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202.
Eight pedotransfer functions (PTF) originally calibrated to soil data are used for evaluation of hydraulic properties of soils and deeper sediments. Only PTFs are considered which had shown good results in previous investigations. Two data sets were used for this purpose: a data set of measured pressure heads vs. water contents of 347 soil horizons (802 measured pairs) from Bavaria (Southern Germany) and a data set of 39 undisturbed samples of tertiary sediments from deeper ground (down to 100 m depth) in the molasse basin north of the Alps, containing 840 measured water contents vs. pressure head and unsaturated hydraulic conductivity. A statistical analysis of the PTFs shows that their performance is quite similar with respect to predicting soil water contents. Less satisfactory results were obtained when the PTFs were applied to prediction of water content of sediments from deeper ground. The predicted unsaturated hydraulic conductivities show about the same uncertainty as for soils in a previous study. Systematic deviations of predicted values indicate that an adaptation of the PTFs to the specific conditions of deeper ground should be possible in order to improve predictions.  相似文献   
203.
Influence of temporary stockpiling on the initial development of restored topsoils Due to increasing construction and open‐cast mining activities on fertile agricultural land, excavation, stockpiling, and restoration of soils have become important issues in soil protection. In this study, we performed a restoration experiment to investigate how the conditions during stockpiling may influence initial soil development and plant growth on a restored site. Four topsoils, which originated from two depths (with uninhibited and inhibited aeration) of a nontrafficked and a trafficked topsoil deposit, were repacked in strips and sown with three meadow‐seed mixtures in strips perpendicular to the soil strips. During stockpiling as well as during the first 2 years after restoration, we assessed the physical and mechanical properties of the topsoils and (after restoration) also plant growth. None of the investigated properties of the topsoils was influenced by the depth in the deposit. In contrast, the coarse porosity and compression index were lower, whereas the bulk density and precompression stress were higher in the trafficked than in the nontrafficked topsoil deposit. However, these differences largely disappeared already in the course of soil restoration. Contrary to our expectations, the plants grew better on the soil of the trafficked topsoil deposit than on the soil of the nontrafficked topsoil deposit in the year of restoration. This might be attributed to the extremely dry and hot summer of that year. In the course of the 2 years following restoration, also the differences in plant growth tended to disappear. The remaining differences in bulk density and plant growth could not be attributed to differences in stockpiling conditions. The results suggest a re‐examination of current soil restoration guidelines. The maximum permitted stockpiling heights for topsoils might be increased in order to reduce the areas required for temporary stockpiling.  相似文献   
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The following case report describes a 1‐year‐old female cheetah (Acinonyx jubatus) with bilateral blindness and unresponsive pupils. For comparison, a second healthy 2.5‐year‐old male cheetah without visual deficits was also examined. Clinical examination of both animals included biomicroscopy, indirect ophthalmoscopy, tonometry, and electroretinography. The young female cheetah showed no menace response, no direct or indirect pupillary light reflex, and no dazzle reflex in either eye. Fundus lesions, as detected by indirect ophthalmoscopy, are described for the female animal. In both eyes, the fundus color was green/turquoise/yellow with multiple hyperpigmented linear lesions in the tapetal area around the optic nerve. The optic nerve head was dark gray and about half the normal size suggesting bilateral optic nerve hypoplasia and retinal dysplasia or differentially optic nerve atrophy and chorioretinal scarring. The ERG had low amplitudes in the right eye but appeared normal in the left eye compared with the male cheetah. Blood levels did not suggest current taurine deficiency. This is addressed to some degree in the discussion. Bilateral optic nerve hypoplasia or optic nerve atrophy is a rare anomaly in cats and has not yet been described in a cheetah.  相似文献   
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Bernese Mountain dogs (BMDs) are prone to develop a familial glomerulonephropathy and a pathogenic role of Borrelia burgdorferi sensu lato in this disease has been suspected. Glomerular disease in many affected dogs is clinically inapparent and proteinuria is found incidentally. In this study, urine protein excretion was evaluated in 122 clinically healthy BMDs and 55 controls. The seroprevalence of B. burgdorferi in BMDs was 57%, compared to 16% in controls. There were no significant differences in the occurrence of positive dipstick results, microalbuminuria, urine protein-to-urine creatinine ratio or abnormal urine protein pattern (determined by sodium dodecyl sulphate agarose gel electrophoresis) between BMDs and controls and BMDs with and without antibodies against B. burgdorferi. It was concluded that antibodies against B. burgdorferi are not associated with proteinuria as an early sign of renal disease in BMDs.  相似文献   
208.
To relate thyroid size to routine blood parameters and T(4) status the ventral neck of 161 cats with clinical signs consistent with hyperthyroidism was examined by two independent observers using a semi-quantitative palpation system. Thyroid gland size of each side was scored from 0 (non-palpable) to a maximum of 6 (>25 mm). In 127 of the 161 cats, at least one thyroid gland was palpable. The palpation score was significantly correlated with the T(4) concentration. The 17 hyperthyroid cats had significantly higher palpation scores than the 110 euthyroid cats. Euthyroid animals with a palpation score >or=3 were significantly older, had higher body weights, lower alkaline phosphatase, alanine aminotransferase, phosphate, and urine specific gravity, but higher lipase and creatinine concentrations than hyperthyroid cats. Our study demonstrates that although no reliable conclusion on the functional status of the thyroid can be drawn based on its size the likelihood of hyperthyroidism increases with increasing size of the gland.  相似文献   
209.
Purpose X-linked juvenile retinoschisis (XLRS) is the most common juvenile maculopathy in men and is caused by mutations in the gene encoding retinoschisin (RS1). Evidence in the literature on the therapeutic effect of carboanhydrase inhibitors (CAIs) to treat schisis formation in the retina has remained equivocal. Here, we evaluate the effect of the CAI dorzolamide on the structural and functional disease progression in the mouse model for XLRS (Rs1h(-/y) ). Methods Rs1h ( -/y ) mice were treated unilaterally with dorzolamide eye drops (Trusopt(?) 20?mg/mL) every 12?h for 2?weeks starting on postnatal day 14 (n?=?27). Changes of retinal structure were monitored by confocal scanning laser ophthalmoscopy and spectral domain optical coherence tomography 12?h, 14?days, 4?weeks, 2?months, and 6?months after completion of the treatment. Results Schisis formation (peak at 3?months) preceded photoreceptor degeneration and hyper-fluorescence (peak at 7?months). Structural pathology was most severe in the superior hemi-retina with previously unreported hyper-fluorescent lesions. Quantitative analysis showed no significant differences regarding the inner or outer retinal thickness of the treated vs. untreated eyes 12?h after the completion of treatment (IRT(12?h) =?-1.29?±?1.89?μm; ORT(12?h) =?0.61?±?2.08?μm; mean?±?95%CI) or at any later time point. Conclusion Time line analysis after short-term treatment with CAI failed to show short-, intermediate-, or long-term evidence of structural improvement in Rs1h(-/y) mice. Schisis formation in the inner retina peaked at the age of 3?months and was followed by photoreceptor degeneration predominantly in the superior hemi-retina. Previously unreported hyper-fluorescent lesions co-register with structural retinal pathologies.  相似文献   
210.
ObjectiveTo determine the cardiovascular effects of a proprietary l-methadone/fenpipramide combination (Polamivet) alone and in addition to acepromazine in dogs.Study designProspective, randomized, experimental crossover study.AnimalsFive adult healthy Beagle dogs (one male and four females, weighing 12.8–16.4 kg).MethodsDogs were instrumented for haemodynamic measurements whilst anaesthetized with isoflurane. Three hours after recovery dogs received 0.025 mg kg?1 acepromazine (AP) or saline (SP) IM followed by 0.5 mg kg?1L-methadone/ 0.025 mg kg?1 fenpipramide IV after 30 minutes. Cardiac output using thermodilution, heart rate, mean arterial pressure (MAP), central venous pressure (CVP), mean pulmonary artery pressure (MPAP), pulmonary artery occlusion pressure (PAOP), haemoglobin concentration, arterial and mixed-venous blood gas analysis were measured and sedation evaluated at baseline (BL), 30 minutes after acepromazine or saline IM (A/S), 5 minutes after L-methadone/fenpipramide IV application (35), every 15 minutes for 1 hour (50, 65, 80, 95 minutes) and every hour until baseline cardiac output was regained. Standard cardiovascular parameters were calculated. Data were analyzed by repeated measures anova and paired t-tests with p < 0.05 considered significant.ResultsBaseline measurements did not differ. Cardiac index decreased after acepromazine administration in treatment AP (p = 0.027), but was not significantly influenced after l-methadone/fenpipramide injection in either treatment. In both treatments heart rate did not change significantly over time. Stroke volume index increased after A/S in both treatments (p = 0.049). Systemic vascular resistance index, MAP, CVP, MPAP, and pulmonary vascular resistance index did not change significantly after either treatment and did not differ between treatments. Dogs were deeply sedated in both treatments with a longer duration in treatment AP.Conclusions and clinical relevanceIn healthy dogs the dose of l-methadone/fenpipramide used in this study alone and in combination with acepromazine induced deep sedation without significant cardiovascular changes.  相似文献   
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