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11.
To test the hypothesis of a heritable base of ectopic ureters (EU) in Entlebucher Mountain Dogs (EMD) and to elucidate associated risk factors and mode of inheritance of the disease, 565 EMD were clinically investigated and population genetic analyses performed. Based on the location of the most caudal termination of the ureteral openings, 552 EMD were classified into three phenotype groups trigone, intravesically and extravesically ectopic based on results of abdominal sonography, urethra‐cystoscopy and/or contrast‐enhanced computed tomography. One‐third (32.9%) of the phenotyped animals had normal terminations of both ureters in the bladder trigone, 47.3% had at least one intravesicular ectopic termination and 19.8% had at least one extravesicular ectopic termination. Multivariate mixed logistic regression revealed gender as a risk factor associated with EU as males were more often affected than females. Complex segregation analysis indicated a hereditary basis for EU in EMD and the involvement of a major gene in the occurrence of the extravesicular EU phenotype.  相似文献   
12.
Effect of vitamin E and selenium on iron utilization in neonatal pigs.   总被引:7,自引:0,他引:7  
Supplying adequate iron (Fe) to neonatal pigs to support normal growth and hematological and antioxidant status, while preventing iron toxicity, is a challenge for producers. Three experiments were conducted to determine the effect of frequency and route of Fe administration with or without vitamin E (E) and selenium (Se) on growth, Fe, and antioxidant status of neonatal pigs. In Exp. 1, 12 pigs from dams with reduced E status were fed a semipurified diet without added Fe from d 3 to d 14 of age. At d 6 of age, pigs received the following i.m. injections: 1) FE, 1 mL containing 200 mg of Fe (iron dextran); 2) FEE, treatment FE plus 1 mL containing 300 IU of vitamin E (d-alpha tocopherol); or 3) FESEE, 1.03 mL containing 200 mg of Fe (iron dextran), .15 mg of Se (sodium selenite), and 15 IU of vitamin E (d-alpha tocopherol). Pigs were weighed daily and blood was collected at 3, 7, and 14 d of age. From d 8 to 14, growth was depressed (P < .05) in pigs injected with FESEE. At 14 d of age, pigs injected with FE or FEE had increased (P < .05) hemoglobin (Hb) concentration. Ceruloplasmin activity (CP) was greater (P < .05) at d 7 of age than at d 3 or 14 regardless of treatment. In Exp. 2, 3-d-old pigs (n = 94) received the following: 1) FE, 200 mg Fe (iron dextran) i.m.; (2) FEE, treatment FE plus 300 IU vitamin E i.m.; 3) EFE, 300 IU vitamin E i.m. followed by 200 mg Fe (iron dextran) i.m. 24 h later; or 4) OFE, 100 mg Fe and 10 mg Cu orally. On d 21 of age, one-half of the pigs in each treatment received a second dose of their respective treatment. Blood samples (n = 60) were obtained on d 3 and 21 of age. Pigs injected with FE, FEE, or EFE had greater (P < .05) Hb at d 21 than pigs given OFE. Copper/zinc superoxide dismutase (Cu/ZnSOD) activity was greater (P < .05) at d 21 with OFE than with the other treatments. At 65 d of age, ADG did not differ among treatments. In Exp. 3, pigs (n = 150, in three farrowing groups) were injected with 200 mg of Fe (iron dextran) on d 1 or d 1 and 14. Blood samples were obtained on d 7 and 21 of age. Hemoglobin concentration on d 21 was improved equally by both treatments. Catalase and Cu/ZnSOD activities were increased (P < .05) on d 21 of the experiment compared with d 7 regardless of treatment. Growth was not affected by injection frequency. Results from these experiments indicate that one Fe injection (200 mg) for pigs from sows fed adequate vitamin E will result in adequate growth and hemoglobin concentration with today's improved genetics.  相似文献   
13.
Ventral aortic blood pressure (Pva) and heart rate (HR) responses to rapidly (within 1 min) induced hypoxia (PWO2=4−5.3 kPa) were investigated in vivo in three species of marine teleosts (shorthorn sculpin, Myoxo-cephalus scorpius; eel-pout, Zoarces viviparus; and five-bearded rockling, Ciliata mustela). Fish were exposed to hypoxia for 4 min (M.scorpius) or 5 min (Z.viviparus and C.mustela). Pva was unaffected in M.scorpius, decreased in Z.viviparus and increased in C.mustela in response to hypoxia. Untreated M.scorpius and Z. viviparus responded with a characteristic bradycardia during hypoxia, whereas C.mustela developed no bradycardia. Injection of atropine followed by the β-adrenoceptor antagonist sotalol in M.scorpius and Z. viviparus, revealed that both the inhibitory (cholinergic) and the excitatory (adrenergic) influence on the heart increase during hypoxia. The inhibitory influence dominates, resulting in the observed bradycardia.  相似文献   
14.
Coatings of biomaterials or implants that facilitate biomineralization possess a great potential for applications focused to the replacement, augmentation, and regeneration of bone tissue. Biomimetic approaches utilize biomolecules for either templating or supporting the crystallization process. One of these promising biomolecules is phosvitin (PV), an egg yolk protein known to transport and store inorganic phosphates and calcium ions. The incorporation of PV into polyelectrolyte multilayers is favorable due to PVs high degree of phosphorylation and thus a high acidity. Utilizing the reflectometric interference spectroscopy, the adsorption kinetics of this novel polyelectrolyte system composed of poly-L-lysine and the heavily phosphorylated phosvitin were monitored. The results demonstrate an unexpected nonregular growth regime called overshoot. Effective measures of shifting this irregular polyelectrolyte adsorption process back to a regular multilayer growth regime are reported in this paper.  相似文献   
15.
It is known that in wetland soils and soils contaminated with mercury (Hg), direct biotic reduction of Hg2+ to Hg0 leads to Hg0 emissions to the atmosphere. In terrestrial soils, numerous factors have been reported that control Hg0 emissions, but it is still unclear if biotic processes are also important. In this study, microbiological activity of Cambisol monoliths from a subalpine grassland with Hg concentrations of approx. 100 ng g–1 were manipulated in laboratory incubation experiments. Elemental Hg emissions were recorded together with CO2 emission rates as proxy for microbiological respiration. Emissions of Hg0 increased from approx. 5 ng m–2 h–1 up to 130 ng m–2 h–1 with stimulated biological activity (glucose addition, increase in temperature) and decreased with inhibited activity (chloroform fumigation, autoclaving, drying). Similar patterns with evasion rates of >90 ng m–2 h–1 were observed after dried soils were remoistened again. Our results indicated that processes leading to Hg0 emissions from uncontaminated terrestrial soils are at least partly controlled by biotic processes. However, it is still uncertain if Hg0 emission is caused directly by biotic reduction of Hg2+ or indirectly by abiotic reduction, induced by products of microbiological degradation, e.g., humic acids.  相似文献   
16.
Biotin deficiency in animals causes pathological changes of the skin and its appendages including, for example, exfoliative dermatitis, depigmentation, and alopecia. The hooves of biotin-deficient swine are weak, brittle, and often necrotic. These changes disappear after dietary biotin supplementation. Biotin supplementation also noticeably improves the hoof quality of horses, cattle and swine having no apparent biotin deficiency. In order to elucidate the molecular basis of these effects, the influence of biotin on cytokeratin expression in a keratinocyte cell line (Ha-CaT) was investigated using electrophoretic and immunological techniques. Pharmacological biotin concentrations of 1 microM, and 100 microM in the culture medium caused a specific increase in cytokeratins, which are normally induced upon terminal differentiation of epidermal cells in vivo. The expression of cytokeratins occurring in stratified epithelia independent of differentiation were not affected. These findings show that biotin directly stimulates the differentiation of epidermal cells. Such a molecular mechanism revealed in cell culture could provide an explanation for the therapeutic effects of pharmacological doses of biotin on hoof quality in farm animals.  相似文献   
17.
The conversion of even-aged Norway spruce (Picea abies (L.) H. Karst.) stands into more site adapted mixed stands is the main silvicultural goal in Germany and many other European countries. The conversion will primarily be achieved with the help of selection cutting, removing single target diameter trees and creating small gaps. At sites highly susceptible to windthrow, however, small scale clear cutting (up to 1 ha) might be an appropriate alternative. Both selection and clear cutting will affect the understorey vegetation, an important component of forest biodiversity and ecosystem functioning. Thus, with the help of a BACI-experiment (before–after/control–impact), the short-term effects of selection and small scale clear cutting on the herb and shrub layer vegetation were studied at two sites in the Solling Hills (Lower Saxony, Germany). Both treatments led to an increase in herb and shrub layer species numbers, due to persistent and invading (mainly pioneer tree species and indicators of disturbance) species and to a shift in plant traits. Most responsible for the changes in vegetation was a higher light availability, and to a lesser degree soil disturbance. The number of annuals and ruderals, however, increased only immediately after clear cutting, whereas on selection cutting plots the numbers remained high. Gaining in number and coverage were competitive perennials (Epilobium angustifolium, Juncus effusus, Rubus idaeus) especially on the clear cuttings, fulfilling a nutrient retention function. The competitives did not deter tree species from regenerating in the clear cut plots, whereas on selection cutting plots the large expansion of R. idaeus appeared to be hindering tree colonisation. Suffering under clear cut conditions were predominantly shade-tolerant, closed-forest species, but no loss of these species could be detected. This indicates the potential for a fast recovery of these forest species, as soon as, pioneer trees expand.  相似文献   
18.
19.
Consistent evidence suggests that the probable human carcinogen acrylamide is formed in starch-rich foodstuffs through heat-induced interaction of asparagine and reducing sugars during Maillard browning. However, information regarding the influence of processing parameters on acrylamide formation is scarce. We investigated the impact of temperature, heating time, browning level, and surface-to-volume ratio (SVR) on acrylamide generation in fried potatoes. Acrylamide content was determined by liquid chromatography (LC) and electrospray ionization tandem mass spectrometry (ESI-MS/MS). In potato shapes with low SVR, acrylamide content consistently increased with increasing temperature and processing times. By contrast, in shapes with intermediate to high SVR, maximal acrylamide formation occurred at 160-180 degrees C, while higher temperatures or prolonged processing times caused a decrease of acrylamide levels. Moreover, browning levels were not a reliable measure of acrylamide content in large-surface products.  相似文献   
20.
Three monovarietal extra virgin olive oils (EVOOs) were subjected to accelerated storage conditions (60 degrees C, dark) representative of the autoxidation process during shelf life. Oxidation markers, i.e., the peroxide value, conjugated dienes, the oil stability index, and minor components, were monitored. The changes in minor components, related to the stage of ongoing oxidation and expressed as a percentage of the induction period (IP), followed a similar pattern in all oils: o-diphenols diminished by the highest rate (halved within 15% of the IP), followed by alpha-tocopherol (halved within 35% of the IP). Carotenoids and chlorophylls were also affected by autoxidation, whereas squalene showed high stability (<20% loss within 100% of the IP). Polar phenols (especially o-diphenols) and alpha-tocopherol were deduced to be the most potent antioxidants of EVOO. They efficiently inhibited oxidative lipid deterioration and subsequent development of sensory defects (rancidity, discoloration), which occurred only after substantial depletion of these antioxidants. Therefore, they could also be used as markers for the oxidative status of EVOO particularly in the early stage of oxidation.  相似文献   
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