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41.
An epidemiological survey for canine parvovirus (CPV) and canine coronavirus (CCoV) infections was conducted in Western Europe. A total of 156 faecal samples were collected from dogs with diarrhoea in Spain (n = 47), Italy (n = 39), France (n = 26), Germany (n = 21), the United Kingdom (n = 8), Belgium (n = 10), and the Netherlands (n = 5). Using molecular assays for virus detection and characterisation, CPV and CCoV were found to be widespread in European dog populations, either alone or in mixed infections. In agreement with previous reports, the original type CPV-2 was shown not to circulate in European dogs. The recently identified virus variant CPV-2c was predominant in Italy and Germany and present at high rates in Spain and France but was not detected in the UK or Belgium. Except for the UK, CCoV genotype I was identified in all European countries involved in the survey, albeit at a lower prevalence rates than CCoV genotype II.  相似文献   
42.
Acute contagious respiratory disease (kennel cough) is commonly described in dogs worldwide. The disease appears to be multifactorial and a number of viral and bacterial pathogens have been reported as potential aetiological agents, including canine parainfluenza virus, canine adenovirus and Bordetella bronchiseptica, as well as mycoplasmas, Streptococcus equi subsp. zooepidemicus, canine herpesvirus and reovirus-1,-2 and -3. Enhancement of pathogenicity by multiple infections can result in more severe clinical forms. In addition, acute respiratory diseases associated with infection by influenza A virus, and group I and II coronaviruses, have been described recently in dogs. Host species shifts and tropism changes are likely responsible for the onset of these new pathogens. The importance of the viral agents in the kennel cough complex is discussed.  相似文献   
43.
Olive oil processing industries generate substantial quantities of phenolic-rich byproducts, which could be valuable natural sources of antioxidants. This work is focused on the recovery and structural characterization of antioxidant compounds from olive mill wastewater (OMWW), a polluting byproduct of the olive oil production process. Phenolics were extracted from the waste material using a membrane technology coupled to low-pressure gel filtration chromatography on a Sephadex LH-20. The LH-20 fraction was, in turn, characterized for its phenolic composition by HPLC-DAD-MS/MS analyses. Verbascoside, isoverbascoside, β-hydroxyverbascoside, β-hydroxyisoverbascoside, and various oxidized phenolics were identified. Uptake of verbascoside, purified from the LH-20 fraction, by HT-29 cells, an established model system for studying drug transport properties, was also assayed. Finally, the antioxidant activities of the LH-20 fraction and verbascoside were characterized by two different techniques. Individual verbascoside was more active as a scavenger of reactive oxygen species and as a chemopreventive agent protecting low-density lipoproteins from oxidative damage than the LH-20 fraction.  相似文献   
44.

Purpose

An assessment of the effect of plant cover on the properties of four afforested soils in central Sicily was performed with the aim of discriminating among them after 60?years of afforestation.

Materials and methods

Chemical and biochemical soil analyses were coupled to fast field cycling (FFC) NMR relaxation investigations in order to monitor surface interactions of water in water-saturated soils.

Results and discussion

The traditional soil analyses revealed that the most stable soil properties such as soil texture and pH are not affected by 60?years of afforestation. Soils developed under eucalyptus trees showed larger amounts of hydrophilic organic matter as compared to the soils under pines and cypresses. FFC-NMR relaxometry data revealed that water, partitioned in clay-, loam-, and sand-type pores, showed longitudinal relaxation time values affected by the interactions with the soluble carbon content.

Conclusions

The results of the present study evidenced the potential of FFC-NMR relaxometry in differentiating the effect of diverse plant cover on chemical and hydrological properties of soils developed on the same parent material. In fact, in contrast with the traditional physicochemical and biochemical soil characterizations, which were unable to reveal differences among soils afforested with different plant species, FFC-NMR was capable of monitoring differences in water dynamics as affected by the presence of the most soluble soil organic material.  相似文献   
45.
Grapevine virus A (GVA) is considered one of the viruses associated with rugose wood (RW), one of the most economically important diseases of grapevine. Thirty-seven GVA isolates collected from grapevine cultivars from Marche (central-eastern Italy), Apulia and Campania (southern Italy), were subjected to molecular characterization. The genetic and population diversity was studied in the coat protein (CP) gene by RT-PCR-RFLP analysis with three restriction enzymes (MseI, AluI, and AciI), and nucleotide sequencing. A new primer pair (CP1F/R) allowing amplification of the whole CP gene (621 bp) was developed. RFLP with AciI yielded the highest number of variants in GVA isolates, showing seven different ‘simple’ profiles (A, B, C, D, E, F, and G). ‘Complex’ profiles were also found, and the most common variant combination was A + B in 39% of isolates. The analysis of GVA sequences confirmed the presence of plants infected with more than one GVA variant and suggested that RT-PCR-RFLP is suitable for evaluating population diversity of GVA enabling a screening of different haplotypes. The distribution of RFLP profiles and the phylogenetic analysis were not correlated with the location of infected plants, showing the presence of a GVA population with genetic diversity in the average with those of RNA viruses.  相似文献   
46.
Drugs that provide effective analgesia in cats are limited. The aim of the study was to assess the pharmacokinetics of grapiprant after 2 mg/kg administration via p.o. and i.v. routes in cats. Six healthy adult cats were used according to an open, single‐dose, two‐treatment, two‐period, randomized cross‐over design. Cats were assigned to two treatment groups and administered with 2 mg/kg of grapiprant (pure powder) through p.o. and i.v. administration. Blood samples were collected at preassigned times and analysed by a validated HPLC method. After both administrations, grapiprant concentrations were detectable in plasma for up to 24 hr in five of six animals. The critical parameters including clearance (173.2 ml hr?1 kg?1, range 120–326 ml hr?1 kg?1) and volume of distribution (918 ml/kg, range 611–1608 ml/kg) were calculated from the i.v. group. The mean oral F% was low (39.6% range 31.5%–45.2%). If the assumption that the minimal effective concentration in dogs (164 ng/ml) applies in cats too, grapiprant orally administered at 2 mg/kg might be effective for 10 hr. Further studies are necessary to establish the minimal effective concentration in this animal species.  相似文献   
47.
48.
The aim of this work is to study three soil solarizing film's (EVA, COE and BIO) effects on microbial biomass and their respiration activities and beside on some agronomic traits of tomato and melon as subsequent vegetable crop cultivation on solarized soil. The responses are that the used films increased different temperature levels in the soil; in fact, in the upper soil depth, BIO film, during the 37 days of solarization treatments, reached 137 h in which the recorded temperatures went over 60 °C, followed by EVA film with 80 h and COE film with 60 h affecting variously the thermic regime. The used films had great effects on all microbiological (MBC and MBN) and enzymatic parameters (alkaline phosphatase, acid phosphatase, β-glucosidase and arilsulphatase). Furthermore, the variation of root-knot nematodes (Meloidogyne javanica) on tomato and melon roots were assessed and some qualitative and yield traits of both vegetable crops were also reported as affected by soil solarization treatments. In all cases the BIO film has showed comparable yield results with EVA and COE films, with the advantage that it is compatible for a more sustainable agriculture practice.  相似文献   
49.
A pantropic canine coronavirus (CCoV) strain (CB/05) has been recently associated to a fatal outbreak of systemic disease in young dogs. We report the clinical, virological and serological findings in dogs experimentally infected with strain CB/05. The dogs, three 2.5-month-old and two 6-month-old pups, were successfully infected, shedding viral RNA with their faeces for the entire observation period (21 days) and displaying systemic clinical signs resembling those observed during the course of natural infection. Leucopenia (acute lymphopenia) occurred in all infected dogs, with values dropping below 60% of the initial counts. Considering the severity of the CB/05-induced disease, two of the youngest pups were euthanized for ethical reasons at days 8-9 postinfection, whereas the other pups underwent a slow but progressive improvement of their clinical status with complete recovery. At postmortem examination, remarkable lesions were observed in the internal organs of the euthanized pups, that tested positive for CCoV by real-time RT-PCR and virus isolation on cell cultures. All pups seroconverted for CCoV, as shown by the high optical density values and antibody titres detected by ELISA and virusneutralisation tests, respectively. The present study confirms that strain CB/05 is highly pathogenic for dogs, being able to induce a severe disease (and in some cases the death) even in experimental conditions.  相似文献   
50.
1. The aim of the study was to evaluate the pharmacokinetics (PKs) of tapentadol (TAP), a novel opioid analgesic, in laying hens after intravenous (IV) and oral (PO) administration and to quantify the concentrations of TAP residues in eggs.

2. Twenty healthy laying hens were divided into three groups: A (n = 6), B (n = 6) and C (n = 8). The study was conducted in two phases. Groups A and B received TAP by IV and PO routes at the dose of 1 and 5 mg/kg, respectively.

3. No visible adverse effects were observed after administration of the drug. TAP plasma concentrations were detectable up to 4 h following administration. Following IV administration, TAP plasma concentrations were only higher than the minimal effective concentration (148 ng/ml) reported for humans for 1 h. After single PO administration, plasma concentrations of TAP would not conform to software algorithms and the PK parameters were not calculated. TAP concentration following multiple PO doses at 5 mg/kg for 5 d was found to be higher and more persistent (12 h vs. 7 h) in yolk compared with albumen.

4. This is the first PK study on the novel atypical opioid TAP in laying hens. Further studies are required to investigate the analgesic efficacy and actual effective plasma concentration of TAP in this species.  相似文献   
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