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Ultrasonography is a valuable tool for the evaluation of neoplastic lesions in the dog and there is a growing interest in the use of this technique for the stadiation of canine mammary tumours. An accurate assessment of small sized nodules facilitates the stadiation of the mammary lesions and helps the clinician in the choice of the most indicated surgical therapy. The aim of this study was to identify those ultrasound criteria that may be useful in discriminating between benign and malignant lesions of small size (diameter smaller than 2 cm). Sixty-two nodules, < 2 cm in larger diameter, belonging to thirty-five bitches presented between January 2012 and February 2014 were evaluated. Tumours were observed by conventional ultrasound and assessed for: shape (regular-irregular), limit (defined-ill-defined), margins (regular-irregular), echogenicity (hypoechoic-isoechoic-hyperecoic), echotexture (homogeneus-heterogeneus), presence of hyperecoic halo, distal acoustic enhancement or shadowing and surrounding tissue alterations. Among the alterations in surrounding tissues, the disruption of the glandular tissue and the increase in echogenicity of the peritumoral tissues were assessed. Thereafter, bitches were subjected to mastectomy and nodules were evaluated histologically. None of the ultasound criteria considered in the current study showed a statistically significant relation with malignancy, except for the presence of alterations in the tissue surrounding the nodules. According to our results, this characteristic may indicate malignancy, however its subjectivity may affect the applicability in clinical practice. In conclusions, conventional ultrasound in bitches had a limited ability in discriminating benign and malignant mammary gland neoplastic lesions of small size (diameter?<?2 cm).  相似文献   
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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   
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Innate and acquired immune responses of Gilthead Seabream Sparus aurata was studied under normal culture and short-term stressful conditions for 18 months in offshore sea cages in Alghero Bay, Italy. Every 45 d, 50 fish were sampled and divided into two groups: fish in the first group (normal culture conditions) were bled after harvesting; fish in the second group were put into a tank under stressful conditions (crowding and confinement) and bled after 2 h. Innate humoral immunity, such as complement-like, hemagglutination, and lysozyme activities, was determined in the sera of both groups. Pathogen challenge was not performed, but the specific humoral immune response was assessed against the most common pathogens affecting cultured fish in Sardinia. Stressed fish, compared with the control, showed a lower lysozyme activity against Vibrio (Listonella) anguillarum, which was not clearly correlated with temperatures. Complement-like activity differed between the first and second half of the study and, at the end of the trial, a slightly higher activity was recorded in the controls than in the stressed fish. Hemagglutination activity was mainly higher in the stressed fish than in control fish. Confinement, crowding, and cold water temperature caused decreased lysozyme activity in short-term stressed Gilthead Seabream compared with those reared normally. The specific humoral immune response, against V. anguillarum, Tenacibaculum mesophilum, Enterococcus Seriolicida, and Aeromonas sobria, fluctuated during the rearing period, particularly during the first year of culture.

Received October 12, 2015; accepted March 24, 2016 Published online August 2, 2016  相似文献   

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