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1.
Sulfamethazine was administered to 8- to 10-week-old turkey poults intravenously (IV) at the dose level of 71.5 mg/kg of body weight, orally at the dose level of 143 mg/kg of body weight, or in the drinking water at the concentration of 0.1% over a 6-day period. The concentrations of free sulfamethazine in blood, muscle, skin, kidney, and liver were determined and semilogarithmic plots of concentration vs time for the various tissues indicated that the curve had a linear portion within the first 72-hour period of drug withdrawal. The rates of disappearance of sulfamethazine from the various tissues were proportional to the concentration in the tissues. After 72 hours of withdrawal and for as long as 14 days, sulfamethazine concentrations in kidney, liver, and skin of turkeys given the drug in the drinking water fluctuated between 0.1 and 0.4 ppm. Only 8.6% of the oral dose (143 mg/kg) and 16.5 to 17% of the IV dose (71.5 mg/kg) were recovered in urine and feces as the parent compound during the initial 72-hour period.  相似文献   
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The aim of this study was to test the influence of post ‐ thaw storage time on the duration of sperm motility, percentage of motile sperm, and fertilization and hatching rates of fresh sperm and sperm stored for 0, 30 and 60 min at 4°C post‐thawing. After being frozen in liquid nitrogen and then thawed, the percentage of motile sperm and duration of motility were not affected by 30 min of storage at 4°C, whereas a significant decline in these parameters was observed after 60 min of storage. Similarly, fertilization and hatching rates were significantly affected within 60 min of storage at 4°C, and the fertility of frozen‐thawed sperm was significantly lower than that of fresh sperm. We conclude that cryopreserved sperm of beluga sturgeon could be stored for 30 min without the loss of sperm quality. This described procedure for beluga sturgeon cryopreservation is reliable and efficient and therefore can be recommended for hatchery practice after scaling up this technique.  相似文献   
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Two cases of Rhodococcus equl infection in foals are described, in which osteomyelitis was a feature. Because rhodococcal infection is usually low grade and chronic, and because the signs of early metaphysitis can be subtle, any articular or periarticular swelling in a foal from a farm with a history of rhodococcosis should be strongly suspected to be associated with R equl until proven otherwise.  相似文献   
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Jupiter's moon Io is known to host active volcanoes. In February and March 2007, the New Horizons spacecraft obtained a global snapshot of Io's volcanism. A 350-kilometer-high volcanic plume was seen to emanate from the Tvashtar volcano (62 degrees N, 122 degrees W), and its motion was observed. The plume's morphology and dynamics support nonballistic models of large Io plumes and also suggest that most visible plume particles condensed within the plume rather than being ejected from the source. In images taken in Jupiter eclipse, nonthermal visible-wavelength emission was seen from individual volcanoes near Io's sub-Jupiter and anti-Jupiter points. Near-infrared emission from the brightest volcanoes indicates minimum magma temperatures in the 1150- to 1335-kelvin range, consistent with basaltic composition.  相似文献   
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Stratospheric temperatures on Saturn imply a strong decay of the equatorial winds with altitude. If the decrease in winds reported from recent Hubble Space Telescope images is not a temporal change, then the features tracked must have been at least 130 kilometers higher than in earlier studies. Saturn's south polar stratosphere is warmer than predicted from simple radiative models. The C/H ratio on Saturn is seven times solar, twice Jupiter's. Saturn's ring temperatures have radial variations down to the smallest scale resolved (100 kilometers). Diurnal surface temperature variations on Phoebe suggest a more porous regolith than on the jovian satellites.  相似文献   
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Jupiter's main ring shows vertical corrugations reminiscent of those recently detected in the rings of Saturn. The Galileo spacecraft imaged a pair of superimposed ripple patterns in 1996 and again in 2000. These patterns behave as two independent spirals, each winding up at a rate defined by Jupiter's gravity field. The dominant pattern originated between July and October 1994, when the entire ring was tilted by about 2 kilometers. We associate this with the Shoemaker-Levy 9 impacts of July 1994. New Horizons images still show this pattern 13 years later and suggest that subsequent events may also have tilted the ring. Impacts by comets or their dust streams are regular occurrences in planetary rings, altering them in ways that remain detectable decades later.  相似文献   
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The double-isotope single-injection method to estimate renal function which utilizes the radiolabeled chemicals [131I]sodium iodohippurate and [125I]sodium iothalamate was evaluated in swine. A total of 46 normal, cross-bred swine were used to determine the applicability of this method for measuring the glomerular filtration rate and effective renal plasma flow. The mean glomerular filtration rate in pigs was determined to be 5.33 +/- 0.82 ml/kg of body weight/minute for [125I]sodium iothalamate with a biological half-life (T 1/2) of 39.18 +/- 7.44 minutes. The mean effective renal plasma flow was determined to be 19.25 +/- 3.12 ml/kg of body weight/minute for [313I]sodium iodohippurate, with a T 1/2 of 18.45 +/- 1.74 minutes. These values are more closely related to the glomerular filtration and effective renal plasma flow values reported for dogs and cats than they are to values reported for man. The method is rapid and reliable; results are available 6 to 8 hours after the experiment. This method is advantageous when information about renal function variables is a prerequisite to pharmacokinetic or toxicologic studies.  相似文献   
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