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791.
792.
Michael A. Castellini Judith M. Castellini Patricia M. Rivera 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2001,129(4):118-757
Marine mammals are known to dive up to 2000 m and, therefore, tolerate as much as 200 atm. of hydrostatic pressure. To examine possible metabolic adaptations to these elevated pressures, fresh blood samples from marine and terrestrial mammals were incubated for 2 h at 37 degrees C under 136 atm (2000 psi) of hydrostatic pressure. The consumption of plasma glucose and the production of lactate over the 2-h period were used to assess glycolytic flux in the red cells. The results indicate that glycolytic flux as measured by lactate production under pressure can be significantly depressed in most terrestrial mammals and either not altered or accelerated in marine mammals. The data also suggest that there is a significant shift in the ratio of lactate produced to glucose consumed under pressure. Interestingly, human and dolphin blood do not react to pressure. These combined data imply a metabolic adaptation to pressure in marine mammal RBC that may not be necessary in human or dolphin cells due to their unique patterns of glucose metabolism. 相似文献
793.
The brefeldin A resistance protein
Bfr1p is a component of polyribosome-associated mRNP complexes in
yeast 总被引:8,自引:6,他引:2
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Brian D. Lang Ai-min Li Heather D. Black-Brewster Judith L. Fridovich-Keil 《Nucleic acids research》2001,29(12):2567-2574
The yeast gene BFR1 was originally isolated from a genetic screen for high-copy suppressors of brefeldin A-induced lethality in Saccharomyces cerevisiae. While this result suggested a possible role for the encoded protein, Bfr1p, in the secretory pathway, subsequent data have not fully supported this conclusion. Alternatively, Bfr1p has also been found by yeast two-hybrid analysis to interact with Bbp1p, a component of the spindle pole body. Finally, we have reported that Bfr1p associates with cytoplasmic mRNP complexes containing Scp160p, raising the possibility that Bfr1p may function in mRNA metabolism. Here, we have explored this possibility further. We report that Bfr1p associates with yeast polyribosomes and mRNP complexes even in the absence of Scp160p, and that its interaction with Scp160p-containing mRNP complexes is RNA-dependent. Furthermore, we have determined by fluorescence microscopy and subcellular fractionation that Bfr1p and Scp160p demonstrate similar cytoplasmic localization with enrichment around the nuclear envelope/endoplasmic reticulum. Finally, we report that loss of Bfr1p disrupts the interaction of Scp160p with polyribosomes, thereby demonstrating that the relationship between these two proteins is functional as well as physical. Considered together, these data raise the intriguing possibility that Bfr1p may provide a link between mRNA metabolism, the chromosomal segregation machinery and perhaps secretion in yeast. 相似文献
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796.
Jonathan H. Clarke Judith I. Laurie Harry J. Gilbert Geoffrey P. Hazlewood 《FEMS microbiology letters》1991,83(3):305-309
Cellulomonas fimi genomic DNA encoding xylanase activity has been cloned and expressed in Escherichia coli. As judged by DNA hybridization and restriction analysis, twelve xylanase-positive clones carried a minimum of four different xylanase (xyn) genes. The encoded enzymes were devoid of cellulase activity but three of the four bound to Avicel. 相似文献
797.
Christelle Boileau Johanne Martel-Pelletier Judith Caron Philippe Msika Georges B Guillou Caroline Baudouin Jean-Pierre Pelletier 《Arthritis research & therapy》2009,11(2):R41-9
Introduction
The aims of this study were, first, to investigate the in vivo effects of treatment with avocado/soybean unsaponifiables on the development of osteoarthritic structural changes in the anterior cruciate ligament dog model and, second, to explore their mode of action. 相似文献798.
799.
Lahn D. Straney Janet E. Bray Ben Beck Judith Finn Stephen Bernard Kylie Dyson Marijana Lijovic Karen Smith 《PloS one》2015,10(10)
BackgroundOut-of-hospital cardiac arrest (OHCA) remains a major public health issue and research has shown that large regional variation in outcomes exists. Of the interventions associated with survival, the provision of bystander CPR is one of the most important modifiable factors. The aim of this study is to identify census areas with high incidence of OHCA and low rates of bystander CPR in Victoria, AustraliaMethodsWe conducted an observational study using prospectively collected population-based OHCA data from the state of Victoria in Australia. Using ArcGIS (ArcMap 10.0), we linked the location of the arrest using the dispatch coordinates (longitude and latitude) to Victorian Local Government Areas (LGAs). We used Bayesian hierarchical models with random effects on each LGA to provide shrunken estimates of the rates of bystander CPR and the incidence rates.ResultsOver the study period there were 31,019 adult OHCA attended, of which 21,436 (69.1%) cases were of presumed cardiac etiology. Significant variation in the incidence of OHCA among LGAs was observed. There was a 3 fold difference in the incidence rate between the lowest and highest LGAs, ranging from 38.5 to 115.1 cases per 100,000 person-years. The overall rate of bystander CPR for bystander witnessed OHCAs was 62.4%, with the rate increasing from 56.4% in 2008–2010 to 68.6% in 2010–2013. There was a 25.1% absolute difference in bystander CPR rates between the highest and lowest LGAs.ConclusionSignificant regional variation in OHCA incidence and bystander CPR rates exists throughout Victoria. Regions with high incidence and low bystander CPR participation can be identified and would make suitable targets for interventions to improve CPR participation rates. 相似文献
800.