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121.
Paolo  Porzio  DVM  MVetSc  John W.  Pharr  DVM  MS  Andrew L.  Allen  DVM  MVetSc  PhD 《Veterinary radiology & ultrasound》2001,42(3):238-243
There are many indications for an intravenous excretory urogram. However, where intravenous access is not available, the intraosseous route to the circulation may be an alternative. We found that safe and diagnostic excretory urograms could be obtained in rabbits following the injection of different contrast media via the intraosseous route. In fact, these excretory urograms were indistinguishable from ones obtained by the conventional intravenous route. While the rabbits did not develop any abnormal clinical signs following the procedure, there were postmortem histologic lesions of osteochondrosis in 5 of 22 (22.7%) tibias receiving an intraosseous needle, but in none of the 14 tibias that did not receive an intraosseous needle. Further, the use of diatrizoate was associated with the development of osteochondrosis while the use of iopamidol was not.  相似文献   
122.
Production characteristics of channel catfish (Ictalurus punctatus) reared in cages and open ponds were compared. Fish reared in open ponds had significantly better growth and food conversion ratios than fish reared in cages. Cages and open ponds stocked with fish which were closely graded in size produced fish with less size variability at harvest compared to ponds and cages stocked with nongraded and coarsely graded fish. The decrease in size variability at harvest was reflected in a greater proportion of marketable fish.  相似文献   
123.
Oxidative damage plays an important role in the pathophysiology of diabetes and diabetic complications. Feline hemoglobin is uniquely susceptible to oxidative denaturation; therefore, Heinz body formation is a highly sensitive indicator of in vivo oxidative stress in this species. Heinz bodies also contribute to anemia. We investigated hematological and clinical biochemical changes in 30 cats with spontaneous diabetes mellitus (as compared to 15 healthy control cats) and evaluated the relationship of these changes to erythrocyte oxidative damage. Cats were categorized as ketoacidotic or nonketoacidotic based on their clinical presentation and the presence of urine ketones. Ketoacidotic cats had significantly ( P = .0009) more Heinz bodies (28.3% ± 9.1 %) than nonketotic diabetic cats (6.5% ± 1.60%) and healthy control cats (0.6% ± 0.2%). Percent Heinz bodies in diabetic cats directly correlated with plasma β-hydroxy-butyrate concentration ( r = .622; P = .0002), as well as with serum chloride concentration ( r = -0.576; P = 0.0009) and the number of monocytes ( r = .536; P = .0023). Percent Heinz bodies were negatively correlated with erythrocyte glutathione concentrations. Erythrocyte membrane lipid peroxidation was slightly but not significantly increased in diabetic cats. There were no significant associations between percent Heinz bodies and degree of anemia, hyperglycemia, or glycohemoglobin. These data indicate that ketones are associated with oxidative hemoglobin damage in cats, and suggest that ketone metabolism, ie by cytochrome P450 2E1, may be a potential source of in vivo oxygen radical generation in animals with ketosis.  相似文献   
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Mink with Aleutian disease developed severe anemia within a few months after infection. Evaluation of erythropoiesis and erythrocyte survival demonstrated that the anemia was caused by increased erythrocyte destruction, complicated in some cases by decreased or inadequate erythropoiesis. An inverse relationship existed between the amount of IgG on affected mink erythrocytes and the erythrocyte half-life. However, the number of IgG molecules/erythrocyte were not high enough to be detected by direct Coombs' test, with the exception of one case. Inadequate erythropoiesis was reflected by lower plasma iron turnover levels and reticulocyte numbers than expected considering the severity of the anemia involved.  相似文献   
127.
SONOGRAPHY OF THE EQUINE PALMAR METACARPAL SOFT TISSUES   总被引:2,自引:0,他引:2  
It was hypothesized that ultrasonography may be a sensitive method for identifying pathologic changes in the tendons and ligaments of the palmar metacarpus of the horse. The palmar meta-carpi of equine cadavers and live horses were examined sonographically. The advantages and disadvantages of various ultrasound scanning techniques and the normal appearance of longitudinal and transverse palmar metacarpal sonograms are described.  相似文献   
128.
The degradation of pirimiphos-methyl on grains stored at moisture contents of ≈ 13 and ≈20% has been investigated. Wheat and rice grains were sprayed with [14C]- pirimiphos-methyl and stored at 20°C under controlled humidity conditions for periods of 12 and 24 weeks. At a moisture content of 13%, degradation was slow, so that at least 70% of the radioactive residue was unchanged pirimiphos-methyl after 24 weeks. Faster degradation occurred at 20% moisture content, but the major component of the radioactive residue (at least 52%) was still unchanged pirimiphos-methyl after 24 weeks. Two major degradation products were formed on the grains; one (18–23.4% of the residue) was characterised as 2-diethylamino-6-methyl-pyrimidin-4-ol, and the other (1.0–9.7% of the residue) was converted to the first by acid hydrolysis. In addition, trace amounts of O-2-ethylamino-6-methyl-pyrimidin-4-yl OO-dimethyl phosphorothioate, 2-ethylamino-6-methyl-pyrimidin-4-ol, 2- amino-6-methyl-pyrimidin-4-ol and an unidentified compound were also detected.  相似文献   
129.
The effects on root geotropism of three series of compounds related to 2-phenyl-8H-pyrazolo[5,1-a]isoindol-8-one (IV), its 3,3a-dihydro derivative (V) and 5-(2-carboxyphenyl)-3-phenylpyrazole (VI) have been assessed using cress seedlings. Compounds (IV) and (VI), and their derivatives, are highly active, destroying geotropism at concentrations of 10?7-10?9M. Substitution with various functional groups and increased molecular size resulted in only minor variation in the level of activity.  相似文献   
130.
Peripheral alpha- and beta-adrenergic control of uterine blood flow (UBF) during acute heat stress of the gravid ewe was investigated. An electromagnetic blood flow probe was surgically implanted around the left miduterine artery and catheters inserted in the left carotid artery and right jugular vein in ewes between d 120 and 130 of gestation. Four or more days postsurgery, ewes were fitted with instruments to measure rectal temperature (Tr), heart rate (HR), respiratory rate (RR), blood pressure (BP) and UBF. One-half hour after instrument calibration, a 15-min thermoneutral control period was initiated with carotid artery blood samples taken at 5-min intervals for pH and PCO2 determinations. Ewes were then subjected to a heat challenge that reached 40 C at 2 h. All physiological data were recorded every 5 min as 1-min mean values. In seven experiments on five ewes, an alpha-adrenergic blocking drug, phenoxybenzamine (PB) was infused at 1 mg/min for 15 min subsequent to maximum depression of UBF. A beta-adrenergic blocking drug, propranolol (PR) was infused at .35 mg/min for 15 min in eight experiments on five ewes. Analysis of variance comparisons were made between the control period and heat stress infusion periods within the PB and PR experiments. Further comparisons were made between the start and 5, 10 or 15 min of PB or PR infusion in order to test drug effects during an acute heat stress. Rectal temperature HR, RR and arterial pH were higher (P less than .05) at the start of PR and PB infusions than during the thermoneutral control period.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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