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The repeatability of ultrasonographic measurements of the canine thyroid gland was evaluated. The variability of three different parameters (the maximal length, width, and height) within observer, between observer and between dogs was assessed based on three different measurements made by each of three observers infive healthy beagle dogs. From the three parameters, the volume of the gland was estimated using a formula of a rotation ellipse. The height and the volume had the lowest intra- and interobserver variability, while measurements of the length had the biggest intra- and interobserver variability. The mean values, with their 90% confidence interval were: height = 0.53cm [0.33-0.73], length = 2.45cm [2.04-2.85], width = 0.62cm [0.46- 0.78], volume = 0.38 cm3 [0.20-0.55].  相似文献   
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A male specific bovine DNA fragment was used as probe to determine the sex of bovine interphase cells by in situ hybridization. This method also proved useful for determining the sex of bovine embryos.  相似文献   
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Neuroendocrine-immune interactions in fish: a role for interleukin-1   总被引:10,自引:0,他引:10  
Bi-directional communication between the hypothalamus-pituitary-adrenal (HPA)-axis and the sympathetic nervous system with the immune system is crucial to ensure homeostasis. Shared use of ligands and especially receptors forms a key component of this bi-directional interaction. Glucocorticoids (GC), the major end products of the HPA-axis differentially modulate immune function. Cytokines, especially interleukin-1 (IL-1), tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6), ensure immune signalling to the neuroendocrine system. In addition, hormones from leukocyte origin such as corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH) and beta-endorphin, as well as centrally synthesised and secreted cytokines, contribute to the communication network.In teleost fish cortisol is the major product of the hypothalamus-pituitary-interrenal (HPI)-axis which is the teleost equivalent of the HPA-axis. Moderate and substantial increases in cortisol during stressful circumstances negatively affect B-lymphocytes, whereas rescue of neutrophilic granulocytes may support innate immunity. Recent elucidation of lower vertebrate cytokine sequences has facilitated research into neuroendocrine-immune interactions in teleosts and the first evidence for a significant function of interleukin-1 in the bi-directional communication is discussed.  相似文献   
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Heart rate is a major factor influencing diagnostic image quality in computed tomographic coronary artery angiography (MDCT‐CA), with an ideal heart rate of 60–65 beats/min in humans. The purpose of this prospective study was to compare effects of two different clinically applicable anesthetic protocols on cardiovascular parameters and 64‐MDCT‐CA quality in 10 healthy dogs. Scan protocols and bolus volumes were standardized. Image evaluations were performed in random order by a board‐certified veterinary radiologist who was unaware of anesthetic protocols used. Heart rate during image acquisition did not differ between protocols (P = 1), with 80.6 ± 7.5 bpm for protocol A and 79.2 ± 14.2 bpm for protocol B. Mean blood pressure was significantly higher (P > 0.05) using protocol B (protocol A 62.9 ± 9.1 vs. protocol B 72.4 ± 15.9 mmHg). The R‐R intervals allowing for best depiction of individual coronary artery segments were found in the end diastolic period and varied between the 70% and 95% interval. Diagnostic quality was rated excellent, good, and moderate in the majority of the segments evaluated, with higher scores given for more proximal segments and lower for more distal segments, respectively. Blur was the most commonly observed artifact and mainly affected the distal segments. No significant differences were identified between the two protocols for optimal reconstruction interval, diagnostic quality and measured length individual segments, or proximal diameter of the coronary arteries (P = 1). Findings indicated that, when used with a standardized bolus volume, both of these anesthetic protocols yielded diagnostic quality coronary 64‐MDCT‐CA exams in healthy dogs.  相似文献   
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Betanodaviruses are the causative agents of viral nervous necrosis (VNN), a serious disease of cultured marine fish worldwide. Virus-like particles (VLPs) are one of the good novel vaccine candidates to control this disease. Until now, betanodavirus vaccine studies mainly focused on the humoral immune response and mortality after virus challenge. However, little is known about the activation of genes responsible for cellular and innate immunity by vaccines. In the present study, VLPs of orange-spotted grouper nervous necrosis virus (OGNNV) were produced in prokaryotes and their ability to enter Asian sea bass cells was the same as native virus, suggesting that they possess a similar structure to OGNNV. VLPs immunogenicity was then determined by intramuscularly vaccinating Epinephelus coioides at different concentrations (1.5 or 15 μg g?1 fish body weight, FBW) and immunizing frequencies (administration once, twice and thrice). A single vaccination with the dosage of 1.5 μg g?1 FBW is enough to provoke high titer antibodies (average 3 fold higher than that of negative control) with strong neutralizing antibody titer as early as 1 week post immunization. Furthermore, quantitative PCR analysis revealed that eleven genes associated with humoral, cellular and innate immunities were up-regulated in the liver, spleen and head kidney at 12 h post immunization, correlating with the early antibody response. In conclusion, we demonstrated that VLP vaccination induced humoral immune responses and activated genes associated with cellular and innate immunity against betanodavirus infection in orange-spotted grouper.  相似文献   
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A 4‐year‐old, female spayed Domestic Shorthair cat was presented for a 2‐day history of lethargy, anorexia, and vomiting. Diagnostic assessments revealed a severe, regenerative anemia and the presence of a solitary, 3 × 4 cm splenic mass. Cytologic examination of fine‐needle aspirates of the splenic mass showed sheets of pleomorphic histiocytic cells with numerous intracellular and extracellular, negatively staining to deeply basophilic, branching structures. These structures were typically of thin uniform thickness with random angled branching that formed geometrical shapes and fragments, occasionally with sharpened ends and a crystalline appearance. Septal‐like divisions were irregularly spaced along some of the linear branches. The cytology was interpreted as a probable histiocytic inflammatory response to the unidentified foreign material with histiocytic sarcoma as a differential diagnosis. Histopathologic evaluation of the splenic mass resulted in a diagnosis of histiocytic sarcoma. The branching material stained positively for both iron and calcium, indicating that the material was compatible with Gamna‐Gandy bodies present secondary to tumor‐associated hemorrhage and the formation of calcium–iron complexes.  相似文献   
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