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排序方式: 共有765条查询结果,搜索用时 15 毫秒
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José Maria Villela Pádua Kaio Olímpio Das Graças Dias Maria Marta Pastina João Cândido de Souza Valéria Aparecida Vieira Queiroz Rodrigo Veras da Costa Maria Beatriz Pereira da Silva Carlos Alexandre Gomes Ribeiro Claudia Teixeira Guimarães Salvador Alejandro Gezan Lauro José Moreira Guimarães 《Euphytica》2016,211(3):277-285
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Francesc Sardà Marta Coll Johanna J Heymans Konstantinos I Stergiou 《Fish and Fisheries》2015,16(1):175-180
Discards are the portion of animal and plant material in the catch that is dumped back at sea. The Common Fisheries Policy plan proposed by the European Commission for 2014–2020 presents a controversial goal: to enforce the landing of fishing discards as a measure to encourage their reduction. This historical and political decision will shape the future of the fishing exploitation in European Seas. Discards generated by European fleets are not negligible, and its reduction is an ecological, socioeconomical and moral imperative. However, it must be achieved through the reduction in discards at source and the promotion of selective and non‐destructive gears. We argue it is doubtful that this discard ban will result in an effective reduction of discards. The proposed measure may, in fact, negatively affect ecosystems at all levels of biological hierarchy by disregarding the Ecosystem‐Based Approach to Fisheries and the Precautionary Principle. It could negatively impact several species by increasing fishing mortality, also commercial species if discards are not accounted in the total allowable catch. Communities preying on discards will likely be affected. The role discards currently play in the energy turnover of current ecosystems will be modified and should be fully evaluated. The landing of discards will likely generate new markets of fishmeal due to the growing demands for marine living resources. The ban will require substantial public investment to deal with technical problems on board and to control and enforce. Therefore, this measure should be only implemented after rigorous scientific and technical studies have been developed. 相似文献
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Chiquinquirá Hontoria Rodolfo Velásquez Marta Benito Javier Almorox Ana Moliner 《Soil biology & biochemistry》2009,41(7):1583-1585
Glomalin, a substance produced by arbuscular mycorrhizal fungi, is reported to play a role in soil aggregation, but this role has been questioned in soils rich in calcium carbonate. We studied the relationship between aggregation stability and glomalin in a Haplic Calcisol comparing abandoned and active cultivation of olive groves. Abandonment was associated with increases in soil organic carbon, the percentage of water stable aggregates (WSA1-2mm), and easily extractable and total Bradford-reactive soil protein. WSA1-2mm was strongly positively correlated with both easily extractable and total Bradford-reactive soil protein. While easily extractable Bradford-reactive soil protein measured in both stable and unstable aggregates did not show any significant differences, Bradford-reactive soil protein was twice as high in stable than in unstable aggregates under both tillage and abandonment. Our results suggest that Bradford-reactive soil protein influences aggregate stability, even in soils with low organic matter and high calcium carbonate contents. However, more research is needed to elucidate the role of easily extractable Bradford-reactive soil protein in soil aggregation. 相似文献
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Eliseo Belda DVM PhD Francisco G Laredo DVM PhD CertVA Mayte Escobar DVM Amalia Agut DVM PhD Diplomate ECVDI Juliet C Mansel† BVM&S & Marta Soler DVM PhD CertVDI 《Veterinary anaesthesia and analgesia》2009,36(4):299-307
ObjectiveTo study the anaesthetic and cardiorespiratory effects of intramuscular (IM) administration of different combinations of romifidine and ketamine in cats.Study designProspective, randomized, cross-over experiment.AnimalsSeven healthy adult cats weighing (mean ± SD) 3.4 ± 0.7 kg and aged 4.6 ± 3.2 years.MethodsAnimals received romifidine 100 μg kg?1 with ketamine 7.5 (R100/K7.5) and 10 mg kg?1 (R100/K10), romifidine 200 μg kg?1 with ketamine 5 (R200/K5), 7.5 (R200/K7.5) and 10 mg kg?1 (R200/K10) by IM injection. The time required to perform orotracheal intubation (IT) was measured and the ease of intubation assessed. The onset of anaesthesia (OA), duration of anaesthesia (DA) and anaesthesia recovery times (AR) were measured. Analgesia and muscle relaxation scores were recorded every 5 minutes for 60 minutes after OA. Heart rate, systolic arterial pressure, arterial haemoglobin saturation, respiratory rate, end-tidal carbon dioxide and oesophageal temperature were also measured.ResultsThe IT, OA and DA were not significantly different between the treatments. The analgesia and muscle relaxation scores were similar between all treatments at most time points. The cardiorespiratory variables were not significantly different between the treatments in most cases. The adverse effects were dose dependent and similar to those previously described for other combinations of α2-agonists and ketamine.Conclusions and clinical relevanceAnaesthesia produced by the studied combinations of romifidine and ketamine may only be reliable when conducting brief and noninvasive procedures in cats. The OA times were slower and the DA shorter than those reported for other alpha-2 agonists combined with ketamine. A dose-related increase in the intensity of the anaesthetic effects could not be demonstrated in this study. 相似文献
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