lower virulence was identified in France in rabbits. Here we report the identification of RHDV2 as the cause in Sardinia of several outbreaks of acute hepatitis in rabbits and Cape hare (Lepus capensis mediterraneus). This is the first account of a lagovirus that causes fatal hepatitis in both rabbits and hares.  相似文献   
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Objective

To evaluate the effects of an alveolar recruitment maneuver (ARM) followed by 5 cmH2O positive end-expiratory pressure (PEEP) in dogs undergoing laparoscopy.

Study design

Prospective, randomized clinical study.

Animals

A group of 20 dogs undergoing laparoscopic ovariectomy.

Methods

Dogs were sedated with acepromazine and methadone intramuscularly; anesthesia was induced with propofol intravenously and maintained with inhaled isoflurane. The following baseline ventilatory setting (BVS) was administered: tidal volume of 12 mL kg–1, inspiratory to expiratory ratio of 1:2, inspiratory pause 25% of inspiratory time, no PEEP and a respiratory rate to maintain end-tidal carbon dioxide tension between 5.3 and 7.3 kPa. Then, 10 minutes after the pneumoperitoneum, 10 dogs (RM) underwent a sustained inflation ARM followed by BVS plus 5 cmH2O PEEP, while 10 dogs (NO-RM) were left with BVS throughout the procedure. Gas exchange and respiratory system mechanics were evaluated before the pneumoperitoneum (PPpre), before ARM (PP10), 30 minutes later (PP30) and 20 minutes after pneumoperitoneum discontinuation (PPpost20). Data were analyzed using anova (p < 0.05).

Results

The Fshunt at PP30 and PPpost20 was lower (p < 0.001) in the RM (2.3 ± 2.2 and 4.7 ± 3.7%) than in the NO-RM (5.2 ± 2.1 and 11.1 ± 5.2%), and PaO2 at PP30 and PPpost20 was higher (p < 0.001) in the RM (67.3 ± 4.2 and 60.1 ± 9.4 kPa) than in the NO-RM (50.2 ± 7.4 and 45.5 ± 11.1 kPa). Static compliance of the respiratory system at PP30 and PPpost20 was greater (p < 0.001) in the RM (2.4 ± 0.2 and 2.1 ± 0.4 mL cmH2O?1 kg–1) than in the NO-RM (0.9 ± 0.4 and 1.2 ± 0.2 mL cmH2O?1 kg–1).

Conclusions and clinical relevance

In dogs undergoing laparoscopy, ARM followed by 5 cmH2O PEEP improves gas exchange and respiratory system mechanics.  相似文献   
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