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31.
ObjectiveTo investigate the pharmacokinetics of carprofen after a single intravenous (IV) dose and multiple oral doses administered to pigs undergoing electroporation of the pancreas.Study designProspective experimental study.AnimalsA group of eight female pigs weighing 31.74 ± 2.24 kg (mean ± standard deviation).MethodsCarprofen 4 mg kg?1 was administered IV after placement of a central venous catheter during general anaesthesia with isoflurane. Blood samples were collected 30 seconds before and 5, 10, 20, 30 and 60 minutes and 2, 4, 6, 8, 12 and 24 hours after carprofen administration. Subsequently, the same dose of carprofen was administered orally, daily, for 6 consecutive days and blood collected at 36, 48, 60, 72, 96, 120, 144 and 168 hours after initial carprofen administration. Plasma was analysed using liquid chromatography with mass spectrometry. Standard pharmacokinetic parameters were calculated by compartmental analysis of plasma concentration–time curves. Data are presented as mean ± standard error.ResultsThe initial plasma concentration of IV carprofen was estimated at 54.57 ± 3.92 μg mL?1 and decreased to 8.26 ± 1.07 μg mL?1 24 hours later. The plasma elimination curve showed a bi-exponential decline: a rapid distribution phase with a distribution half-life of 0.21 ± 0.03 hours and a slower elimination phase with an elimination half-life of 17.31 ± 3.78 hours. The calculated pharmacokinetic parameters were as follows: the area under the plasma concentration–time curve was 357.3 ± 16.73 μg mL?1 hour, volume of distribution was 0.28 ± 0.07 L kg?1 and plasma clearance rate was 0.19 ± 0.009 mL minute?1 kg?1. The plasma concentration of carprofen, administered orally from days 2 to 7, varied from 9.03 ± 1.87 to 11.49 ± 2.15 μg mL?1.Conclusions and clinical relevanceCarprofen can be regarded as a long-acting non-steroidal anti-inflammatory drug in pigs.  相似文献   
32.
The effects of crop rotation and fertilization systems on yield and soil fertility parameters have been investigated in a long-term field trial established in southeast Norway in 1953. The results indicate the small differences between crop rotations and different fertilization systems in yield and soil fertility parameters; the decreasing trend in soil organic carbon (SOC) (from 3.8 to 3.7%) and increasing trend of N with time (from 0.32 to 0.36%) and, as a result, the decreasing trend in C/N ratio (from 12 to 10).  相似文献   
33.
After the accident in Fukushima reactors, a daily monitoring programme was initiated in two laboratories in Belgrade, one at the Vin??? Institute for Nuclear Sciences and the other at Institute for Occupational Health Karajovic. Samples of aerosol and fallout, as well as the random samples of food and water, were collected and analysed, using gross alpha/beta and gamma spectrometry, in order to establish the presence of traces of isotopes indicating Fukushima fallout. Gamma spectrometry measurement of these samples showed clear evidence of fission products 131I, 134Cs and 137Cs wtihin 2?weeks after the accident. The activity diminished with time due to dispersion in air and, in case of 131I, short half-life.  相似文献   
34.
This study discusses a novel approach for fabrication of floating photocatalyst which can be efficiently exploited for photodegradation of dyes in aqueous solutions. A fabrication of the floating photocatalyst consisted of two steps: transformation of the poly(ε-caprolactone) beads (PCLb) into poly(ε-caprolactone) foam (PCLf) with porous structure in supercritical carbon-dioxide and subsequent loading of PCLf with TiO2 nanoparticles (NPs). Morphological characterization of the PCLf before and after TiO2 NPs loading was carried out by FESEM. The presence of titanium on the surface and inside the PCLf was detected by EDX. Photocatalytical activity of the floating photocatalyst was investigated in aqueous solution of textile dyes C.I. Acid Orange 7 (AO7) and C.I. Basic Yellow 28 (BY28) which were exposed to lamp that simulates the sun light. In addition to sustainable floatability for a long period of time, developed floating photocatalyst exhibited high rate of photodegradation since the complete discoloration of AO7 and BY28 solutions and photocatalysts alone occurred after 300 and 180 min of illumination, respectively. Its photocatalytic activity was preserved after three repeated photodegradation cycles with unchanged chemical structure that was confirmed by FTIR analysis.  相似文献   
35.
The effect of suboptimal supply of nitrogen (N) and of replacing nitrate in the nutrient solution with ammonia on growth, yield, and nitrate concentration in green and red leaf lettuce was evaluated over two seasons (autumn and spring) using multiple regression analysis. The plants were grown in a greenhouse on a Nutrient Film Technique (NFT) system. Nitrogen concentrations in the nutrient solution were either 3?mM or 12?mM, and the form of N was varied as follows: 100% NO3, 50% NO3?+?50% NH4, and 100% NH4. In both seasons, the biomass (fresh weight) of lettuce heads increased with increasing NO3 concentrations and in autumn, NO3 even at 1.5?mM was sufficient for high yield. However, head dry weight was affected neither by the season nor by changes in the composition of the nutrient solution. The concentration of NO3 had no effect on root dry weight, but it decreased at higher concentrations of NH4. The number of leaves increased as the ratio of NO3 to NH4 in the nutrient solution increased and was higher in autumn because of the longer growth period. Increasing the concentration of NO3 in nutrient solution increased both total N and nitrate concentration in lettuce heads (dry weight) but decreased the concentration of total C. Also, leaf nitrate concentration was lower in spring than in autumn and decreased with increasing NH4 concentration. Nitrogen utilization efficiency was maximum when NH4 levels in the nutrient solution were either 0% or 50% irrespective of the season. Our results thus show that suboptimal N supply in autumn will not affect lettuce yield, and that nitrate concentration in leaves is lower when NH4 concentrations in nutrient solution are higher and also much lower in red lettuce than in green lettuce.  相似文献   
36.
37.
1. Distribution and status of medicinal leeches were re‐considered in the light of the new taxonomy recognizing four Western Palaearctic species: Hirudo medicinalis, Hirudo verbana, Hirudo orientalis and Hirudo troctina. 2. Recent records and new data obtained on expeditions to Ukraine, Russia, Azerbaijan, Kazakhstan, Uzbekistan and the Western Balkans were mapped to obtain an up‐to‐date overview of the distribution. 3. Three hypotheses explaining the current ranges of all Hirudo species were tested. The ecological hypothesis, suggesting a strong impact of large‐scale environmental factors, received the highest support, while anthropogenic influence was minimal, and no historical patterns of refugia and colonization were detected. 4. Mapped localities of all Hirudo species show extensive, belt‐shaped ranges extending from east to west. H. medicinalis is distributed from Britain and southern Norway to the southern Urals and probably as far as the Altai Mountains, occupying the deciduous arboreal zone. H. verbana has been recorded from Switzerland and Italy to Turkey and Uzbekistan, which largely corresponds to the Mediterranean and sub‐boreal steppe zone. H. orientalis is associated with mountainous areas in the sub‐boreal eremial zone and occurs in Transcaucasian countries, Iran and Central Asia. H. troctina has been found in north‐western Africa and Spain in the Mediterranean zone. 5. Based on the data gathered, and considering real and potential threats, global IUCN category Near Threatened is proposed for H. medicinalis, H. verbana, and H. orientalis, while H. troctina can only be assigned to category Data Deficient. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
38.
The European College of Veterinary Pathologists (ECVP) was established in 1995 with the aim of advancing veterinary pathology and promoting high standards within the specialty in Europe. The ECVP is one of 21 European colleges recognized by the European Board of Veterinary Specialisation (EBVS), which represents a quality-assurance system for European veterinary specialists. Until the ECVP was founded, there was no unified European system recognizing the specialty of pathology, and many European countries followed their own qualification systems, which varied in form and standard. The ECVP provides an annual certifying examination, the passing of which is required to gain membership (diplomate status) in the college. This qualification is now accepted on equal terms by the well-established American College of Veterinary Pathologists (ACVP). In line with EBVS requirements, the ECVP has also established a standard continuing professional development (CPD) and re-registration system for its membership. Furthermore, it has promoted and unified European post-graduate training in veterinary pathology by setting up requirements for residency training programs and making registration and monitoring of these programs by the ECVP a prerequisite for approval of an institution as a training facility. The concurrent establishment, together with the European Society of Veterinary Pathology, of an annual summer school that trains residents for the certifying examination has further fostered European post-graduate training. Within 10 years, the ECVP has succeeded in establishing common standards and a unified approach to veterinary pathology throughout Europe. This article describes the evolution and organization of the ECVP.  相似文献   
39.
Removing solids from liquid dairy manure slurry reduces manure phosphorus (P) and increases the available (mineral) fraction of nitrogen (N) but also decreases the organic matter content of the manure. While this novel treatment reduces environmental concerns associated with excess N and P application to soils, it may also reduce microbial biomass and activity in soil. This study evaluated the long-term effects of this alternative manure treatment compared to more typical nutrient applications in a perennial grass sward (tall fescue, Festuca arundinacea Schreb.) on soil microbial biomass, community composition, hydrolytic enzyme activity, and forage yield. Nutrient treatments for this long-term field experiment in Agassiz, British Columbia, Canada were started in 2003. The treatments included liquid dairy manure slurry, liquid dairy manure with solids removed, commercial fertilizer, a combination of fertilizer and dairy manure, and a control. All treatments were applied at 400–600 kg total N ha?1 year?1 in four equal doses. Soil microbial community composition (phospholipid fatty acid analysis) and activity (hydrolytic enzyme activity) were determined several times during the 2013 and 2014 growing seasons to a depth of 15 cm. Time of sampling (date) had a strong influence on microbial biomass, community composition, and activity, while the response to soil properties and yield was more varied. All manure treatments (dairy manure slurry, liquid fraction, and the combination) increased microbial biomass (by 19–32%) and the potential activity of cellulose-degrading enzymes (by 31–47%) compared to commercial fertilizer and unamended plots. The commercial fertilizer and liquid fraction lowered fungal/bacterial ratios compared with both whole manure and unamended plots. Our results indicate that separating the solid from the liquid fraction of manure, to improve crop yield and reduce P loading, did not reduce microbial community size and activity and that all manure treatments increased microbial biomass and activity compared to mineral fertilizer application.  相似文献   
40.
The aim of the study was to assess the role of pest control as a preventive measure in the control of trichinosis. The investigation was designed as a retrospective cohort study in the Virovitica-Podravina County. The incidence of trichinosis was determined according to the presence or absence of exposure to protective pest control measures. Differences in the rate of trichinosis infection were determined by calculating relative risk (RR), i.e., the ratio of absolute risk in the two groups. In this epidemiological study, data collected in the County area regularly covered by pest control (exposure area) were compared with other areas not covered by regular pest control measures (non-exposure area). The study included 132 subjects living in the County and locally infected with trichinosis. Patient data were obtained from their medical history, epidemiological survey and epidemiological questionnaire on the source (autochthony) of the disease. The study also included 133,028 domestic pigs, 875 wild animals (mostly wild boar) and 111 trapped rats. All samples were examined by the method of trichinoscopy at authorized veterinary institutions of the County. Trichinosis infection was recorded in 1012 of 79,534 domestic pigs in the area exposed to pest control measures and in 51 of 53,494 domestic pigs from the rest of the County. RR for the exposure area vs. non-exposure area was 13.35 (95% CI 10.08-17.68; p<0.05); according to particular areas, RR was 3.66 (95% CI 2.62-5.13) for Pitomaca, 22.47 (95% CI 13.27-38.08) for Slatina and 118.89 (95% CI 29.7-476.01) for Orahovica (p<0.05 all). Domestic pigs from the County areas exposed to regular pest control measures had a 13-fold likelihood of infection recorded in pigs from County areas where pest control measures were not or were only occasionally performed. Quite unexpectedly, these results revealed a failure of pest control to reduce the incidence of trichinosis. The spread of trichinosis obviously occurs by some routes obviating the impact of pest control.  相似文献   
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