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排序方式: 共有878条查询结果,搜索用时 15 毫秒
21.
C. Kim S. D. Harlow C. A. Karvonen‐Gutierrez J. F. Randolph Jr M. Helmuth S. Kong B. Nan R. Carlos 《Diabetic medicine》2013,30(12):1433-1441
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Klaus v. Olshausen Eva Amann Manfred Hofmann Franz Schwarz Helmuth C. Mehmel Wolfgang Kübler 《The American journal of cardiology》1984,54(1):142-146
The influence of aortic valve replacement on the incidence of ventricular arrhythmias was studied by 24-hour Holter electrocardiographic monitoring in 45 patients immediately before and 14 ± 7 months after operation. Ventricular arrhythmias were graded according to the Lown criteria. Preoperative left ventricular (LV) ejection fraction (EF) was determined by angiography and postoperative LVEF by gated blood pool scintigraphy. Repetitive ventricular arrhythmias (Lown grade 4A/B) were associated with a reduced LVEF (< 55%) before and after operation. In 24 patients with preoperative normal LVEF (>- 55%) (group A), mean LVEF remained unchanged after operation (72% vs 71 %). Pre- and postoperative ventricular premature complex (VPC) frequency (45 ± 99 vs 39 ± 94 VPC/24 hours and grade (1.3 vs 1.4) were not significantly different. However, in 17 patients with preoperative impaired LVEF (< 55%) (group B, LVEF preoperatively 40 ± 8%) and marked postoperative improvement (> 10%) (LVEF postoperatively 64 ± 7%), mean VPC frequency decreased from 536 to 69 VPCs/24 hours and mean VPC grade was reduced from 3.8 to 1.5. Complex VPCs were found preoperatively in all 17 patients of group B, but in only 5 patients after operation. Four patients had a reduced LVEF preoperatively and it did not improve postoperatively (group C). Postoperative Holter monitoring detected ventricular tachycardia in all 4 patients.This study indicates that repetitive VPCs are infrequent in patients with normal LVEF before and late after aortic valve replacement. In patients with impaired LVEF and complex VPCs preoperatively, the postoperative improvement of LV function is usually accompanied by a reduction of frequent and complex VPCs. 相似文献
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Idoia Martin‐Guerrero Birgit Burkhardt Markus Kreuz Thorsten Zenz Ilske Oschlies Norbert Arnold Michael Baudis Susanne Bens Africa García‐Orad Jasmin Lisfeld Carsten Schwaenen Monika Szczepanowski Swen Wessendorf Michael Pfreundschuh Lorenz Trümper Wolfram Klapper Reiner Siebert 《Genes, chromosomes & cancer》2013,52(2):150-155
Translocations affecting chromosome subband 6p25.3 containing the IRF4 gene have been recently described as characteristic alterations in a molecularly distinct subset of germinal center B‐cell‐derived lymphomas. Secondary changes have yet only been described in few of these lymphomas. Here, we performed array‐comparative genomic hybridization and molecular inversion probe microarray analyses on DNA from 12 formalin‐fixed paraffin‐embedded and two fresh‐frozen IRF4 translocation‐positive lymphomas, which together with the previously published data on nine cases allowed the extension of copy number analyses to a total of 23 of these lymphomas. All except one case carried chromosomal imbalances, most frequently gains in Xq28, 11q22.3‐qter, and 7q32.1‐qter and losses in 6q13‐16.1, 15q14‐22.31, and 17p. No recurrent copy‐neutral losses of heterozygosity were observed. TP53 point mutations were detected in three of six cases with loss of 17p. Overall this study unravels a recurrent pattern of secondary genetic alterations in IRF4 translocation‐positive lymphomas. © 2012 Wiley Periodicals, Inc. 相似文献
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L. Villa B. Guerra S. Schmoger J. Fischer R. Helmuth Z. Zong A. García-Fernández A. Carattoli 《Antimicrobial agents and chemotherapy》2015,59(10):6597-6600
A Salmonella enterica serovar Corvallis strain was isolated from a wild bird in Germany. This strain carried the IncA/C2 pRH-1238 plasmid. Complete sequencing of the plasmid was performed, identifying the blaNDM-1, blaCMY-16, fosA3, sul1, sul2, strA, strB, aac(6′)-Ib, aadA5, aphA6, tetA(A), mphA, floR, dfrA7, and merA genes, which confer clinically relevant resistance to most of the antimicrobial classes, including β-lactams with carbapenems, fosfomycin, aminoglycosides, co-trimoxazole, tetracyclines, and macrolides. The strain likely originated from the Asiatic region and was transferred to Germany through the Milvus migrans migratory route. 相似文献
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Standardized criteria for diagnosis and response evaluation in chronic lymphocytic leukemia (CLL) are essential to achieve comparability of results and improvement of clinical care. With the increasing range of therapeutic options, the treatment context is important when defining refractory CLL. Refractory CLL has been defined as no response or response lasting ≤ 6 months from last therapy. This subgroup has a very poor outcome, and many trials use this group as an entry point for early drug development. With the intensification of first-line regimens, the proportion of patients with refractory CLL using these criteria decreases. This has immediate consequences for recruitment of patients into trials as well as salvage strategies. Conversely, patients who are not refractory according to the traditional definition but who have suboptimal or short response to intense therapy also have a very poor outcome. In this Perspective, we discuss recent results that may lead to a reassessment of risk categories in CLL focusing on fit patients who are eligible for all treatment options. We cover aspects of the history and biologic basis for refractory CLL and will focus on how emerging data on treatment failure from large trials using chemoimmunotherapy may help to define risk groups in CLL. 相似文献
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Brunner Sarah Heckel Maria Zenz Daniel Ostgathe Christoph Gahr Susanne 《Wiener Medizinische Wochenschrift》2022,172(7):172-180
Wiener Medizinische Wochenschrift - Das Nationale Hospiz- und Palliativregister (NHPR) ist eine Datenbank für palliativmedizinische Einrichtungen zur Dokumentation eines Kerndatensatzes... 相似文献
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Jessica Kramer Amy Rubin Wendy Coster Eric Helmuth John Hermos David Rosenbloom Rich Moed Meghan Dooley Ying‐Chia Kao Kendra Liljenquist Deborah Brief Justin Enggasser Terence Keane Monica Roy Mark Lachowicz 《International journal of methods in psychiatric research》2014,23(1):120-129
Emerging methodological research suggests that the World Wide Web (“Web”) is an appropriate venue for survey data collection, and a promising area for delivering behavioral intervention. However, the use of the Web for research raises concerns regarding sample validity, particularly when the Web is used for recruitment and enrollment. The purpose of this paper is to describe the challenges experienced in two different Web‐based studies in which participant misrepresentation threatened sample validity: a survey study and an online intervention study. The lessons learned from these experiences generated three types of strategies researchers can use to reduce the likelihood of participant misrepresentation for eligibility in Web‐based research. Examples of procedural/design strategies, technical/software strategies and data analytic strategies are provided along with the methodological strengths and limitations of specific strategies. The discussion includes a series of considerations to guide researchers in the selection of strategies that may be most appropriate given the aims, resources and target population of their studies. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献