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排序方式: 共有173条查询结果,搜索用时 15 毫秒
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Nødtvedt A Bergvall K Sallander M Egenvall A Emanuelson U Hedhammar A 《Veterinary dermatology》2007,18(5):309-315
Environmental and dietary risk factors for the development of canine atopic dermatitis (CAD) in the high-risk breeds of boxer, bullterrier and West Highland white terrier were assessed in a case-control study. A logistic regression model was developed to evaluate their relative importance in 58 cases from 12 practices in Sweden and 61 unaffected controls, matched to cases by breed and year of birth. The final model included a random error term for 'examining veterinarian', as dogs from the same practice were not considered independent. No effect of gender, season of birth, environment, vaccination or de-worming practices on the odds of developing CAD was detected. The main finding was that feeding a diet including noncommercial products to the bitch during lactation had a protective effect on the development of CAD in her offspring; the odds of developing CAD were twice as high among offspring from bitches that were not exposed to home-made/noncommercial diets [95% confidence interval (CI) of the odds ratio: 1.2-3.8]. The population attributable fraction for not feeding home-made diets to the lactating bitch was estimated as 0.4 (95% CI: 0.04-0.63). Randomized controlled clinical trials are needed to further support the finding of a potential protective role of diet in CAD development. 相似文献
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Introduction of non-native species, such as Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), can be a means of mitigating the effects of climate change by meeting the growing demand for biomass and high quality wood. The aim of this study was to investigate early growth, survival and damage from late-spring frost and winter desiccation. A provenance trial with four coastal and three interior provenances of Douglas-fir originating from British Columbia, Canada, was established in Southwest Sweden (56°43′N, 13°08′E). Seedling height, length of the leading shoot, and occurrence of frost damage, were measured after one, three, and six growing seasons. Timing of bud break in spring was also observed. The interior Douglas-fir were more frequently damaged by late-spring frost compared to the coastal Douglas-fir. The interior Douglas-fir still had a higher survival after six growing seasons compared to the coastal variety. All provenances were damaged by winter desiccation, but the provenances originating from the coastal area were more severely damaged. Choice of variety may reduce the risk for either late-spring frost or winter desiccation. 相似文献
137.
Wild boar populations up,numbers of hunters down? A review of trends and implications for Europe
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Giovanna Massei Jonas Kindberg Alain Licoppe Dragan Gačić Nikica Šprem Jiří Kamler Eric Baubet Ulf Hohmann Andrea Monaco Janis Ozoliņš Sandra Cellina Tomasz Podgórski Carlos Fonseca Nickolay Markov Boštjan Pokorny Carme Rosell András Náhlik 《Pest management science》2015,71(4):492-500
Across Europe, wild boar numbers increased in the 1960s–1970s but stabilised in the 1980s; recent evidence suggests that the numbers and impact of wild boar has grown steadily since the 1980s. As hunting is the main cause of mortality for this species, we reviewed wild boar hunting bags and hunter population trends in 18 European countries from 1982 to 2012. Hunting statistics and numbers of hunters were used as indicators of animal numbers and hunting pressure. The results confirmed that wild boar increased consistently throughout Europe, while the number of hunters remained relatively stable or declined in most countries. We conclude that recreational hunting is insufficient to limit wild boar population growth and that the relative impact of hunting on wild boar mortality had decreased. Other factors, such as mild winters, reforestation, intensification of crop production, supplementary feeding and compensatory population responses of wild boar to hunting pressure might also explain population growth. As populations continue to grow, more human–wild boar conflicts are expected unless this trend is reversed. New interdisciplinary approaches are urgently required to mitigate human–wild boar conflicts, which are otherwise destined to grow further. © 2014 Crown copyright. Pest Management Science © 2014 Society of Chemical Industry 相似文献
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Ulf Geisen Marion Zenthoefer Matthias Peipp Jannik Kerber Johannes Plenge Antonella Managò Markus Fuhrmann Roland Geyer Steffen Hennig Dieter Adam Levent Piker Gerald Rimbach Holger Kalthoff 《Marine drugs》2015,13(7):4470-4491
Pancreatic cancer is one of the most aggressive cancer entities, with an extremely poor 5-year survival rate. Therefore, novel therapeutic agents with specific modes of action are urgently needed. Marine organisms represent a promising source to identify new pharmacologically active substances. Secondary metabolites derived from marine algae are of particular interest. The present work describes cellular and molecular mechanisms induced by an HPLC-fractionated, hydrophilic extract derived from the Baltic brown seaweed Fucus vesiculosus (Fv1). Treatment with Fv1 resulted in a strong inhibition of viability in various pancreatic cancer cell lines. This extract inhibited the cell cycle of proliferating cells due to the up-regulation of cell cycle inhibitors, shown on the mRNA (microarray data) and protein level. As a result, cells were dying in a caspase-independent manner. Experiments with non-dividing cells showed that proliferation is a prerequisite for the effectiveness of Fv1. Importantly, Fv1 showed low cytotoxic activity against non-malignant resting T cells and terminally differentiated cells like erythrocytes. Interestingly, accelerated killing effects were observed in combination with inhibitors of autophagy. Our in vitro data suggest that Fv1 may represent a promising new agent that deserves further development towards clinical application. 相似文献
139.
Mapari SA Hansen ME Meyer AS Thrane U 《Journal of agricultural and food chemistry》2008,56(21):9981-9989
Monascus pigments have been used as natural food colorants in Asia for centuries. They are not authorized for use in the European Union and the United States mainly due to the risk of coproduction of the mycotoxin citrinin by Monascus spp. In the present study, we screened for novel producers of Monascus-like pigments from ascomycetous filamentous fungi belonging to Penicillium subgenus Biverticillium that are not reported to produce citrinin or any other known mycotoxins. The screening was carried out using the X-hitting algorithm as a tool to quickly screen through chromatographic sample data files of 22 different Penicillium extracts with 12 Monascus pigment extracts as controls. The algorithm searched for the most similar UV-vis spectra of the metabolites (cross hits) present in the pigment extracts to those of the selected reference metabolites viz. monascin, rubropunctatin, rubropunctamine, and citrinin. The cross hits were then manually identified on the basis of their UV-vis and mass spectra. X-hitting was found to be a good tool in the rapid screening of crude pigment extracts. Monascus pigments were discovered in the extracts of two closely related species of Penicillium that were only distantly related to the genus Monascus. Monascorubrin, xanthomonasin A, and threonine derivatives of rubropunctatin were identified in the extract of Penicillium aculeatum IBT 14263, and monascorubrin was identified in the extract of Penicillium pinophilum IBT 13104. None of the tested Penicillium extracts showed the presence of citrinin. Thus, the present study brought out two novel promising sources of yellow, orange, and purple-red Monascus-like food pigments in the species of Penicillia that do not produce citrinin and opened the door to look for several more new promising sources of natural food colorants in the species of Penicillia. 相似文献
140.
Since the mid-1990s, the cultivation of white lupin (Lupinus albus L.) has rapidly decreased in Germany and other countries in Central Europe because of the occurrence of Colletotrichum lupini, the causal agent of the fungal disease anthracnose, and the lack of varieties with a sufficient resistance towards this disease. To reestablish the relevance of cultivating white lupins, the development of new varieties with improved resistance is vital. In the study presented here, new breeding lines were evaluated from 2012 to 2014 on a total of five experimental sites in Germany. In each year, at least on one site a high disease pressure with good differentiation built up from natural seed infestations, so that evaluation and further selection for resistance was possible in all 3 years. The breeding lines showed improved performance of resistance towards C. lupini (anthracnose disease score 3.8 on average of all breeding lines and environments) compared to the reference varieties (anthracnose disease score 5.8). Improved resistance had a favorable effect on grain yield, particularly in environments with high disease pressure, and yield stability. Average grain yields were 2.6 t ha?1 for the breeding lines and 1.5 t ha?1 for the reference cultivars. Among the tested range of white lupins, the breeding material showed consistently higher grain yields on average of all environments compared to the rather low and variable yielding reference cultivars. The alkaloid content varied among environments and breeding lines. 相似文献