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29 samples of commonly used surfaces were tested for their water characteristics (litre weight, water capacity, water binding, water evaporation) and their contribution to airborne fungal spores (dust formation, dust setting). The results are discussed in comparison to the literature with regard to the environment. The results are: 1. Any surface--no matter of what material--eventually causes air pollution with fungal spores and dust. 2. Correct watering prevents air pollution by any surface. 3. Artificial products have no advantage over natural materials in the parameters tested. 4. The question of proper disposal of old surface material has to be clarified before purchase. The results show that a mixture of sand and wood shavings should be recommended as a surface for indoor arenas, especially in regard to environmental protection and proper disposal.  相似文献   
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Haematological and biochemical investigations were performed on 14 koalas with uncomplicated cystitis, 8 with complicated cystitis, 8 with conjunctivitis, 8 with lymphosarcoma, and 14 with miscellaneous diseases. Changes were limited and inconsistent in individual koalas with uncomplicated cystitis and conjunctivitis. In contrast, individual koalas with complicated cystitis were more likely to have anaemia, leukocytosis due to neutrophilia, hypoproteinaemia due to hypoalbuminaemia, and azotaemia due to elevated urea concentration. Although these changes were non-specific they did allow assessment of prognosis for survival and response to treatment. Koalas with lymphosarcoma were invariably anaemic, leukaemic, azotaemic and hypoalbuminaemic. Elevated enzymes (aspartate transaminase [AST]. lactate dehydrogenase [LD] and gamma glutamyl transferase [GGT]) were more common in koalas with lymphosarcoma. Koalas affected by miscellaneous conditions showed variable changes but once again anaemia, leukocytosis, azotaemia, elevated AST and LD, and hypoalbuminaemia were not uncommon. On the basis of these findings a minimal profile is suggested for the investigation of sick koalas and would include haematocrit, total and differential leukocyte counts, urea, total protein and albumin concentrations and AST, GGT and LD activities.  相似文献   
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Stress, stressors and the stress response are terms which represent concepts rather than oeing precisely definable. No single theory of stress has been universally accepted. Selye's General Adaptation Syndrome of stress remains the primary theory for the basis of stress research in food-producing animals; however, other concepts and theories have been developed. This paper reviews current theories and suggests that the complexity of research on stress in food-producing animals can be attributed to the lack of concrete theories and concepts regarding identifiable stressors, the endocrine responses stimulated by potential stressors and the complex and integrated biological changes in the neuro-endocrine system resulting from exposure to hypothesized stressors.  相似文献   
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Bilateral third degree burns were created on the flanks of eight miniature swine. Each animal had one side treated daily with low intensity direct (LIDC) of 400 microamperes (muA) by contact electrode for 2 hours morning and afternoon until healing occurred. The polarity of the electrode was negative in 4 pigs and positive in 4 pigs. One group of 4 pigs had the eschar surgically removed 24 hours post burn. Weekly biopsies and cultures were taken of treated and control wounds. Results indicated: local treatment of 400 muA LIDC did not hasten or delay healing of thermal third degree burns; escharectomy hastened wound healing by 10 days, and superficial proteus infection occurred in 80% of all wounds.  相似文献   
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Mycosporine-like amino acids (MAAs), a group of small secondary metabolites found in algae, cyanobacteria, lichens and fungi, have become ecologically and pharmacologically relevant because of their pronounced UV-absorbing and photo-protective potential. Their analytical characterization is generally achieved by reversed phase HPLC and the compounds are often quantified based on molar extinction coefficients. As an alternative approach, in our study a fully validated hydrophilic interaction liquid chromatography (HILIC) method is presented. It enables the precise quantification of several analytes with adequate retention times in a single run, and can be coupled directly to MS. Excellent linear correlation coefficients (R2 > 0.9991) were obtained, with limit of detection (LOD) values ranging from 0.16 to 0.43 µg/mL. Furthermore, the assay was found to be accurate (recovery rates from 89.8% to 104.1%) and precise (intra-day precision: 5.6%, inter-day precision ≤6.6%). Several algae were assayed for their content of known MAAs like porphyra-334, shinorine, and palythine. Liquid chromatography-mass spectrometry (LC-MS) data indicated a novel compound in some of them, which could be isolated from the marine species Catenella repens and structurally elucidated by nuclear magnetic resonance spectroscopy (NMR) as (E)-3-hydroxy-2-((5-hydroxy-5-(hydroxymethyl)-2-methoxy-3-((2-sulfoethyl)amino)cyclohex-2-en-1-ylidene)amino) propanoic acid, a novel MAA called catenelline.  相似文献   
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