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151.
E. Fuglei N. A. Øritsland 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1999,169(6):361-369
Post-absorptive resting metabolic rates (RMRs), body mass and ad libitum food intake were recorded on an annual cycle in
captive arctic foxes (Alopex lagopus) at Svalbard. During the light season in May and in the dark period in November, RMR during starvation and subsequent re-feeding
were also measured. In contrast to earlier findings, the present study indicated a seasonal trend in post-absorptive RMR (in
W · kg−1 and W · kg−0.75). The values in the light summer were 15% and 11% higher than the values in the dark winter, suggesting a physiological adaptation
aiding energy conservation during winter in arctic foxes. Body mass and ad libitum food intake varied inversely through the
year. A significant reduction in RMR (in W and W · kg−0.75) with starvation (metabolic depression) was recorded both in May and November, indicating an adaptation to starvation in
arctic foxes. The lack of metabolic depression during a period of starvation that was concomitant with extremely cold ambient
temperatures in November 1994 indicates that metabolic responses to starvation may be masked by thermoregulatory needs. At
very low ambient temperatures, arctic foxes may require increased heat production which cannot be achieved via below-average
rates of metabolism.
Accepted: 7 June 1999 相似文献
152.
Maria B. Olsen Gunn A. Hildrestrand Katja Scheffler Leif Erik Vinge Katrine Alfsnes Vuk Palibrk Junbai Wang Christine G. Neurauter Luisa Luna Jostein Johansen Jonas D.S. Øgaard Ingrid K. Ohm Geir Slupphaug Anna Kuśnierczyk Arnt E. Fiane Sverre-Henning Brorson Lili Zhang Lars Gullestad Alexandra V. Finsen 《Cell reports》2017,18(1):82-92
153.
Døhn UM Ejbjerg BJ Hasselquist M Narvestad E Møller J Thomsen HS Østergaard M 《Arthritis research & therapy》2008,10(1):R25-8
Background
The objectives of the present study were, with multidetector computed tomography (CT) as the reference method, to determine the performance of magnetic resonance imaging (MRI) and radiography for the detection of bone erosions in rheumatoid arthritis wrist bones, and to test whether measuring volumes of erosions on CT and MRI is reproducible and correlated to semiquantitative assessments (scores) of erosions on CT, MRI and radiography.Methods
Seventeen patients with rheumatoid arthritis and four healthy control individuals underwent CT, MRI and radiography of one wrist, performed on the same day. CT was performed on a Philips Mx8000IDT unit (voxel size 0.4 mm × 0.4 mm × 1 mm) and MRI was performed on a Philips Panorama 0.6T unit (voxel size 0.4 mm × 0.4 mm × 0.4 mm). Images were evaluated separately for erosions in all wrist bones and were scored according to the principles of the Outcome Measures in Rheumatology Rheumatoid Arthritis MRI Scoring System (CT and MRI) and the Sharp/van der Heijde (radiographs) scoring methods. Measurements of erosion volumes of all erosions were performed twice with a 1-week interval.Results
With CT as the reference method, the overall sensitivity, specificity and accuracy (concordance) of MRI for detecting erosions were 61%, 93% and 77%, respectively, while the respective values were 24%, 99% and 63% for radiography. The intramodality agreements when measuring erosion volumes were high for both CT and MRI (Spearman correlation coefficients 0.92 and 0.90 (both P < 0.01), respectively). Correlations between volumes and scores of individual erosions were 0.96 for CT and 0.99 for MRI, while they were 0.83 (CT) and 0.80 (MRI) for persons' total erosion volume and total score (all P < 0.01).Conclusion
With CT as the reference method, MRI showed moderate sensitivity and good specificity and accuracy for detection of erosions in rheumatoid arthritis and healthy wrist bones, while radiography showed very low sensitivity. The tested volumetric method was highly reproducible and correlated to scores of erosions. 相似文献154.
155.
Karen Helene Ørstavik 《Human genetics》2009,126(3):363-373
156.
157.
Christine Finnie Merethe Bagge Torben Steenholdt Ole Østergaard Kristian Sass Bak-Jensen Gunter Backes Anaïs Jensen Henriette Giese Jørgen Larsen Peter Roepstorff Birte Svensson 《Functional & integrative genomics》2009,9(1):135-143
Two-dimensional gel electrophoresis was used to screen spring barley cultivars for differences in seed protein profiles. In
parallel, 72 microsatellite (simple sequence repeat (SSR)) markers and 11 malting quality parameters were analysed for each
cultivar. Over 60 protein spots displayed cultivar variation, including peroxidases, serpins and proteins with unknown functions.
Cultivars were clustered based on the spot variation matrix. Cultivars with superior malting quality grouped together, indicating
malting quality to be more closely correlated with seed proteomes than with SSR profiles. Mass spectrometry showed that some
spot variations were caused by amino acid differences encoded by single nucleotide polymorphisms (SNPs). Coding SNPs were
validated by mass spectrometry, expressed sequence tag and 2D gel data. Coding SNPs can alter function of affected proteins
and may thus represent a link between cultivar traits, proteome and genome. Proteome analysis of doubled haploid lines derived
from a cross between a malting (Scarlett) and a feed cultivar (Meltan) enabled genetic localisation of protein phenotypes
represented by 48 spot variations, involving e.g. peroxidases, serpins, α-amylase/trypsin inhibitors, peroxiredoxin and a
small heat shock protein, in relation to markers on the chromosome map.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
158.
The availability and utility of genome‐scale metabolic reconstructions have exploded since the first genome‐scale reconstruction was published a decade ago. Reconstructions have now been built for a wide variety of organisms, and have been used toward five major ends: (1) contextualization of high‐throughput data, (2) guidance of metabolic engineering, (3) directing hypothesis‐driven discovery, (4) interrogation of multi‐species relationships, and (5) network property discovery. In this review, we examine the many uses and future directions of genome‐scale metabolic reconstructions, and we highlight trends and opportunities in the field that will make the greatest impact on many fields of biology. 相似文献
159.
The secreted morphogens of the Hedgehog family have important roles in normal development as well as in associated pathologies, including cancer. The Hedgehog signalling pathway has been studied in Drosophila and is thought to be conserved in vertebrates. Hedgehog elicits a signalling response that activates Smoothened (Smo). There is evidence of differences between Drosophila and vertebrates concerning signalling downstream of Smo, as well as in Smo itself. Here, we discuss this evidence and its importance for investigations of the pathway and related biology, as well as for the development of drugs targeting components of the pathway for treatment of associated pathologies. 相似文献
160.
Dres Damgaard Mads Emil Bjørn Peter Østrup Jensen Claus Henrik Nielsen 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):1203-1208
Protein citrullination catalysed by peptidylarginine deiminase (PAD) may play an important pathogenic role in several chronic inflammatory diseases and malignancies. PAD2, PAD4, and citrullinated proteins are found in the synovium of rheumatoid arthritis patients. PAD activity is dependent on calcium and reducing conditions. However, reactive oxygen species (ROS) have been shown to induce citrullination of histones in granulocytes. Here we examine the ability of H2O2 and leukocyte-derived ROS to regulate PAD activity using citrullination of fibrinogen as read-out. H2O2 at concentrations above 40?µM inhibited the catalytic activity of PAD2 and PAD4 in a dose-dependent manner. PMA-stimulated leukocytes citrullinated fibrinogen and this citrullination was markedly enhanced when ROS formation was inhibited by the NADPH oxidase inhibitor diphenyleneiodonium (DPI). In contrast, PAD released from stimulated leukocytes was unaffected by exogenously added H2O2 at concentrations up to 1000?µM. The role of ROS in regulating PAD activity may play an important part in preventing hypercitrullination of proteins. 相似文献