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排序方式: 共有149条查询结果,搜索用时 250 毫秒
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Burkhardt RW 《Science (New York, N.Y.)》1983,222(4620):156-157
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Pees MC Kiefer I Ludewig EW Schumacher JP Krautwald-Junghanns ME Oechtering GU 《American journal of veterinary research》2007,68(4):428-434
OBJECTIVE: To evaluate the use of computed tomography (CT) for detection of pneumonia in snakes. ANIMALS: 8 clinically normal Indian pythons (Python molurus) and 5 pythons with evidence of respiratory tract disease. PROCEDURES: Preliminary examinations (clinical examination, conventional radiography, and microbiologic examination of a transtracheal wash sample) were performed. The lungs of each snake were then examined by use of CT performed in accordance with a standardized protocol. Structures of the lungs were assessed, and thickness and attenuation of the parenchyma were determined. RESULTS: It was possible to assess lung parenchyma in all pythons. Mean +/- SD attenuation in healthy pythons was -744.4 +/- 47.1 Hounsfield units. Significant differences were not evident between the right and left lungs or among measurement areas within a lung. In all Indian pythons with clinical signs of dyspnea and microbiologic detection of pathogens, hyperattenuation of the alveolar tissue was evident. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of the results revealed the benefit of CT for use in the diagnosis of pneumonia in snakes. A standardized protocol and reference values were established as a basis for CT assessment of the lungs of snakes. 相似文献
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Eric Klaphake Ahmed Shoieb Ed Ramsay Juergen Schumacher Linden Craig 《Journal of zoo and wildlife medicine》2005,36(1):127-130
A 19-yr-old binturong (Arctictis binturong) with acute upper respiratory disease was euthanized. Postmortem findings included hepatocellular carcinoma, pancreatic islet cell carcinoma, and renal adenocarcinoma with metastasis to the spleen, pleura, and pericardium. A link between primary hepatic and renal neoplasms has been noted in older humans. 相似文献
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The cell-mediated immune response of blood lymphocytes from 110 untreated dogs with different tumours was evaluated. The influence of different tumour types on the cellular immune system was examined by assessing the percentage of isolated large granular lymphocytes (LGL), in vitro natural cytotoxicity and mitogen-induced lymphocyte proliferation. Although the overall natural cytotoxicity of dogs with different tumours was decreased, the overall difference from control values was not statistically significant. However, mitogen-induced lymphocyte proliferation was significantly depressed in dogs with tumours in comparison with the controls. Dogs with mammary carcinomas showed significantly lower natural cytotoxicity than controls and dogs with myeloid neoplasms showed significantly lower mitogen-induced lymphocyte proliferation. Abnormalities exist not only in natural cytotoxicity but also in mitogen-induced lymphocyte proliferation. For the dog, this is the first study to assess the influence of different tumours using a combined evaluation of natural cytotoxicity and mitogen-induced lymphocyte proliferation in such a large number of animals. 相似文献
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Due to the growing interest in the role of carotenoids in human health, their qualitative and quantitative analysis in foods is becoming more and more important. High-performance liquid chromatography has become the method of choice for the determination of these phytochemicals. A crucial step prior to the chromatographic separation is the quantitative extraction from the food matrix which was proven to be impeded in durum wheat. To optimize the extraction procedure, several factors with influence on extractability of carotenoids were investigated. Finally, it was shown that soaking of samples in water for 5 min prior to extraction with organic solvents had the strongest impact on extraction yield and led to the most rapid and gentle method. Contents of carotenoids in the extracts of several durum wheat and corn samples were doubled by soaking in water before extracting with methanol/tetrahydrofuran (1/1, v/v). In light of these findings, literature data on contents of carotenoids in cereal grains have to be viewed critically regarding the extraction procedures employed. 相似文献
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Daniel Thiel Juergen Kreyling Sabrina Backhaus Carl Beierkuhnlein Constanze Buhk Kolja Egen Gerhard Huber Monika Konnert Laura Nagy Anke Jentsch 《European Journal of Forest Research》2014,133(2):247-260
Climate extremes are expected to increase in frequency and magnitude as a consequence of global warming, threatening the functioning, services and goods of forest ecosystems. Across Europe, the ecologically and economically important tree species Fagus sylvatica is expected to suffer particularly under such conditions. The regional introduction of provenances from drier and warmer climates is one option to adapt beech forest ecosystems to these adverse effects of climate change. Marginal populations from the drought-prone southern and north-eastern edges of the species’ distribution come into focus in search of suitable candidates for Central European deciduous forests. Here, we test three marginal provenances (Spain, Bulgaria and Poland) and three provenances from the centre of the distribution range (Germany) for their response to drought in two different soil types (sand, loam) in a full factorial common garden experiment in Landau, Germany. Drought impacted all growth parameters negatively (leaf damage +22 % (percentage points), height ?40 % and diameter increment ?41 %), and the sandy substrate exacerbated this effect. However, provenances differed in their response to drought and soil type. Evidence for a local adaptation to summer drought was detected, especially in terms of mortality rates. The Bulgarian and Spanish provenance showed a stable performance under drought conditions (BG ?27 % in diameter increment; ES ?32 %), compared to the Polish (?48 %) or the most sensitive German provenances (?57 %), yet for Bulgaria on a low level of total increment. This may indicate a trade-off between drought tolerance and growth. Therefore, a sole focus on drought-resistant marginal provenances seems to not be conducive, as they might be less adapted to other climatic factors, e.g. frost, as well. However, intermixed with local Central European provenances, these may act as functional insurance in future drought-prone forest stands. 相似文献
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Thermal stratification negatively affects water quality, and thus is a threatto fish culture in deep water ponds and reservoirs. To prevent and controlit, a device based on an underwater propeller that vertically transportsoxygen rich warm water from the epilimnion down to the anoxic and colderhypolimnion was assembled. The empirical results so far obtained in Israelidual purpose reservoirs for field crop irrigation and fish culture aresummarized herein, and a mathematical model of the device's effect onreservoir thermal structure is presented. 相似文献
10.
P Rüsch M Berchtold H Burkhardt A Mittelholzer 《DTW. Deutsche tier?rztliche Wochenschrift》1990,97(10):385-386
In cows with teat lesions, partial drying-off of the affected mammary quarter is recommended for a period of 3 to 10 days. The other three quarters are normally milked. Partial drying-off reduces the risks of complications due to the daily milking. The slight reduction of milk production, connected with the temporary drying-off a single quarter, is nearly compensated within 4 weeks. 相似文献