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11.
Microchips are commonly used in companion, research, and zoo animal medicine for easy, reliable, and cost-effective identification with relatively low risk of side effects. This report describes development of a metastatic leiomyosarcoma associated with a microchip in an Egyptian fruit bat (Rousettus aegyptiacus).  相似文献   
12.
Jacobs  Douglass F.  Rose  Robin  Haase  Diane L.  Morgan  Paul D. 《New Forests》2003,26(3):263-277
This experiment evaluated the influence of manure, peat, and vermiculite incorporated at low and high rates (0.0118 and 0.0236 m3/m2) and under two soil moisture regimes on Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedling (1+0 for 1+1) xylem water potential (xylem), whole-plant growth, root architectural development, and subsequent field performance under fertilized and non-fertilized conditions. Trends in soil moisture retention were observed (high manure > high peat > control) but there were no differences in xylem. Root length in the wetter soil moisture experiment was initially (three months) greatest for seedlings in high vermiculite and least in high manure but there were no differences among treatments at lifting (eight months). Mean height was greatest for seedlings grown in vermiculite and peat (wetter nursery experiment) after two field seasons. Field fertilization (35 g/seedling) with controlled-release fertilizer in the planting hole stimulated height growth initially, but decreased height and diameter growth during the second growing season. Dramatic improvements associated with the use of nursery soil amendments were not realized, but the failure to identify negative effects, a potential reduction in disease incidence, and improvement of nursery soil physical and chemical properties may justify their use.  相似文献   
13.
14.
Understanding how environment, crop management, and other factors, particularly soil fertility, influence the composition and quality of food crops is necessary for the production of high-quality nutritious foods. The flavonoid aglycones quercetin and kaempferol were measured in dried tomato samples (Lycopersicon esculentum L. cv. Halley 3155) that had been archived over the period from 1994 to 2004 from the Long-Term Research on Agricultural Systems project (LTRAS) at the University of California-Davis, which began in 1993. Conventional and organic processing tomato production systems are part of the set of systems compared at LTRAS. Comparisons of analyses of archived samples from conventional and organic production systems demonstrated statistically higher levels (P < 0.05) of quercetin and kaempferol aglycones in organic tomatoes. Ten-year mean levels of quercetin and kaempferol in organic tomatoes [115.5 and 63.3 mg g(-1) of dry matter (DM)] were 79 and 97% higher than those in conventional tomatoes (64.6 and 32.06 mg g(-1) of DM), respectively. The levels of flavonoids increased over time in samples from organic treatments, whereas the levels of flavonoids did not vary significantly in conventional treatments. This increase corresponds not only with increasing amounts of soil organic matter accumulating in organic plots but also with reduced manure application rates once soils in the organic systems had reached equilibrium levels of organic matter. Well-quantified changes in tomato nutrients over years in organic farming systems have not been reported previously.  相似文献   
15.
A Yorkshire terrier dog was presented for episodes of “star gazing” behavior expressed as upward raising of the head and neck extension with subsequent staring at the ceiling or sky. Erosive gastritis with reflux esophagitis was diagnosed. Treatment of these conditions was associated with resolution of the behavior, suggesting a causal link.  相似文献   
16.
Low pathogenicity avian influenza virus (LPAIV) and lentogenic Newcastle disease virus (lNDV) are commonly reported causes of respiratory disease in poultry worldwide with similar clinical and pathobiological presentation. Co-infections do occur but are not easily detected, and the impact of co-infections on pathobiology is unknown. In this study chickens and turkeys were infected with a lNDV vaccine strain (LaSota) and a H7N2 LPAIV (A/turkey/VA/SEP-67/2002) simultaneously or sequentially three days apart. No clinical signs were observed in chickens co-infected with the lNDV and LPAIV or in chickens infected with the viruses individually. However, the pattern of virus shed was different with co-infected chickens, which excreted lower titers of lNDV and LPAIV at 2 and 3 days post inoculation (dpi) and higher titers at subsequent time points. All turkeys inoculated with the LPAIV, whether or not they were exposed to lNDV, presented mild clinical signs. Co-infection effects were more pronounced in turkeys than in chickens with reduction in the number of birds shedding virus and in virus titers, especially when LPAIV was followed by lNDV. In conclusion, co-infection of chickens or turkeys with lNDV and LPAIV affected the replication dynamics of these viruses but did not affect clinical signs. The effect on virus replication was different depending on the species and on the time of infection. These results suggest that infection with a heterologous virus may result in temporary competition for cell receptors or competent cells for replication, most likely interferon-mediated, which decreases with time.  相似文献   
17.
Current and past industrial pollution leaves many traces in the environment, in particular along rivers in industrial and urban areas. The isotopic analysis of the lead found in soils and tree rings offers a kind of environmental archive for presenting a portrait of the pollutant distribution in the environment in both spatial and temporal terms. This study is an attempt to identify and compare the source of contamination found in soils and tree rings located along two rivers affected by pollution over several years. Specifically, the focus is on the pattern of lead concentrations and lead isotopic signatures (206Pb/207Pb, 208Pb/206Pb, and 206Pb/204Pb) detected in soils and tree rings located on polluted floodplains. The concentration of Pb in overbank sediments does not rise with the increasing distance downstream from the point source (mining area), suggesting that significant fluvial transport of the pollutant particles over 80 km is involved. For the soil profiles, Pb concentration levels range between 12.32 and 149.13 mg/kg, with the highest concentrations found at the base of the profiles (>1 m). For the lead isotope ratios in the soil profiles, the values obtained range from 0.851 to 0.872 (206Pb/207Pb), 2.081 to 2.111 (208Pb/206Pb), and 0.547 to 0.562 (206Pb/204Pb). The tree ring analysis of red ash (Fraxinus pennsylvanica Marsh.) shows average lead concentrations of 0.63 μg/g, and the lead values of all the tree specimens range between 0.03 and 11.38 μg/g. Pb concentrations varied greatly between the specimens in selected sites and lead isotope ratios in the tree rings showed a strong variability in the time series, particularly from 1945 to 1970. The greater number of variations in the lead concentration rates and isotopic ratios suggest that many more events associated with pollution and contamination have in fact occurred in this area. The study demonstrates the utility of combining stable isotope analyses (soils and tree rings) to examine the source and dispersion of contaminant Pb in fluvial systems by providing reliable and robust indicators for the detection of environmental changes on a local and regional scale.  相似文献   
18.
An in utero tibial fracture was examined at necropsy in a seven-month-old male aborted Thoroughbred fetus. Grossly the healed fracture had a smooth cortical surface. Histologically there was no callus formation or excessive osteoclastic or osteoblastic activity.  相似文献   
19.
OBJECTIVE: To optimize methods for the use of computed tomography (CT) to assess pathologic changes in the lungs of calves and to determine the effect of treatment on lung consolidation. ANIMALS: 10 male Holstein calves. PROCEDURES: Calves were anesthetized to facilitate CT imaging of the thorax. After initial images were obtained, pneumonia was induced in the calves by inoculation through a bronchoscope. Two calves were used in a preliminary study to refine the inoculation dose and optimize CT images. Four calves were administered florfenicol and 4 calves were untreated control animals. Serial images were obtained 24, 48, and 72 hours after inoculation. After final images were obtained, calves were euthanized, and lung consolidation was estimated by use of lung surface area scoring and water displacement. These estimates were compared with estimated lung consolidation obtained by use of CT. RESULTS: Calves had rapid disease progression. Percentage of lung consolidation was not significantly different between treatment groups for any of the estimation methods. Results of an ANOVA of the 3 assessment methods indicated significant differences among methods. Estimates of the percentage of lung consolidation obtained by use of surface area scoring and CT correlated well, whereas water displacement estimates correlated poorly with other methods of consolidation estimation. CONCLUSIONS AND CLINICAL RELEVANCE: Because of the correlation with other methods for estimation of lung consolidation, CT has the potential to be used to monitor disease progression in calves with experimentally induced respiratory tract disease.  相似文献   
20.
Summary Populations of wild emmer wheat, Triticum dicoccoides, in Israel, originating from diverse habitats, and tested earlier for allozyme (Nevo et al., 1982) and disease resistance polymorphisms (Moseman et al., 1983a, 1983b; Nevo et al., 1984a, 1984b), were compared and contrasted for performance in agronomically important phenotypic traits. The traits compared involved 10 variables comparing germination, earliness, biomass and yield variables. The field experiments were conducted in 1980, 1981 and 1982 in two relatively standardized and contrasting environments: mesic (Mount Carmel, Haifa) and xeric (Acedat Farm, and Sede Boqer, in the northern Negev desert). The experimental design involved 12 population quadrangles at Avedat Farm in 1980, and rows of randomized genotypes of five populations in both Haifa and Sede Boqer in 1981 and 1982.The results indicate that the characters studied are partly genetically determined. Striking genetic variation was found between and, at least in some characters, also within populations in each site, whereas remarkable environmental variation including genetic-environmental interaction was found between the mesic and the xeric sites. We conclude that natural populations of wild emmer wheat in Israel vary not only in genetic polymorphisms of allozymes and disease resistance, but also in quantitative traits of agronomic importance. These traits are economically significant and should be conserved and utilized in wheat crop improvement.  相似文献   
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