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排序方式: 共有502条查询结果,搜索用时 15 毫秒
81.
An outbreak of acute, fatal, hemorrhagic pneumonia was observed in more than 1,000 mixed breed dogs in a single animal shelter. The Department of Anatomic Pathology at the University of California at Davis School of Veterinary Medicine performed necropsies on dogs that were found moribund in acute respiratory distress or found dead with evidence of nasal bleeding. All dogs had hemothorax and an acute, fibrinosuppurative pneumonia. Large numbers of gram-positive cocci were observed within the lungs of all dogs and within septic thromboemboli of remote organs in about 50% of cases. Bacterial cultures from the dogs and their environment revealed widespread beta-hemolytic Streptococus equi subspecies zooepidemicus (Lancefield Group C). Extensive diagnostic testing failed to reveal the consistent presence of copathogens in individual cases. The clinical, epidemiologic, molecular biologic, and pathologic data indicate that a single clone of S. zooepidemicus was the cause of an acutely fatal respiratory infection in these dogs.  相似文献   
82.
Objective – To describe general anesthesia and successful resuscitation of a dog developing asystole and apnea during extradural injection of local anesthetic and an opioid. Case Summary – A Beagle with a ruptured cranial cruciate was premedicated with acepromazine and methadone. Anesthesia was induced with propofol and, after endotracheal intubation, maintained using isoflurane in oxygen. During extradural injection of a mixture of lidocaine, bupivacaine, and morphine the dog developed apnea and asystole. Cardiopulmonary cerebral resuscitation was started promptly and the dog was successfully resuscitated. New Information Provided – Asystole and apnea are possible serious side effects of extradural anesthesia in dogs. With adequate monitoring and early detection successful resuscitation is possible.  相似文献   
83.
84.
Computed tomography (CT) was performed on 12 Finnhorse cadaver forefeet with known radiographic changes in the navicular bone (poor corticomedullary junction, irregular appearance of the flexor central eminence, uneven or unequal thickness of the flexor cortex, and/or irregular outline of the proximal or distal flexor margin). The purpose was to confirm the radiographic findings and to investigate if further information of the flexor aspect of the bone could be gained with CT. In CT, the midsagittal outline as well as the internal structure of the bones varied greatly. Different combinations of trabecular and compact bone were seen within the flexor central eminence. Lucencies within the compact bone were commonly present in the proximal half of the eminence, but in five bones lucencies were also identified in the distal half. Due to partial overlapping of the bone and varying bony composition of the eminence, accurate radiographic evaluation of the shape and internal structure of the flexor central eminence was often found to be difficult. The flexor cortex usually appeared to be thinner in CT than in conventional radiographs. Medullary sclerosis and poor flexor corticomedullary junction were commonly overinterpreted radiographically. New bone formation on the proximal flexor margin of the navicular bone was generally visualized in radiographs, but CT allowed also the evaluation of the internal structure of the bone. In one navicular bone, an avulsion fragment on the distal flexor margin was seen in CT images; radiographically this fragment could not be visualized. It was concluded that the flexor aspect of the navicular bone may be difficult to assess reliably with conventional radiography.  相似文献   
85.
OBJECTIVE: To evaluate the effect of arthroscopic subchondral bone microfracture on healing of large chondral defects in horses. STUDY DESIGN: Short- (4 months) and long-term (12 months) in vivo experimental chondral defect model. ANIMALS: 10 horses, aged 2 to 5 years. METHODS: Each horse had a 1 cm2 full-thickness chondral defect created in both radial carpal bones and both medial femoral condyles. One carpus and one femoral condyle of each horse had the subchondral bone plate under the defect perforated using an orthopedic awl. All horses were exercised, five horses were evaluated after 4 months and five horses after 12 months. Gross, histologic, and histomorphometric examination of defect sites and repair tissues was performed, as was collagen typing of the repair tissue. RESULTS: On gross observation a greater volume of repair tissue filled treated defects (74%) compared with control defects (45%). Histomorphometry confirmed more repair tissue filling treated defects, but no difference in the relative amounts of different tissue types was observed. There was an increased percentage of type II collagen in treated defects compared with control defects and evidence of earlier bone remodeling as documented by changes in porosity. CONCLUSIONS: In full-thickness chondral defects in exercised horses, treatment with subchondral bone microfracture increased the tissue volume in the defects and the percentage of type II collagen in the tissue filling the defects when compared to nontreated defects. CLINICAL RELEVANCE: No negative effects of the microfracture technique were observed and some of the beneficial effects are the basis for recommending its use in patients cases with exposed subchondral bone.  相似文献   
86.
ObjectivesTo evaluate whether a period of hyperoxia or after a period of hypoxia produced changes attributable to reactive oxygen species in anaesthetized horses.Study designProspective randomized experimental study.AnimalsSix healthy (ASA I) geldings, aged 4.5–9.5 years and weighing 510–640 kg?1.MethodsAfter 30 minutes breathing air as carrier gas for isoflurane, horses were assigned randomly to breathe air as carrier gas (CG0.21) or oxygen as carrier gas (CG1.00) for a further 90 minutes. After an interval of 1 month each horse was re-anaesthetized with the other carrier gas for the 90 minute test period. Ventilation was controlled throughout anaesthesia. Arterial blood was sampled to measure gas tensions, lactate, cholesterol, vitamin E, 4-hydroxy-alkenals, 8-epi-PGF, half haemolysis time, half erythrolysis time, and erythrocyte membrane fluidity. Muscle blood flow and oxygenation were evaluated by near infrared spectroscopy and coloured Doppler.ResultsAfter the first 30 minutes horses were hypoxemic. Subsequently the CG1.00 group became hyperoxaemic (PaO2~240 mmHg) whereas the CG0.21 group remained hypoxaemic (PaO2~60 mmHg) and had increased lactate concentration. No significant changes in vitamin E, 4-hydroxy-alkenals, or 8-epi-PGF concentrations were detected. During the 90 minute test period the CG0.21 group had increased resistance to free-radical-mediated lysis in erythrocytes, whereas the CG1.00 group had slightly decreased resistance of whole blood to haemolysis. CG0.21 induced a progressive muscle deoxygenation whereas CG1.00 induced an increase in muscle oxygen saturation followed by progressive deoxygenation towards baseline.Conclusions and clinical relevanceDuring isoflurane anaesthesia in horses, the hyperoxia induced by changing from air to oxygen induced minimal damage from reactive oxygen species. Using air as the carrier gas decreased skeletal muscle oxygenation compared with using oxygen.  相似文献   
87.
A 5-year-old English Bulldog was presented for acute onset of syncope and fatigue caused by sustained ventricular tachycardia with left bundle block morphology and inferior axis. This arrhythmia had the electrocardiographic features of a ventricular tachycardia arising from the right ventricular outflow tract (RVOT), as described in an experimental canine model and in people. Since a RVOT aneurysm was identified by echocardiography, a segmental form of arrhythmogenic right ventricular cardiomyopathy (ARVC) was suspected. Gross examination of the heart confirmed the bulging of the RVOT and histological examination of the ventricular myocardium revealed segmental involvement of the RVOT with transmural fibro-fatty degeneration. To the authors' knowledge, this is the first reported case of AVRC in an English Bulldog and the first example of segmental AVRC described in the dog.  相似文献   
88.
This study was aimed at assessing the changes in sperm motion patterns and the percentage of acrosome reaction (AR) in domestic cat semen after treatment with either ionomycin or progesterone (P4). Ten ejaculates were collected from five tomcats using an artificial vagina, and were diluted, centrifuged and resuspended in a capacitation medium. Samples were evaluated and divided into seven equal aliquots and, after 2 h at 25°C, were incubated for 30 min at 38°C in 5% CO2 and then analyzed. Computer-assisted sperm analysis and a combination of three fluorescent probes were used to assess sperm plasma, acrosomal membrane integrity and mitochondrial transmembrane potential. Thirty minutes after the start of incubation, P4 was added (10 μg/ml) to the P1 group. Groups P2 and P3 were supplemented with P4 (10 and 20 μg/ml, respectively) only after 2 h of incubation, and groups I1 and I2 were supplemented with ionomycin (4 and 8 μ m , respectively) 2 h after incubation. Group E was supplemented with ethanol (0.6%) at 2 h after incubation and group C received no supplementation. Ionomycin and P4 treatments led to a hyperactivation-like sperm motion and an increase (p < 0.05) in the percentage of AR. Although a higher (p < 0.05) percentage of AR was obtained in group I2 when compared with all P4 groups, a decrease (p < 0.05) in total and progressive motility was observed in I2 group. As I1 group was similar to I2 to induce AR without diminishing sperm motility, we can conclude that ionomycin at 4 μ m seems to be more suitable to trigger AR in domestic cat sperm.  相似文献   
89.
The aim of this study was to investigate the impact of a 24-h cooling period prior to freezing on domestic cat epididymal sperm viability. Fifteen tomcats were submitted to routine orchiectomy and sperm samples were retrieved from both epididymides in a Tris–glucose–20% egg yolk extender. For each tomcat, the diluted sperm was split into two equal volumes and cooled to 5°C at a rate of 0.5°C/min; one sample for 60 min (control) and the other for 24 h (cooled). After the cooling period, samples from both groups were frozen using an identical freezing protocol. Sperm samples were evaluated in three different periods: immediately after harvesting, after cooling at 5°C for 24 h (cooled group) and after freezing–thawing of control and cooled groups. Evaluations consisted of sperm motility and progressive status, sperm morphology and plasma membrane integrity (PMI) using two fluorescent probes. After cooling for 24 h, a decrease (p < 0.05) in sperm motility, progressive status and PMI was observed when compared to sperm samples immediately after collection. Comparing the results obtained after thawing, no difference (p < 0.05) was found regarding sperm motility, progressive status, PMI and sperm morphology between control and cooled groups. The results from the present study show that cooling cat epididymal spermatozoa at 5°C for 24 h prior to freezing does not lead to major damage of spermatozoa impairing the freeze–thaw process.  相似文献   
90.
The purpose of this study was to determine whether or not embryos derived from in vitro fertilization of oocytes from persistently infected (PI) cattle would contain infectious virus. Three in vitro embryo production treatment groups were assessed: 1) oocytes and uterine tubal cells (UTC) free of bovine viral diarrhoea virus (BVDV) (negative control), 2) oocytes free of BVDV fertilized and cultured in media containing UTC obtained from PI heifers, and 3) oocytes from PI heifers fertilized and cultured in media containing UTC free of BVDV. The developmental media, UTC and embryos (individual or groups of five) were assayed for virus. Virus was not isolated from any samples in treatment group 1. As shown in previous studies, a proportion of embryo samples were positive for BVDV in treatment group 2. In treatment group 3, the virus associated with the oocytes contaminated the developmental media and infected susceptible co-culture cells used during fertilization and culture. In addition, 65% (11/17) of the degenerated ova from treatment group 3 had infectious virus associated with them. While none of the ova developed into transferable embryos, the study did confirm that use of oocytes from PI cows could lead to amplification of BVDV and cross contamination during in vitro embryo production.  相似文献   
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