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A. C. B. YOUNG 《The Journal of small animal practice》1979,20(4):229-231
This paper reports two cases of torsion of a normal fully descended testicle in the dog, reviews the literature and discusses the pathogenesis of the condition. 相似文献
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Urinary methylmalonate excretion is increased in rats with an insufficiency of vitamin B(12). Excretion of methylmalonate is not affected by folic acid, vitamin E, or selenium, but is markedly decreased by small amounts of vitamin B(12) added to the diet. 相似文献
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A. J. STEVENSON M. P. WEBER R. TRUDEL R. LEAVITT‡ D. WOODARD‡ F. TODI M. MENDONCA V. ROBILLO L. YOUNG S. KACEW 《Journal of veterinary pharmacology and therapeutics》1994,17(3):163-168
Analytical procedures were developed to monitor furosemide concentrations in post-race serum and urine samples obtained from horses participating in an exercise-induced pulmonary haemorrhage (EIPH) program. High performance liquid chromatography with ultraviolet light detection proved a reliable, sensitive method for measuring urinary furosemide concentrations up to 12 h after administration of either 150 or 250 mg of the drug to race horses. However, this method was unreliable for determination of serum furosemide concentration. High performance liquid chromatography with fluorescence detection proved a reliable, sensitive method for measuring serum furosemide concentrations in horses administered 250 mg of the diuretic, permitting detection approximately 5–10 ng/ml 6 h after treatment. This method was applied field conditions where furosemide was administered to horses (between 150 and 250 mg intravenously) 4 h prior to the race. Analytical results assisted establishing a threshold concentration of 85 ng/ml for serum furosemide. was found that serum furosemide concentrations are a valid measure of compliance with furosemide administration in the EIPH program. 相似文献
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There is a need to simultaneously preserve evidence of interactions between the biological community and soil structural properties of a soil in as near an intact (natural) state as possible. Three dehydration techniques were implemented and assessed for their ability to minimise disruption of both biological and physical properties of the same arable soil sample. Dehydration techniques applied until samples were at constant weight were i) air-drying at 20℃ (AD); ii) -80 ℃ freeze for 24 h, followed by freeze-drying (-80FD); and iii) liquid nitrogen snap freeze, followed by freeze-drying (LNPD) and were compared to a moist control. Physical structure was determined and quantified in three dimensions using X-ray computed tomography and microbial phenotypic community composition was assessed using phospholipid fatty acid (PLPA) profiling. This study confirms that any form of dehydration, when preparing soil for simultaneous biological and physical analysis, will alter the soil physical properties, and cause some change in apparent community structure. Freeze-drying (both the LNFD and -80FD treatments) was found to minimise disruption (when compared to the moist control soil) to both the soil physical properties and the community structure and is a preferable technique to air-drying which markedly alters the size and character of the pore network, as well as the phenotypic profile. The LNFD was the preferred treatment over the -80FD treatment as samples show low variability between replicates and a fast turn-around time between samples. Therefore snap freezing in liquid nitrogen, followed by freeze drying is the most appropriate form of dehydration when two sets of data, both physical and biological, need to be preserved simultaneously from a soil core. 相似文献
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Measurements of the equation of state of deuterium at the fluid insulator-metal transition 总被引:1,自引:0,他引:1
GW Collins Da Silva LB P Celliers DM Gold ME Foord RJ Wallace A Ng SV Weber KS Budil R Cauble 《Science (New York, N.Y.)》1998,281(5380):1178-1181
A high-intensity laser was used to shock-compress liquid deuterium to pressures from 22 to 340 gigapascals. In this regime deuterium is predicted to transform from an insulating molecular fluid to an atomic metallic fluid. Shock densities and pressures, determined by radiography, revealed an increase in compressibility near 100 gigapascals indicative of such a transition. Velocity interferometry measurements, obtained by reflecting a laser probe directly off the shock front in flight, demonstrated that deuterium shocked above 55 gigapascals has an electrical conductivity characteristic of a liquid metal and independently confirmed the radiography. 相似文献
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