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61.
Christina Gabrielsen Dag A. Brede Pablo E. Hernández Ingolf F. Nes Dzung B. Diep 《Journal of bacteriology》2012,194(24):6976-6977
This work describes the draft genome sequence of Lactococcus garvieae DCC43. The 2.2-Mb draft genome contains 2,227 predicted protein-coding genes, among which is a region encoding the bacteriocin garvicin ML. No antibiotic resistance genes or capsule-related virulence genes were identified. Two plasmid replication regions indicate that this strain likely contains plasmids. Comparative genomics suggests that this strain displays a high degree of sequence variation from the previously sequenced L. garvieae strains. 相似文献
62.
Hidalgo M Gusdal Y Dingsør GE Hjermann D Ottersen G Stige LC Melsom A Stenseth NC 《Proceedings. Biological sciences / The Royal Society》2012,279(1727):275-283
Biological processes and physical oceanography are often integrated in numerical modelling of marine fish larvae, but rarely in statistical analyses of spatio-temporal observation data. Here, we examine the relative contribution of inter-annual variability in spawner distribution, advection by ocean currents, hydrography and climate in modifying observed distribution patterns of cod larvae in the Lofoten-Barents Sea. By integrating predictions from a particle-tracking model into a spatially explicit statistical analysis, the effects of advection and the timing and locations of spawning are accounted for. The analysis also includes other environmental factors: temperature, salinity, a convergence index and a climate threshold determined by the North Atlantic Oscillation (NAO). We found that the spatial pattern of larvae changed over the two climate periods, being more upstream in low NAO years. We also demonstrate that spawning distribution and ocean circulation are the main factors shaping this distribution, while temperature effects are different between climate periods, probably due to a different spatial overlap of the fish larvae and their prey, and the consequent effect on the spatial pattern of larval survival. Our new methodological approach combines numerical and statistical modelling to draw robust inferences from observed distributions and will be of general interest for studies of many marine fish species. 相似文献
63.
ABSTRACT: BACKGROUND: Progressive neurodegeneration in Alzheimer's disease (AD) induces cognitive deterioration, and there is controversy regarding the optimal treatment strategy in early AD. Stimulation therapy, including physical exercise and cholinesterase inhibitors are both reported to postpone cognitive deterioration in separate studies. We aimed to study the effect of stimulation therapy and the additional effect of donepezil on cognitive function in early AD. METHOD: DESIGN: A two-by-two factorial trial comprising stimulation therapy for one year compared to standard care to which a randomized double-blinded placebo controlled trial with donepezil was added. SETTING: Nine rural municipalities in Northern Norway. PARTICIPANTS: 187 participants [greater than or equal to]65 years with a recent diagnosis of mild or moderate AD were included in the study of which 146 completed a one-year follow-up. INTERVENTIONS: In five municipalities the participants received stimulation therapy whereas participants in four received standard care. All participants were randomised double-blinded to donepezil or placebo and tested with three different cognitive tests four times during the one-year study period. MAIN OUTCOME: Changes in MMSE sum score. SECONDARY OUTCOME: Changes in ADAS-Cog and Clock Drawing Test. RESULTS: MMSE scores remained unchanged amongst AD participants receiving stimulation therapy and those receiving standard care. The results were consistent for ADAS-Cog and Clock Drawing Test. No time trend differences were found during one-year follow-up between groups receiving stimulation therapy versus standard care or between donepezil versus placebo. CONCLUSION: In rural AD patients non-pharmacological and pharmacological therapy did not improve outcome compared with standard care but all groups retained cognitive function during one year follow-up. Other studies are needed to confirm these results. ClinicalTrials.gov (Identifier: NCT00443014). EudraCT database (no 2004-002613-37). KEYWORDS: Alzheimer's disease. Symptomatic treatment. Postponement of cognitive deterioration. 相似文献
64.
Thorsten Kleinjung Joppe W. Bos Arjen K. Lenstra Dag Arne Osvik Kazumaro Aoki Scott Contini Jens Franke Emmanuel Thomé Pascal Jermini Michela Thiémard Paul Leyland Peter L. Montgomery Andrey Timofeev Heinz Stockinger 《Cluster computing》2012,15(1):53-68
In December 2009 the 768-bit, 232-digit number RSA-768 was factored using the number field sieve. Overall, the computational challenge would take more than 1700 years on a single, standard core. In the article we present the heterogeneous computing approach, involving different compute clusters and Grid computing environments, used to solve this problem. 相似文献
65.
66.
Dag Klaveness 《Limnology》2005,6(2):131-136
During a survey of Norwegian lakes, photographic records were made of lake color as reflected by a white Secchi disk positioned at half of the depth of extinction. The pictorial distinction between different lakes is documented in this article. The pictures recorded can readily be transferred to a color model [e.g., Commission Internationale de L’Éclairage (CIE)-Lab]; from there, numerical color parameter values such as hue (h*, the quality of color) and chroma (C*, the intensity of color) may be assigned to each record. There are, however, limitations and obstacles connected with the transformation of color values recorded by a CCD camera (or film digitizers) to absolute numerical values comparable between different cameras and systems. A single CCD camera may be useful for documenting lake color, but there are technical limitations restricting its use as a scientific instrument for quantitative purposes. 相似文献
67.
Molecular and Genetic Characterization of Propionicin F, a Bacteriocin from Propionibacterium freudenreichii
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Dag Anders Brede Therese Faye Ola Johnsborg Inger
degrd Ingolf F. Nes Helge Holo 《Applied microbiology》2004,70(12):7303-7310
This work describes the purification and characterization of propionicin F, the first bacteriocin isolated from Propionibacterium freudenreichii. The bacteriocin has a bactericidal activity and is only active against strains of P. freudenreichii. Propionicin F appears to be formed through a processing pathway new to bacteriocins. The mass of the purified bacteriocin was determined by mass spectrometry, and the N-terminal amino acid sequence was determined by Edman degradation. Sequencing of pcfA, the bacteriocin structural gene, revealed that propionicin F corresponds to a 43-amino-acid peptide in the central part of a 255-amino-acid open reading frame, suggesting that mature propionicin F is excised from the probacteriocin by N- and C-terminal proteolytic modifications. DNA sequencing and Northern blot hybridizations revealed that pcfA is cotranscribed with genes encoding a putative proline peptidase and a protein from the radical S-adenosylmethionine family. A gene encoding an ABC transporter was also identified in close proximity to the bacteriocin structural gene. The potential role of these genes in propionicin F maturation and secretion is discussed. 相似文献
68.
69.
In normal gravity, lung diffusing capacity (DL(CO)) and lung tissue volume (LTV; including pulmonary capillary blood volume) change in concert, for example, during shifts between upright and supine. Accordingly, DL(CO) and LTV might be expected to decrease together in sitting subjects in hypergravity due to peripheral pooling of blood and reduced central blood volume. Nine sitting subjects in a human centrifuge were exposed to one, two, and three times increased gravity in the head-to-feet direction (G(z+)) and rebreathed a gas containing trace amounts of acetylene and carbon monoxide. DL(CO) was 25.2 +/- 2.6, 20.0 +/- 2.1, and 16.7 +/- 1.7 ml. min(-1). mbar(-1) (means +/- SE) at 1, 2, and 3 G(z+), respectively (ANOVA P < 0.001). Corresponding values for LTV increased from 541 +/- 34 to 677 +/- 43, and 756 +/- 71 ml (P < 0.001) at 2 and 3 G(z+). Results are compatible with sequestration of blood in the dependent part of the pulmonary circulation just as in the systemic counterpart. DL(CO,) which under normoxic conditions is mainly determined by its membrane component, decreased despite an increased pulmonary capillary blood volume, most likely as a consequence of a less homogenous distribution of alveolar volume with respect to pulmonary capillary blood volume. 相似文献
70.
Jan Aaseth Yngvar Thomassen Dag Gunnar Ellingsen Grethe Sta-Birketvedt 《Journal of trace elements in medicine and biology》2001,15(2-3):167-174
In the present study 67 non-anaemic women were randomly allocated to either 100 mg or 15 mg iron daily at about the 10. week of pregnancy. At about week 18, 30 and 36 of pregnancy, as well as 6 weeks after delivery, hemoglobin and the serum concentrations of ferritin, vitamin B12, folates, Zn, Cu and Se were monitored. Dietary allowances of other minerals and vitamins are also increased in pregnancy, and the 15 mg iron tablet was enriched with Zn (10 mg), Cu (2 mg), Se (50 microg), vitamin B12 (3 microg), and folate (0.1 mg). Neither ferritin, nor Cu, Zn or Se concentrations differed statistically significantly between the treatment groups during pregnancy. Ferritin and Zn appeared to decrease approximately parallel to the hemodilution, whereas Cu concentrations increased from a non-pregnant reference mean of 18 micromol Cu/L to a maximum mean of nearly 33 micromol Cu/L during pregnancy. Se decreased concomitantly to about 1.0 micromol Se/L. Serum folate (around 15 micromol/L) was essentially unaffected by pregnancy in the group given multivitamin/mineral supplementation, whereas the mean concentration fell below 10 micromol/L in the group supplemented with 100 mg iron daily. Our results indicate that supplementation of 15 mg Fe daily during pregnancy results in a small reduction of hemoglobin. It is suggested that additional supplementation with folate might be of importance to maintain the serum folate concentration during pregnancy. 相似文献