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排序方式: 共有250条查询结果,搜索用时 15 毫秒
41.
Valentina De Monte Francesco Staffieri Domenico Caivano Antonello Bufalari 《Acta veterinaria Scandinavica》2015,57(1)
A three-month-old female Rottweiler puppy was referred for intravascular correction of a previously identified cor triatriatum dexter. Echocardiography confirmed the presence of a hyperechoic membrane that divided the right atrium into a cranial and caudal chamber. A foramen in this membrane allowed the blood to flow from the caudal to the cranial chamber. Balloon dilation of the defect under transthoracic echocardiographic guidance was scheduled for the following day. The dog was premedicated with 0.5 μg/kg sufentanil and 0.2 mg/kg midazolam administered intravenously. General anaesthesia was induced with 2 mg/kg propofol and maintained with inhaled isoflurane in oxygen; at the same time, a constant rate infusion of 0.5 μg/kg/h sufentanil was administered by means of an infusion pump. Uneventful ventricular and supraventricular tachyarrhythmias developed during the placement of catheters and balloon dilation. At the end of procedure, when the guide wire and balloon catheter were removed, normal sinus rhythm was observed. To the authors’ knowledge, no previous reports have described the anaesthetic management of a balloon dilation procedure for cor triatriatum dexter in dogs. 相似文献
42.
Antonia Concetta Elia Valentina Ciccotelli Nicole Pacini Ambrosius Josef Martin Dörr Marilena Gili Mauro Natali Laura Gasco Marino Prearo Maria Cesarina Abete 《Fish physiology and biochemistry》2014,40(4):1055-1068
Oxytetracycline (OTC) is employed in fish farms to contest or prevent bacterial infections. We simulated an OTC treatment at therapeutic level (75 mg kg?1) and at higher doses (150, 300 mg kg?1) for 10 days. A withdrawal period of 10 days was considered for treated carp, carrying out the same chemical and biochemical analyses (total glutathione, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase and malondialdehyde). The aim was to obtain data related to the carryover in muscle and on variations in the antioxidant indicators in liver and kidney. The OTC residual levels in muscle showed a dose–response relationship. After 10 days of treatment at the recommended dose (75 mg kg?1), the mean value in muscle was 295 μg kg?1. After 10 withdrawal days, residues in all treated groups were not entirely eliminated by fish. Residues of recommended 75 mg kg?1 OTC dose were lower than the maximum permitted by EEC regulation: 100 μg kg?1. Disturbance in the antioxidant systems in liver and kidney was recorded in (150, 300 mg kg?1) carp, as well as during the withdrawal period. A lowered superoxide dismutase activity and higher levels of catalase, glutathione peroxidase, glutathione reductase and glutathione were evaluated in liver, while in kidney only higher malondialdehyde and glutathione S-transferase concentrations were recorded for 300 mg kg?1 dose. The therapeutic OTC dose exerted lower effects, and only in liver, enhancement of GPx and GR activities was recorded. After the withdrawal period, altered antioxidant responses in tissues were restored for all three OTC doses. 相似文献
43.
Detection and characterization of a rhabdovirus causing mortality in black bullhead catfish,Ameiurus melas 下载免费PDF全文
Giulia Bedendo Valentina Panzarin Andrea Fortin Gianpiero Zamperin Tobia Pretto Alessandra Buratin Rosita Quartesan Matteo Sabbion Cristian Salogni Francesco Pascoli Anna Toffan 《Journal of fish diseases》2018,41(7):1063-1075
This study fully describes a severe disease outbreak occurred in 2016 in black bullhead catfish farmed in Italy. Affected fish showed nervous clinical signs as well as emaciations and haemorrhagic petechiae on the skin at the fin bases, abdomen and gills. Viral isolation in cell culture allowed the subsequent identification of a rhabdovirus, tentatively named ictalurid rhabdovirus (IcRV), through electron microscopy, immunofluorescence and whole genome sequencing (WGS). The newly isolated virus, together with 14 additional viral strains stored in our repository and detected during similar mortality episodes in the period 1993–2016, was phylogenetically analysed on the basis of the nucleoprotein and the glycoprotein nucleotide and amino acid sequences. The genetic distances among Italian IcRV strains were also estimated. Our results show that all the IcRV strains belong to the genus Sprivivirus and are closely related to the tench rhabdovirus (TenRV). Italian catfish production is constantly decreasing, mainly due to viral infections, which include the newly characterized IcRV. Data presented in this work will assist to investigate the molecular epidemiology and the diffusive dynamics of this virus and to develop adequate surveillance activities. 相似文献
44.
Comazzi S Gelain ME Spagnolo V Riondato F Guglielmino R Sartorelli P 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(1):47-54
BACKGROUND: In dogs, flow cytometry is used in the phenotyping of immunologic cells and in the diagnosis of hemic neoplasia. However, the paucity of specific antibodies for myeloid cells and B lymphocytes and of labeled antibodies for multicolor techniques limits the ability to detect all leukocyte subpopulations. This is especially true for neoplastic and precursor cells. CD18 and CD45 are expressed on all leukocytes and are involved in cell activation, and together could be useful in helping determine cell lineage. OBJECTIVES: The purpose of this study was to double label canine blood for CD18 and CD45 and to use the differential expression of antigens to identify leukocyte populations in dogs with non-neoplastic and neoplastic hematologic diseases. METHODS: A template was developed using blood samples from 10 clinically healthy dogs and a back-gating technique. Differential leukocyte counts obtained with the template were compared with those obtained by manual and automated methods on blood samples from 17 additional healthy dogs. Blood samples obtained from 9 dogs with non-neoplastic (reactive) hematologic diseases and 27 dogs with hemic neoplasia were double stained for CD18 and CD45 using mouse anticanine CD18 monoclonal antibody (mAb) plus phycoerythrin-conjugated rat anticanine CD45 mAb and fluorescein isothiocyanate-conjugated rabbit antimouse IgG. Hemic neoplasms were diagnosed by cell morphology, and immunophenotypic and cytochemical markers. RESULTS: With the double label, neutrophils, eosinophils, monocytes, and T- and B-lymphocytes were identified. In reactive disorders, a population of activated neutrophils with high CD45 and CD18 expression was detected. In hemic neoplasia, cell lineage was easily determined, even in acute leukemia. CONCLUSIONS: Double labeling for CD18/CD45 may be useful as a screening method to evaluate hematologic diseases and help determine cell lineage, and to aid in the selection of a panel of antibodies that would be useful for further analysis. 相似文献
45.
A new test method for the evaluation of total antioxidant activity of herbal products 总被引:2,自引:0,他引:2
Zaporozhets OA Krushynska OA Lipkovska NA Barvinchenko VN 《Journal of agricultural and food chemistry》2004,52(1):21-25
A new test method for measuring the antioxidant power of herbal products, based on solid-phase spectrophotometry using tetrabenzo-[b,f,j,n][1,5,9,13]-tetraazacyclohexadecine-Cu(II) complex immobilized on silica gel, is proposed. The absorbance of the modified sorbent (lambda(max) = 712 nm) increases proportionally to the total antioxidant activity of the sample solution. The method represents an attractive alternative to the mostly used radical scavenging capacity assays, because they generally require complex long-lasting stages to be carried out. The proposed test method is simple ("drop and measure" procedure is applied), rapid (10 min/sample), requires only the monitoring of time and absorbance, and provides good statistical parameters (s(r)相似文献
46.
Canopy leaf to fruit ratio (L:F) of 6-year-old ‘Lapins’ sweet cherry trees on Gisela 5 rootstock was manipulated at the end of stage II (38 DAFB) of fruit development. While control trees showed a L:F ratio of 0.7:1 without alteration, on other trees young fruit were manually removed to yield L:F ratios of 2:1 and 3:1, respectively. All leaves and young fruit on trees were counted 30 DAFB. The effect of altering the source–sink ratio of whole trees on sweet cherry fruit quality parameters (fruit increment, fruit mass, color, total soluble solids content, contents of individual sugars and organic acids) was evaluated in the study. High leaf area to fruit (LA:F) ratios influenced significantly darkest fruit color, higher fruit mass, higher total soluble solids content and higher ratio between sugars and acids, which corresponded to better ripening stage. Contents of glucose, fructose and sorbitol, but not sucrose, sum of individual sugars, and the content of malic acid differed significantly among fruit of the different treatments. Fruit of the most advanced maturity stage (treatment 3:1) had the highest quality. Each day of improved L:F ratio counts towards better sweet cherry fruit quality. The results show that low L:F ratio influenced prolonged ripening process and delayed fruit maturity of ‘Lapins’ sweet cherry. 相似文献
47.
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49.
Eva-Maria Halbauer Valentina Bohinec Melanie Wittenberger Karin Hansel-Hohl Stephan Gaubitzer Eva M. Sehr 《Euphytica》2017,213(6):120
Agro-biodiversity is currently experiencing severe genetic erosion due to mankind’s unsustainable activities. Because of initiatives following the goal of the conservation of biological diversity, so far seven million crop accessions are being conserved ex situ in gene banks worldwide. Many of these accessions are landraces being rich in gene diversity, silently awaiting their proper characterisation. This is a very critical part of any long-term strategy to enhance the productivity and resilience of crops and agricultural systems and—most importantly—to ensure the preservation of our cultural and biological heritage. In this study of an ex situ germplasm evaluation we analysed 27 flax (Linum usitatissimum L.) accessions originating in the Alpine region, provided by five local gene banks/providers. Based on genomic microsatellite markers (gSSRs), a varying extent of accession-specific gene diversity (expected heterozygosity, HE) was revealed ranging from 0.05 to 0.51. Admixture of individuals between accessions was uncovered, pointing towards past processes related to gene bank management activities (e.g. intentional selection, unintentional cross-pollination during regeneration) or towards the evolution of the landrace itself (e.g. same regional origin, traditional naming), highlighting the co-existence of cultural and biological diversity. Such an genetic analysis of accessions stored ex situ not only produces valuable agronomic and breeding data, but also is useful for the clarification of past processes leading to duplicates within and between collections or mislabelling, contributing to the potential for rationalisation of collections, which in turn can help ensure that the limited resources available for regeneration are used most efficiently and effectively. 相似文献
50.
Luca Pipino Marie-Christine Van Labeke Andrea Mansuino Valentina Scariot Annalisa Giovannini Leen Leus 《Euphytica》2011,178(2):203-214
Fertility of hybrid tea roses is often reduced due to their interspecific origin but also to intensive inbreeding. New genotypes
used as pollen donors represent an economic risk for a breeding programme, as their influence on seed production is unknown.
In this study 11 cut rose genotypes were selected from a company database as high fertile or low fertile male parents, according
to the number of seeds per hybridisation. Pollen morphology and in vitro germination of the selected genotypes were characterised.
Pollen was either small (mean diameter <30 μm), shrunken, and irregular (abnormal), or large (mean diameter >30 μm), elliptical
and crossed by furrows (normal). High correlations were found between the number of seeds produced per hybridisation and the
pollen diameter (r = 0.94) or the percentage of normal pollen (r = 0.96). In order to evaluate the predictive power of the models, we conducted regression analyses and performed a validation
experiment on genotypes not present in the database and without background information on fertility. Pollen diameter and percentage
of normal pollen were characterised and fitted in the regression models for seed set predictions. Validation with an independent
dataset gave a good prediction for 83.3% of the data. This indicates that using either the mean pollen diameter or the percentage
of normal pollen resulted in effective fertility prediction. This tool could enhance the genetic variability in crossings
between hybrid tea roses, thus creating possibilities for less economically risky exploitation of new tetraploid genotypes
as male parents. 相似文献