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101.
Z Hijazi Z Wang Q Cao P Koenig D Waight R Lang 《Catheterization and cardiovascular interventions》2001,52(2):194-199
Transesophageal echocardiography (TEE) has been employed successfully for guiding transcatheter device closure of secundum atrial septal defect (ASD) and patent foramen ovale (PFO). However, the use of TEE for device closure requires general anesthesia. Intracardiac echocardiography (ICE) can provide similar anatomical views that might replace the use of TEE for device closure. Eleven patients (eight female/three male) with secundum ASD and PFO associated with strokes underwent attempts at transcatheter closure of their defects under sequential TEE and ICE guidance (six patients) and under ICE alone (five patients). The ages of the patients ranged from 6.6 to 74.7 yr, and their weights ranged from 23 to 124.5 kg. The sizes of the defects, as measured by TEE (six patients), ranged from 3 to 27 mm and, as measured by ICE (11 patients), from 3 to 27 mm. The balloon-stretched diameter of the ASD, as measured by TEE (six patients), ranged from 16 to 38 mm and, as measured by ICE (11 patients), from 16 to 35 mm. Both techniques correlated well for the measured two-dimensional diameter and for the balloon-stretched diameter (r = 0.97 and 0.98, respectively). Both TEE and ICE provided similar views of the defects and the various stages of device deployment. Owing to the proximity of the left atrium to the esophagus, however, the images obtained by ICE were more helpful and informative than those obtained by TEE. All patients experienced successful device placement (six patients under both TEE and ICE; five patients under ICE guidance alone); complete closure of the defects was effected in nine patients, whereas two patients had small residual shunts. There were no complications. We conclude that ICE provides unique images of the atrial communications and measurements similar to those obtained by TEE. ICE potentially could replace TEE as a guiding imaging tool for ASD and PFO device closure, thus eliminating the need for general anesthesia. 相似文献
102.
Child-Pugh versus MELD score in predicting survival in patients undergoing transjugular intrahepatic portosystemic shunt 总被引:27,自引:0,他引:27
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Angermayr B Cejna M Karnel F Gschwantler M Koenig F Pidlich J Mendel H Pichler L Wichlas M Kreil A Schmid M Ferlitsch A Lipinski E Brunner H Lammer J Ferenci P Gangl A Peck-Radosavljevic M 《Gut》2003,52(6):879-885
BACKGROUND: In patients undergoing transjugular intrahepatic portosystemic shunt (TIPS), prognostic scores may identify those with a poor prognosis or even those with a clear survival benefit. The Child-Pugh score (CPS) is well established but several drawbacks have led to development of the model of end stage liver disease (MELD). AIM: The aim of the study was to compare the predictive power of CPS and MELD, to validate the original MELD formula, and to assess the predictive value of the determinants used in the two prognostic scores outside of a study setting. PATIENTS: A total of 501 patients underwent elective TIPS placement and 475 patients fulfilled the inclusion criteria. METHODS: Data of all patients undergoing elective TIPS in one university hospital and four community hospitals in Vienna, Austria, between 1991 and 2001, were analysed retrospectively. The main statistical tests were Cox proportional hazards regression model, the log rank test, Kaplan-Meier analysis, and concordance c statistics. RESULTS: Median follow up was 5.2 years and median survival was 4.6 years. During follow up, 230 patients died, 75 within three months after TIPS placement. In stepwise proportional hazards analyses, independent predictors of death were creatinine level, bilirubin level, age, and refractory ascites. MELD was better in predicting survival in a stepwise Cox model but both scores were equally predictive in c statistics for one month, three month, and one year survival. Renal function was the strongest independent predictor of survival. CONCLUSIONS: Although MELD was the primary predictor of overall survival in multivariate analysis, c statistics showed that both scores can be used for patients undergoing TIPS with equal accuracy. For assessing prognosis in patients undergoing TIPS implantation, there seems little reason to replace the well established Child-Pugh score. 相似文献
103.
104.
Nikhil Sasidharan Marija Sumakovic Mandy Hannemann Jan Hegermann Jana F. Liewald Christian Olendrowitz Sabine Koenig Barth D. Grant Silvio O. Rizzoli Alexander Gottschalk Stefan Eimer 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(46):18944-18949
Neurons secrete neuropeptides from dense core vesicles (DCVs) to modulate neuronal activity. Little is known about how neurons manage to differentially regulate the release of synaptic vesicles (SVs) and DCVs. To analyze this, we screened all Caenorhabditis elegans Rab GTPases and Tre2/Bub2/Cdc16 (TBC) domain containing GTPase-activating proteins (GAPs) for defects in DCV release from C. elegans motoneurons. rab-5 and rab-10 mutants show severe defects in DCV secretion, whereas SV exocytosis is unaffected. We identified TBC-2 and TBC-4 as putative GAPs for RAB-5 and RAB-10, respectively. Multiple Rabs and RabGAPs are typically organized in cascades that confer directionality to membrane-trafficking processes. We show here that the formation of release-competent DCVs requires a reciprocal exclusion cascade coupling RAB-5 and RAB-10, in which each of the two Rabs recruits the other’s GAP molecule. This contributes to a separation of RAB-5 and RAB-10 domains at the Golgi–endosomal interface, which is lost when either of the two GAPs is inactivated. Taken together, our data suggest that RAB-5 and RAB-10 cooperate to locally exclude each other at an essential stage during DCV sorting. 相似文献
105.
Wendling Adam L. Byun Sharon Y. Koenig Megan Vasilopoulos Terrie 《Archives of gynecology and obstetrics》2020,301(1):179-187
Archives of Gynecology and Obstetrics - Oral carbohydrate consumption before surgery improves insulin sensitivity, cardiac output and well-being, and shortens hospital stays without adverse... 相似文献
106.
107.
Apoorva Sikka Hamidreza Jamalabadi Marina Krylova Sarah Alizadeh Johan N. van der Meer Lena Danyeli Matthias Deliano Petya Vicheva Tim Hahn Thomas Koenig Deepti R. Bathula Martin Walter 《Human brain mapping》2020,41(9):2334-2346
Electroencephalogram (EEG) microstates that represent quasi‐stable, global neuronal activity are considered as the building blocks of brain dynamics. Therefore, the analysis of microstate sequences is a promising approach to understand fast brain dynamics that underlie various mental processes. Recent studies suggest that EEG microstate sequences are non‐Markovian and nonstationary, highlighting the importance of the sequential flow of information between different brain states. These findings inspired us to model these sequences using Recurrent Neural Networks (RNNs) consisting of long‐short‐term‐memory (LSTM) units to capture the complex temporal dependencies. Using an LSTM‐based auto encoder framework and different encoding schemes, we modeled the microstate sequences at multiple time scales (200–2,000 ms) aiming to capture stably recurring microstate patterns within and across subjects. We show that RNNs can learn underlying microstate patterns with high accuracy and that the microstate trajectories are subject invariant at shorter time scales (≤400 ms) and reproducible across sessions. Significant drop in the reconstruction accuracy was observed for longer sequence lengths of 2,000 ms. These findings indirectly corroborate earlier studies which indicated that EEG microstate sequences exhibit long‐range dependencies with finite memory content. Furthermore, we find that the latent representations learned by the RNNs are sensitive to external stimulation such as stress while the conventional univariate microstate measures (e.g., occurrence, mean duration, etc.) fail to capture such changes in brain dynamics. While RNNs cannot be configured to identify the specific discriminating patterns, they have the potential for learning the underlying temporal dynamics and are sensitive to sequence aberrations characterized by changes in metal processes. Empowered with the macroscopic understanding of the temporal dynamics that extends beyond short‐term interactions, RNNs offer a reliable alternative for exploring system level brain dynamics using EEG microstate sequences. 相似文献
108.
Gomard-Mennesson E Ruivard M Koenig M Woods A Magy N Ninet J Rousset H Salles G Broussolle C Sève P 《Lupus》2006,15(4):223-231
The aim of this study was to evaluate the response to treatment and the long-term outcome in a cohort of patients in whom severe autoimmune hemolytic anaemia (AHA) was the leading manifestation of systemic lupus erythematosus (SLE). Twenty-six women with severe isolated AHA were included. Corticosteroids were used as the initial treatment for all patients in our study. An initial response was obtained in all but one patient (96%). The overall recurrence rate was three per 100 person-years, with an expected recurrence-free proportion of 73% with a 180 months median follow-up. Seven patients (27%) experienced a relapse of AHA. We found a higher proportion of pleuritis in relapsing patients. Only three patients experienced multiple relapses despite splenectomy and several immunosuppressants. Steroid-sparing effect of hydroxychloroquine and azathioprine could not be assessed because most of the patients received these treatments for other reasons than AHA. Intravenous immunoglobulins induced transient response in three cases. Splenectomy was efficient to definitively control AHA in one patient but two patients quickly experienced relapses while one patient did not benefit. Five patients received immunosuppressants that induced only transient responses. Rituximab was long-term efficient in one case. In conclusion, severe AHA is a serious complication of SLE that warrants appropriate management. On the basis of our experience, the ideal treatment of isolated AHA should be oral corticosteroids in first-line treatment. Our study does not support an important role for splenectomy. Patients refractory to conventional therapy should be treated either with few toxic immunosuppressive drugs, danazol or rituximab. 相似文献
109.
Possible founder effect of rapsyn N88K mutation and identification of novel rapsyn mutations in congenital myasthenic syndromes 总被引:2,自引:0,他引:2
110.
目的数值模拟抗血管生成因子Angiostatin和Endostatin对肿瘤血管生成的影响。方法建立肿瘤内外血管生成的二维离散数学模型。模型耦合两种抗血管生成因子Angiostatin和Endostatin的抑制效应,数值模拟在促血管生成因子诱导下肿瘤微血管网生成,讨论血管生成抑制因子的影响。结果抗血管生成因子Angiostatin对肿瘤内外血管网络生成的速度和成熟度有抑制作用。抗血管生成因子Angiostatin和Endostatin耦合作用时,在肿瘤血管生成的早期有明显的抑制效应;在肿瘤血管生成的中后期,它们可以降低肿瘤血管化程度。结论本文模型能够较好的模拟抗血管生成因子Angiostatin和Endostatin对内皮细胞迁移和增殖的抑制作用。 相似文献