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51.
The purpose of this study was to assess the diagnostic utility of parathyroid ultrasonography to differentiate causes of hypercalcemia in dogs. We analyzed qualitative and quantitative ultrasound imaging findings and clinical pathology data from 33 dogs that underwent parathyroid ultrasound examination as part of the diagnostic evaluation for hypercalcemia. Diagnoses of the diseases causing hypercalcemia included parathyroid carcinoma (n = S), parathyroid adenoma (n = 15), parathyroid adenomatous hyperplasia (n = 6), chronic renal insufficiency (n = 3), and hypercalcemia of malignancy (n = 4). All parathyroid lesions were round or oval and hypoechoic compared with surrounding thyroid parenchyma. Adenomatous and adenocarcinomatous glands were 4 mm or larger in longest linear measurement on US examination and were statistically significantly larger than hyperplastic glands. (p < 0.001) Linear measurements of parathyroid glands acquired at the time of ultrasound examination correlated well with direct siz determination after surgical excision. (r2= 0.9, p < 0.0001) Parathyroid lesions <4 mm are highly suspicious for parathyroid adenoma or carcinoma, while US lesions <4 mm most likely represent primary adenomatous hyperplasia or secondary parathyroid hyperplasia. Parathyroid size estimation from ultrasound examination is an accurate predictor of true size.  相似文献   
52.
Aujeszky's disease has been the subject of an eradication campaign in Denmark since 1980. A detailed knowledge of the virus strains present in the country was provided by restriction fragment analyses of older clinical isolates, and of isolates from all the virologically confirmed outbreaks since 1985. The introduction of foreign strains into southern border areas was demonstrated during the winters of 1984/85, 1986/87 and 1987/88. An epizootic during the winter of 1987/88 was shown to correlate with an unusual predominance of southerly winds. Both conventional and specific pathogen free herds became infected. A herd level case-control analysis of the outbreaks during the winter of 1987/88 revealed that there was a positive correlation between the risk of infection and the size of the herd. The observations support the hypothesis of airborne transmission of the disease.  相似文献   
53.
Quantitative measurement of cerebral ventricle volume of eight English bulldogs was performed using magnetic resonance (MR) imaging. The mean ventricular volume was 14.8 ml. with a range of 8.6 m1.-38.1 ml. The mean ventricular volume of two beagles was 2.2 ml with a range of 0.7 m1.3.7 ml. The percent of intracranial volume occupied by ventricle was found to be significantly larger in bulldogs (14.0%; S.D. = 7.9%) than in beagles (Range = 1.048%). The relationship between the percent of intracranial volume occupied by ventricle and measurements of body weight, age, sex, and various measures of skull anatomy of the bulldog was also determined. The relationship between ventricular volume and neurologic dysfunction was examined. There was a possible trend between high percent of intracranial volume occupied by ventricle and low body weight. This study will serve as a pilot study for examining the relationship between ventricular volume and neurologic disease in bulldogs.  相似文献   
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Nutrient element concentrations and grain quality were assessed in spring wheat grown under elevated CO2 concentrations and contrasting levels of tropospheric ozone at different nitrogen supply rates at several European sites. Carbon dioxide enrichment proved to affect nutrient concentrations in a complex manner. In green leaves, all elements (with exception of phosphorus and iron) decreased. In contrast, effects on the element composition of grains were restricted to reductions in nitrogen, calcium, sulphur and iron. Ozone exposure resulted in no significant effects on nutrient element concentrations in different tissues in the overall analysis. The nitrogen demand of green tissues was reduced due to CO2 enrichment as shown by reductions in the critical leaf nitrogen concentration and also enhanced nitrogen use efficiency. Reductions in the content of ribulose-bisphosphate carboxylase/oxygenase and repression of the photorespiratory pathway and reduced nitrogen allocation to enzymes driving the photosynthetic carbon oxidation cycle were chiefly responsible for this effect. Thus, nitrogen acquisition by the crop did not match carbon acquisition under CO2 enrichment. Since crop nitrogen uptake from the soil was already completed at anthesis, nitrogen allocated to the grain after anthesis originated from vegetative pools—causing grain nitrogen concentrations to decrease under CO2 enrichment (on average by 15% when CO2 concentrations increased from 360 to 680 μmol mol−1). Correspondingly, grain quality was reduced by CO2 enrichment. The Zeleny value, Hagberg value and dry/wet gluten content decreased significantly with increasing [CO2]. Despite the beneficial impact of CO2 enrichment on growth and yield of C3 cereal crops, declines in flour quality due to reduced nitrogen content are likely in a future, [CO2]-rich world.  相似文献   
57.
Bioavailability of dietary folate might be impaired by the polyglutamate chain to which approximately 70% of dietary folates are bound. This chain must be removed enzymatically in the intestine before folate is absorbed as a monoglutamate. To increase formation of monoglutamate folate in vegetables, the vegetables were subjected to various processing treatments. Treatments included freezing (-18 degrees C, 16 h) and thawing (4 degrees C, 24 h) and hydrostatic high-pressure treatment (200 MPa, 5 min). Both freezing/thawing and high-pressure treatment increased the proportion of folate in the monoglutamate form in leeks, cauliflower, and green beans 2-3-fold. However, loss of total folate after these treatments was >55%. It is concluded that conversion of folate polyglutamate to the monoglutamate form in vegetables is possible by certain processing treatments. Potentially this could lead to vegetables with higher folate bioavailability. However, to prevent folate loss into processing water, processing in a closed system should be applied.  相似文献   
58.
The contribution of animal slurry to the supply of S to plants was studied. The total-S content of cattle and pig slurry was significantly correlated to DM and nitrogen content and was composed of sulfide, sulfate and C-bonded S. During 42 weeks of storage sulfate concentrations decreased and sulfide and C-bonded S concentrations increased. In a pot experiment plant-availability of S in slurry was found to be low, 5 to 7% of total-S.  相似文献   
59.

The performance of lab-scale compostbiofilters for the purification of waste gasescontaining high (>70 mg m-3) ammoniaconcentrations was studied. When using fresh compostmaterial, no effect of inoculating the compostmaterial with a nitrifying culture was observed sincehigh elimination capacities (up to 350 gNH3 m-3 d-1) were obtained in both theinoculated and the non-inoculated biofilter. Due tothe physico-chemical interaction of NH3 with thecompost material at the start of the experiment, nomicrobiological start-up period was observed and highremoval efficiencies were obtained from the first dayon. Next to this, no NH3-toxicity was observedeven at concentrations up to 550 mg NH3 m-3.About 50% of the NH3-removal was found to benitrified, while the other 50% remained in thebiofilter as NH +4 . As a result of this, noacidification of the carrier material was observed andNH4NO3 accumulated in the biofilter. Due toosmotic effects, however, a complete inhibition innitrification and NH3-removal was obtained at ameasured NH4NO3-concentration in the compostmaterial of 6–7 g N kg-1, corresponding to acumulative NH3-removal in the biofilter of ±6000 g m-3. Finally, it was illustrated that theremoval of the odorant dimethyl sulfide (Me2S) ina Hyphomicrobium MS3-inoculated compostbiofilter is completely inhibited due toNH3-toxicity at a waste gas concentration of 100 mg NH3 m-3. Next to this, theNH +4 - and NO ?3 -concentrations inthe compost material that were shown to inhibit thenitrification, also strongly affected theMe2S-degrading activity of Hyphomicrobium MS3.

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60.
When semi-natural pastures are abandoned, specialized grassland species are lost as a consequence of succession. As a counter-measure, previously abandoned grasslands may be restored by clearing shrubs and trees and re-introducing grazing livestock. In order to examine the effects of this type of habitat restoration, we compared species richness of plants and of specialized plants thought to be dependent on continuous management and species richness and abundance of butterflies and red-listed butterflies in 12 sets of matched continuously managed, abandoned and restored grassland in southern Sweden. We found no differences in species richness or abundance between the three grassland types. There were, however, some negative effects of abandonment. The number of management-dependent plants decreased with increasing cover of trees and shrubs, and in restored sites species richness of all groups decreased with increasing cover of trees and shrubs before restoration. Also the present management significantly affected both butterflies and plants. Species richness of both groups increased with increasing vegetation height and differed between sites depending on the species of grazers, with negative effects of sheep compared to cattle or horses. Our study indicates that for grassland management to be efficient, the restoration actions should mainly be directed towards sites where the post-abandonment succession has not proceeded too far.  相似文献   
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