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111.
An 8-month-old German Shepherd dog was presented for investigation of pelvic limb gait abnormality. Neurolocalization indicated a T3-L3 spinal cord lesion. The myelographic appearance was of an intramedullary lesion at T9/10, but upon subsequent magnetic resonance imaging it was determined that the mass was extramedullary. A diagnosis of nephroblastoma was made on histological examination. The imaging features of this rare tumor and the differentiation of intradural-extramedullary and intramedullary masses are discussed.  相似文献   
112.
MAGNETIC RESONANCE IMAGING OF THE NORMAL FELINE BRAIN   总被引:2,自引:1,他引:1  
The Purpose of this study was to produce an atlas of magnetic resonance images (MRI) of the feline brain and associated structures. The head of nine clinically normal cats was imaged in 2 or 3 anatomic planes and 3 sets of technical parameters resulting in T1, T2, and proton-weighted density images. Images were compared with anatomic texts, with preserved and sectioned feline cadaver heads, with preserved and sectioned feline brains, and with intact, sectioned, and disarticulated feline skulls for aid in identification of structures. Anatomic and neuroanatomic structures are identified on selected images in different planes as reference for MR morphology of the normal feline brain and related structures.  相似文献   
113.
Escherichia coli is one of the major pathogens in humans and animals causing localized and systemic infections, which often lead to acute inflammation, watery diarrhea, and hemorrhagic colitis. Bacterial lipopolysaccharide (LPS) and Shiga exotoxins (Stx) are mostly responsible for such clinical signs. Therefore, highly effective treatment of E. coli infections should include both eradication of bacteria and neutralization of their toxins. Here, for the first time, we compared the in vitro ability of common antibiotics to decrease LPS‐ and Stx‐mediated cytotoxicity: colistin, amoxicillin (used separately or combined), enrofloxacin, and its metabolite ciprofloxacin. Three experimental scenarios were realized as follows: (a) the direct effect of antibiotics on endotoxin, (b) the effect of antibiotic treatment on LPS‐mediated cytotoxicity in an experiment mimicking “natural infection,” (c) the effect of antibiotics to decrease Stx2e‐mediated cytotoxicity. Two cell lines, A549 and Vero cells, were used to perform cytotoxic assays with the methyl tetrazolium (MTT) and lactate dehydrogenase leakage (LDH) methods, respectively. Colistin and amoxicillin, especially used in combination, were able to attenuate LPS toxic effect, which was reflected by increase in A549 cell viability. In comparison with other antibiotics, the combination of colistin and amoxicillin exhibited the highest boster or additive effect in protecting cells against LPS‐ and Stx2e‐induced toxicity. In summary, in comparison with fluoroquinolones, the combination of colistin and amoxicillin at concentrations similar to those achieved in plasma of treated animals exhibited the highest ability to attenuate LPS‐ and Stx2e‐mediated cytotoxicity.  相似文献   
114.
A case of corneal sequestrum in a 9-year-old Shih Tzu is reported. On the ophthalmic examination a brown-pigmented ulcer with mild edema and corneal vascularization was present. The brownish plaque was facing an inferior palpebral tumor. A superficial keratectomy followed by a grid keratotomy and removal of the palpebral mass were performed. Histological findings revealed an inflammatory cell infiltration underneath the acellular stromal layers. No melanin granules were observed. No vascular infiltration was present within the necrotic stroma. The surgical area healed and no recurrence has been reported by the owners at the time of writing. To the authors' knowledge, this is the first report of a corneal sequestrum in a dog.  相似文献   
115.
116.

Context

Methods quantifying habitat patch importance for maintaining habitat network connectivity have been emphasized in helping to prioritize conservation actions. Functional connectivity is accepted as depending on landscape resistance, and several measures of functional inter-patch distance have been designed. However, how the inter-patch distance, i.e., based on least-cost path or multiple paths, influences the identification of key habitat patches has not been explored.

Objectives

We compared the prioritization of habitat patches according to least-cost distance (LCD) and resistance distance (RD), using common binary and probabilistic connectivity metrics.

Methods

Our comparison was based on a generic functional group of forest mammals with different dispersal distances, and was applied to two landscapes differing in their spatial extent and fragmentation level.

Results

We found that habitat patch prioritization did not depend on distance type when considering the role of patch as contributing to dispersal fluxes. However, the role of patch as a connector facilitating dispersal might be overestimated by LCD-based indices compared with RD for short- and medium-distance dispersal. In particular, when prioritization was based on dispersal probability, the consideration of alternatives routes identified the connectors that probably provided functional connectivity for species in the long term. However, the use of LCD might help identify landscape areas that need critical restoration to improve individual dispersal.

Conclusions

Our results provide new insights about the way that inter-patch distance is viewed changes the evaluation of functional connectivity. Accordingly, prioritization methods should be carefully selected according to assumptions about population functioning and conservation aims.
  相似文献   
117.
118.
A 6-year-old male elk presented in August with a 4-month history of weight loss and a 1-day history of being recumbent and unable to rise. The elk's body condition score was 1.5/5. Hematology and blood chemistry showed an inflammatory leukogram, mild electrolyte abnormalities, and elevated liver enzyme activities. Because of poor prognosis, the owner elected euthanasia. On necropsy, 8 diverticula were in the duodenum distal to the common bile duct, which was dilated and filled with feed material. Many intrahepatic bile ducts were dilated up to 5 cm, were filled with ingesta and gritty material, and had walls thickened up to 1.5 mm. On histologic examination, mural thickening of dilated bile ducts was because of increased fibrous connective tissue with inflammatory cell infiltration and hyperplastic and hypertrophic epithelial lining. Portal tracts diffusely contained hyperplastic bile ducts and had increased amounts of fibrous connective tissue. Abscesses that contained bacteria were scattered throughout the liver. Duodenal diverticula lacked the tunica muscularis, and the muscularis mucosa was hypertrophied. Caudal to some diverticula, the duodenal lumen was narrowed. An additional finding was embolic pneumonia with fungi morphologically and immunohistochemically consistent with Aspergillus spp.  相似文献   
119.
There is scant literature on primary nonhematopoietic malignant liver tumours (PMLT) in cats. In this retrospective study, medical data of 40 cats diagnosed with PMLT were reviewed over a period of 22 years (2000–2021). The most frequent epithelial tumours were hepatocellular (42.5%) and bile duct carcinomas (32.5%), only six (15%) cats had mesenchymal tumours. The median age was 13 years and clinical signs commonly included ano-/hyporexia (62.5%), apathy/lethargy (52.5%), weight loss (42.5%) and vomiting (35%). At initial diagnosis, metastases were confirmed in 1 (2.5%) and suspected in three (7.5%) cats. Massive was the most frequent morphology (75%). Most intrahepatic tumours were left-sided (54.2%) with the left medial lobe being primarily affected (25%). Extrahepatic tumours were rare (5%). In 34 (85%) cats, liver lobectomy was performed (surgery group), four (10%) were treated palliatively (non-surgery group), and two (5%) received no treatment. Intraoperative complications occurred in 11.8% with four (15.4%) postoperative deaths. Recurrence was detected in 28.6% at a median of 151 days (range, 79–684 days), while postoperative metastases were suspected in 21.4% at a median of 186 days (range, 79–479 days). The median survival time (MST) was significantly longer in cats of the surgery group (375 days) than in the non-surgery group (16 days) (p = .002). MST was 868 days for hepatocellular compared to 270 days for bile duct carcinomas (p = .06). In summary, liver lobectomy is associated with prolonged survival times and good prognosis in cats with hepatocellular, and an acceptable prognosis in cats with bile duct carcinoma.  相似文献   
120.
Abstract

Timber strength grading has become a major issue in the European Union during the last years, due to the introduction of the Eurocode 5 and all its related standards. Currently, the most performing strength grading machines are able to locally detect the boards’ knots sizes and positions and interpret this information through adapted grading models. The best lead to improve their accuracy seems to be the introduction of new information about the boards and adapt the mechanical model to take them in account. Small grain angle causes high reduction of clear wood's mechanical properties; local value of slope of grain appears to be of high interest. The aim of this study is to quantify the additional accuracy that grain angle information can bring to an optical scanner used as a strength grading machine. A specific grading model has been developed accordingly, and the results obtained for different machine/model/loading combinations are presented. These results show that slope of grain measurement can significantly improve the accuracy of the optical scanner, for both modulus of elasticity and modulus of rupture estimations.  相似文献   
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