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51.
Morphological and biochemical aspects of apoptosis,oncosis and necrosis   总被引:39,自引:0,他引:39  
Recent investigations have demonstrated the need for a precise differentiation of various forms of cell death such as apoptosis, oncosis, necrosis and programmed cell death. Apoptosis is marked by cellular shrinking, condensation and margination of the chromatin and ruffling of the plasma membrane with eventually breaking up of the cell in apoptotic bodies. Cell death marked by cellular swelling should be called oncosis, whereas the term necrosis refers to the morphological alterations appearing after cell death. Apoptosis and oncosis are therefore pre-mortal processes, while necrosis is a post-mortal condition. The term programmed cell death refers to the 'fixed' pathway followed by dying cells, whether or not with the characteristic morphology of apoptosis. Three mechanisms are actually known to be involved in the apoptotic process: a receptor-ligand mediated mechanism, a mitochondrial pathway and a mechanism in which the endoplasmic reticulum plays a central role. All three mechanisms activate caspases which are responsible for the characteristic morphological changes observed during apoptosis. A review of the different methods used for detecting apoptotic cells demonstrates that most of these techniques are not entirely specific.  相似文献   
52.
Emesis is a common presenting sign in small animal practice. It requires a rational approach to management that is based upon a sound understanding of pathophysiology combined with logical decision making. This review, which assesses the weight of available evidence, outlines the physiology of the vomiting reflex, causes of emesis, the consequences of emesis and the approach to clinical management of the vomiting dog. The applicability of diagnostic testing modalities and the merit of traditional approaches to management, such as dietary changes, are discussed. The role and usefulness of both traditional and novel anti-emetic drugs is examined, including in specific circumstances such as following cytotoxic drug treatment. The review also examines areas in which common clinical practice is not necessarily supported by objective evidence and, as such, highlights questions worthy of further clinical research.  相似文献   
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The aim of this study was to assess the effects of a standard therapeutic protocol of prednisolone (Pred) on glucose homeostasis in atopic dogs and compare it with previously published data for ciclosporin A (CsA). The central aim of the study was to assess and compare the effects of standard therapeutic protocols of prednisolone (Pred) and ciclosporin A (CsA) on glucose homeostasis in dogs with atopic dermatitis (CAD). Both treatments significantly reduced the physical signs of CAD, as determined by the canine atopic dermatitis extent and severity index version 3 (CADESI-03) and the Edinburgh Pruritus Scale (EPS). Post-treatment plasma glucose concentrations were not significantly different in the two groups, but serum insulin concentrations were significantly higher following Pred therapy (P<0.05). Serum fructosamine concentrations were not significantly different pre- and post-treatment with Pred, although previous studies had shown that CsA treatment increased fructosamine concentrations (P<0.005). The two treatment groups were recruited in a similar timeframe, were numerically matched and there were no differences in CADESI-03 and EPS scores between the CsA and Pred groups either before or after treatment. Thus, both CsA and Pred treatment were associated with mild disturbances in glucose metabolism, but only CsA therapy resulted in a significant increase in fructosamine concentrations. This information may be relevant to clinicians when considering therapeutic options for dogs with atopic dermatitis which already have impaired glucose homeostasis.  相似文献   
55.
对自然保护区3只患皮肤病岩羊进行临床检查、病原分离鉴定、血细胞常规测定和病理解剖学观察,确诊为岩羊患疥螨病致死。  相似文献   
56.
In this article, frequently encountered statistical questions and methods used both in research and in daily practice are described and explained. First, the concepts of variability and uncertainty are explained and illustrated. From this, it is explained how variation can be quantified and how the limits of what can be expected as a result of normal variation are determined both for continuous and binary data. Based on the basic concepts of probability theory, an introduction to risk assessment was given. Finally it is explained how to test whether individual observations lie outside the normal range or the test whether populations are different from each other. All these are carried out avoiding theory and formulas as much as possible and illustrated with real examples from reproduction and herd health.  相似文献   
57.
High‐yielding dairy cows are struggling with a high incidence of embryonic loss, among others caused by an insufficient peripheral progesterone concentration which for its part might be associated with an impaired luteal progesterone production. This impaired capacity to produce progesterone might be reflected in the histology of the gland. The aim of the present pilot study was the assessment of the variation in cell density within a bovine luteal gland (LG), to examine whether it is possible to analyse histologically the functionality of the gland based on one single tissue sample. Six LGs (stage II or III) were harvested out of just as many healthy cows at the slaughterhouse. The luteal cell density was assessed by calculating the nuclear density (ND) of the different luteal cell types on haematoxylin‐eosin‐stained histological sections from a number of topographic regions evenly spread throughout the glands, to give an overview of the pattern of cellular distribution within the whole gland. Cells were differentiated into ‘large luteal cells’, ‘small luteal cells’ and ‘non‐steroidogenic cells’. Results show that the cellular density, within a tissue sample is not significantly influenced by its location in relation to the gland's equatorial plane. However, the position with respect to the polar axis of the gland has a decisive effect, as the ND is significantly higher (p < 0.05) in the peripheral regions (outer zone) when compared with the central regions (inner zone) of the gland, and this counts for all three cell types.  相似文献   
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An Internet-based questionnaire among horse owners was carried out to identify factors affecting the incidence of insect bite hypersensitivity (IBHI) among horses in the Netherlands. Information was obtained for 794 horses of various breeds, but the breed distribution was not representative for the Dutch horse population. Of the horses for which information was available, 56% suffered from IBH and 44% did not. The most common clinical symptoms were pruritus, scaling, and hair loss, occurring mainly at the base of the tail and along the mane. Breed, age, region (and local habitat), stabling, type of bedding in the stable, use of the horse, deworming frequency, and season were associated with significant differences in IBH incidence. Knowledge of the factors influencing the incidence of IBH may make it possible to reduce the number of animals affected and help alleviate symptoms in affected horses.  相似文献   
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