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排序方式: 共有144条查询结果,搜索用时 218 毫秒
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Dumontet S Krovacek K Svenson SB Pasquale V Baloda SB Figliuolo G 《Comparative immunology, microbiology and infectious diseases》2000,23(1):53-72
A survey was undertaken to examine sea water and sediment for the presence of Vibrio and Aeromonas spp. along approximately 900 km of coast in Southern Italy during early and late summer. A quantitative analysis was also done to evaluate the water fecal contamination at the stations examined. The results indicate that all the investigated areas were submitted to a wide spatial fluctuation of fecal contamination and that Vibrio and Aeromonas spp. were present in both high and low fecal-contaminated stations. Sixty two percent of the investigated samples were positive for Aeromonas spp., while 42% of samples were positive for Vibrio spp. It was interesting to note that 38% of the positive stations for both Aeromonas and Vibrio spp. showed a fecal coliform contamination of water at < 10(2) cells 100 ml(-1). Thus, these findings support the hypothesis that the bacterial indicators (such as fecal coliforms) do not always satisfactorily reflect the hygienic quality of water. The presence of Vibrionaceae on copepods was also investigated. Copepods were sampled at a station located inside the harbour of the city of Naples and were found contaminated by V. cholerae non-O1, V. alginolyticus, V. fluvialis and A. caviae. Furthermore, the antibiotic resistance patterns of isolated bacteria showed the presence of a number of resistant strains among the isolates. In order to discriminate the isolates on the basis of their biochemical profiles and/or antibiotic resistance patterns, cluster analysis was carried out which showed that no unique assay could fully discern these isolates. However, the best discrimination resulted from complete pattern profile based on both biochemical profiles and antibiotic resistance patterns. 相似文献
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Pasquale Saldarelli Adib Rowhani Geoffrey Routh Angelantonio Minafra Michele Digiaro 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(9):945-950
RT-PCR with degenerate primers was used for the screening of the genome of some members of the Closterovirus, Vitivirus and Trichovirus genera. Two sets of primers, targeted to conserved sequences of the heat shock protein 70 homologue of closteroviruses or to the RNA dependent RNA polymerase genes of tricho- and vitiviruses, amplified the expected fragments from total RNA extracts or double-stranded RNAs of infected plants. Amplified cDNAs were cloned, sequenced and phylogenetically analyzed. Results support the allocation of grapevine viruses A, B, D and heracleum latent virus (HLV) in the genus Vitivirus, whereas, the detection of a HSP70 homologue in grapevine leafroll-associated viruses agrees with their assignment in the genus Closterovirus. The use of degenerate primers for the identification of grapevine viruses belonging to Vitivirus and Closterovirus genera is envisaged. 相似文献
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Two ethanolic propolis extracts (EPE) with and without the caffeic acid phenethyl ester (CAPE), CAPE and galangin (major components of propolis) were investigated for anti-inflammatory activity in rats using carrageenin foot oedema, carrageenin pleurisy and adjuvant arthritis. In our experiments, EPE with CAPE and CAPE alone significantly inhibited carrageenin oedema, carrageenin pleurisy and adjuvant arthritis. In contrast EPE without CAPE and galangin did not exhibit anti-inflammatory effects in acute and chronic inflammation. These results suggest that the anti-inflammatory activity of propolis is due to CAPE. 相似文献
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Assessment of coagulation utilizing thromboelastometry in dogs undergoing orthopedic surgery 下载免费PDF全文
Barbara Bruno DVM Cristiana Maurella DVM Sara Falco DVM Alberto Tarducci DVM Renato Zanatta DVM PhD Paola Gianella DVM PhD DACVIM Antonio D'Angelo DVM PhD DECVN DECBHM Lisa Piras DVM PhD Andrea Di Bella DVM MRCVS Antonio Borrelli DVM PhD MS 《Journal of Veterinary Emergency and Critical Care》2015,25(3):358-363
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A systematic and quantitative approach to improve water use efficiency in agriculture 总被引:6,自引:2,他引:4
As the competition for the finite water resources on earth increases due to growth in population and affluence, agriculture
is faced with intensifying pressure to improve the efficiency of water used for food production. The causes for the relatively
low water use efficiency in agriculture are numerous and complex, including environmental, biological, engineering, management,
social, and economic facets. The complexity of the problem, with its myriads of local variations, requires a comprehensive
conceptual framework of the underlying physical and biological processes as the basis to analyze the existing situation and
quantify the efficiencies, and to plan and execute improvements. This paper proposes such a framework, based on the simple
fact that the overall efficiency of any process consisting of a chain of sequential step is the product of the efficiency
(i.e., output/input ratio) of its individual component steps. In most cases of water use, a number of process chains, both
branching and merging, are involved. Means to integrate the diverging and converging chains are developed and presented as
equations. Upscaling from fields to regions and beyond are discussed. This chain of efficiencies approach is general and can
be applied to any process composed of chains of sequential steps. Here the framework is used to analyze the systems of irrigated
and dryland crop production, and animal production on rangeland. Range of plausible efficiencies of each step is presented
as tables, with values separately for the poor and for the good situation of circumstances, management and technology. Causes
of the differences in efficiency of each step, going from water delivery to soil water extraction, transpiration, photosynthesis,
and conversion to crop biomass and yield, and to animal product are briefly discussed. Sample calculations are made to demonstrate
how modest differences in the efficiencies of the component steps are manifested as large to huge differences in the overall
efficiency. Based on an equation quantifying the impact of changes in efficiency of component steps on the overall efficiency,
it is concluded that generally, it is more effective to made modest improvements in several or more steps than to concentrate
efforts to improve one or two steps. Hence, improvement efforts should be systematic and not overly concentrated on one or
two components. The potential use of the same equation as the point of departure to optimize the allocation of economic resource
among the component steps to maximize the improvement in the overall water use efficiency is elaborated on. The chain of efficiencies
framework provides the means to examine the current levels of efficiency along the pathways of agricultural water use, to
analyze where inefficiencies lie by comparing with the range of known efficiency values in the tables presented, to assess
the potential improvements that may be achieved in various parts and their impact on the overall efficiency, and to aid in
the optimal allocation of resources for improvements.
相似文献
Theodore C. HsiaoEmail: |
9.
Antonino Caminiti Marcello Sala Valentina Panetta Sabrina Battisti Roberta Meoli Pasquale Rombolà Valentina Spallucci Claudia Eleni Paola Scaramozzino 《Preventive veterinary medicine》2014
In most European countries, registration and identification of dogs is compulsory. In Italy, the national dog registry is composed of regional dog registries. Although dog registries have been established for many years, the issue related to completeness of data has not been addressed so far. The objective of this study was twofold: first to assess the completeness of data of the dog registry through telephone interview of a sample of dog owners drawn from the dog registry, then to estimate the total owned dog population in 4 boroughs of Rome. For the second objective, a capture–recapture method was applied using data from the dog registry and data from a face-to-face questionnaire submitted to people waiting in the sitting room of 5 points of access for booking and payment of primary and specialist care. Different scenarios are proposed to verify the assumptions of the estimation procedure and potential biases are discussed. The completeness of data of the dog registry was 88.9% (95% CI: 85.8–91.9%) and the owned-dog population was estimated at 26,244 dogs (95% CI: 24,110–28,383). The dog registry is an important source of information especially when it is properly updated and completeness of data is known. 相似文献
10.
Maria Adamo Cristina Tarantino Valeria Tomaselli Vasiliki Kosmidou Zisis Petrou Ioannis Manakos Richard M. Lucas Caspar A. Mücher Giuseppe Veronico Carmela Marangi Vito De Pasquale Palma Blonda 《Landscape Ecology》2014,29(6):1045-1067
Monitoring biodiversity at the level of habitats and landscape is becoming widespread in Europe and elsewhere as countries establish international and national habitat conservation policies and monitoring systems. Earth Observation (EO) data offers a potential solution to long-term biodiversity monitoring through direct mapping of habitats or by integrating Land Cover/Use (LC/LU) maps with contextual spatial information and in situ data. Therefore, it appears necessary to develop an automatic/semi-automatic translation framework of LC/LU classes to habitat classes, but also challenging due to discrepancies in domain definitions. In the context of the FP7 BIO_SOS (www.biosos.eu) project, the authors demonstrated the feasibility of the Food and Agricultural Organization Land Cover Classification System (LCCS) taxonomy to habitat class translation. They also developed a framework to automatically translate LCCS classes into the recently proposed General Habitat Categories classification system, able to provide an exhaustive typology of habitat types, ranging from natural ecosystems to urban areas around the globe. However discrepancies in terminology, plant height criteria and basic principles between the two mapping domains inducing a number of one-to-many and many-to-many relations were identified, revealing the need of additional ecological expert knowledge to resolve the ambiguities. This paper illustrates how class phenology, class topological arrangement in the landscape, class spectral signature from multi-temporal Very High spatial Resolution (VHR) satellite imagery and plant height measurements can be used to resolve such ambiguities. Concerning plant height, this paper also compares the mapping results obtained by using accurate values extracted from LIght Detection And Ranging (LIDAR) data and by exploiting EO data texture features (i.e. entropy) as a proxy of plant height information, when LIDAR data are not available. An application for two Natura 2000 coastal sites in Southern Italy is discussed. 相似文献