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991.
Combined PET/MRI systems are now commercially available and are expected to change the medical imaging field by providing combined anato-metabolic image information. We believe this will be of particular relevance in imaging of cancer patients. At the Department of Clinical Physiology, Nuclear Medicine & PET at Rigshospitalet in Copenhagen we installed an integrated PET/MRI in December 2011. Here, we describe our first clinical PET/MR cases and discuss some of the areas within oncology where we envision promising future application of integrated PET/MR imaging in clinical routine. Cases described include brain tumors, pediatric oncology as well as lung, abdominal and pelvic cancer. In general the cases show that PET/MRI performs well in all these types of cancer when compared to PET/CT. However, future large-scale clinical studies are needed to establish when to use PET/MRI. We envision that PET/MRI in oncology will prove to become a valuable addition to PET/CT in diagnosing, tailoring and monitoring cancer therapy in selected patient populations.  相似文献   
992.
    
Nasal airways resistance was measured in ten patients with allergic rhinitis during intranasal application of an extract of grass pollen. Pretreatment with placebo did not inhibit the increase in nasal airways resistance, whereas ICI 74,917 administered from a pressurized aerosol gave almost complete protection. ICI 74,917 was well tolerated and no evidence was obtained of local hyposensitization during the period of the study.  相似文献   
993.
    
The dynamic experiments on the fixed bed reactor consist of periodic changes in inlet conditions as well as start-up and step disturbances. The experimental results are compared with simulations using a simple one dimensional homogeneous model.The model parameters are determined in mutually independent groups. One group is the kinetic parameters which have been estimated in Ref.[1]. Another group is the heat transport parameters found from heat regenerator experiments. The experiments and the estimation method are described in this paper. The results show that the thermal residence time should be augmented 10% in order to account for the combined effect of radial velocity profile, nonadiabaticy and dynamic heat exchange with the reactor insulation. The estimated total heat transport Peclet number is high indicating that no dispersion phenomena apart from those characteristic for a packed bed are present.The agreement between simulations and experiments is fine for all types of experiments.The effect of radial velocity profile has been investigated separately. This involves solution of a model with two spatial dimensions. Through using a double collocation method combined with Runge-Kutta integration of the ordinary differential equations reasonable calculation times have been obtained.  相似文献   
994.
995.
Enterobacter sakazakii represents a rare opportunistic pathogen that causes a high mortality rate. Especially newborns are infected by contaminated infant formula. To reduce this risk, the EU directive 2073/2005 demands for the absence of the pathogen in 30 ×10 g infant formula. We describe a PCR-/real-time PCR that specifically detected 32 E. sakazakii strains among 21 species of Enterobacteriaceae as well as contaminated specimens among 30 different brands of infant formula. This real-time PCR, performed after a selective enrichment of E. sakazakii, reduces the working time by 1 to 3 days in comparison to the detection methods recommended by the US Food and Drug Administration (FDA) and ISO/DTS 22964 that is still under revision. In contrast to the latter procedure, we detected contaminated specimens of infant formula by the use of the procedure described in this report and the FDA method.  相似文献   
996.
Moving Out of the Lab: Deploying Pervasive Technologies in a Hospital   总被引:2,自引:0,他引:2  
The authors deployed a distributed system containing a location-tracking system, a context-awareness system, wall-sized displays, and mobile phones in a Danish hospital's operating ward. This article presents the lessons they learned from deploying these pervasive computing technologies and a checklist of questions for researchers to consider relating to hardware, software, and organizational issues when moving pervasive systems out of the laboratory. This article is part of a special issue on Real-World Deployments.  相似文献   
997.
Data Management in the Worldwide Sensor Web   总被引:1,自引:0,他引:1  
Harvesting the benefits of a sensor-rich world presents many data management challenges. Recent advances in research and industry aim to address these challenges. With the rapidly increasing number of large-scale sensor network deployments, the vision of a worldwide sensor Web is close to becoming a reality.  相似文献   
998.
The yeast Saccharomyces cerevisiae was examined as host for heterologous expression of the G protein-coupled VPAC1 receptor. Rat VPAC1 receptor cDNA and two chimeric constructs encoding the yeast mating factor pre-pro alpha-leader peptide fused in-frame to rat VPAC1 receptor were expressed in yeast cells under control of a galactose inducible promoter. The rat VPAC1 receptor was fused to the HSV tag epitope to ensure proper immunological detection of the receptor. Crucial conditions for high-level expression of active rat VPAC1 receptor included growth in amino acid supplemented minimal medium, fusion to the yeast alpha-leader peptide and a temperature shift from 30 degrees C to 15 degrees C before promoter induction. Western blotting showed that the expressed receptor was highly glycosylated and a band of 47 kDa was obtained upon endoglycosidase H treatment. Binding with radioiodinated vasoactive intestinal polypeptide revealed a KD of 2.5 nM and an IC50 of 15 nM when displacing with unlabeled vasoactive intestinal polypeptide. VPAC1 receptor density quantified by Western blotting was 510 pmol/mg membrane protein of which only 66 pmol/mg were able to bind vasoactive intestinal polypeptide.  相似文献   
999.
The activities of endoprotease, aminopeptidase, carboxypeptidase and invertase (cotyledon and pulp) were studied in unfermented beans of 10 genotype samples with different flavour characteristics (high and low cocoa flavour). Analysis of variance showed that significant differences in enzyme activities exist between certain genotypes. Aminopeptidase and endoprotease activities in beans of the PA7 genotype were higher than in all others. Principal component analysis (PCA) showed that the PA7 genotype (high cocoa flavour) was very different from the UIT1 genotype (low cocoa flavour). Although significant differences exist, no simple and general relationship is established between the flavour potential of a genotype and the level of key enzyme activities in unfermented beans. Carboxypeptidase is of key importance for peptide and free amino acid formation, but differences in enzyme activity could not be correlated to flavour potential of the genotype. It is suggested that the level of enzyme activities present in unfermented beans is not a limiting factor for optimal formation of flavour precursors during the fermentation process. © 2000 Society of Chemical Industry  相似文献   
1000.
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