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1.
F F Farris A Poklis G E Griesmann 《Journal of the Association of Official Analytical Chemists》1978,61(3):660-663
A method is presented for determining lead in a variety of tissues. Lyophilized samples are solubilized with nitric acid at room temperature in glass screw-cap culture tubes. Following neutralization with sodium hydroxide and sodium bicarbonate, the lead is extracted into methyl isobutyl ketone as the pyrrolidine dithiocarbamate complex and analyzed by flame atomic absorption spectrophotometry. Brain, heart, liver, lung, and spleen gave recoveries ranging from 92 to 102% with standard deviations of less than 8%. Aorta, kidney, and rib were unsuitable for analysis by this method. A large number of samples can be analyzed without specialized equipment or intricate experimental steps. The detection limit is 35 ng/g tissue (wet weight) and sensitivity is approximately 140 ng/g tissue (wet weight). 相似文献
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The responses of the plasma concentrations of catecholamines and cortisol in horses to varied relative intensities of exertion were examined. The plasma concentrations of cortisol, epinephrine and norepinephrine increased significantly (p<0.05) with exertion. The plasma cortisol concentrations at relative work intensities of 48.3%±1.4%, 82.3%±2.0% and 99.6%±0.4% of VO2max were 114%, 124%, and 126%, respectively, of those at rest, whereas the plasma epinephrine concentrations were 239%, 772% and 3483%, and the norepinephrine concentrations were 138%, 255%, and 1121% of the values at rest. There was a significant (p<0.0001) relationship between the plasma epinephrine and norepinephrine concentrations. The blood lactate concentration and the plasma epinephrine and norepinephrine concentrations were significantly (p<0.0001) related, as were the relative work intensity (%VO2max) and the plasma epinephrine and norepinephrine concentrations. The relationships between the plasma cortisol concentration and work intensity or blood lactate concentration were not significant (p>0.05). This study demonstrates a relationship between relative work intensity and indicators of adrenal medullary and sympathetic activity during brief exertion in horses. 相似文献
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On a farm with therapeutic problems and unsatisfactory management conditions, the occurrence of antibiotic resistance and transferable antibiotic resistance has been studied in E. coli isolated from calves which were 5 and 30 days old. Strains with resistance to up to seven antibiotics as well as transferable resistance against up to five antibiotics were recorded. On an average, 4.2 strains with different patterns and 4.0 different strains with transferable resistance were isolated from each calf. The corresponding figures previously found for healthy control calves were 1.6 and 1.1 strains, respectively. Resistance and transferable resistance were most common against sulphonamide and penicillin. 相似文献
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Angioni A Caboni P Garau A Farris A Orro D Budroni M Cabras P 《Journal of agricultural and food chemistry》2007,55(5):2043-2048
The interaction of ochratoxin A (OTA) and 20 yeast strains of Saccharomyces cerevisiae and Kloeckera apiculata during alcoholic fermentation was studied. Levels of OTA were determined in the fermentation liquid and in the yeast cells solid using a high-performance liquid chromatography system with a fluorescence detector. Yeast cells do not adsorb OTA, and for all yeasts, OTA levels did not affect the alcoholic fermentation. Some yeast strains reduced levels of OTA, whereas other strains did not show any effect demonstrating that OTA level reduction is not a genus species characteristic but a strain trait. 相似文献
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Farris EJ 《Science (New York, N.Y.)》1932,75(1956):670-671
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Cabras P Farris GA Pinna MV Pusino A 《Journal of agricultural and food chemistry》2004,52(26):8053-8056
The fungicide fenhexamid [N-(2,3-dichloro-4-hydroxyphenyl)-1-methylcyclohexanecarboxamide] degraded rapidly by UV or sunlight irradiation, yielding 7-chloro-6-hydroxy-2-(1-methylcyclohexyl)-1,3-benzoxazole (CHB) as a main photoproduct. CHB was isolated, and its effect on alcoholic fermentation of Saccharomyces cerevisiae was studied. The results indicate that the presence of CHB does not affect the extent of alcohol production. After 12 days, the amount of CHB in the fermentation medium decreased by ca. 65%. Only 25% of the missing CHB was recovered unchanged from yeasts, most likely because it was adsorbed on the yeast wall cell. The remaining part degraded during the fermentation process. Glucan and chitin, two potential adsorbents, which constitute yeast cell walls, exhibited affinity for CHB. 相似文献
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Sefczek TM Farris ZJ Wright PC 《Folia primatologica; international journal of primatology》2012,83(1):1-10
In this research, we focused on aye-aye populations in Ranomafana National Park, Madagascar. From August to December 2008, we tested how aye-aye feeding was influenced by presence/absence of both fruiting and non-fruiting Canarium trees. Deadwood feeding traces were used as a proxy for evidence of Canarium feeding. We enumerated deadwood feeding traces in 20 locations, 10 with Canarium, 10 without. Each location contained two transects (80 m L × 20 m W) for a total area of 5.6 ha. Feeding trace results for Canarium locations compared to non-Canarium locations were not significant (Z = -1.926, p = 0.083); however, feeding trace results were significant when comparing fruiting and non-fruiting Canarium locations (Z = -2.417, p = 0.016). These results highlight the importance of Canarium in the diet of aye-ayes and demonstrate how the distribution of this resource may influence the foraging behavior of aye-ayes. 相似文献
10.
Robert Kr?ger Matthew T. Moore Jerry L. Farris Mathangi Gopalan 《Water, air, and soil pollution》2011,221(1-4):223-234
Typical controlled drainage structures in drainage ditches provide drainage management strategies for isolated temporal periods. Innovative, low-grade weirs are anticipated to provide hydraulic control on an annual basis, as well as be installed at multiple sites within the drainage ditch for improved spatial biogeochemical transformations. This study provides evidence toward the capacity of low-grade weirs for nutrient reductions, when compared to the typical controlled drainage structure of a slotted riser treatment. Three ditches with weirs were compared against three ditches with slotted risers, and two control ditches for hydraulic residence time (HRT) and nutrient reductions. There were no differences in water volume or HRT between weired and riser systems. Nutrient concentrations significantly decreased from inflow to outflow in both controlled drainage strategies, but there were few statistical differences in N and P concentration reductions between controlled drainage treatments. Similarly, there were significant declines in N and P loads, but no statistical differences in median N and P outflow loads between weir (W) and riser (R) ditches for dissolved inorganic phosphate (W, 92%; R, 94%), total inorganic phosphate (W, 86%; R, 88%), nitrate-N (W, 98%; R, 96%), and ammonium (W, 67%; R, 85%) when nutrients were introduced as runoff events. These results indicate the importance of HRT in improving nutrient reductions. Low-grade weirs should operate as important drainage control structures in reducing nutrient loads to downstream receiving systems if the hydraulic residence time of the system is significantly increased with multiple weirs, as a result of ditch length and slope. 相似文献