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981.
An automatic method using dyed cellulose as a substrate was developed to determine the solubilizing activity of a cellulase complex. The automatic analyzer was connected to a fermentor and enzyme activity was successfully assayed during fermentation. A useful sampling arrangement was developed and the analysis was sensitive enough to make a short reaction time possible. Cellulase production with Trichoderma viride was used as a model process. 相似文献
982.
983.
Maarit Hallikainen Essi Sarkkinen Ingmar Wester Matti Uusitupa 《BMC cardiovascular disorders》2002,2(1):14-7
Background
The short-term cholesterol-lowering efficacy of plant stanol esters has been open to debate, and the data from different clinical studies with hypercholesterolemic subjects are variable, partly due to lack of systematic studies. Therefore, we investigated the time in days needed to obtain the full cholesterol-lowering effect of stanol esters in hypercholesterolemic subjects. 相似文献984.
Leif Schulman Kalle Ruokolainen Leo Junikka Ilari E. Sääksjärvi Matti Salo Sanna-Kaisa Juvonen Jukka Salo Mark Higgins 《Biodiversity and Conservation》2007,16(11):3011-3051
Protected areas are crucial for Amazonian nature conservation. Many Amazonian reserves have been selected systematically to
achieve biodiversity representativeness. We review the role natural-scientific understanding has played in reserve selection,
and evaluate the theoretical potential of the existing reserves to cover a complete sample of the species diversity of the
Amazonian rainforest biome. In total, 108 reserves (604,832 km2) are treated as strictly protected and Amazonian; 87 of these can be seen as systematically selected to sample species diversity
(75.3% of total area). Because direct knowledge on all species distributions is unavailable, surrogates have been used to
select reserves: direct information on some species distributions (15 reserves, 14.8% of total area); species distribution
patterns predicted on the basis of conceptual models, mainly the Pleistocene refuge hypothesis, (5/10.3%); environmental units
(46/27.3%); or a combination of distribution patterns and environmental units (21/22.9%). None of these surrogates are reliable:
direct information on species distributions is inadequate; the Pleistocene refuge hypothesis is highly controversial; and
environmental classifications do not capture all relevant ecological variation, and their relevance for species distribution
patterns is undocumented. Hence, Amazonian reserves cannot be safely assumed to capture all Amazonian species. To improve
the situation, transparency and an active dialogue with the scientific community should be integral to conservation planning.
We suggest that the best currently available approach for sampling Amazonian species diversity in reserve selection is to
simultaneously inventory indicator plant species and climatic and geological conditions, and to combine field studies with
remote sensing. 相似文献
985.
Kati Pasanen Jari Parkkari Matti Pasanen Hannele Hiilloskorpi Tanja M?kinen Markku J?rvinen Pekka Kannus 《BMJ (Clinical research ed.)》2008,337(7661):96-99
Objective To investigate whether a neuromuscular training programme is effective in preventing non-contact leg injuries in female floorball players.Design Cluster randomised controlled study.Setting 28 top level female floorball teams in Finland.Participants 457 players (mean age 24 years)—256 (14 teams) in the intervention group and 201 (14 teams) in the control group—followedup for one league season (six months).Intervention A neuromuscular training programme to enhance players’ motor skills and body control, as well as to activate and prepare their neuromuscular system for sports specific manoeuvres.Main outcome measure Acute non-contact injuries of the legs.Results During the season, 72 acute non-contact leg injuries occurred, 20 in the intervention group and 52 in the control group. The injury incidence per 1000 hours playing and practise in the intervention group was 0.65 (95% confidence interval 0.37 to 1.13) and in the control group was 2.08 (1.58 to 2.72). The risk of non-contact leg injury was 66% lower (adjusted incidence rate ratio 0.34, 95% confidence interval 0.20 to 0.57) in the intervention group.Conclusion A neuromuscular training programme was effective in preventing acute non-contact injuries of the legs in female floorball players. Neuromuscular training can be recommended in the weekly training of these athletes.Trial registration Current Controlled Trials ISRCTN26550281. 相似文献
986.
Oxygen Radical Injury and Loss of High-Energy Compounds in Anoxic and Reperfused Rat Heart: Prevention By Exogenous Fructose-1, 6-Bisphosphate 总被引:5,自引:0,他引:5
Barbara Tavazzi Loredana Cerroni Donato Di Pierro Giuseppe Lazzarino Matti Nuutinen Joseph W. Starnes Bruno Giardina 《Free radical research》1990,10(3):167-176
Isolated Langendorff-perfused rat hearts after 10 minutes preperfusion, were subjected to a substrate-free anoxic perfusion (20 minutes) followed by 20 minutes reperfusion with a glucose-containing oxygen-balanced medium. Under the same perfusion conditions, the effect of exogenous 5mM fructose-1, 6-bisphosphate has been investigated. The xanthine dehydrogenase to xanthine oxidase ratio, concentrations of high-energy phosphates and the TBA-reactive material (TBARS) were determined at the end of each perfusion period in both control and fructose-1, 6-bisphosphate-treated hearts. Results indicate that anoxia induces the irreversible transformation of xanthine dehydrogenase into oxidase as a consequence of the sharp decrease of the myocardial energy metabolism. This finding is supported by the protective effect exerted by exogenous fructose-1, 6-bisphosphate which is able to maintain the correct xanthine dehydrogenase/oxidase ratio by preventing the depletion of phosphorylated compounds during anoxia. Moreover, in control hearts, the release oflactate dehydrogenase during reperfusion, is paralleled by a 50% increase in the concentration of tissue TBARS. On the contrary, in fructose-1, 6-bisphosphate-treated hearts this concentration does not significantly change after reoxygenation, while a slight but significant increase of lactate dehydrogenase activity in the perfusates is observed.
On the whole these data indicate a direct contribution of oxygen-derived free radicals to the worsening of post-anoxic hearts. A hypothesis on the mechanism of action of fructose-1, 6-bisphosphate in anoxic and reperfused rat heart and its possible application in the clinical therapy of myocardial infarction are presented. 相似文献
On the whole these data indicate a direct contribution of oxygen-derived free radicals to the worsening of post-anoxic hearts. A hypothesis on the mechanism of action of fructose-1, 6-bisphosphate in anoxic and reperfused rat heart and its possible application in the clinical therapy of myocardial infarction are presented. 相似文献
987.
Demographic costs of Chaoborus-induced defences in Daphnia pulex: a sensitivity analysis 总被引:2,自引:0,他引:2
Summary We examined the demographic costs of Chaoborus-induced defensive spine structures in Daphnia pulex. Our aim was to assess the role of resource limitation and the interaction effects of limiting food level and antipredator structures on fitness of D. pulex and to pinpoint those life stages that are most sensitive to changes in the defence regime. Chaoborus-induced and typical morphotypes of D. pulex were reared at high and low food concentrations. Instar-based matrix population models were used to quantify the effects of predator-induction, food and their interaction on fitness of D. pulex. Predator-induction caused a statistically significant reduction in fitness at low food levels, but not at high food levels. Sensitivity analyses revealed that the fitness effects were primarily due to changes in the growth rate in instars 1–5, and secondarily to small reductions in the fertility of instars 5–10. The interaction between Chaoborus exposure and low food concentration was negative, and mediated through growth and fertility components. Both these components were reduced more in the Chaoborus-exposed, low food treatment than would be expected in the absence of interaction. 相似文献