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991.
The spread of both infectious and noninfectious diseases through wildlife populations is of increasing concern. Neoplastic diseases are rarely associated with population-level impacts in wildlife; however, impacts on individual health can be severe and might reflect deteriorating environmental conditions. An adult male free-ranging Blanding’s turtle (Emydoidea blandingii) originally captured in 2005 and deemed healthy, was recaptured in 2018 with a 1 × 1.5 cm intra-oral broad-based right mandibular mass. An excisional biopsy was performed, and histopathology revealed squamous cell carcinoma (SCC). Consensus herpesvirus PCR identified a novel herpesvirus (proposed name Emydoidea herpesvirus 2 [EBHV-2]) within the tumor. EBHV-2 shares 85% sequence homology with Terrapene herpesvirus 2 (TerHV-2), a herpesvirus linked to fibropapillomas in eastern box turtles (Terrapene carolina carolina). Virus-associated fibropapillomas have been identified in multiple marine turtle species and have had debilitating effects on their populations, but to date, virus-associated SCCs are rarely reported.  相似文献   
992.
A 3-mo-old, female Boer goat was presented because of respiratory difficulties. Tachypnea and inspiratory dyspnea were noted during physical examination. Thoracic radiographs were unremarkable; however, upper airway and nasal passage radiographs revealed a soft tissue mass within the nasal passages. The patient underwent cardiorespiratory arrest and did not respond to resuscitation efforts during endoscopy. A large, pedunculated, semi-firm mass originated from the soft palate and obstructed 90% of the nasopharynx on autopsy. Histologically, the mass was composed of primitive cells that multifocally formed tubules and glomeruloid structures intermingled with areas of fusiform and blastemal cells. The neoplastic cells were positive for cytokeratin (tubular and glomeruloid cells), vimentin (fusiform population and blastemal cells), and Wilms tumor 1 protein (glomeruloid structures) on immunohistochemistry, consistent with a triphasic nephroblastoma. To our knowledge, nasopharyngeal nephroblastoma has not been reported previously in any species.  相似文献   
993.
ObjectiveTo investigate the effect of cannabidiol (CBD) on sevoflurane minimum alveolar concentration (MACSEV) reduction produced by morphine in rats.Study designRandomized, blinded trial.AnimalsA total of 75 male Wistar Han rats weighing 276 ± 23 g (mean and standard deviation), aged 3 months.MethodsCannabidiol (CBD) was prepared in an ethanol-solutol-saline vehicle. Animals were randomly divided into 15 groups and given an intraperitoneal bolus of 1, 3, 5, 6.5, 7.5 or 10 mg kg?1 of CBD alone (CBD1, CBD3, CBD5, CBD6.5, CBD7.5 and CBD10 respectively) or combined with 5 mg kg?1 of morphine (MOR+CBD1, MOR+CBD3, MOR+CBD5, MOR+CBD6.5, MOR+CBD7.5 and MOR+CBD10). While three controls groups: MOR+saline, MOR+vehicle and vehicle were given an intraperitoneal bolus of morphine with saline, morphine with vehicle or vehicle alone respectively. The MACSEV was determined from alveolar gas samples at the time of tail clamp application. The MACSEV reduction was analyzed using a one-way ANOVA followed by Tukey’s test. Additionally, Kruskal-Wallis test for non-normally-distributed data was performed. Data are presented as mean ± standard deviation. P < 0.05ResultsThe mean MACSEV was not reduced by the action of CBD administered alone, but the addition of morphine to the different doses of CBD significantly reduced the MACSEV. That reduction was greatest in the MOR+CBD1, MOR+CBD7.5 and MOR+CBD10 groups (29 ± 5%, 32 ± 5% and 30 ± 6% respectively), less in MOR+CBD3 and MOR+CBD6.5 groups (24 ± 3% and 26 ± 4% respectively) and least in MOR+CBD5 group (17 ± 2%). However, only the MOR+CBD5 group was statistically significantly different from MOR+CBD1, MOR+CBD7.5 and MOR+CBD10 groups.Conclusions and clinical relevanceMACSEV in rat was unaltered by the action of CBD alone, the reduction in MACSEV produced by morphine was not enhanced by the addition of CBD at the doses studied.  相似文献   
994.
In order to identify the subunit design incurring the lowest costs, it is necessary to consider various factors, thereby assuring the correct hydraulic performance of the subunit. Water application costs with a sprinkler irrigation system comprise: investment cost (pumps plant, pipes, sprinklers, ditches), energy, manpower, maintenance and water costs. This work analyses the influence of different design and performance factors, such as subunit arrangement, spacing, working pressure, average application rate, and application efficiency on water application costs in a permanent set sprinkler irrigation subunit. The results show that the most important factor is the spacing between sprinklers. The next most important factor is the shape of the subunit (number of laterals and number of sprinklers per lateral). Working pressure is important too, since a decrease in pressure will result in a decrease in energy costs, although pipe diameter will need to increase. The higher the average application rate of the system, the higher the water application cost. The influence of irrigation efficiency is higher as water price increases. The water application cost can be reduced by 40% when application efficiency increases from 60% to 90%.Communicated by A. Kassam  相似文献   
995.
A field experiment was performed to study the effect of the space and time variability of water application on maize (Zea mays) yield when irrigated by a solid set sprinkler system. A solid set sprinkler irrigation layout, typical of the new irrigation developments in the Ebro basin of Spain, was considered. Analyses were performed (1) to study the variability of the water application depth in each irrigation event and in the seasonal irrigation and (2) to relate the spatial variability in crop yield to the variability of the applied irrigation and to the soil physical properties. The results of this research showed that a significant part of the variability in the Christiansen coefficient of uniformity (CU), and wind drift and evaporation losses were explained by the wind speed alone. Seasonal irrigation uniformity (CU of 88%) was higher than the average uniformity of the individual irrigation events (CU of 80%). The uniformity of soil water recharge was lower than the irrigation uniformity, and the relationship between both variables was statistically significant. Results indicated that grain yield variability was partly dictated by the water deficit resulting from the non-uniformity of water distribution during the crop season. The spatial variability of irrigation water depth when the wind speed was higher than 2 m s–1 was correlated with the spatial variability of grain yield, indicating that a proper selection of the wind conditions is required in order to attain high yield in sprinkler-irrigated maize.  相似文献   
996.
The nutrient fluxes of nitrate, ammonium, phosphorus and potassium in runoff and sediments were evaluated over a two-year period (1999–2000) on the taluses of terraces, in a zone of intense subtropical orchard cultivation (SE Spain). The erosion plots were located on a terrace of 214% (65°) slope, at 180 m in altitude and with 16 m2 (4 × 4 m) in area. Shrubby covers were tested for effectiveness in controlling the nutrient fluxes caused by runoff and sediments. Covers of Thymusserpylloides Bory sbsp. Gadorensis and Salvia officinalis L. reduced the NO3 - runoff losses by 53 and 48%, with respect to the bare soil without natural vegetation, the NH-4 + 61 and 56%; the PO4 -3 65 and 56%; and K+ 58 and 46%, respectively. A greater proportion of NO3 -, NH-4 + and K+ were transported in runoff than in sediments. Thyme and sage with respect to the control reduced NO3 - loss in sediments by 74 and 65%, NH-4 + by 71 and 62%, P by 72 and 67%, and K by 69 and 61%, respectively. The total loss (runoff and sediments) in the bare-soil plot for NPK was 260, 39 and 888 mg m-2 yr-1, in the sage plot 119, 15 and 460 mg m-2 yr-1, and in the thyme plot 105, 12 and 360 mg m-2 yr-1, respectively. The results show the importance of the plant covers in soil conservation and in the recycling of nutrients on terrace slopes. This has far-reaching implications in the sense that the control of pollution from erosion is vital in reducing the eutrophication of both surface waters and groundwater located in lowlands.  相似文献   
997.
In Zacatecas, Mexico, four plants are operating to extract Ag, Au, and Hg using CaS2O3 solution from surface soil containing tailings from the amalgamation method used during 1550–1900. The metal ions extracted are cemented by scrap Cu wires. Hg is separated by evaporation from the cemented amalgam and Ag and Au are obtained from the residue. A part of the soil to be leached was separated and leached as in the industrial process. Only 121 ppm of Hg was freed from 168 ppm of extractable Hg. About a half of the remaining Hg in the soil evaporated during 18 months. This confirms that the Hg in the soil is metallic. Pb and As are also freed in the same process. It is estimated that 13 000–34 000 t of Hg had been discarded in the extraction of Ag.  相似文献   
998.
We studied the environmental effects of the mining activity of Troya Mine on the fluvial ecosystem, in the Basque Country, Spain, from 1993 to 1995. The multivariate analysis of the physicochemical conditions shows that the main abiotic factors of variation are: (i) in the water column, a significant increase in the content of heavy metals and conductivity, and (ii) an intense accumulation of heavy metals in the bottom sediments. We studied the effects of these factors on density, richness, dominance, similarity coefficient and composition of the benthic macroinvertebrate community (BMI).We observed a de-structuring of the community. Richness decreases (from 25 to 11 different number of families), but it does not suitably value the impact. Density oscillates radically (255–1548 individuals m-2) and reflects changes occurred in sediments. Dominance, which oscillates from 0 to 1, increase from 0.16 upstream from the mine, to 0.42 downstream, fundamentally due to oscillations of Chironomidae, Tubificidae, Baetidae and Simuliidae. The similarity coefficient indicates the physicochemical variations both in the sediment and in the water column; this index is therefore suitable for the follow-up of the evolution of the disturbance studied. The families sensitive to disturbance in the water column are: Ephemeridae, Athericidae, Sericostomatidae, Leptophlebiidae, Baetidae, Gammaridae, Perlidae, Heptageniidae, and Leptoceridae; the tolerant ones are: Coenagrionidae, Hydrobiidae, Lumbricidae, and Polycentropodidae.With regard to the metal content in sediments, the sensitive families are: Gammaridae, Ephemeridae and Ceratopogonidae; the tolerant ones are: Simuliidae, Culicidae, Hydrophilidae, Dolichopodidae, Chironomidae, Psychodidae, Tipulidae, and Chrysomelidae.We thus synthesized the complexity inherent to this type of pollution, in which large amounts of variables are normally involved.  相似文献   
999.
In this article we report the relationships between heavy metals(Pb, Cd, Zn, Cu) in soil and settleable particulate matter usingdata from 6 yr at six different sampling points withinCartagena, a Spanish Mediterranean city. The use of enrichmentfactors and factor analysis allowed us to predict the majorsources of these metals. Soils were classified as one of threetypes: soils from polluted zone L, soils from polluted zone Z,and non-polluted soils. Settleable particulate matter was alsoclassified in the following three groups: Industrial zone, Urbanzone, and Intermediate zone. Enrichment factors showed that soilsfrom polluted zone L are enriched in Pb and Cd when compared with soils from polluted zone Z, and soils from polluted zone Zare enriched in Zn and Cu when compared with soils from pollutedzone L. In this context, soils from polluted zones L and Z areidentified as specific sources of metals in the settleableparticulate matter samples. We also suggest the importance ofanthopogenic contribution of metals to soil-enrichment fromancient times up to the present. This process was most severeduring the XIX century, when our city suffered an importantindustrial development. The concentration of these heavy metalsare also affected by regional meteorological conditions, whichinclude scarce rainfalls and a significant wind dispersion ofsoil aerosols.  相似文献   
1000.
The status of the populations of Podarcis pityusensis on about 70 islets and small islands around Ibiza and Formentera (Balearic Islands) is examined, using data from our own observations, and, to a lesser amount, other publications. Lizard populations were found on 43 islets, but data are lacking for another 13. Only 10 sites (18%) have abundant and well-maintained populations. In 13 localities (23%), there is no geographic isolation between the populations, or this isolation is very poor and incomplete. The high probability of populations mixing, or actual observation of this mixing, in 19 islands (34%) is indicated. Human pressure on lizard populations is strong in 14 cases (25%). And finally, 18 populations (about one third) may be considered highly endangered or already extinct by elimination or genetic mixing with other populations. Among the subspecies which became extinct through mixing are P.p. miguelensis, P.p. subformenterae, P.p. algae, P.p. sabinae and P.p. grueni. The need for adequate protective measures aimed at the conservation of the remaining populations is emphasized.  相似文献   
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