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We present a case of aggressive metastatic carcinoma in a horse that was initially presented for shoulder lameness. Although radiography and scintigraphy were useful for localising a lesion in the proximal humerus, subsequent development of non-specific signs of systemic disease prompted further evaluation. Haematology and blood biochemistry, urinalysis and ultrasonography were all instrumental in identifying renal involvement. A diagnosis of a peri-renal mass causing secondary renal failure prompted euthanasia of the horse because of the poor prognosis. Antemortem findings were supported by necropsy, with secondary lesions also identified in the spleen, liver, 8th left rib and proximal humerus. Histological examination yielded a diagnosis of undifferentiated metastatic carcinoma.  相似文献   
86.
Four incidents of Duranta erecta (golden dewdrop, Sheena's Gold, Geisha Girl) poisoning affecting nine dogs and a cat produced drowsiness, hyperaesthesia and tetanic seizures in all affected animals with evidence of alimentary tract irritation (vomiting, gastric and intestinal haemorrhage, diarrhoea, melaena) in five dogs and the cat. Fruits and leaves were seen to be eaten by affected animals. Therapy was successful in three of the dogs. Repeated diazepam doses and, in some cases, additional pentobarbitone or propofol anaesthesia, were successful in controlling seizures.  相似文献   
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In a spatial regression context, scientists are often interested in a physical interpretation of components of the parametric covariance function. For example, spatial covariance parameter estimates in ecological settings have been interpreted to describe spatial heterogeneity or “patchiness” in a landscape that cannot be explained by measured covariates. In this article, we investigate the influence of the strength of spatial dependence on maximum likelihood (ML) and restricted maximum likelihood (REML) estimates of covariance parameters in an exponential-with-nugget model, and we also examine these influences under different sampling designs—specifically, lattice designs and more realistic random and cluster designs—at differing intensities of sampling (n=144 and 361). We find that neither ML nor REML estimates perform well when the range parameter and/or the nugget-to-sill ratio is large—ML tends to underestimate the autocorrelation function and REML produces highly variable estimates of the autocorrelation function. The best estimates of both the covariance parameters and the autocorrelation function come under the cluster sampling design and large sample sizes. As a motivating example, we consider a spatial model for stream sulfate concentration.  相似文献   
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Ovine mast cells generated in vitro from bone marrow (BMMC) were compared with mucosal mast cells (MMC) isolated from parasitised abomasum. Ultrastructurally, the granules of BMMC were partially developed and immature. Both cells types contained beta-hexosaminidase, arylsulfatase, histamine, dopamine and sheep mast cell proteinase (SMCP). Greater amounts of beta-hexosaminidase, but less SMCP, histamine and arylsulfatase were present in BMMC. Stimulation with calcium ionophore A23187 caused the secretion of granule constituents and generation of leukotriene C4 by BMMC in a dose-dependent manner. An additional [3H]diisopropylfluorophosphate-binding 31,500 mol. wt. serine esterase, antigenically related to SMCP (27,000 mol. wt.) was present in cultures of BMMC but was not detected in isolated MMC. Both enzymes were detected in BMMC by Day 7 of culture and were secreted concomitantly following stimulation of BMMC with ionophore.  相似文献   
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The current study examined the protective effects of l ‐glutamine and cytochalasin B during vitrification of immature bovine oocytes. Oocyte vitrification solution (PBS supplemented with 10% FCS, 25% EG, 25% DMSO and 0.5 m trehalose) was the vitrification control. Treatments were the addition of 7 μg/ml cytochalasin B, 80 mm glutamine or both cytochalasin and glutaminine for 30 s. After warming, oocytes were matured in vitro for 24 h, fixed and stained with Hoechst (33342) for nuclear maturation evaluation. l ‐glutamine improved the vitrified/warmed immature bovine oocytes viability (32.8%), increasing the nuclear maturation rates compared to other treatments and the no treatment vitrified control (17.4%). There was, however, no effect of cytochalasin B on in vitro maturation (14.4%).  相似文献   
90.
Computer simulations and experimental studies were combined to design copolymers that enhance the strength of polymer composites. These copolymers contain side chains that associate across the boundary between phase-separated regions to form a "molecular velcro" that effectively binds the regions together. This behavior significantly improves the structural integrity and mechanical properties of the material. Because the side chains can be fabricated from a large class of compounds, the technique greatly increases the variety of copolymers that can be used in forming high-strength polymer blends.  相似文献   
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