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11.
Tramadol (T) is a centrally acting atypical opioid used for treatment of dogs. Piglets might experience pain following castration, tooth clipping and tail docking and experimental procedures. The aim of this study was to assess the pharmacokinetics of T and its active metabolite M1 in male piglets after a single intramuscular injection. Six healthy male piglets were administered T (5 mg/kg) intramuscularly. Blood was sampled at scheduled time intervals and drug plasma concentrations evaluated by a validated HPLC method. T plasma concentration was quantitatively detectable from 0.083 to 8 h. M1 was quantified over a shorter time period (0.083–6 h) with a Tmax at 0.821 h. The study demonstrated that piglets produce a larger amount of M1 compared with dogs, horses and goats. The human minimum effective concentration of M1 (40 ng/mL) was exceeded for over 3 h in piglets. If it is assumed to also apply to piglets, it could be speculated that the drug efficacy might exert its action over 3 h or longer. This assumption has to be confirmed by further specific pharmacokinetic/pharmacodynamic studies.  相似文献   
12.
Loss of semi-natural grasslands and reduction of habitat diversity are considered major potential threats to arthropod diversity in agricultural landscapes. The main aim of this study was to investigate how area and habitat diversity, mediated by shrub encroachment after grassland abandonment, affect species richness of orthopterans in island-like grasslands, and how contrasting mobility might alter species richness response to both factors. We selected 35 isolated patches in landscapes dominated by arable land (durum wheat) in order to obtain two statistically uncorrelated gradients: (i) one in habitat area ranging from 0.2 to 55 ha and (ii) one in habitat diversity ranging from patches dominated by one habitat (either open grasslands or shrublands) to patches with a mosaic of different habitats. Habitat loss due to land-use conversion into arable fields was associated with a substantial loss of species with a positive species-area relationship (SAR), with sedentary species having a steeper and stronger SAR than mobile species. Halting habitat loss is, therefore, needed to avoid further species extinctions. Shrub encroachment, triggered by abandonment, presented a hump-shaped relationship with habitat diversity. An increase in habitat diversity enhanced species richness irrespective of patch area and mobility. Maintaining or enhancing habitat diversity, by cutting or burning small sectors and by reintroducing extensive sheep grazing into abandoned grassland, are suggested as complementary strategies to mitigate further decline of orthopteran diversity in the remnant patches. This would be equally important in both small and large patches.  相似文献   
13.
Building on the early works of Alfred Marshall, analyses of local economies have emphasized the spatial function of clusters and industrial districts in terms of external economies of localization and agglomeration. Recent literature has emphasized the importance of culture and the complementarities between culture and local tangible and intangible assets. This paper aims to provide an analytical foundation for these processes with a view to developing tools for policy design, analysis and evaluation. By “system‐wide cultural districts,” we refer to a new approach to local development where cultural production and participation present significant strategic complementarities with other production chains. In this view, culture drives the accumulation of intangible assets such as human, social, and cultural/symbolic capital, thereby fostering economic and social growth and environmental sustainability.  相似文献   
14.
The Effect of Misoprostol on Aspirin-Induced Gastroduodenal Lesions in Dogs   总被引:1,自引:1,他引:0  
Misoprostol, a synthetic prostaglandin E1, analog, is effective in treating and preventing nonsteroidal antiin-flammatory drug (NSAID)-induced gastrointestinal lesions in humans. The effectiveness of misoprostol in preventing aspirin-induced gastroduodenal injury was studied in 3 groups of 6 adult mixed breed dogs. Group I received 3 μg/kg misoprostol PO tid. Group II received 3 μg/kg misoprostol PO tid and 35 mg/kg aspirin PO tid. Group III received 35 mg/kg aspirin PO tid. Endoscopy was performed on days 0, 5, 14, and 30. Five regions of the upper gastrointestinal tract were qualitatively scored from 1 to 12 based on the presence of submucosal hemorrhage, erosion, or ulceration, with ulceration receiving a higher numerical score than submucosal hemorrhage. A total score was assigned based on the sum of the scores from all regions. Comparisons among groups on each day were performed using the Kruskal-Wallis test. Differences within a group among different time periods were determined using appropriate multiple comparisons. Significant difference in mean gastroduodenal lesion score was found among all groups at 5, 14, and 30 days. Mean total score on days 5, 14, and 30 were as follows: group 1,5.0,5.2, 9.0; group II, 12.0, 12.7, 16.2; and group III, 26.0, 23.8, 21.5, respectively. Significant differences within a group among different time periods were found from days 0 to 5 in groups I and II, and from days 14 to 30 in group I. It was concluded that misoprostol effectively decreased endoscopically detectable mucosal lesions in dogs given aspirin.  相似文献   
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16.
A pulsed wave-Doppler ultrasonographic evaluation of common carotid arterial blood flow was carried out on 63 healthy Italian Saddlebred horses. Vessel diameter and tracing morphology were evaluated were evaluated and blood flow parameters (systolic, diastolic and mean velocity, acceleration and deceleration of the systolic wave, cartid pulse volume) were calculated and correlated with class variables (sex, age and body weight). On the basis of the presence of an incisure in the ascending branch of the systolic curve, subjects were divided in two groups: one with a bifid systolic curve and the other with a monophasic aspect. Correlations between: 1) diameter of the vessel and body weight and 2) carotid pulse volume and flow velocity (systolic, diastolic and mean) were found. A greater systolic pulse volume was found in male subjects, in subjects with greater body weight and in those which had a monophasic systolic wave.  相似文献   
17.
A West Nile virus (WNV) strain belonging to lineage 2 was for the first time detected in two pools of Culex pipiens collected in the province of Udine and in tissues of a wild collared dove (Streptopelia decaocto) found dead in the province of Treviso, in North East of Italy. It was molecularly identified by group and WNV lineage specific RT-PCRs and characterized by partial sequencing of the NS3 and NS5 genes. When compared with the sequences of same fragments of NS3 and NS5 of the WNV lineage 2 strain isolated from birds of prey in Hungary (2004), the phylogenetic analysis of these sequences revealed 100% and 99% similarity, respectively. As the Hungarian strain, the NS3 selected sequence differed from the 2010 Greek isolate by one amino-acid located at 249 site which is the site involved in genetic modulation of WNV pathogenicity. The Italian and Hungarian strains have histidine rather than proline at this site. The presence of a lineage 2 strain in regions where the lineage 1 strain is still circulating, creates a new scenario with unpredictable consequences. In this situation comprehensive investigations on the occurrence, ecology, and epidemiology of these different WNV strains circulating in Italy become the highest priority.  相似文献   
18.
Vitellogenin (Vtg) has proven to be a sensitive and simple biomarker in determining sex, sexual maturity, and xenoestrogenic effects in fish. Thus, our investigation has been focused on identification, partial characterization, and quantification of grey mullet (Mugil cephalus) Vtg through the use of a variety of biochemical and immunological analytical techniques. Mullet is considered both a promising aquaculture candidate and an important species for improving sediment quality in polyculture systems. In the first part of this work, grey mullet Vtg was purified from plasma of 17β-estradiol (E2)-induced male fish by a one-step chromatographic protocol, and partially characterized. Specific polyclonal antibodies were then raised against the mullet Vtg, and both an indirect ELISA and an optical immunosensor were set up and validated to quantify plasma Vtg. The indirect ELISA and the optical immunosensor assay developed showed linear measuring in the range 56.8–1047.1 ng mL−1 and 70–739 ng mL−1 Vtg concentrations in standard solutions, respectively. The results obtained suggest that the indirect ELISA allows Vtg detection over a wide dynamic range, thus resulting more suitable for rapid and sensitive sample screening. Therefore, we suggest that the direct immunosensor is a promising tool which needs more investigation to improve the sensitivity.  相似文献   
19.
Pelagic fish stocks in the Java Sea have been exploited intensively since the beginning of the 1970s. However, due to the effect of increased fishing power of the fleets and the changing nature of spatial and temporal distribution of the fishing effort, assessment of stock trends based on commercial data of catch and effort requires the standardization of both effort and catch data. Here we present the first attempt to reconstruct a standardized time series of commercial catch per unit of effort (CPUE) for the main pelagic species exploited by the purse seine fleet in the Java Sea. The results showed that all the stocks analysed have largely declined since the beginning of the 1990s. For bigeye scad, Indian mackerel and sardine, current estimates are only between 3 and 19% of the maximum observed value while round scads and spotted sardine biomass estimates lie between 18 and 34%. However, our assumptions about the effect of lamp power and level of creeping and the fact that the influence of fish density on catchability and the effect of targeting were not taken into account thus observed decline is a rather conservative estimate of the real decline of the stocks. If effective management actions are not put in place as a matter of urgency in the Java Sea for small pelagic fisheries, one runs the risk of adding those species to the long list of overexploited stocks of the world oceans.  相似文献   
20.
We analyzed guava fruits (Psidium guajava L. cv. Red Suprema) from Cuba to determine their chemical composition, total antioxidant capacity, as well as their protective effect against oxidative damage using an in vitro model of human dermal fibroblasts. The guava fruit is a natural source of bioactive compounds, such as polyphenols, vitamin C, folates and beta carotenes with proven health benefits. Human dermal fibroblasts were pre-incubated with different concentrations of guava crude extract and then subjected to oxidative stress using the AAPH stressor. The number of apoptotic and dead cells, as well as the markers of oxidative damage such as lipid and protein oxidation significantly decreased when cells were pre-incubated with guava crude extract and then exposed to the stressor. The activity of antioxidant enzymes also improved when cells were pre-incubated with guava crude extract in comparison to cells subjected to stress without prior pre-incubation with the guava extract. The results obtained in this study highlight the health benefits of guava regarding oxidative stress, proving it to be an important source of bioactive compounds associated with important biological properties.  相似文献   
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