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排序方式: 共有222条查询结果,搜索用时 31 毫秒
1.
Flavio A.V. Freitag Dorli da S. Amora Eloisa Muehlbauer Peterson T. Dornbusch Marcello Machado Fabiano Montiani-Ferreira Edison L. Prisco Farias Alexander Valverde Juan Carlos Duque Moreno 《Veterinary anaesthesia and analgesia》2021,48(4):596-602
ObjectiveTo describe and evaluate an ultrasound-guided modified subcostal approach for the transversus abdominis plane (TAP) block in horse cadavers in lateral or dorsal recumbency.Study designProspective, experimental cadaveric study.AnimalsStudy of one preserved foal and eight fresh adult horse cadavers.MethodsThe lateral and ventral abdominal wall of a preserved cadaver was dissected to identify the muscles and nerves. A unilateral standard TAP block technique was performed (60 mL of methylene blue dye–bupivacaine) on a fresh cadaver in right lateral recumbency. A modified subcostal technique was performed on the opposite side using a linear ultrasound transducer and in-plane approach. Injection points (two 30 mL dye) were at the level of the TAP (between the rectus abdominis and transversus abdominis muscles and ventral to the cutaneous trunci muscle) perpendicular to: 1) the mid-point between the xiphoid cartilage and umbilical scar; and 2) at a point between the caudal and middle thirds of the abdomen measured from the first injection point to the umbilical scar. The modified subcostal approach was performed in seven additional cadavers in both hemiabdomens, with three cadavers in lateral and four cadavers in dorsal recumbency. Ultrasound guidance was used with all injections.ResultsThe standard approach stained the sixteenth to eighteenth thoracic nerves (T16–T18). The modified subcostal approach performed in lateral recumbency provided greater spread (T9–T17) than dorsal recumbency (T12–T18) (p = 0.016).Conclusions and clinical relevanceThe modified subcostal TAP approach resulted in extensive staining exceeding the standard approach. The nerves stained are consistent with production of ventral abdominal wall anesthesia in horses. Clinical studies are needed to verify these findings. 相似文献
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Carmela Gallo Giusi Barra Marisa Saponaro Emiliano Manzo Laura Fioretto Marcello Ziaco Genoveffa Nuzzo Giuliana dIppolito Raffaele De Palma Angelo Fontana 《Marine drugs》2020,18(12)
Immunotherapy takes advantage of the immune system to prevent, control, and eliminate neoplastic cells. The research in the field has already led to major breakthroughs to treat cancer. In this work, we describe a platform that integrates in vitro bioassays to test the immune response and direct antitumor effects for the preclinical discovery of anticancer candidates. The platform relies on the use of dendritic cells that are professional antigen-presenting cells (APC) able to activate T cells and trigger a primary adaptive immune response. The experimental procedure is based on two phenotypic assays for the selection of chemical leads by both a panel of nine tumor cell lines and growth factor-dependent immature mouse dendritic cells (D1). The positive hits are then validated by a secondary test on human monocyte-derived dendritic cells (MoDCs). The aim of this approach is the selection of potential immunotherapeutic small molecules from natural extracts or chemical libraries. 相似文献
5.
Patrizia De Gaetano rea M Doglioli Marcello G Magaldi Paolo Vassallo & Mauro Fabiano 《Aquaculture Research》2008,39(11):1229-1242
The modelling framework already introduced by Doglioli, Magaldi, Vezzulli and Tucci to predict the potential impact of a marine fish farm is improved following different directions, namely (1) real historic current-metre data are used to force the simulations, (2) settling velocity values specifically targeting Mediterranean fish species are used, and (3) a new benthic degradative module, the Finite Organic Accumulation Module, is added to the modelling framework. The Finite Organic Accumulation Module uses the output of the other functional units of the modelling framework to calculate the organic load on the seabed. The Finite Organic Accumulation Module considers the natural capability of the seafloor in absorbing part of the organic load. Different remineralization rates reflect the sediment stress level according to the work of Findlay and Watling. Organic degradation for both uneaten feed and faeces is evaluated by changing the release modality (continuous and periodical) and by varying the settling velocities. It is found that the maximum impact on the benthic community is observed either for quickly sinking uneaten feed released twice a day, or for less intense near-bottom current conditions. If both the above-mentioned scenarios coexist, a high stress level is established in the sediment. The model also suggests that the use of self-feeders in cages can reduce farm impacts significantly. These results show how the new and more complete modelling framework presented here is able to improve the objectivity in the decision-making processes and how it may be successfully used for planning and monitoring purposes. 相似文献
6.
Mario Augusto Pagnotta Linda Mondini Pasquale Codianni Clara Fares 《Genetic Resources and Crop Evolution》2009,56(3):299-310
Emmer wheat (Triticum dicoccon Schrank, 2n = 4x = 28) consists in a hulled wheat; its cultivation has been drastically reduced during the last century as a consequence of
its low yield. Recently, its agronomic and nutritive values, as well as the increase of popularity of organic agriculture,
have led to a renewed interest making its cultivation economically viable in the marginal lands with an increase of the cultivated
areas. In Italy, it mainly survives in few marginal lands of central and southern Italy, where local varieties, adapted to
the natural environment from where they originate, are used; moreover, some selected lines have also been developed. In the
present work, agro-morphological and qualitative traits, together with molecular analyses of 20 emmer accessions consisting
of Italian landraces, breeding lines, and cultivars, were performed. The field experiments were conducted for two consecutive
years (2001/2002–2002/2003) in two locations: Viterbo in central Italy, and Foggia in south Italy. The analyzed emmer wheat
accessions showed a good amount of genetic variability for both evaluated agro-morphological and molecular traits. This study
illustrates an increase in earliness, GY, TW, TKW, and YI going from landraces, breeding lines to cultivars, while the variability
does not change proportionally. 相似文献
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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
9.
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
10.
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: |