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排序方式: 共有186条查询结果,搜索用时 15 毫秒
41.
Hans-Peter Hanssen 《Phytochemistry》1985,24(6):1293-1294
Several sesquiterpene alcohols, mainly possessing a 4,10-dimethyl-7-isopropyldecaline skeleton (cadinols, muurolols, cubenols), have been identified from synthetic liquid cultures of the brown rot fungus Lentinus lepideus. Besides these, trans,trans-farnesol and the bicyclofarnesol drimenol have been found. 相似文献
42.
Until the 1970’s, Trichinella spiralis (Owen 1835) was considered the only species within the genus Trichinella. Then T. pseudospiralis (Garkavi 1972) was classified as a separate species on the basis of morphological and biological features. The remaining morphologically homogenous “T. spiralis-group” has been split into 4 different species (or subspecies) on the basis of their biological and biochemical characteristics; T. nativa (Britov & Boev 1972), T. nelsoni (Britov & Boev 1972), T. spiralis sensu stricto and T. britovi (Pozio et al. 1992). 相似文献
43.
Sebastian Clauss Reza Wakili Bianca Hildebrand Stefan K??b Eva Hoster Ina Klier Eimo Martens Alan Hanley Henner Hanssen Martin Halle Thomas Nickel 《PloS one》2016,11(2)
Introduction
Physical activity is beneficial for individual health, but endurance sport is associated with the development of arrhythmias like atrial fibrillation. The underlying mechanisms leading to this increased risk are still not fully understood. MicroRNAs are important mediators of proarrhythmogenic remodeling and have potential value as biomarkers in cardiovascular diseases. Therefore, the objective of our study was to determine the value of circulating microRNAs as potential biomarkers for atrial remodeling in marathon runners (miRathon study).Methods
30 marathon runners were recruited into our study and were divided into two age-matched groups depending on the training status: elite (ER, ≥55 km/week, n = 15) and non-elite runners (NER, ≤40 km/week, n = 15). All runners participated in a 10 week training program before the marathon. MiRNA plasma levels were measured at 4 time points: at baseline (V1), after a 10 week training period (V2), immediately after the marathon (V3) and 24h later (V4). Additionally, we obtained clinical data including serum chemistry and echocardiography at each time point.Results
MiRNA plasma levels were similar in both groups over time with more pronounced changes in ER. After the marathon miR-30a plasma levels increased significantly in both groups. MiR-1 and miR-133a plasma levels also increased but showed significant changes in ER only. 24h after the marathon plasma levels returned to baseline. MiR-26a decreased significantly after the marathon in elite runners only and miR-29b showed a non-significant decrease over time in both groups. In ER miRNA plasma levels showed a significant correlation with LA diameter, in NER miRNA plasma levels did not correlate with echocardiographic parameters.Conclusion
MiRNAs were differentially expressed in the plasma of marathon runners with more pronounced changes in ER. Plasma levels in ER correlate with left atrial diameter suggesting that circulating miRNAs could potentially serve as biomarkers of atrial remodeling in athletes. 相似文献44.
Distribution of alpha-1-antitrypsin and haptoglobin phenotypes in bladder cancer patients 总被引:2,自引:0,他引:2
Frequencies of the alpha 1-antitrypsin (Pi) alleles and haptoglobin phenotypes have been determined in a series of 264 North-German patients with bladder cancer. Compared to a healthy control population, we found a statistically significant decrease of Hp 2-2 phenotype in the patient series. A significant increase of the serum Pi Z allele, as previously shown for patient groups with certain other tumours, could also be confirmed for bladder cancer. Furthermore, a distinct association between a lowered M 3 allele and bladder carcinoma was observed. 相似文献
45.
Abstract. The effects of different kinds of data manipulation on gradient length estimation by non-linear rescal-ing (as in DCA ordination) are evaluated by considering the first axis inDCA ordinations of 11 field data sets from four investigations. Gradient length estimates are dependent on the range of the abundance scale; the more the scale favours the quantitative aspect (abundance) of the data over the qualitative aspect (presence), the longer the DCA axes. The gradient length estimate decreases when infrequent species are deleted. A new formula is proposed to replace the option for downweighting of rare species in DCA, as the option presently available has some undesirable properties. Some implications for interpretation of gradient length estimates by non-linear rescaling in general (and in DCA in particular) and for comparison of gradient length estimates between studies, are discussed. The potential of non-linear rescaling of gradients for estimation of β diversity is emphasized. 相似文献
46.
Ole J. Hanssen 《The International Journal of Life Cycle Assessment》1999,4(5):262-262
The status of Life Cycle Assessment (LCA) activities in the Nordic Region (period 1995-97) is presented, based on more than 350 reported studies from industrial companies and research institutes in Sweden, Denmark, Norway, and Finland. A large number of industrial sectors is represented, with car components, building materials, pulp and paper products, electronic components and packaging as the most important ones. All aspects of LCA methodology are used: 90% use impact assessment, 80% impact assessment and valuation step. In most studies, more than one valuation method is used for ranking environmental impacts. LCA studies are well integrated in the business activities in many large Nordic corporations. From the early attempts, more familiar with LCA methodology, LCA has been integrated in strategy development, product development, process development and, to some extent, marketing. LCA has not only been used in the strict sense presented in the ISO 14040-43 standards. The systems approach, which is the basis for LCA, has also been modified and used in Sustainable Product Development, and in Environmental Performance Indicator and Product Declarations development. Future applications should be within Environmental Impact Assessments. 相似文献
47.
Ole J. Hanssen 《The International Journal of Life Cycle Assessment》1999,4(6):315-320
The status of Life Cycle Assessment (LCA) activities in the Nordic Region (period 1995-97) is presented, based on more than
350 reported studies from industrial companies and research institutes in Sweden, Denmark, Norway, and Finland. A large number
of industrial sectors is represented, with car components, building materials, pulp and paper products, electronic components
and packaging as the most important ones. All aspects of LCA methodology are used: 90% use impact assessment, 80% impact assessment
and valuation step. In most studies, more than one valuation method is used for ranking environmental impacts.
LCA studies are well integrated in the business activities in many large Nordic corporations. From the early attempts, more
familiar with LCA methodology, LCA has been integrated in strategy development, product development, process development and,
to some extent, marketing. LCA has not only been used in the strict sense presented in the ISO 14040-43 standards. The systems
approach, which is the basis for LCA, has also been modified and used in Sustainable Product Development, and in Environmental
Performance Indicator and Product Declarations development. Future applications should be within Environmental Impact Assessments. 相似文献
48.
49.
Bustnes JO Erikstad KE Hanssen SA Tveraa T Folstad I Skaare JU 《Proceedings. Biological sciences / The Royal Society》2006,273(1605):3117-3122
Recent studies have shown that the detrimental effects of anthropogenic pollutants may be worse if organisms are exposed to natural stress. In this study, we examined whether negative effects of organochlorines (OCs) could be influenced by parasites. In two breeding seasons, we administered an anti-helminthic drug to groups of breeding glaucous gulls (Larus hyperboreus), whereas control groups were placebo treated. In all birds, blood residues of the most important OCs in the study population (hexachlorobenzene, oxychlordane, p,p'-dichlorodiphenyldichloroethylene and polychlorinated biphenyl), were measured. The relationships between OCs and fitness components (i.e. nesting success and return rate between breeding seasons) were then compared between the birds receiving anti-parasite treatment and the controls. Among untreated males, higher blood residues of OCs were associated with lowered nesting success, while in males receiving anti-parasite treatment, there was no detrimental effect of OCs on fitness. Return rate was not affected by treatment or OCs. Our findings suggest that parasites may be an important factor in triggering reproductive effects of such pollutants, and that relatively low levels of OCs may have serious reproductive consequences in natural populations when stress from other sources is high. 相似文献
50.
Eric Hanssen Nectarios Klonis Joe DeRisi 《International journal for parasitology》2010,40(1):123-1286
During its intra-erythrocytic development Plasmodium falciparum establishes a membrane network beyond its own limiting membrane in the cytoplasm of its host. These membrane structures play an important role in the trafficking of virulence proteins to the erythrocyte surface, however their ultrastructure is only partly defined and there is on-going debate regarding their origin, organisation and connectivity. We have used two whole cell imaging modalities to explore the topography of parasitised erythrocytes. Three-dimensional structured illumination microscopy provides resolution beyond the optical diffraction limit and permits analysis of fluorescently labelled whole cells. Immunoelectron tomography offers the possibility of high resolution imaging of individual ultrastructural features in a cellular context. Combined with serial sectioning and immunogold labelling, this technique permits precise mapping of whole cell architecture. We show that the P. falciparum exported secretory system comprises a series of modular units, comprising flattened cisternae, known as Maurer’s clefts, tubular connecting elements, two different vesicle populations and electron-dense structures that have fused with the erythrocyte membrane. The membrane network is not continuous, pointing to an important role for vesicle-mediated transport in the delivery of cargo to different destinations in the host cell. 相似文献