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901.
Orri Thor Ormarsson Thormodur Geirsson Einar Stefan Bjornsson Tomas Jonsson Pall Moller Thorsteinn Loftsson Einar Stefansson 《Marine drugs》2012,10(9):2047-2054
Cod-liver oil and other marine products containing polyunsaturated fatty acids have anti-inflammatory, anti-bacterial and anti-viral effects and may be useful in the treatment of various inflammatory and infectious diseases. We developed suppositories and ointment with 30% free fatty acid (FFA) extract from omega-3 fish oil. Our purpose was to evaluate the safety of marine lipid suppositories and ointment in healthy volunteers and to explore the laxative effect of the suppositories. Thirty healthy volunteers were randomized either to a study group administrating 30% FFA suppositories and applying 30% FFA ointment to the perianal region twice per day for two weeks, or to a control group using placebo suppositories and ointment in a double blinded manner. Results: No serious toxic effects or irritation were observed. In the study group 93% felt the urge to defecate after administration of the suppositories as compared to 37% in the control group (P = 0.001). Subsequently 90% in the study group defecated, compared to 33% in the control group (P = 0.001). Conclusion: The marine lipid suppositories and ointment were well tolerated with no significant toxic side effects observed during the study period. The suppositories have a distinct laxative effect and we aim to explore this effect in further clinical trials. 相似文献
902.
Stefan Skori? Bo?idar Ra?kovi? Vesna Poleksi? Zoran Ga?i? Mirjana Lenhardt 《Aquaculture International》2012,20(3):525-535
Cormorants cause damage to fish in aquaculture not only by consuming large number of fish but also by wounding them. Quantification of the actual damage in fish induced by wounding is important for reliable estimations of the overall loss in aquaculture caused by cormorants. In this study, specimens of mirror and scaly carp (Cyprinus carpio L.) injured by attacks of great cormorant (Phalacrocorax carbo L.) were collected from the ??E?ka?? fish farm in Serbia. Surfaces of superficial and open subepithelial wounds (expressed as a percent of the total body surface), estimated by computer-assisted image analysis, had mean values 10.66?±?1.86 and 0.85?±?0.90, respectively. Histological evaluation of wounds was performed by two scoring systems: system proposed by Bernet et al. (J Fish Dis 22:25?C34, 1999) and modified system described by Wahli et al. (Aquaculture 225:371?C386, 2003). The most frequent histopathological changes were disturbed epidermal structure and surface cell morphology and increased number of club cells (on more than 75% of specimens); increased number of melanocytes and their distribution in different layers in dermis; and enlarged hypodermis (more than 80% of samples) and myolysis (50% of samples). Comparison of wounds?? surfaces (surface of superficial injures) and histopathological changes, estimated by two scoring systems, revealed significant positive correlation. Bernet??s scoring system showed higher correlation coefficients, when compared with the modified Wahli??s scoring system. 相似文献
903.
Xiaoli Jin Stefan Harasymow Yumiko Bonnardeaux Allen Tarr Rudi Appels Reg Lance Guoping Zhang Chengdao Li 《Journal of Cereal Science》2011,53(2):149-153
Lipoxygenase (LOX) is a key factor affecting quality of beer in terms of foam stability and flavour. Low LOX content is a desirable trait for malting quality. A doubled haploid (DH) population was made from a cross of Australian malting barley Stirling and Canadian malting barley Harrington and mapped with 513 molecular markers. The 120 DH lines with their parents were planted in field trials and the harvested grains were micro-malted for analysis of LOX content in two consecutive years. LOX content was controlled by both genetic effects and environment conditions. Three QTLs were consistently detected. One QTL flanked by the markers E6216 and SCssr03907 at the telomere region of chromosome 5HL contributed 39% of genetic variation in LOX content. The second QTL close to the centromere region of chromosome 5H accounted for 17% of genetic variation. A minor QTL on chromosome 2H explained 6% of genetic variation but was significant in both years. The Australian variety Stirling contributed to higher LOX content for the three QTLs. The two QTLs mapped at chromosome 5H for LOX content coincided with the QTLs for seed dormancy/pre-harvest sprouting from the same population. The pre-harvest sprouting susceptible alleles were associated with low LOX content, which indicated that the low LOX QTL from the Canadian malting barleys are only useful in the barley growing areas where the pre-harvest sprouting risk is low. New genetic sources for low LOX should be exploited in different germplasm with different mechanisms. 相似文献
904.
Cheng Zong Lucas A. Wauters Stefan Van Dongen Veronica Mari Claudia Romeo Adriano Martinoli Damiano Preatoni Guido Tosi 《Forest Ecology and Management》2010
Seed predation and dispersal are key processes in the survival and distribution of plant species. Many animals cache seeds for later consumption, and, failing to recover some of these seeds, act as seed dispersers, influencing post-dispersal seed and seedling survival. Both animal and plant benefit from scatterhoarding and natural selection of seed characteristics and adaptations of seed predators (and dispersers) is one of the most important examples of co-evolution and mutualism. We studied the producer–consumer Arolla pine (Pinus cembra)–red squirrel (Sciurus vulgaris) system in a subalpine forest in the Italian Alps. Arolla pine produced large seed-crops (masting) at irregular intervals, followed by years with poor or moderate seed production. Squirrel density fluctuated in synchrony with the food resource, eliminating the time-lag normally present when resources are produced in pulses. In all years except 2009 (a mast-crop year), all Arolla pine cones were harvested (their seeds consumed and/or cached) by September to late October by different species. Both squirrels and nutcrackers (Nucifraga caryocatactes) fed on seeds, and their relative pre-dispersal predation rates (on cones in the canopy) differed between years. Overall, nutcrackers consumed more seeds between July and October than squirrels, but in 1 year squirrels took the largest number of seeds. Pre-dispersal seed predation by squirrels tended to be lower in years with large seed-crop size and there was a positive correlation, over the entire study period, between density of recovered hoards and Arolla pine seed density of the previous year. We conclude that (i) squirrels and nutcrackers are important pre-dispersal seed predators and seeds dispersers; (ii) squirrels are also post-dispersal seed predators, and (iii) the proportion of cached seeds consumed by squirrels increased with the size of the Arolla pine seed-crop, suggesting that red squirrel is a conditional mutualistic scatterhoarder of Arolla pine seeds. 相似文献
905.
Peter Miehle Rüdiger Grote Michael Battaglia Paul M. Feikema Stefan K. Arndt 《European Journal of Forest Research》2010,129(3):377-391
Versatile process-oriented ecosystem models are discussed as promising tools for the analyses of ecosystem services beyond
wood yield, such as catchment water yield, sequestration of carbon and greenhouse gas balances. However, long-term yield simulation
is often regarded as a weakness of such versatile models. In this context, we present a multiple response evaluation of the
modular, process-based forest growth model MoBiLE-PDT based on mensurational data from 38 permanent sample plots in commercial
Eucalyptus globulus plantations in Australia followed from establishment to 8 years of stand age. MoBiLE-PDT is based on the PnET-N-DNDC model
and considers nitrogen availability and drought stress dynamically in dependence on tree and stand properties as well as on
climate and deposition. New tree dimensions are calculated directly from carbon allocated to sapwood and mortality is derived
from stand density. Towards the end of the rotation, model efficiency E was 0.58 for stand volume (m3 ha−1) and 0.54 for aboveground biomass (t C ha−1). In a comparison with similar forest growth models evaluated against the same data only one had a better model efficiency,
whereas MoBiLE-PDT was the most versatile model for the analyses of ecosystem services. Due to its modular structure, further
model extensions for more ecological applications are easily possible. 相似文献
906.
907.
Ingo Whler Stefan Klaß Manigee Derakshani Gerold Stellmacher Jrg-Ulrich Winter Werner Reißer 《植物养料与土壤学杂志》1998,161(1):31-34
The occurrence of terrestrial algae on two beech sites was determined qualitatively and quantitatively in the litter, organic and mineral layer. Both sites are beech stands of different age and the soil type is a Cambisol. On the site with young beech the maximal value determined was 1.0 · 108 algae g?1 dw in the litter layer. With increasing soil depth the number of algae decreased on both sites, and at the young beech stand site no algae were found in the mineral soil. Chlorophyceae were the dominant algae group and at the young beech stand Bacillariophyceae were present. 相似文献
908.
The purpose of this study was to investigate how wheat cultivar, growth location, type of mill, LMW sugar composition of wheat flours, mixing time, and type of mixer affected yeast fermentation. Also studied was the effect of yeast fermentation and LMW sugar composition on hearth bread quality. To achieve this, 36 different flours were produced from two different mills using six different wheat cultivars grown at three locations. Yeast fermentation in doughs, measured as gas production, was determined using realtime pressure measurements and GasSmart software. A short mixograph mixing or spatula mixing was not efficient enough to rehydrate instant dry yeast. Compressed yeast and a short mixing time were enough to reach maximum fermentation rate. Maximum pressure after 210 min of fermentation was higher for instant dry yeast than for compressed yeast. Wheat cultivar and growth location had a significant effect on LMW sugar composition. Wheat cultivar, growth location, and type of mill used significantly affected pressure curve parameters. Oligosaccharides and damaged starch were positively correlated, and ash content and flour yield were negatively correlated with pressure curve parameters. Hearth bread characteristic crumb structure was positively correlated with all pressure curve characteristics except fast fermentation rate. Increased levels of mono‐ and disaccharides in wheat flour gave hearth breads with a more round shape. 相似文献
909.