排序方式: 共有59条查询结果,搜索用时 15 毫秒
21.
Truls Aas Halvor Solheim Robert Jankowiak Piotr Bilański Georg Hausner 《Fungal biology》2018,122(12):1142-1158
Ophiostoma spp. (Ophiostomatales, Ascomycota) are well-known fungi associated with bark and ambrosia beetles (Curculionidae: Scolytinae, Platypodinae). Fungi in the Ophiostomatales include serious tree pathogens as well as agents of timber blue-stain. Although these fungi have been extensively studied in the northern hemisphere, very little is known regarding their occurrence on hardwoods in Europe. The aims of the present study were to identify and characterize new Ophiostoma spp. associated with bark and ambrosia beetles infesting hardwoods in Norway and Poland, and to resolve phylogenetic relationships of Ophiostoma spp. related to the Norwegian and Polish isolates, using multigene phylogenetic analyses. Results obtained from five gene regions (ITS, LSU, β-tubulin, calmodulin, translation elongation factor 1-α) revealed four new Ophiostoma spp. These include Ophiostoma hylesinum sp. nov., O. signatum sp. nov., and O. villosum sp. nov. that phylogenetically are positioned within the Ophiostoma ulmi complex. The other new species, Ophiostoma pseudokarelicum sp. nov. reside along with Ophiostoma karelicum in a discrete, well-supported phylogenetic group in Ophiostoma s. stricto. The results of this study clearly show that the diversity and ecology of Ophiostoma spp. on hardwoods in Europe is poorly understood and that further studies are required to enrich our knowledge about these fungi. 相似文献
22.
In the threespine stickleback Gasterosteus aculeatus model system, phenotypes are often classified into three morphs according to lateral plate number. Morph identity has been shown to be largely genetically determined, but substantial within‐morph variation in plate number exists. In this study, we test whether plate number has a plastic component in response to salinity in the low‐plated morph using a split‐clutch experiment where families were split in two, one half raised in water at 0 and the other at 30 ppt salt. We find a small salinity‐induced plastic effect on plate number in an unexpected direction, opposite to what we predicted: Fish raised in freshwater on average have slightly more plates than fish raised in saltwater. Our results confirm that heritability of plate number is high. Additionally, we find that variance in plate number at the family level can be predicted from other family level traits, which might indicate that epistatic interactions play a role in creating the observed pattern of lateral plate number variation. 相似文献
23.
Truls Råmunddal 《Biochemical and biophysical research communications》2009,385(3):336-340
Background
The heart produces apolipoprotein-B containing lipoproteins (apoB) whose function is not well understood. The aim of this study was to evaluate importance of myocardial apoB for cardiac function, structure and survival in myocardial infarction (MI) and heart failure (HF).Methods and results
MI was induced in mice (n = 137) and myocardial apoB content was measured at 30 min, 3, 6, 24, 48, 120 h and 8 weeks post-MI. Transgenic mice overexpressing apoB (n = 27) and genetically matched controls (n = 27) were used to study the effects of myocardial apoB on cardiac function, remodeling, arrhythmias and survival after MI. Echocardiography was performed at rest and stress conditions at baseline, 2, 4 and 6 week post-MI and cumulative survival rate was registered. The myocardial apoB content increased both in the injured and the remote myocardium (p < 0.05) in response to ischemic injury. ApoB mice had 2-fold higher survival rate (p < 0.05) and better systolic function (p < 0.05) post-MI.Conclusion
Overexpression of apoB in the heart increases survival and improves cardiac function after acute MI. Myocardial apoB may be an important cardioprotective system in settings such as myocardial ischemia and HF. 相似文献24.
Bård O. Karlsen Kevin Klingan Åse Emblem Tor E. Jørgensen Alexander Jueterbock Tomasz Furmanek Galice Hoarau Steinar D. Johansen Jarle T. Nordeide Truls Moum 《Molecular ecology》2013,22(20):5098-5111
Atlantic cod displays a range of phenotypic and genotypic variations, which includes the differentiation into coastal stationary and offshore migratory types of cod that co‐occur in several parts of its distribution range and are often sympatric on the spawning grounds. Differentiation of these ecotypes may involve both historical separation and adaptation to ecologically distinct environments, the genetic basis of which is now beginning to be unravelled. Genomic analyses based on recent sequencing advances are able to document genomic divergence in more detail and may facilitate the exploration of causes and consequences of genome‐wide patterns. We examined genomic divergence between the stationary and migratory types of cod in the Northeast Atlantic, using next‐generation sequencing of pooled DNA from each of two population samples. Sequence data was mapped to the published cod genome sequence, arranged in more than 6000 scaffolds (611 Mb). We identified 25 divergent scaffolds (26 Mb) with a higher than average gene density, against a backdrop of overall moderate genomic differentiation. Previous findings of localized genomic divergence in three linkage groups were confirmed, including a large (15 Mb) genomic region, which seems to be uniquely involved in the divergence of migratory and stationary cod. The results of the pooled sequencing approach support and extend recent findings based on single‐nucleotide polymorphism markers and suggest a high degree of reproductive isolation between stationary and migratory cod in the North‐east Atlantic. 相似文献
25.
26.
Rønnestad BR Hansen EA Raastad T 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(1):158-166
The effects of strength training on freely chosen cadence and physiological responses in cyclists and recreationally active individuals were investigated. Well-trained cyclists were assigned to either usual endurance training combined with strength training (C-ES; n = 11) or usual endurance training only (C-E; n = 9). Recreationally active individuals (R-S; n = 7) performed the same strength training as C-ES did (4 lower body exercises, 3 × 4-10 repetition maximum [RM], twice a week for 12 weeks). The R-S and C-ES increased 1RM to a similar extent after 4 and 12 weeks (p < 0.01), whereas 1RM remained unchanged in C-E. Only R-S increased patellar tendon cross-sectional area (CSA; 7 ± 1%, p < 0.001). After 4 weeks, R-S reduced freely chosen cadence, oxygen consumption, heart rate, rating of perceived exertion, and blood lactate concentration during cycling at 125 W. These responses remained reduced throughout the intervention period (p < 0.05). No significant changes were observed in these physiological variables in C-ES and C-E. In conclusion, freely chosen cadence during submaximal cycling was reduced in recreationally active individuals after a period of strength training but was not reduced in well-trained cyclists. The reduced freely chosen cadence may be associated with the observed increase in patellar tendon CSA through a morphological-sensory-motor interaction. A practical application is that heavy strength training can reduce freely chosen cadence during submaximal cycling and thereby improve cycling economy in recreationally active individuals, whereas other mechanisms should account for improved performance after strength training in well-trained cyclists. 相似文献
27.
Sonja Windhager Fred L. Bookstein Karl Grammer Elisabeth Oberzaucher Hasen Said Dennis E. Slice Truls Thorstensen Katrin Schaefer 《Evolution and human behavior》2012,33(2):109-120
It was recently shown that Austrians associate car front geometry with traits in a way that could be related to face shape geometry mapping to those same overall suites of traits. Yet, possible confounding effects of familiarity with the car models, media coverage and entertainment could not be ruled out. In order to address this, the current study uses a cross-cultural comparison. Adult subjects in two countries (Austria and Ethiopia, n=129) were asked to rate person characteristics of 46 standardized front views of automobiles on various trait scales. These two countries differ substantially with regard to their experience with car models and brands, as well as car marketing and media coverage. Geometric morphometrics was then used to assess the shape information underlying trait attribution. Car shapes for perceived maturity, maleness and dominance were highly similar in both countries, with patterns comparable to shape changes during facial growth in humans: Relative sizes of the forehead and windshield decrease with age/growth, eyes and headlights both become more slit-like, noses and grilles bigger, lips and air-intakes are wider. Austrian participants further attributed various degrees of some interpersonal attitudes and emotions, whereas neither Austrians nor Ethiopians congruently ascribed personalities. Morphological correlates of personal characteristics are discussed, as are person perception and its overgeneralization to inanimate objects. Cross-cultural similarities and differences are addressed, as well as implications for car styling, follow-up studies on driving and pedestrian behavior, and fundamental dimensions in inference from (human) faces. 相似文献
28.
Paulsen G Vissing K Kalhovde JM Ugelstad I Bayer ML Kadi F Schjerling P Hallén J Raastad T 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,293(2):R844-R853
In this study the stress protein response to unaccustomed maximal eccentric exercise in humans was investigated. Eleven healthy males performed 300 maximal eccentric actions with the quadriceps muscle. Biopsies from vastus lateralis were collected at 30 min and 4, 8, 24, 96, and 168 h after exercise. Cellular regulation and localization of heat shock protein (HSP) 27, alpha B-crystallin, and HSP70 were analyzed by immunohistochemistry, ELISA technique, and Western blotting. Additionally, mRNA levels of HSP27, alpha B-crystallin, and HSP70 were quantified by Northern blotting. After exercise (30 min), 81 +/- 8% of the myofibers showed strong HSP27 staining (P < 0.01) that gradually decreased during the following week. alpha B-Crystallin mimicked the changes observed in HSP27. After exercise (30 min), the ELISA analysis showed a 49 +/- 13% reduction of the HSP27 level in the cytosolic fraction (P < 0.01), whereas Western blotting revealed a 15-fold increase of the HSP27 level in the myofibrillar fraction (P < 0.01). The cytosolic HSP70 level increased to 203 +/- 37% of the control level 24 h after exercise (P < 0.05). After 4 days, myofibrillar-bound HSP70 had increased approximately 10-fold (P < 0.01) and was accompanied by strong staining on cross sections. mRNA levels of HSP27, alpha B-crystallin, and HSP70 were all elevated the first day after exercise (P < 0.01); HSP70 mRNA showed the largest increase (20-fold at 8 h). HSP27 and alpha B-crystallin seemed to respond immediately to maximal eccentric exercise by binding to cytoskeletal/myofibrillar proteins, probably to function as stabilizers of disrupted myofibrillar structures. Later, mRNA and total HSP protein levels, especially HSP70, increased, indicating that HSPs play a role in skeletal muscle recovery and remodeling/adaptation processes to high-force exercise. 相似文献
29.
30.
RNA deep sequencing of the Atlantic cod transcriptome 总被引:1,自引:0,他引:1
Steinar D. Johansen Brd Ove Karlsen Tomasz Furmanek Morten Andreassen Tor Erik Jrgensen Teshome T. Bizuayehu Ragna Breines se Emblem Pivi Kettunen Keijo Luukko Rolf B. Edvardsen Jarle T. Nordeide Dag H. Coucheron Truls Moum 《Comparative biochemistry and physiology. Part D, Genomics & proteomics》2011,6(1):18-22