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51.
Kasprzak JD Borkowski M Rogowski W Drozdz J Krzemińska-Pakula M 《The international journal of cardiovascular imaging》2002,18(1):25-30
Muscular interventricular septum is an extremely rare location for congenital aneurysm. A 48-year-old patient with a muscular interventricular septum aneurysm coexisting with atrial septal defect, pulmonary stenosis and ventricular preexcitation is presented. Three-dimensional echocardiographic reconstruction of the lesion aided in a precise morphologic and quantitative assessment of the condition. The review of 10 previously reported patients with the entity is presented. 相似文献
52.
Pawel Mierczynski Lukasz Szkudlarek Karolina Chalupka Waldemar Maniukiewicz Satriyo K. Wahono Krasimir Vasilev Malgorzata I. Szynkowska-Jozwik 《Materials》2021,14(9)
This work provides valuable information about unexplored catalytic systems tested in the transesterification reaction of vegetable oil with methanol. It was demonstrated that natural zeolite treatment leads to enhanced catalytic activity and yield of biodiesel production. The activation of the catalytic material in a mixture of 5% H2–95% Ar resulted in an improvement of the values of the TG conversion and fatty acid methyl esters (FAME) yield. In addition, it was proven that the incorporation of CaO, MgO and SrO oxides onto the natural zeolite surface improves the TG conversion and FAME yield values in the transesterification reaction. 相似文献
53.
Kamil Dydek Anna Boczkowska Rafa Kozera Pawe Duraek ukasz Sarniak Magorzata Wilk Waldemar ogin 《Materials》2021,14(11)
The main aim of this work was the investigation of the possibility of replacing the heavy metallic meshes applied onto the composite structure in airplanes for lightning strike protection with a thin film of Tuball single-wall carbon nanotubes in the form of ultra-light, conductive paper. The Tuball paper studied contained 75 wt.% or 90 wt.% of carbon nanotubes and was applied on the top of carbon fibre reinforced polymer before fabrication of flat panels. First, the electrical conductivity, impact resistance and thermo-mechanical properties of modified laminates were measured and compared with the reference values. Then, flat panels with selected Tuball paper, expanded copper foil and reference panels were fabricated for lightning strike tests. The effectiveness of lightning strike protection was evaluated by using the ultrasonic phased-array technique. It was found that the introduction of Tuball paper on the laminates surface improved both the surface and the volume electrical conductivity by 8800% and 300%, respectively. The impact resistance was tested in two directions, perpendicular and parallel to the carbon fibres, and the values increased by 9.8% and 44%, respectively. The dynamic thermo-mechanical analysis showed higher stiffness and a slight increase in glass transition temperature of the modified laminates. Ultrasonic investigation after lightning strike tests showed that the effectiveness of Tuball paper is comparable to expanded copper foil. 相似文献
54.
Oleksandr Shtyka Waldemar Maniukiewicz Radoslaw Ciesielski Adam Kedziora Viktar Shatsila Tomasz Sieraski Tomasz Maniecki 《Materials》2021,14(12)
In the present work, for the first time, the possibility of formation of CrAl2O4 was shown from the equimolar mixture of co-precipitated Al2O3 and Cr2O3 oxides under a reductive environment. The crystallographic properties of the formed compound were calculated using the DICVOL procedure. It was determined that it has a cubic crystal structure with space group Fd-3m and a unit cell parameter equal to 8.22(3) Å. The formed CrAl2O4 is not stable under ambient conditions and easily undergoes oxidation to α-Al2O3 and α-Cr2O3. The overall sequence of the phase transformations of co-precipitated oxides leading to the formation of spinel structure is proposed. 相似文献
55.
Diego A. Lara Mary K. Olive James F. George Robert N. Brown Waldemar F. Carlo Edward V. Colvin Brad L. Steenwyck F. Bennett Pearce 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2014,41(1):21-25
Coronary spasm during coronary angiography for vasculopathy in children can be prevented by the intracoronary administration of nitroglycerin. We reviewed the anesthesia and catheterization reports and charts for pediatric transplant recipients who underwent angiography from 2005 through 2010. Correlation analysis was used to study the relation of post-injection systolic blood pressure (SBP) to nitroglycerin dose. Forty-one angiographic evaluations were performed on 25 patients (13 male and 12 female). Mean age was 9.9 ± 3.2 years (range, 3.3–16.1 yr). The mean total dose of nitroglycerin was 2.93 ± 1.60 µg/kg (range, 1–8 µg/kg).There was a significant drop between the baseline SBP (mean, 106 ± 21.6 mmHg) and the lowest mean SBP before nitroglycerin administration (78 ± 13.2, P <0.0001, paired t test). There was no significant additional change in SBP (mean after nitroglycerin administration, 80.7 ± 13.1 mmHg; P = 0.2). There was a significant drop in lowest heart rate between baseline (109 ± 16.5 beats/min) and before nitroglycerin administration (89 ± 14.3 beats/min; P <0.0001, paired t test). There was no significant additional change in heart rate (mean heart rate after nitroglycerin, 84 ± 17.7 beats/min; P = 0.09). There were 2 interventions for SBP before nitroglycerin and 2 after nitroglycerin. One child experienced a transient ST-T–segment change during angiography after nitroglycerin. In the highest dose range, the additional decrease in SBP was 7.2 mmHg (P=0.03). Routine intracoronary nitroglycerin administration in this dose range produced no significant changes in SBP or heart rate in children.Key words: Child, coronary angiography, coronary vasospasm/etiology, dose-response relationship, drug, heart transplantation/adverse effects, hemodynamics/drug effects, nitroglycerin/administration & dosage/therapeutic use, postoperative complications/therapy, retrospective studies, vasodilation/drug effectsAllograft coronary disease in children occurs with increasing frequency after transplantation, as a function of time. In a multicenter study,1 the incidence of coronary artery disease in children 5 years post-transplant was 17% of all recipients. Coronary angiography remains the gold standard in the detection of vasculopathy in heart-transplant recipients.2 Coronary artery spasm can complicate selective coronary angiography and result in myocardial ischemia. Coronary spasm can simulate the angiographic appearance of graft vasculopathy and cause diagnostic confusion.3 The spasm can arise from manipulation of the arterial wall by the catheter or from intraluminal injection of contrast material. In cardiac transplant recipients, coronary artery spasm has been reported in as many as 4.9% of coronary angiograms.3In adults, intracoronary nitroglycerin is routinely administered during coronary angiography to prevent coronary artery spasm.4 In children, however, safety and dosage guidelines for intracoronary nitroglycerin have not yet been firmly established. A dose of 3 µg/kg can be extrapolated by weight from the established adult dose of 200 µg; this dose was used in a study of children after the arterial switch operation and was shown to produce coronary vasodilation—with a small reduction in systolic blood pressure (SBP) and no noteworthy change in heart rate—in a control group of patients.5,6We previously reported a case of coronary artery spasm during routine coronary angiographic monitoring in a 9-year-old boy who had undergone heart transplantation as an infant.7 After left main coronary artery injection of contrast material, the patient''s left anterior descending and left circumflex coronary arteries appeared to be diffusely narrow, and he developed marked ST-segment elevation, hypotension, and ventricular tachycardia. After cardiopulmonary resuscitation, he recovered uneventfully and displayed normal systolic function. Coronary angiography one month later, with the administration of intracoronary nitroglycerin before the injection of contrast material, revealed normal coronary artery diameter and was accomplished without complication.Since 2005, intracoronary nitroglycerin has routinely been used in pediatric transplant patients during biennial selective coronary angiographic monitoring at our institution. The purpose of the study is to report our experience with the routine use of intracoronary nitroglycerin for coronary angiography in children: its effects on blood pressure, on heart rate, and on the occurrence of arrhythmia and ST-segment elevation. 相似文献
56.
57.
Damon E. Houghton Ana I. Casanegra Lisa G. Peterson Jordan Cochuyt David O. Hodge Danielle Vlazny Robert D. McBane David Froehling Waldemar E. Wysokinski 《American journal of hematology》2020,95(7):817-823
Randomized controlled trials leading to the approval of apixaban and rivaroxaban for venous thromboembolism (VTE) did not include patients with upper extremity deep vein thrombosis (UE-DVT). We sought to evaluate the safety and effectiveness of rivaroxaban and apixaban for the treatment of acute UE-DVT. Consecutive patients with VTE enrolled into the Mayo Clinic VTE Registry, between March 1, 2013 and December 31, 2019, were followed prospectively. Clinical, demographic and imaging data were collected at the time of study recruitment. Patients with a diagnosis of acute UE-DVT who received rivaroxaban, apixaban, LMWH or warfarin were included. Recurrent VTE, major bleeding, clinical-relevant non-major bleeding (CRNMB), and death were assessed at 3-month intervals. During the study period, 210 patients with acute UE-DVT were included; 63 were treated with apixaban, 39 with rivaroxaban, and 108 with LWMH and/or warfarin. Overall 51% had catheter-associated UE-DVT, 60% had a diagnosis of malignancy, and 14% had concurrent pulmonary embolism. Malignancy was more common in patients treated with LMWH/warfarin (67% vs 52%, P = .03). At 3 months of follow up, one (0.9%) recurrent VTE occurred in a patient treated with LMWH/warfarin and one (1.0%) patient treated with apixaban or rivaroxaban (P = .97). Major bleeding occurred in three patients treated with LMWH/warfarin, and in none of those treated with apixaban or rivaroxaban (P = .09). Clinical-relevant non-major bleeding occurred in one patient (0.9%) treated with LWMH/warfarin and two patients (2.0%) treated with apixaban or rivaroxaban (P = .53). Treatment of UE-DVT with apixaban or rivaroxaban appears to be as safe and effective as LMWH/warfarin. 相似文献
58.
Houghton Damon E. Lekah Alexander Macedo Thanila A. Hodge David Saadiq Rayya A. Little Yvonne Casanegra Ana I. McBane Robert D. Wysokinski Waldemar E. 《Journal of thrombosis and thrombolysis》2020,49(2):199-205
Journal of Thrombosis and Thrombolysis - Thrombosis resolution is an important component of treatment for deep vein thrombosis (DVT) and multiple anticoagulants are now available. It is unknown... 相似文献
59.
Tomasz Rojek Waldemar Goldeman Katarzyna
lepokura Marek Duczmal Agnieszka Wojciechowska Ewa Matczak-Jon 《RSC advances》2019,9(54):31497
Three novel coordination compounds based on α,α-disubstituted analogues of zoledronic acid with a cyclopropane (cpp) or cyclobutane (cbt) ring on the Cα carbon, isomorphous [Co(H2cppZol)(H2O)]·H2O (1a), [Ni(H2cppZol)(H2O)]·H2O (1b) and [Co(H2cbtZol)(H2O)]·H2O (2a), were synthesized under hydrothermal conditions at low pH. Single-crystal X-ray diffraction analysis revealed that all the compounds had a 1D double zig–zag chain architecture with an 8 + 8 ring motif formed by alternately arranged symmetrical (–O–P–O–)2 bridges linking equivalent octahedral metal centres. Both the ligand coordination mode and chain architecture displayed by 1a, 1b and 2a are unique among 1D [M(H2L)(H2O)x]·yH2O coordination polymers based on nitrogen-containing bisphosphonates reported so far. All the compounds exhibit similar decomposition pathways upon heating with thermal stabilities decreasing in the order 1b > 1a > 2a. The IR spectra revealed that lattice water release above 227, 178 and 97 °C, respectively, does not change the chain architecture leaving them intact up to ca. 320, 280 and 240 °C. Magnetic behaviour investigations indicated that 1a, 2a and 1b exhibit weak alternating antiferromagnetic–ferromagnetic exchange interactions propagated between the magnetic centres through double (–O–P–O–)2 bridges. The boundary between antiferro- and ferromagnetic couplings for the Co–O⋯O–Co angle in 1a and 2a was estimated to be ca. 80°. This value is also applicable for recently reported [M3(HL)2(H2O)6]·6H2O (M = Co, Ni) complexes based on α,α-disubstituted analogues of zoledronic acid and can be used to the explain magnetic behaviour of 1b.1D Co(ii)/Ni(ii) coordination polymers with alternating antiferromagnetic–ferromagnetic exchange interactions between metal centers propagated through double (–O–P–O–)2 bridges. 相似文献
60.
Waldemar Gorka Amir Kagalwalla Brian J. McParland Yasmeen Kagalwalla Abdullah Al Zaben 《Journal of clinical ultrasound : JCU》1996,24(6):287-295
We have correlated flow abnormalities in the hepatic vasculature with histological findings in the liver to determine the accuracy of Doppler ultrasound in the diagnosis of liver cirrhosis in children. Eighteen children admitted for evaluation of unknown liver disease were examined prospectively and blindly with Doppler ultrasound prior to liver biopsy. Biopsy specimens showed established cirrhosis in 9 of 18, early cirrhosis in 5 of 18, and no cirrhosis in 4 of 18 children. Doppler studies were also performed on 20 control subjects. The portal vein velocity was decreased (p < 0.0005) and the arterio-portal velocity ratio was increased (p < 0.0005) in the established cirrhosis cohort relative to the controls. For the criteria of the established cirrhosis cohort, the sensitivities of the loss of the reverse flow component in the hepatic veins, the arterio-portal velocity ratio being greater than 3.0, the portal vein velocity being less than 20 cm/s, and the existence of focal flow acceleration in the hepatic veins were 100%, 78%, 67%, and 44%, respectively. The specificity of all of these criteria was 100%. The indicators were not useful in the diagnosis of early cirrhosis. © 1996 John Wiley & Sons, Inc. 相似文献