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111.
DAVID G. LEVINE BETH M. ROSS MICHAEL W. ROSS DEAN W. RICHARDSON BENSON B. MARTIN 《Veterinary radiology & ultrasound》2007,48(5):467-470
Decreased radiopharmaceutical uptake, photopenia, in delayed phase scintigraphic images is recognized in people but has only been reported rarely in horses. We describe three horses with septic osteitis, bone sequestrum formation, or distal limb thrombosis that had photopenia of the affected extremity. Photopenia may indicate the presence of ischemia and can be used to facilitate clinical decision making and prognosis assessment 相似文献
112.
113.
STEPHEN JOSLYN MARTIN SULLIVAN ROSA NOVELLAS NICOLA BRENNAN GILL CAMERON GAWAIN HAMMOND 《Veterinary radiology & ultrasound》2011,52(6):611-618
A delay in imaging following intravenous contrast medium administration has been recommended to reduce misdiagnoses. However, the normal variation of contrast enhancement in dogs following a delay has not been characterized. Contrast‐enhanced MR imaging of 22 dogs was assessed, in terms of identification of normal anatomic structures, to investigate the variation associated with 10‐min delay between contrast medium administration and imaging. All dogs had a normal brain MR imaging study and unremarkable cerebrospinal fluid. Specific regions of interest were assessed both objectively, using computer software, and subjectively using three observers. Mean contrast enhancement >10% was seen in the pituitary gland, choroid plexus, meninges, temporal muscle, trigeminal nerve, and the trigeminal nerve root. Structures with an active blood–brain barrier had minimal contrast enhancement (<6%). Enhancing structures had significantly more contrast enhancement at t=1 min vs. t=10 min, except in temporal muscle, the trigeminal nerve and the trigeminal nerve root. Interobserver agreement was moderate to good in favor of the initial postcontrast T1‐weighted (T1w) sequence. The observers found either no difference or poor agreement in identification of the nonvascular structures. Intraobserver agreement was very good with all vascular structures and most nonvascular structures. A degree of meningeal enhancement was a consistent finding. The initial acquisition had higher enhancement characteristics and observer agreement for some structures; however, contrast‐to‐noise was comparable in the delayed phase or not significantly different. We provide baseline references and suggest that the initial T1w postcontrast sequence is preferable but not essential should a delayed postcontrast T1w sequence be performed. 相似文献
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115.
DAVID GELA MARTIN FLAJŠHANS MARTIN KOCOUR MAREK RODINA OTOMAR LINHART 《Aquaculture International》2006,14(1-2):195-203
A basic assumption for carrying out the breeding work is to have well-organised broodstock management. Taking into account
the number of populations bred and the limited number of ponds available, it is impossible to avoid rearing several juvenile
or adult breeds in mixed stocks. Fish of individual breeds are group-marked with regular renewal of the freeze-branded mark
and broodstock adults should be marked individually. To minimise inbreeding or losses in genetic variation, at least 120 fish
per strain are reared and when the strain is restored, factorial crosses of at least 15 females and 25 males should be applied.
All activities are individually registered in the “Evidence 2003” data-recording software and data can be sorted by the origin
of the fish population, of the strain or of individual fish; reproductive and performance parameters are recorded individually
also. Further breeding operations with tench comprise the selection after over-wintering and rearing of fish before, during
and after the reproductive season. 相似文献
116.
Various procedures for artificial insemination in tench, Tinca tinca (L.) were re-examined with evaluation of fecundity of males and females among different tench strains. The objectives of
this study were to enhance fertilization and hatching rates through optimization of the activation solution, the insemination
process, the activation of gametes, and the elimination of eggs stickiness. Sperm for all experiments was collected directly
into immobilization solution of modified Kurokura solution containing 180 mM of NaCl and stored at 2 °C for 2.5–5 h prior
to the experiment. When dechlorinated tap water was used for activation a gamete ratio of 1150 spermatozoa per egg showed
the best significant fertilisation and hatching rates. Optimal ratio between eggs (weight in g) and activation solution (in
cm3) was 1:1. Different concentrations of activation solutions such as NaCl from 0 to 68 mM (0–136 mOsmol kg−1) without buffer statistically decreased fertilization and hatching rates. The activation solution containing 17 mM of NaCl,
10 mM Tris–HCl, pH 8 and 9 significantly increased fertilization and hatching rates compared to dechlorinated tap water of
pH 7 or activation solution containing 17 mM of NaCl, 10 mM Tris–HCl, pH 6 and 7. Adhesiveness of the eggs was successfully
removed by incubation in Alcalase and activity: 3.16 Anson units per cm3. 相似文献
117.
118.
B. W. HOWARD DVM M. S. LAGUTCHIK DVM A. J. JANUSZKIEWICZ PhD D. G. MARTIN DVM PhD Diplomate ACLAM 《Veterinary surgery : VS》1990,19(6):461-467
Butorphanol tartrate (0.5 mg/kg intravenously [IV]) was administered to six ewes (group 1), 10 minutes before administration of tiletamine-zolazepam (12 mg/kg IV). In six ewes (group 2), butorphanol tartrate and tiletamine-zolazepam were administered simultaneously. Time of administration of butorphanol did not alter hemodynamics or duration of anesthesia significantly. Anesthesia was adequate for 25 to 45 minutes (mean, 31 min) in group 1. The sheep in group 2 were anesthetized effectively for 25 to 50 minutes (mean, 39 min). Neither dosing regimen caused significant changes in right atrial pressure, heart rate, pulmonary vascular resistance, or pulmonary capillary wedge pressure. Mean arterial blood pressure (MABP) decreased an average of 18% from baseline values of 113 mm Hg to a minimum of 84 mm Hg at minute 60 in group 1, and from 111 mm Hg to 92 mm Hg at minute 75 in group 2. The decrease was significant only for group 1. Cardiac output (CO) was significantly decreased 24% from 6.6 L/min at minute 45 in group 1, and 32% from 6.3 L/min at minute 15 in group 2. Systemic vascular resistance (SVR) was increased significantly at minute 15, 11% in group 1 and 37% in group 2. Mild respiratory acidosis was measured by significant decreases in arterial pO2 and pH and a significant increase in pCO2 without significant changes in HCO3-. Results of this study show that (1) tiletamine-zolazepam and butorphanol tartrate produce adequate anesthesia for 25 to 50 minutes; (2) the cardiovascular and anesthetic effects of the dosing schedules were similar; and (3) tiletamine-zolazepam and butorphanol result in decreased CO and MABP with a concomitant increase in SVR, and mild respiratory acidosis. 相似文献
119.
Detecting benzimidazole resistance with faecal egg count reduction tests and in vitro assays 总被引:2,自引:0,他引:2
Composite strains of Trichostrongylus colubriformis and Ostertagia spp consisting of 0, 1, 10, 25, 50, 75, 90, and 100% of known resistant strains were prepared and tested for benzimidazole resistance using faecal egg count reduction tests, in vitro egg hatch assays and tubulin binding assays. All tests detected resistance where the proportion of the resistant strain in the composite was 50% or more, whereas none of the tests unequivocally detected resistance below 25%. Egg count reduction tests were no less sensitive than the in vitro tests in detecting low levels of resistance but the egg hatch and tubulin binding assays provided a better quantitative estimate of moderate to high levels of resistance. Faecal egg count reduction therefore, provides a suitable means of detecting resistance in the field but tests, more sensitive to low levels of resistance are required. Results indicate that the use of post-treatment counts alone provides an adequate indication of anthelmintic efficiency. 相似文献
120.
A. D.J. WATSON D. R. EMSLIE I. C. A. MARTIN J. R. EGERTON 《Journal of veterinary pharmacology and therapeutics》1986,9(2):140-149
Six penicillin preparations were administered to six dogs of various types, both when the dogs were fasted and when fed a standard meal immediately before dosing. The preparations used were: amoxycillin tablets and drops, ampicillin tablets, penicillin V tablets, phenethicillin tablets and cloxacillin capsules. A Latin square design was employed with ampicillin and the two amoxycillin preparations, while three separate cross-over studies were done with penicillin V, phenethicillin and cloxacillin. Dose rates used were 50 mg/kg for cloxacillin, and 10 mg/kg for the others. A microbiological method was used to assay penicillin in blood samples taken at intervals after dosing. Values for peak plasma drug concentration (Cmax), the time at which it occurred (Tmax), and area under the curve (AUC) were obtained for each curve of drug concentration plotted against time. In fasted dogs, ampicillin showed poorer systemic availability than did amoxycillin, with Cmax and AUC values of less than half those of amoxycillin. The solid and liquid preparations of amoxycillin had similar bioavailability. Ingesta adversely affected the systemic availability of antibiotic from all preparations tested. With ampicillin and both amoxycillin preparations, there were reduced Cmax and AUC and prolonged Tmax, indicating slowed and diminished absorption. Feeding did not alter Tmax with the other drugs, but reduced the Cmax of penicillin V, phenethicillin and cloxacillin and the AUC of cloxacillin. It is suggested that, if minimal impairment of bioavailability by ingesta is desired, then the penicillins commonly administered by mouth (amoxycillin, ampicillin, penicillin V, phenethicillin, cloxacillin) should be given to dogs that are fasting. 相似文献