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The clinical and pathological features of extrahepatic cholestasis in 19 dogs are presented. The condition was most often caused by partial or complete occlusion of the choledochal duct due to neoplastic diseases (12 cases), inflammatory processes (3 cases), or eventration and incarceration of the liver (1 case). In only three cases was the condition due to intraluminal obstruction of the choledochal duct. The anamnestic, laboratory and pathological parameters of these 19 dogs were compared with the findings in 21 dogs with intrahepatic cholestasis. Statistical analysis of these parameters indicated that the presence of acholic faeces, the degree of icterus and the level of plasma gamma GT where the only parameters of value in the clinical differentiation of extrahepatic from intrahepatic cholestasis. Histological examination of liver biopsies is a simple aid to a confident in vivo diagnosis of extrahepatic cholestasis.  相似文献   
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The effects of fine suture materials on corneal wound healing in the dog were studied. In 20 dogs, standardized perforating perilimbal clear corneal wounds were made and closed with either monofilament Polyglactin 910 or nylon. Five dogs each were euthanized 8,12,16, and 21 days postoperatively. Results of gross, biomicroscopic, and histologic examinations at 8,12,16, and 21 days showed nylon and Polyglactin 910 to cause similar inflammatory responses. Epithelialization and suppuration around the suture tracts were observed more frequently when Polyglactin 910 was used. Both materials were associated with a foreign body (granulomatous) response. There was no loss of wound integrity with either material. Strengths of the incised corneal tissues with and without the sutures intact were determined. At day 16 postsurgery, there was a statistically significant difference in tissue strengths between cases in which sutures were and were not intact. This difference was not apparent at 21 days postsurgery, which suggested that the suture dependent phase ends between the 16th and 21st postsurgical days. In addition, at day 16 there was no statistical difference between the tissue strength of wounds sutured with nylon or Polyglactin 910. Corneal suture materials studied should remain in place for at least 16 days, and absorbable material is only appropriate if it retains tensile strength for 16 days.  相似文献   
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Results of abdominal survey radiography and x-ray computed tomography (CT) were compared in 13 dogs with hyperadrenocorticism histologically attributed to adrenocortical tumors. X-ray computed tomography enabled accurate localization of the tumor in all 13 dogs. Apart from 2 poorly demarcated irregular-shaped and mineralized carcinomas, there were no differences between adenoma (n = 3) and carcinoma (n = 10) on CT images. In 1 dog, invasion of the caudal vena cava by the tumor was suggested on CT images and was confirmed during surgery. Suspicion of adhesions between tumors of the right adrenal gland and the caudal vena cava on the basis of CT images was confirmed during surgery in only 2 of 6 dogs. Survey radiography allowed accurate localization of the tumor in 7 dogs (4 on the right side and 3 on the left). In 6 of these dogs, the tumor was visible as a well-demarcated soft tissue mass and, in the other dog, as a poorly demarcated mineralized mass. The smallest tumor visualized on survey radiographs had a diameter of 20 mm on CT images. Six tumors with diameter less than or equal to 20 mm were not visualized on survey radiographs. In 1 of these dogs, a mineralized nodule was found in the left adrenal region, without evidence of a mass. In a considerable number of cases, survey radiography can provide presurgical localization of adrenocortical tumors in dogs with hyperadrenocorticism; CT is redundant in these instances. In the absence of positive radiographic findings, CT is valuable for localization of adrenocortical tumors.  相似文献   
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The aim of our retrospective study was to produce and analyse epidemiological data on gastrointestinal (GI) disorders of Austrian leisure horses. Case records of horses referred to the Equine Clinic of the Veterinary University of Vienna were collected from an electronic hospital information system using its search options. All cases reported to have suffered a GI disorder between March 2003 and February 2015 were selected. In this period of 4314 days, data of 1833 GI cases, mostly accompanied by colic signs, were analysed. The vast majority of our GI cases appeared in the abdominal parts of the GI tract 96% (1760/1833) while just 1.3% (24/1833) could be definitively attributed to oesophageal disorders, whereas in 2.7% (49/1833) of the cases a definitive diagnosis could not be made. The highest prevalence of GI disorders was seen in July and October/November. A breakdown of figures for cases clustered under the colic syndrome showed that colon impactions in left ventral large and/or pelvic flexure (35%) were the major problem followed by gastric disorders (18%), spasmodic colic (9%), enteritis (7%), caecal tympany (6%); caecal impaction (4%), colitis (3%), abnormal anatomical positions of large colon including complete and partial strangulation/volvulus, nephrosplenic entrapment of the left ventral and dorsal colon and right dorsal displacement of the large colon (3%) and small intestinal volvulus (2.7%). In 12% of the cases, the cause of the abdominal discomfort was likely idiopathic paralytic ileus. The searching tool of the electronic patient data also brought up cases with malabsorbtion/IBD syndrome and GI ruptures, both these contributed less than 1% of the referred GI cases. Results suggested that the causes of colic are diverse, but the major reasons for referred cases of colic in the east Austrian horse population are large colon impaction or displacements. Seasonal distribution and specific causes of gastrointestinal disorders should be considered essential components of the initial clinical assessment of horses presenting with colic.  相似文献   
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A 2-month-old Warmblood colt presented with recurrent colic and regurgitation. Gastroscopy, performed on several occasions, and barium-contrast radiography revealed severe squamous gastric ulceration and stenosis at the level of the margo plicatus. Treatment with omeprazole reduced the extent and severity of the gastric ulcers but did not affect the stenosis. The foal was euthanised because of a poor prognosis, and post-mortem examination confirmed the clinical diagnosis. Severe squamous gastric ulceration, granulation tissue formation and cicatrisation of deep gastric lesions were considered to have caused the stenosis. Gastroduodenal outflow obstruction is a recognised disorder in foals, but stenosis at the level of the margo plicatus has not been reported in foals or adult horses. To the authors' knowledge, this is the first case of severe squamous gastric ulceration, complicated by stenosis at the level of the margo plicatus, in a foal. Although rare, gastric stenosis should be considered in foals suffering recurrent colic and regurgitation.  相似文献   
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The previous paper in this series demonstrates the use of a nuclear magnetic resonance (NMR) micro-imaging system to observe the movement of liquid water through small specimens (11 × 16 mm2 cross-section) of oriented strandboard (OSB) and solid wood. In the present paper, a NMR body scanner is utilized to obtain images of moisture penetration into ASTM D 1037–99 standard sized (152 × 152 mm2) thickness swelling specimens at different intervals during water soaking. As with the micro-imaging study, silicone was applied to the surfaces and edges of some of the specimens in order to observe the directional characteristics of moisture movement through OSB. Specimens with commercially applied edge sealant were also included in the study in order to observe the effectiveness of the sealant of reducing moisture penetration and thickness swelling. The presence of voids and areas of low density were shown to contribute significantly to moisture penetration into the specimens.  相似文献   
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