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排序方式: 共有467条查询结果,搜索用时 31 毫秒
461.
Tobias Schwarz MA Dr. med. vet. Martin Sullivan BVMS PhD Klaus HartungProf. Dr. med. vet. 《Veterinary radiology & ultrasound》2000,41(3):226-230
The sensitivity of conventional radiography for lesions of the cribriform plate, naso-orbital wall, lateral nasal wall and hard palate was investigated in 13 canine cadaver heads by creating measured defects in these structures. The location of the perforations were marked with a thin copper wire and the radiographic appearance of the defects was evaluated retrospectively by a single reviewer. Despite demarcation cribriform plate destruction of 2 mm could not be detected. Defects of 3 mm were detected in only 2 heads, 4 mm defects in 1 further head, an oblong 4 x 10 mm defect in 7 heads and in the remaining 3 heads only a 10 x 10 mm defect became visible as such. The naso-orbital wall had to be destroyed in its whole vertical length for detection of a defect in ventrodorsal or dorsoventral views. Therefore conventional radiography is of low diagnostic value for these lesions. Defects of 2 mm in the lateral nasal wall and the hard palate could be detected confidently in all heads indicating high sensitivity of conventional radiography. Soft tissue opacification did not alter the detectability of any nasal border structure lesion. 相似文献
462.
Tobias Schwarz MA Dr. Med. Vet. Federica Morandi DVM Giacomo Gnudi Dr. Med. Vet. Erik Wisner DVM Calum Paterson MSc Martin Sullivan BVMS PhD Pamela Johnston BVM&S PhD 《Veterinary radiology & ultrasound》2000,41(4):335-339
The radiographic appearance of nodular fat necrosis is described in ten cats and one dog. The most common radiographic sign was the presence of a focal mineralized circular to oval soft tissue mass in the abdominal fat as present in 9 cats. These masses had a distinct eggshell-like rim encapsulating the lesion. In one cat and one dog multiple masses were present, without radiographic signs of mineralization. Abdominal ultrasound was performed in three cats and one dog, findings included the presence of hyperechoic masses with associated acoustic shadowing, some with a hypoechoic centre. Almost all animals were old and obese. In three cats and one dog, changes were confirmed with biopsy or post mortem examination. Lesions having the appearance of those in this paper are most likely incidental findings and should not be confused with abdominal masses of neoplastic origin. Ultrasound can be helpful in identifying such lesions. 相似文献
463.
Lindgren P. M. F.; Sullivan T. P.; Sullivan D. S.; Brockley R. P.; Winter R. 《Forestry》2007,80(5):587-611
This study was designed to test the hypothesis that large-scalepre-commercial thinning (PCT) to various stand densities, atages 12–14 years, combined with repeated fertilization,would, over a 10-year treatment period, enhance productivityof lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifoliaEngelm.) crop trees. Study areas were located near Summerland,Kelowna and Williams Lake in south-central British Columbia,Canada. Each study area had nine treatments: four pairs of standsthinned to densities of 250 (very low), 500 (low), 1000 (medium)and 2000 (high) stems ha–1, with one stand of each pairfertilized five times at 2-year intervals, and an unthinnedstand. The very low, low- and medium-density stands were alsopruned to a 3-m lift 5 years after thinning. At the tree level,fertilization treatments significantly increased diameter atbreast height (DBH), basal area (BA) and volume growth and heavyPCT significantly increased DBH and BA growth. Pruning may mitigatesome of the negative stem form and wood quality attributes associatedwith fast-growing trees without adversely affecting stem growth.At the stand level, PCT to very low and low densities significantlydecreased the volume growth compared with high-density stands.The potential beneficial impacts that PCT and repeated fertilizationtreatments have for mitigating timber supply shortfalls, aswell as potentially minimizing crop tree losses due to mountainpine beetle (Dendroctonus ponderosae Hopk.), are also discussed. 相似文献
464.
C. Sullivan 《Land Degradation \u0026amp; Development》2004,15(1):98-98
465.
Kristen J. Reynolds Ron Johnson Robert M. Friendship Jennifer Brown Saad Enouri Ronette Gehring Terri L. OSullivan 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(11):1211
In Canada, piglets receive analgesia to control pain after surgical castration. There is interest in examining the potential to mix non-steroidal anti-inflammatory drugs with iron dextran prior to injection to minimize piglet handling and labor. The objective of this study was to compare pharmacokinetics and the relative bioavailability of ketoprofen given alone (3.0 mg/kg IM) versus the same dose of ketoprofen mixed with iron dextran (52.8 mg/kg IM) (ketoprofen + iron dextran) before injection in piglets. Piglets 8 to 11 d old were allocated into 2 treatment groups (n = 8/group). Plasma drug concentrations were measured using mass spectrometry at 13 time points after injection. No significant differences were detected between the 2 groups when examining pharmacokinetic parameters (e.g., Cmax, Tmax, AUC) or relative bioavailability for either S- or R-ketoprofen enantiomers (P > 0.05). However, pain control efficacy and food safety studies of these formulations are required to further examine this practice. 相似文献
466.
Carly V. Sullivan Joshua Zuckerman Catherine Popovitch 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(11):1219
The surgical approach for excision of caudal thigh intermuscular lipomas (IML) in dogs is described with relevant anatomy and short-term outcomes reported. Medical records were reviewed to identify dogs that underwent IML excision between 2015 to 2019. Signalment, location of the lipoma, pre-operative diagnostic tests, histopathology results, use of a closed-suction drain, and follow-up information including drain and suture removal were recorded. Mean age of patients in this study was 8.7 years. Multiple breeds were affected and there was no predilection for either left or right hind limb. Pre-operative diagnostic tests included fine-needle aspirate, radiography, peripheral ultrasonography, and/or computed tomography scan. In 45% (5/11) of the cases, a closed suction drain was placed. All masses removed were deemed grossly consistent with a lipoma by the attending clinician and 5 were confirmed by histopathology. No complications were noted in any case. Removal of caudal thigh IML requires careful identification of and dissection around the sciatic nerve, which is easily achieved with appropriate knowledge of the relevant anatomy and surgical approach. 相似文献
467.
C. Lin M. Rosicky D. McConchie L. A. Sullivan G. Lancaster 《Land Degradation \u0026amp; Development》2001,12(4):293-303
Scalded lands are common in acid sulphate soil areas on the New South Wales coast, Australia. In this work, chemical characteristics of the scalded acid sulphate soils at nine sites along this coast were investigated. The investigated acid sulphate scalds are characterized by an extremely acidified topsoil layer (0–0.6 m) although they derive from the sediments of varying salinity and the metal sulphides contained in the soils have experienced different degrees of oxidation. Almost all of the investigated scalds occur in the areas that have a lower surface elevation than the surrounding areas. These hollows may act as sinks for acid sulphate materials and salts that are transported from the surrounding areas and the shallower watertables in such locations may enhance upward transport of acid and salt materials from the underlying oxidized sulphidic sediments. In general, the scalded acid sulphate soils have less organic matter and soluble phosphorus, and a greater salinity, soluble acidity, soluble Al, Mn and Zn concentrations, compared to the adjacent non‐scalded acid sulphate soils. These are most likely soil constraints for revegetation of the scalded lands and treatment will need to involve acid neutralization (e.g. application of lime) and addition of P fertilizers to reduce the soluble acidity, immobilize soluble Al, Mn and Zn, and increase P availability. The evidence also shows that the higher soluble Al concentration in the scalded soils, relative to the non‐scalded soils, is related to their lower organic matter content. Hence, rehabilitation of these scalded lands should involve the addition of organic matter to reduce soluble Al concentrations; it may also help reduce Mn and Zn toxicity, and salinity. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献