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排序方式: 共有613条查询结果,搜索用时 109 毫秒
191.
192.
ROBERT T. PERNELL DVM MS Diplomate ACVS JAMES L. MILTON DVM MS Diplomate ACVS ROBERT S. GROSS PhD RONALD D. MONTGOMERY DVM MS Diplomate ACVS JAMES G.W. WENZEL DVM PhD Diplomate ACT CARL G. SAVORY MD FACS HAROLD M. ABERMAN DVM MSE 《Veterinary surgery : VS》1995,24(4):337-346
Cementless femoral stems were placed into 12 normal greyhound femora. The implanted femora were divided into three groups by stem orientation and implant size and loaded in axial compression at a rate of 25 newtons (N) per second until failure. Rosette strain gauges were used to measure femoral principal strains at 500 N, 1,000 N, 1,500 N, and at maximum load. During maximum load, varus orientation of the femoral stem had significantly higher tensile hoop strains in the proximomedial cortex, whereas neutral orientation had higher tensile hoop strains along the cranial cortex. Femoral fractures occurred in these areas of peak tensile strain. There was no difference in maximum load between groups, therefore varus orientation did not predispose to fracture. Maximizing canal fill and implant fit increased implant stability. 相似文献
193.
194.
Philip D. Koblik DVM MA Chi-K Yen MD William J. Hornof DVM MS Pamela Whiting DVM Paul Fisher BS 《Veterinary radiology & ultrasound》1989,30(2):67-73
Transcolonic 123 I-Iodoamphetamine is rapidly absorbed across the colonic mucosa and binds to amine receptors in the liver and lungs. During the first ten minutes following colonic administration, a simple ratio of lung counts to lung counts plus liver counts provides an accurate estimate of the fraction of portal blood that bypasses hepatic sinusoids in dogs with portosystemic shunts. Studies were performed on 24 dogs with suspect portosystemic shunt. Shunt fraction values for 18 dogs with surgically confirmed portosystemic shunt were obviously higher than published values for normal dogs, and also significantly higher than values for the other six dogs, later confirmed to lack shunts. Postoperative studies were repeated on ten dogs with single shunt vessels 1–2 days after shunt closure. Total shunt ligation resulted in normal postoperative shunt fraction, whereas partial shunt ligation resulted in persistant elevation of shunt fraction. Transcolonic iodoamphetamine scintigraphy is noninvasive, easy to perform, and provides an accurate method to diagnose dogs with portosystemic shunt. 相似文献
195.
196.
P.J. Burns PhD M.J. Jawad MS J.M. Weld MVB MRCVS W.C. Kaufman DVM D.M. Witherspoon DVM PhD E.A. Wilson MD R.H. Douglas PhD 《Journal of Equine Veterinary Science》1984,4(5):202-208
Testicular diameters and monthly blood samples were obtained from 83 stallions aged 4 to 22 years that were maintained on Central Kentucky Thoroughbred stud farms. The effects of age, season, and exposure to increased photoperiod (16 hours light/day, December 15 to April 1) on testicular diameters and plasma concentrations of FSH, LH and testosterone were studied.The results indicated that Thoroughbred stallions show distinct seasonal and age related changes in most of the reproductive parameters studied and that exposure of such stallions to increased photoperiod produced significant alterations in these changes. Although lighting stimulated testicular growth and testosterone secretion early in the breeding season such changes were short lived. Lighted stallions appeared to become refractory to the lighting program since both testicular size and plasma testosterone concentrations were significantly reduced by June. 相似文献
197.
Earl F. Calfee III DVM Otto I. Lanz DVM Diplomate ACVS Daniel A. Degner DVM Diplomate ACVS Steven L. Peterson DVM MS MD Diplomate ACVS Robert B. Duncan DVM PhD Diplomate ACVP Richard V. Broadstone DVM PhD Diplomate ACVA Robert A. Martin DVM Diplomate ACVS ABVP Brenda Austin BS 《Veterinary surgery : VS》2002,31(1):32-43
OBJECTIVE: To assess donor-site morbidity and survival of the rectus abdominis muscle with an overlying skin graft after free tissue transfer to a medial femorotibial defect in dogs. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Phase 1: 6 canine cadavers; phase 2: 7 adult mixed-breed dogs. METHODS: Phase 1: The rectus abdominis muscle was removed from canine cadavers, muscular and vascular dimensions were recorded, and angiography was performed. Phase 2: Muscular transfer was performed through anastomosis of the caudal epigastric artery and vein to the saphenous artery and medial saphenous vein. Transferred tissues were evaluated on postoperative days 3, 6, 10, and 13. Animals were examined daily until euthanasia between postoperative days 31 and 42. Postmortem angiograms were performed and tissues collected for histopathologic evaluation. RESULTS: Phase 1: Appropriate vascular dimensions for microvascular anastomosis were confirmed and surgical technique perfected. Phase 2: Muscular excision produced minimal donor-site morbidity. All muscles survived after microvascular transfer and angiography confirmed vascular patency. All of the skin grafts survived, with one graft undergoing partial necrosis. CONCLUSIONS: The rectus abdominis muscle can be successfully transferred to a medial femorotibial defect and can serve as a bed for acute skin grafting. No significant donor-site morbidity is associated with its removal. CLINICAL RELEVANCE: Microvascular free tissue transfer of the canine rectus abdominis muscle has not been previously described. This technique provides a new alternative for repair of appropriate wounds. Additional studies are needed to define its utility in clinical patients. 相似文献
198.
Dongwoo Chang DVM MS Bongkyeong Kim DVM MS Youngmin Yun DVM PHD Yongmin Hur MD Youngwon Lee DVM PHD Mincheol Choi DVM PHD Junghee Yoon DVM PHD Jekyung Seong DVM PHD 《Veterinary radiology & ultrasound》2002,43(1):37-42
The role of superparamagnetic iron oxide as a tissue-specific contrast medium has been established in humans, especially for hepatic imaging. Superparamagnetic iron oxide particles exhibit a tissue-specific biodistribution to the reticuloendothelial system, where they predominantly shorten transverse T2 relaxation time. Most hepatic tumors lack Kupffer cells; therefore, the T2 of tumors remains virtually unchanged after administration of superparamagnetic iron oxide. The resulting loss of signal intensity from the liver, with unchanged tumor signal intensity, increases lesion-to-liver contrast. In this study, MR images were acquired with fast gradient echo recalled at steady state (FGRE) in five Beagle dogs before and after injection of superparamagnetic iron oxide. The effect of superparamagnetic iron oxide on signal intensity of the liver with time was assessed. A signal intensity decrease of 65.7+/-10.0% was detected at 20 minutes, and it continued to decrease until the last time point of MR scanning (200 minutes). The liver intensity of all dogs dropped to half its value after 20 minutes. The effect of motion was minimized by breath holding. Superparamagnetic iron oxide did not have any adverse effects on the dogs. 相似文献
199.
Eduardo A. Guarnera MD Elisa M. Zanzottera MVD Hector Pereyra MD Anibal J. Franco MVD 《Veterinary radiology & ultrasound》2001,42(4):352-354
The sanitary and economic impact of cystic echinococcosis is serious in those countries where it becomes endemic. Ultrasonography is one technique that may be used to diagnose this disease in endemic areas. In parasitized sheep, hydatid cysts appear sonographically as a round hypoechoic structure. Twenty two sheep destined for slaughter were studied sonographically and imaging findings compared to post-mortem findings. Three sheep with hydatid cysts were identified. Eighty additional sheep not destined for slaughter were also studied. Echinococcus granulosus cysts were detected in three animals. Forty sheep from a non-endemic area had no hepatic cysts. The in vivo sonographic study of sheep provides a useful screening tool for echinococcosis. 相似文献
200.
Andrew E. Kyles BVMS PhD Diplomate ACVS Diplomate ECVS Clare R. Gregory DVM Diplomate ACVS Stephen M. Griffey DVM PhD Jose Galvez MD Rajen Ramsamooj MD Randall E. Morris MD 《Veterinary surgery : VS》2002,31(1):49-56
OBJECTIVES: To describe the clinical signs and histopathologic features of renal allograft rejection in cats, and to provide a historical, untreated control group for use in future studies of feline renal allograft rejection. ANIMALS: Fourteen adult research cats. METHODS: Renal transplantation and bilateral nephrectomy were performed in pairs of immunogenically mismatched cats. A physical examination was performed, and packed cell volume, total protein, and plasma creatinine concentrations were measured each day after surgery. The cats were euthanatized when plasma creatinine concentration exceeded 7 mg/dL or when weight loss exceeded 20%. Renal histopathology was scored according to the Banff 97 criteria by 3 pathologists. RESULTS: Nine cats completed the study. Plasma creatinine exceeded 7 mg/dL in 5 cats, weight loss exceeded 20% in 3 cats, and 1 cat was found dead. Clinical signs in cats with rejection were nonspecific or absent. Rectal temperature decreased by 0.8 +/- 0.5 degrees C in the 24 hours before euthanasia. The pathologists agreed on the allograft histopathologic category in 6 of 9 cats. The histologic consensus was acute/active rejection in 8 cats and normal in 1 cat. Median survival time of the 8 cats with histologically confirmed allograft rejection was 23 days (range, 8-34 days). CONCLUSIONS AND CLINICAL RELEVANCE: Renal allograft rejection is associated with minimal clinical signs. Therefore, plasma creatinine concentration should be measured routinely in patients with a functioning allograft. An increase in plasma creatinine concentration is highly suspicious for allograft rejection, although a biopsy of the renal allograft is needed for definitive diagnosis. 相似文献