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91.
Simon RR Phillips KM Horst RL Munro IC 《Journal of agricultural and food chemistry》2011,59(16):8724-8732
This study compared the compositional changes in mushrooms exposed to sunlight with those occurring after commercial ultraviolet (UV) light processing. Button mushrooms (75 kg) were processed in the presence or absence of UVB light; a third group was exposed to direct sunlight. Mushroom composition was evaluated using chemical analyses. Vitamin D concentrations were 5, 410, and 374 μg/100 g (dw) in control, UVB, and sunlight groups, respectively. On a dry weight basis, no significant changes in vitamin C, folate, vitamins B(6), vitamin B(5), riboflavin, niacin, amino acids, fatty acids, ergosterol, or agaritine were observed following UVB processing. Sunlight exposure resulted in a 26% loss of riboflavin, evidence of folate oxidation, and unexplained increases in ergosterol (9.5%). It was concluded that compositional effects of UVB light are limited to changes in vitamin D and show no detrimental changes relative to natural sunlight exposure and, therefore, provide important information relevant to the suitability and safety of UVB light technology for vitamin D enhanced mushrooms. 相似文献
92.
Maria Fernanda de M. Costa Adriana K. Carmona Marcio F. M. Alves Timothy M. Ryan Helen M. Davies Garry A. Anderson Ron F. Slocombe 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(1):21-25
Angiotensin-I converting enzyme (ACE) is a key regulator of blood pressure, electrolytes and fluid homeostasis through conversion of angiotensin I into angiotensin II. Recently, a genetic polymorphism of the ACE gene, which accounts for 47% of the variation of ACE activity in blood, has been advocated as a biomarker of athletic aptitude. Different methods of analysis and determination of ACE activity in plasma have been used in human and equine research without a consensus of a "gold standard" method. Different methods have often been used interchangeably or cited as being comparable in the existing literature; however, the actual agreement between assays has not been investigated. Therefore, in this study, we evaluated the level of agreement between three different assays using equine plasma obtained from 29 horses. Two spectrophotometric assays using Furylacryloyl-phenylalanyl-glycyl-glycine as substrate and one fluorimetric assay utilizing o-aminobenzoic acid-FRK-(Dnp)P-OH were employed. The results revealed that the measurements from the different assays were not in agreement, indicating that the methods should not be used interchangeably for measurement of equine ACE activity. Rather, a single method of analysis should be adopted to achieve comparable results and critical appraisal of the literature is needed when attempting to compare results obtained from different assays. 相似文献
93.
Francis Zvomuya Francis J. Larney Walter D. Willms Ryan K. Beck Andrew F. Olson 《Strength and Conditioning Journal》2011,64(4):375-383
Landspraying while drilling (LWD) is an approved disposal method for water-based drilling mud (WBM) systems in western Canada. The mud is applied either on cultivated land, where it is incorporated by cultivation, or on vegetated land where it is not incorporated. This study examined the effects of summer WBM application (0, 15, 20, 40, and 80 m3 · ha?1) on native vegetation properties. Our results indicated that LWD increased bare ground but decreased lichen cover at the 80 m3 · ha?1 rate relative to the untreated control. Nitrogen (N), sulfur (S), and magnesium (Mg) concentrations in aboveground plant tissue increased with increasing LWD rate in samples taken 45 d after WBM application, but these differences disappeared 1 yr after treatment. Increase in tissue concentration of phosphorus (P) with LWD rate, however, was only detected 3 yr after LWD. Nonetheless, these changes in tissue chemistry were not associated with significant changes in biomass yield or species composition. Overall, our results suggest that single WBM applications at rates (≤ 20 m3 · ha?1) commonly used in western Canada, if properly managed, are unlikely to adversely affect native prairie vegetation. 相似文献
94.
Two adult female elf owls (Micrathene whitneyi) were treated with leuprolide acetate depot injections to prevent egg laying. The birds were treated for several years without complications. Several years into the treatment regimen, both birds died immediately after receiving an injection of leuprolide acetate. Remaining drug was analyzed, revealing 95.7% potency. We suspect that either an immediate Type 1 hypersensitivity reaction occurred or a contaminant was present, resulting in the fatalities of these elf owls. No reports of anaphylaxis to leuprolide acetate in birds were identified in the literature. Clinicians should be aware of the possibility of anaphylaxis when administering this medication to avian patients. 相似文献
95.
Three sexually mature female common vampire bats (Desmodus rotundus) housed at the North Carolina Zoological Park, Asheboro, North Carolina, were selected for surgical ovariohysterectomy. All animals were induced and maintained with isoflurane anesthetic gas. Magnification loop glasses were worn by the surgeon for the procedure. A ventral midline incision was made into the abdominal cavity. Simple micro-ophthalmic surgical packs along with hemoclips were used to perform the ovariohysterectomies. The linea alba and muscular layers were closed using a simple continuous suture pattern with 4-0 polydioxanone suture. The skin was apposed using a horizontal mattress suture pattern with 4-0 polydioxanone suture. Animals recovered with minimal deleterious side effects. Animals were housed together in a recovery chamber and administered meloxicam at 0.2 mg/kg placed in their blood meal once daily for 7 days postoperatively, after which they were returned to their normal enclosures. 相似文献
96.
Soil structure heterogeneity in the form of macropores and preferential flow channels can complicate efforts to quantify the physical and biological characteristics of wetland systems. We collected soil cores from two riparian wetlands to determine whether soil associated with macropores had elevated denitrification potentials compared to bulk soil from the same core. Cores were inspected for obvious macropores, which were distinguished as visible holes in the core, sometimes with decaying root matter, or as highly unconsolidated layers that appeared to have a substantially lower bulk density than the surrounding soil. Denitrification potentials were significantly higher in pores (P<0.05) for six of the 16 cores that were obtained from the Cheraw State Park site. In cores obtained from a second site, denitrification potentials were significantly higher in pores for six of 20 cores and the trend of higher denitrification in pores was present in the majority of cores that had measurable activity. In cores with significant differences, denitrification was often 1-2 orders of magnitude greater in soil surrounding the macropore than in the bulk soil. Denitrification potentials of the bulk soils were similar in magnitude to the potentials measured in composited cores from previous studies. It is possible that the difference between macropore and bulk denitrification rates developed due to preferential flow of nitrate-rich water through the macropores. Previous work showed that water entering these riparian systems in groundwater and storm runoff had elevated levels of NO3−. 相似文献
97.
Under semi-arid Mediterranean conditions, limited moisture is the main constraint to rainfed cropping with wheat (Triticum aestivum), barley (Hordeum vulgare), and food and forage legumes. With increasing land-use pressure, moisture-conserving fallowing is being replaced by continuous cropping, which is considered an unsustainable practice. Thus, a long-term trial with durum wheat (T. turgidum var. durum) was established in 1983 at Tel Hadya, Aleppo, Syria (mean annual rainfall 330 mm) to assess alternative rotation options to fallow and continuous cropping. Nitrogen (N) and grazing/residue management were secondary factors. Soil aggregation, infiltration, hydraulic conductivity, and total soil organic matter and component fractions (fulvic and humic acids and polysaccharides) were determined at the end of 12 years. Some rotations, e.g., medic (Medicago sativa) and vetch (Vicia faba), significantly increased soil organic matter (12.5–13.8 g kg−1 versus 10.9–11 g kg−1 for continuous wheat and wheat/fallow). All measurements, or indices, indicated parallel trends with increasing organic matter, e.g., coefficients of macro-structure, micro-aggregation, and water-stable aggregates, and decreasing dispersion. Similarly, legume rotations had higher infiltration rates (16.2–21.8 cm h−1 versus 13.9–14.4 cm h−1 with continuous wheat and wheat/fallow) and hydraulic conductivity rates (8.7–12.4 cm h−1 versus 6.2–7.4 cm h−1 with continuous wheat and wheat/fallow). We conclude that cereal/legume rotations, in addition to being biologically and economically attractive, also enhance soil quality and thus promote soil use sustainability in fragile semi-arid areas as in the Mediterranean zone. 相似文献
98.
Brent?A.?CoullEmail author Maura?Mezzetti Louise?M.?Ryan 《Journal of Agricultural, Biological & Environmental Statistics》2003,8(3):253-270
This article uses a Bayesian hierarchical model to quantify the adverse health effects associated with in-utero exposure to
methylmercury. By allowing for study-to-studyas well as outcome-to-outcome variability, the approach provides a useful meta-analytic
tool for multi-outcome, multi-study environmental risk assessments. The analysis presented here expands on the findings of
a National Academy of Sciences (NAS) committee, charged with advising the United States Environmental Protection Agency (EPA)
on an appropriate approach to conducting a risk assessment for methylmercury. The NAS committee, for which the senior author
(Ryan) was a committee member, reviewed the findings from several conflicting studies and reported the results from a Bayesian
hierarchical model that synthesized information across several studies and for several outcomes. Although the NAS committee
did not suggest that the hierarchical model be used as the actual basis for a methylmercury risk assessment, the results from
the model were used to justify and support the final recommendation that the risk analysis be based on data from a study conducted
in the Faroe Islands, which had found a positive association between in-utero exposure to methylmercury and impaired neurological
development. We considera variety of statistical issues, but particularly sensitivity to model specification. 相似文献
99.
100.
Bovine spongiform encephalopathy: aspects of the clinical picture and analyses of possible changes 1986-1990. 总被引:1,自引:0,他引:1
A standard questionnaire was used to record the presence of specific clinical signs reported for histopathologically confirmed cases of bovine spongiform encephalopathy observed before June 30, 1990, and the frequencies of these signs were analysed. The signs most frequently recorded were apprehension, hyperaesthesia and ataxia, and there were variations in the frequency with which some signs were recorded in animals observed at different times during the epidemic. These variations were considered to be the result of differences between observers and differences in the duration of the illness, rather than a change in the clinical picture, which could possibly have occurred with a change in the nature of the agent to which the cattle had been exposed, or to a change in their response to the agent. 相似文献