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31.
Jürgen Vogt Torsten Schwarz Daniel Gras Johannes Sperzel Philippe Ritter Willem de Voogt Jean-Pierre Cebron Martin Seifert Bruce Tockman Bernd Schubert Eric Johnson Annette Doelger Thierry Pochet Elisabeth Mouton Christian Butter 《Journal of interventional cardiac electrophysiology》2007,19(1):61-68
Introduction Failure to enter the coronary sinus (CS) with a guiding catheter and entering its tributaries remains challenging in left
ventricle (LV) pacing lead implants for cardiac resynchronization therapy (CRT). A dual telescoping catheter system (8F outer/6F
inner) is designed to provide the ability to adjust the catheter curve size, shape and/or reach to the patients’ anatomy avoiding
the need for catheter change.
Methods Five different designs for CS cannulation were randomly tested in 64 patients scheduled for CRT device implant.
Results In 33 consecutive patients three adaptable telescoping guiding catheter systems were tested per patient, the adaptable catheters
had higher overall cannulation success rates (68, 63 and 62%) compared to the fixed shape catheter (46%) and an greater cannulation
success rate when the CS location was not known (70, 53 and 72% vs 33% for the fixed shape). In a second group of 31 CRT patients
the two telescoping catheters had similar high levels of success (71–80%), with or without using the inner catheter.
Conclusions The telescopic system is adaptable to a wide range of anatomical variations in patients and can result in a higher CS cannulation
success rate due to its adjustability in the RA in search for the CS ostium. On top of this the inner catheter allows for
sub-selecting the CS tributaries. 相似文献
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34.
Dardo G Tomasi Elisabeth C Caparelli 《Journal of cerebral blood flow and metabolism》2007,27(1):33-42
Brain activation maps of blood oxygenation level dependent (BOLD) signals during functional magnetic resonance imaging (fMRI) are sensitive to unwanted contributions from large vessels. Most BOLD-fMRI studies are based on a stimulus-correlated modulation of the MRI signal amplitude that is sensitive to desired microvascular effects and unwanted macrovascular effects. Aiming to suppress macrovascular effects in activation patterns, this BOLD-fMRI study evaluates brain activation during a verbal working memory task (2-back) in healthy volunteers (n=18) using the amplitude and phase components of the MRI signal. The use of the first time point as a phase reference allowed us to eliminate phase wrapping artifacts and increase the statistical power of 'phase' activation, and this information was used to filter out voxels with significant macrovascular (i.e., draining and pial veins) contribution in 'amplitude' activation patterns. Across subjects, the task produced large modulations of the relative phase in the occipital, dorsolateral prefrontal, and parietal cortices, suggesting a common distribution of draining veins in these regions across subjects, and in the rostral frontal cortex, probably associated to stimulus-correlated motion of the head. The phase filtering method partially suppressed BOLD responses in the superior and lateral prefrontal, parietal, and occipital cortices; therefore the commonly reported brain activation in these cortices during working memory tasks may include significant macrovascular contributions. This study suggests that the phase information embedded in the MRI signal can be used to suppress unwanted macrovascular contributions in fMRI studies. 相似文献
35.
Edward L. Morgan Brandon N. Morgan Elisabeth A. Stein Elizabeth L. Vitrs Marilyn L. Thoman Sam D. Sanderson Joy A. Phillips 《Vaccine》2009
A conformationally biased, agonist of human C5a65–74 (EP67) was assessed for its adjuvant activities in vitro and in vivo. EP67 induced the release of the inflammatory (Th1) type cytokines from C5a receptor (CD88)-bearing antigen presenting cells (APC). EP67 did not induce the release of these cytokines from splenic APCs obtained from C5a receptor knockouts (CD88−/−). Serum from mice immunized with EP67–ovalbumin (OVA) contained high OVA-specific antibody (Ab) titers [IgG1, IgG2a (IGg2c), IgG2b]. Mice receiving OVA alone produced only IgG1 Abs, indicating the ability of EP67 to induce a Th1-like Ab class switch. Spleen cell cultures from wild type mice but not CD88−/− mice showed an enhanced OVA-specific proliferative response in vitro. These results indicate the ability of EP67 to drive a Th1-mediated immune response and its potential use as a unique adjuvant. 相似文献
36.
Fotios A. Asimakopoulos Nicholas J. White Elisabeth P. Nacheva & Anthony R. Green 《British journal of haematology》1995,92(1):127-130
Deletions of chromosome 20q are associated with myeloid malignancies and have been previously shown to arise in a multipotent progenitor of both myeloid and B cells. However, B-cell differentiation from the abnormal progenitor was impaired. The CD40 antigen is a surface glycoprotein which is expressed in B cells and haemopoietic stem cells and is important for B-cell growth and development. Following the recent mapping of CD40 to chromosome 20q we sought to determine its position relative to 20q deletions. Analysis of lymphoblastoid cell lines carrying 20q deletions placed CD40 within a 19–21 cM interval which is almost coincidental with the common deleted region defined by previous analysis of patient samples. Our results raise the possibility that genetic alteration of this locus may contribute to the pathogenesis of myeloid disorders associated with 20q deletions. 相似文献
37.
Elisabeth U. Dexter M.D. John M. Snider M.D. Ellen E.I. Gordon M.D. Wayne E. Richenbacher M.D. 《Journal of cardiac surgery》1997,12(6):412-415
A bstract One etiology of unilateral lobar pulmonary edema is mitral regurgitation. Echocardiography is able to demonstrate the retrograde flow of blood into the pulmonary veins and allows timely diagnosis and treatment planning. Correction of mitral regurgitation is followed by resolution of the radiographic abnormality. 相似文献
38.
Hans Brunner Thomas C Wetter Birgit Hogl Alexander Yassouridis Claudia Trenkwalder Elisabeth Friess 《Movement disorders》2002,17(5):928-933
We investigated non-rapid eye movement (non-REM) sleep in patients with newly diagnosed Parkinson's disease (PD) who had never previously received dopaminergic medication. There were no significant differences in the conventional sleep parameters between de novo patients with PD and a healthy control group, but the length of stage 1 sleep and the number of awakenings increased significantly upon administration of dopaminergic drugs. Analyzing the quantitative electroencephalogram (EEG), we observed a significant reduction in the low-delta frequency range and a nonsignificant increase in the sigma frequency range in de novo patients with PD. The dopaminergic medication also nonsignificantly reduced the low-delta and sigma frequencies, the latter to the level of the controls. Possible mechanisms that may account for the observed differences are discussed. It is suggested that Parkinson's disease as well as the application of dopaminergic drugs exerts a desynchronizing effect on the sleep EEG that is reflected in a disruption of sleep continuity. 相似文献
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40.
Elisabeth Rodier Hubert Lochard Martial Sauceau Jean-Jacques Letourneau Bernard Freiss Jacques Fages 《European journal of pharmaceutical sciences》2005,26(2):184-193
The aim of this study is to improve the dissolution properties of a poorly-soluble active substance, Eflucimibe by associating it with gamma-cyclodextrin. To achieve this objective, a new three-step process based on supercritical fluid technology has been proposed. First, Eflucimibe and cyclodextrin are co-crystallized using an anti-solvent process, dimethylsulfoxide being the solvent and supercritical carbon dioxide being the anti-solvent. Second, the co-crystallized powder is held in a static mode under supercritical conditions for several hours. This is the maturing step. Third, in a final stripping step, supercritical CO(2) is flowed through the matured powder to extract the residual solvent. The coupling of the first two steps brings about a significant synergistic effect to improve the dissolution rate of the drug. The nature of the entity obtained at the end of each step is discussed and some suggestions are made as to what happens in these operations. It is shown the co-crystallization ensures a good dispersion of both compounds and is rather insensitive to the operating parameters tested. The maturing step allows some dissolution-recrystallization to occur thus intensifying the intimate contact between the two compounds. Addition of water is necessary to make maturing effective as this is governed by the transfer properties of the medium. The stripping step allows extraction of the residual solvent but also removes some of the Eflucimibe which is the main drawback of this final stage. 相似文献