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101.
A 14-y-old spayed female Labrador Retriever was presented with an 8-mo history of chronic vomiting. Abdominal ultrasound and gastrointestinal endoscopy revealed a mass protruding into the gastric lumen, with cytologic features suggestive of sarcoma. A partial gastrectomy was performed; the gastric body and antrum were thickened, with a cerebriform appearance of the mucosal surface. Histologic examination revealed a submucosal neoplastic proliferation of fusiform cells variably arranged in irregular bundles and scattered whorls. Fusiform cells strongly reacted to antibodies against vimentin, S100, and neuron-specific enolase; glial fibrillary acidic protein was moderately and multifocally expressed. Pancytokeratin, KIT, α–smooth muscle actin, and desmin were nonreactive. Histologic and immunohistochemical findings suggested a diagnosis of gastric sarcoma with features referable to a non-GIST (gastrointestinal stromal tumor), non–smooth muscle NIMT (non-angiogenic, non-lymphogenic intestinal mesenchymal tumor). The overlying gastric mucosa was thickened by elongated and dilated gastric glands, predominantly lined by intensely periodic acid-Schiff–stained mucous cells. This altered mucosal architecture was suggestive of Ménétrier-like disease. Although this disease has been hypothesized to predispose to gastric adenocarcinoma in dogs, an association with gastric sarcoma has not been documented previously in the veterinary literature, to our knowledge.  相似文献   
102.
This report describes the characterisation of a monoclonal antibody (mAb), AB6, which recognises specifically a cluster of canine leukocyte surface molecules. The immunogen used for obtaining the AB6 mAb was a lysate of canine peripheral blood mononuclear cells (PBMC). This novel mAb belongs to the IgG2a isotype, and reacted in Western blot with four different canine leukocyte glycoproteins with apparent molecular weights of 180, 190, 205 and 220 kDa. The AB6 mAb recognised the majority of canine peripheral blood leukocytes as determined by flow cytometry (97%). It also exhibited a broad reactivity pattern against lymphoid and myeloid cells, inhibited the proliferation of mitogen-stimulated canine PBMC and did not recognise human PBMC and murine splenocytes. The biochemical properties, cell and tissue specificity, and in vitro biological activity of the AB6 mAb indicate that it recognises a canine CD45 homologue. The mAb could become a valuable diagnostic and research tool for the evaluation of immune functions in dogs.  相似文献   
103.
104.
The combined occurrence of ocular pigment deposition and glaucoma has been described in Cairn Terriers. Recently, this condition was also observed in two other breeds: the Boxer (two cases) and the Labrador Retriever (one case). Six dogs were referred to the Ophthalmology section of the Department of Clinical Sciences of Companion Animals and to a private referral clinic because of glaucoma or blindness in one or both eyes. In five cases ophthalmic examination showed pigment depositions in the sclera around the entire circumference of the perilimbal zone. Eight enucleated eyes (four eyes of two Cairn Terriers, three eyes of two Boxers and one eye of a Labrador Retriever) were examined microscopically. All eyes showed the same findings: an extensive infiltration of large melanin-containing cells with an eccentric nucleus, located in the iris, ciliary body, retina, choroids and sclera. Transmission electron microscopy of two of the examined eyes revealed that the morphology of most of these cells was consistent with melanophages. While reports in the veterinary literature concerning this condition are limited the cells concerned have been described to be melanocytes. Further research is needed to conclusively identify the cell type. As described in the present report, the histologic and transmission electron microscopic findings suggest a different etiology of the ocular pigment deposition and glaucoma compared with the pigment dispersal syndrome in humans.  相似文献   
105.
106.
Specific contrast ultrasound is widely applied in diagnostic procedures on humans but remains underused in veterinary medicine. The objective of this study was to evaluate the use of microbubble-based contrast for rapid ultrasonographic diagnosis of thrombosis in small animals, using male New Zealand white rabbits (average weight about 3.5 kg) as a model. It was hypothesized that the use of microbubble-based contrast agents will result in a faster and more precise diagnosis in our model of thrombosis. A pro-coagulant environment had been previously established by combining endothelial denudation and external vessel wall damage. Visualization of thrombi was achieved by application of contrast microbubbles [sterically stabilized, phospholipid-based microbubbles filled with sulfur hexafluoride (SF6) gas] and ultrasonography. As a result, rapid and clear diagnosis of thrombi in aorta abdominalis was achieved within 10 to 30 s (mean: 17.3 s) by applying microbubbles as an ultrasound contrast medium. In the control group, diagnosis was not possible or took 90 to 180 s. Therefore, sterically stabilized microbubbles were found to be a suitable contrast agent for the rapid diagnosis of thrombi in an experimental model in rabbits. This contrast agent could be of practical importance in small animal practice for rapid diagnosis of thrombosis.  相似文献   
107.

Background

The moose (Alces alces) is an intensively managed keystone species in Fennoscandia. Several aspects of reproduction in moose have not been fully elucidated, including puberty, timing of mating and oestrus, and the length of the oestrus period. These aspects are relevant for an adaptive management of moose with respect to harvest, population size, demography and environmental conditions. Therefore, an investigation of female moose reproduction was conducted during the moose-hunting period in southern Sweden from 2008 to 2011.

Results

A total of 250 reproductive organs and information on carcass weight and age was collected from four different hunting areas (provinces of Öland, Småland, Södermanland, and Västergötland) in southern Sweden. The results showed that puberty in female moose varied with carcass weight, age, and time of season. The period for oestrous/mating lasted from about mid September to the beginning of November.

Conclusions

The oestrus period (predominantly for heifers) is longer than previously reported and was not finished when the hunting period started. Sampling the uterine cervix to detect spermatozoa was a useful method to determine if mating had occurred. To avoid hunting of moose during oestrus, we suggest that the hunting period should be postponed by at least 14 days in southern Sweden.  相似文献   
108.
The aim of the present study was to determine the relationship of progesterone (P4), bovine pregnancy-associated glycoprotein-1 (bPAG-1) and nitric oxide (NO) levels with late embryonic (LEM; day 28 to day 42) and early fetal mortalities (EFM; > day 42 to day 56) in dairy cows. Transrectal ultrasonography (6–8 MHz) was performed in 100 Holstein-Friesian cows at days 28, 42 and 56 after artificial insemination (AI; day 0) to diagnose pregnancy and to monitor the fate of the embryo. After ultrasound scanning of each cow, a milk sample was collected for assessment of P4 by an ELISA test and a blood sample was collected for assessment of bPAG-1, by using a double-antibody radioimmunoassay, and serum NO metabolites (nitrate + nitrite). Based on ultrasonographic examinations and bPAG-1-RIA, 41 of 100 inseminated cows were confirmed pregnant at day 28 after AI. Nine cows suffered of LEM, and 6 cows suffered of EFM and the overall pregnancy loss rate was 36.6% (15/41) between days 28 and 56 of pregnancy. By logistic regression analysis, there were no significant relationships between the level of P4 and bPAG-1 at day 28 after AI and the occurrence of LEM and EFM. Also, there were no significant relationships between the levels of P4 and bPAG-1 at day 42 and the occurrence of EFM. On the other hand, a significant relationship (P<0.05) was found between NO level at day 28 and the occurrence of LEM. In conclusion, measurement of the serum NO concentration at day 28 of pregnancy might help to predict the outcome of pregnancy by day 42 in dairy cows but further studies are needed to confirm this.  相似文献   
109.
Cefuroxime axetil pharmacokinetic profile was investigated in 12 Beagle dogs after single intravenous and oral administration of tablets or suspension at a dose of 20 mg/kg, under both fasting and fed conditions. A three-period, three-treatment crossover study (IV, PO under fasting and fed condition) was applied. Blood samples were withdrawn at predetermined times over a 12-hr period. Cefuroxime plasma concentrations were determined by HPLC. Data were analyzed by compartmental analysis. No statistically significant differences were observed between formulations and feeding conditions on PK parameters. Independently of the feeding condition, absorption of cefuroxime axetil after tablet administration was low and erratic. The drug has been quantified in plasma in 3 out of 6 and 5 out of 6 dogs in the fasted and fed groups. For this formulation, the bioavailability (F), peak plasma concentration (Cmax), and area under the concentration–time curve (AUC) of cefuroxime axetil were significantly enhanced (p < .05) by the concomitant ingestion of food (32.97 ± 13.47–14.08 ± 7.79%, 6.30 ± 2.62–2.74 ± 0.66 µg/ml, and 15.75 ± 3.98–7.82 ± 2.76 µg.hr/ml for F, Cmax, and AUC in fed and fasted dogs, respectively), while for cefuroxime axetil suspension, feeding conditions affected only the rate of absorption, as reflected by the significantly shorter absorption half-life (T½(a)) and time to peak concentration (Tmax) (0.55 ± 0.27–1.15 ± 0.19 hr and 1.21 ± 0.22–1.70 ± 0.30 for T½(a) and Tmax in fed and fasted dogs, respectively). For cefuroxime axetil tablets, T > MIC (≤1 µg/ml) was <2 hr in fasted and ≈4 hr in fed animals, and for cefuroxime axetil suspension, T > MIC (≤1 µg/ml) was ≈5 hr and for T >MIC (≤4 µg/ml) was ≈2.5 hr for fasted and fed dogs, respectively. Cefuroxime axetil as a suspension formulation seems to be a better option than tablets. However, its short permanence in plasma could reduce its clinical usefulness in dogs.  相似文献   
110.
Pedigree dogs and cats are bred aiming to conform breed standards with very poor consideration for breeding stock fertility. At the same time, the genetic asset underlining reproductive traits could be effectively analysed like in other species under selection. The definition of selection targets is very important in breeding protocols determination. The aim of the present work is to present an overview of the different correlations between reproduction and genetics, starting from selection procedure and inbreeding coefficient moving to genomic and the application of SNPs and GWAS on population study and identification of genes involved in phenotypical variation of reproductive traits in dogs. Particular relevance has been given to the concept of inbreeding which effects on canine reproduction have been presented. The use of genomic information in inbreeding coefficient calculation can be considered an improved effective procedure in the evaluation of the genetic variability loss in canine population and its negative effects on reproductive traits.  相似文献   
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