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排序方式: 共有2631条查询结果,搜索用时 31 毫秒
91.
Martina Zlesk Milena Pavlíkov Adam Pivk imon Maruiak Ondej Jankovský Anna-Marie Lauermannov Michal Lojka Filip Anton
ík Zbyek Pavlík 《Materials》2021,14(6)
The ongoing tendency to create environmentally friendly building materials is nowadays connected with the use of reactive magnesia-based composites. The aim of the presented research was to develop an ecologically sustainable composite material based on MOC (magnesium oxychloride cement) with excellent mechanical, chemical, and physical properties. The effect of the preparation procedure of MOC pastes doped with graphene nanoplatelets on their fresh and hardened properties was researched. One-step and two-step homogenization techniques were proposed as prospective tools for the production of MOC-based composites of advanced parameters. The conducted experiments and analyses covered X-ray fluorescence, scanning electron microscopy, energy-dispersive spectroscopy, high-resolution transmission electron microscopy, sorption analysis, X-ray diffraction, and optical microscopy. The viscosity of the fresh mixtures was monitored using a rotational viscometer. For the hardened composites, macro- and micro-structural parameters were measured together with the mechanical parameters. These tests were performed after 7 days and 14 days. The use of a carbon-based nanoadditive led to a significant drop in porosity, thus densifying the MOC matrix. Accordingly, the mechanical resistance was greatly improved by graphene nanoplatelets. The two-step homogenization procedure positively affected all researched functional parameters of the developed composites (e.g., the compressive strength increase of approximately 54% after 7 days, and 37% after 14 days, respectively) and can be recommended for the preparation of advanced functional materials reinforced with graphene. 相似文献
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Peter Bossuyt Erwin Dreesen Jordi Rimola Sofie Devuysere Yves De Bruecker Ragna Vanslembrouck Valérie Laurent Magaly Zappa Céline Savoye-Collet Benjamin Pariente Jérôme Filippi Filip Baert Geert D’Haens David Laharie Laurent Peyrin-Biroulet Séverine Vermeire 《Clinical gastroenterology and hepatology》2021,19(5):947-954.e2
94.
BACKGROUND: Discharge codes are frequently used to describe hospital activity related to heart failure (HF). OBJECTIVES: To determine whether discharge codes for HF underestimated or overestimated hospital activity related to HF. DESIGN: Patients with atrial fibrillation (AF), who commonly have HF, were identified and their case notes reviewed to identify cases of HF missed by discharge codes. PARTICIPANTS AND METHODS: Patients admitted between November 1997 and January 1998 with either HF or AF. Identification of HF and AF by ICD10 hospital discharge codes. Identification of additional cases of AF from a central hospital-wide ECG database. RESULTS: We identified 330 cases with an ICD 10 code for HF, of which 43 (13%) were deemed to be miscoded, 32 patients (10%) were classified as possible, 39 (12%) as probable and 216 (65%) as definite HF. Results were similar whether or not HF was the primary discharge diagnosis. We identified 452 patients with AF, of whom 45 (10%) were classified as probable and 193 (43%) as definite HF. 129 (54%) of these cases had no diagnostic discharge code for HF. ICD 10 discharge codes for HF were correct in 77% of cases but identified only 66% of patients with probable or definite HF in this analysis. Screening of other diagnoses would have identified further cases of HF. CONCLUSIONS: Hospital discharge codes substantially underestimate hospital events related to HF in the UK. 相似文献
95.
BCR‐ABL1 kinase domain mutational analysis of CD34+ stem/progenitor cells in newly diagnosed CML patients by next‐generation sequencing
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96.
Filip Zemrak Mark A. Ahlman Gabriella Captur Saidi A. Mohiddin Nadine Kawel-Boehm Martin R. Prince James C. Moon William G. Hundley João A.C. Lima David A. Bluemke Steffen E. Petersen 《Journal of the American College of Cardiology》2014
Background
Left ventricular (LV) trabeculation is highly variable among individuals and is increased in some diseases (e.g., congenital heart disease or cardiomyopathies), but its significance in population-representative individuals is unknown.Objectives
The goal of this study was to determine if excessive LV trabeculation in population-representative individuals is associated with preceding changes in cardiac volumes and function.Methods
For technical reasons, the extent of trabeculation, which is expressed as the ratio of noncompacted to compacted (NC/C) myocardium, was measured on cardiac magnetic resonance (CMR) long-axis cine images in 2,742 participants in the MESA (Multi-Ethnic Study of Atherosclerosis) (mean age 68.7 years; 52.3% women; 56.4% with hypertension; 16.8% with diabetes) at examination 5. These were considered in quintiles of trabeculation extent; the NC/C ratio of quintile 5 was 2.46 to 5.41. We determined the relationship between the maximal NC/C ratio and the preceding change (9.5 years between examinations 1 and 5) in end-systolic volume indexed (ESVi) to body surface area. Secondary analyses assessed the associations between the maximal NC/C ratio and preceding changes in end-diastolic volume indexed (EDVi) to body surface area and the ejection fraction (EF).Results
Over 9.5 years, the ESVi decreased by 1.3 ml/m2, the EDVi decreased by 5.1 ml/m2, and the EF decreased by 0.6% (p < 0.0001). Even in subjects with excessive trabeculation, there were no clinically relevant differences in LV volumes and systolic function changes among the quintiles of trabeculation extent.Conclusions
Greater extent of, and even excessive, LV trabeculation measured in end-diastole in asymptomatic population-representative individuals appeared benign and was not associated with deterioration in LV volumes or function during an almost 10-year period. 相似文献97.
Gesa H. Phler Filip Klimes Andreas Voskrebenzev Lea Behrendt Christoph Czerner Marcel Gutberlet Serghei Cebotari Fabio Ius Christine Fegbeutel Christian Schoenfeld Till F. Kaireit Erik F. Hauck Karen M. Olsson Marius M. Hoeper Frank Wacker Jens Vogel‐Claussen 《Journal of magnetic resonance imaging : JMRI》2020,52(2):610-619
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