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101.
As compared with balloon angioplasty, stent implantation in treatment of acute myocardial infarction (AMI) reduces abrupt vessel closure, restenosis, and reocclusion rate. However, a few studies have demonstrated the safety and feasibility of direct stenting compared to conventional stent implantation technique. This study was designed to compare possible advantages of direct stenting with conventional stent implantation on immediate coronary blood flow and short-term clinical benefits in patients with AMI. Fifty patients with AMI who underwent mechanical revascularization were eligible for the study. The patients were randomly assigned to undergo either direct stenting (n = 25) or conventional stent implantation (n = 25). Before and after the procedure thrombolysis in myocardial infarction (TIMI) flow and postprocedural corrected TIMI frame count (cTFC) of the infarct-related artery were measured. There was no difference in TIMI flow distribution at baseline between the 2 groups. TIMI 3 flow rate significantly increased after procedure in both groups compared to baseline (p < 0.05). Postprocedural cTFC was found significantly lower in the direct stent arm compared to conventional stenting (p < 0.001). Both during and after the procedure the complication rate and procedural time were lower in the direct stenting arm. Direct stenting provides better immediate coronary blood flow and is a safe and feasible method compared with conventional stenting in patients with AMI. Improvement in coronary blood flow measured by the corrected TIMI frame count method may suggests a significant reduction of microvascular injury. 相似文献
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104.
Süheyla
zkutlu MD Canan Ayabakan MD Alpay eliker MD Huda Elshershari MD 《Journal of the American Society of Echocardiography》2002,15(12):1523-1528
We report 12 patients with ventricular noncompaction who were echocardiographically identified at our institution since 1991. The mean age at presentation was 3.5 years. Five patients had isolated noncompaction. Three of them had subnormal left ventricular systolic function at presentation. Noncompaction was associated with complex congenital heart defect in 3 patients. Four patients had simple congenital heart defects: pulmonary stenosis, coarctation of aorta with aberrant origin of right subclavian artery, ventricular septal defect, and partial anomalous pulmonary venous return. The observed rhythm abnormalities were Wolff-Parkinson-White syndrome and paroxysmal supraventricular tachycardia, bigemini ventricular extrasystoles, and left bundle branch block. A transvenous pacemaker was implanted in a patient because of complete heart block. Noncompaction of the ventricular myocardium is rare. Our patients clearly represent the clinical and morphological spectrum of this disorder. Distinct morphological features can be diagnosed on 2-dimensional echocardiography. 相似文献
105.
Güden M Celik E Hizal A Altindiş M Cetiner S 《Journal of biomedical materials research. Part B, Applied biomaterials》2008,85(2):547-555
Sintered Ti6Al4V powder compacts potentially to be used in implant applications were prepared using commercially available spherical and angular powders (100-200 mum) within the porosity range of 34-54%. Cylindrical green powder compacts were cold compacted at various pressures and then sintered at 1200 degrees C for 2 h. The final percent porosity and mean pore sizes were determined as functions of the applied compaction pressure and powder type. The mechanical properties were investigated through compression testing. Results have shown that yield strength of the powder compacts of 40-42% porosity was comparable with that of human cortical bone. As compared with previously investigated Ti powder compacts, Ti6Al4V powder compacts showed higher strength at similar porosity range. Microscopic observations on the failed compact samples revealed that failure occurred primarily by the separation of interparticle bond regions in the planes 45 degrees to the loading axis. 相似文献
106.
Alkan A Burulday V Oztanir N Dogan M Erbay MF Kocak A Aralasmak A 《Medical hypotheses》2012,79(2):129-131
Aim
The purpose of our study was to determine whether the administration of contrast material affects the results of MR Spectroscopy (MRS) in different intraaxial brain tumors.Materials and methods
Thirty-three patients (median range 46.72 ± 2.95, range 9–77) with intraaxial brain tumors underwent MRS before and 5 min after intravenous administration of gadolinium based contrast material at the standard dose of 0.1 mmol/kg (Gadodiamide or Gd-DOTA). Metabolite ratios (N-acetyl aspartate (NAA)/Creatine (Cr), Choline (Cho)/Cr, and NAA/Cho) were calculated.Results
There was no significant difference between the pre and postcontrast MRS spectra as regards to NAA/Cr (p:0.4), Cho/Cr (p:0.2), and NAA/Cho (p:0.2) ratios obtained from the intraaxial brain tumors.Conclusion
Contrast material administration did not change the metabolite ratios of MRS. Contrast administration would be useful in guiding voxel localization in MRS evaluation of intraaxial brain tumors. 相似文献107.
Bayindir Y Firat AK Kayabas U Alkan A Yetkin F Karakas HM Yologlu S 《Medical hypotheses》2012,79(1):43-46
Cutaneous anthrax, caused by Bacillus anthracis contacting the skin, is the most common form of human anthrax. Recent studies implicate the presence of additional, possibly toxin-related subtle changes, even in patients without neurological or radiological findings. In this study, the presence of subtle changes in cutaneous anthrax was investigated at the metabolite level using magnetic resonance spectroscopy. Study subjects were consisted of 10 patients with cutaneous anthrax without co-morbid disease and/or neurological findings, and 13 healthy controls. There were no statistical differences in age and gender between two groups. The diagnosis of cutaneous anthrax was based on medical history, presence of a typical cutaneous lesion, large gram positive bacilli on gram staining and/or positive culture for B. anthracis from cutaneous samples. Brain magnetic resonance imaging examination consisted of conventional imaging and single-voxel magnetic resonance spectroscopy. Magnetic resonance spectroscopy was performed by using point-resolved spectroscopy sequence (TR: 2000ms, TE: 136ms, 128 averages). Voxels of 20mm×20mm×20mm were placed in normal-appearing parietal white matter to detect metabolite levels. Cerebral metabolite peaks were measured in normal appearing parietal white matter. N-acetyl aspartate/creatine and choline/creatine ratios were calculated using standard analytical procedures. Patients and controls were not statistically different regarding parietal white matter N-acetyl aspartate/creatine ratios (p=0.902), a finding that implicates the conservation of neuronal and axonal integrity and neuronal functions. However, choline/creatine ratios were significantly higher in patient groups (p=0.001), a finding implicating an increased membrane turnover. In conclusion, these two findings point to a possibly anthrax toxins-related subtle inflammatory reaction of the central nervous system at the cellular level. 相似文献
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109.
Primary pulmonary artery leiomyosarcoma is a rare tumor that can be misdiagnosed as acute or chronic pulmonary thromboembolic disease. In this report, we present a case of a 58-year-old woman initially diagnosed with chronic thromboembolic pulmonary disease, but who was later found to have pulmonary artery leiomyosarcoma. A complete mass resection was performed surgically. The definitive pathologic examination was consistent with pulmonary artery leiomyosarcoma. Although the patient did not receive adjuvant therapy after the surgery, she had a good outcome and was free of disease 8 months after surgery. 相似文献
110.
Hakan Kiral Serdar Evman Cagatay Tezel Levent Alpay Tunc Lacin Volkan Baysungur Irfan Yalcinkaya 《Annals of thoracic and cardiovascular surgery》2015,21(2):125-131
Purpose: Massive hemoptysis is a life threatening situation with high mortality rates. Surgery is effective, however generally an avoided treatment. We report our experience with patients undergoing lung resection for life-threatening hemoptysis.Methods: Records of all surgically treated patients for hemoptysis between June 2009 and June 2012 were reviewed and analyzed retrospectively.Results: Anatomical resection was performed on 31 (15.3%) patients out of 203 patients referred to our intensive care unit for life-threatening hemoptysis. 25 (80.6%) were male and six (19.4%) were female; with mean age of 46.4 ± 13.7 (21–77). Pneumonectomy was performed in four (12.9%), lobectomy in 24 (77.4%), segmentectomy in two (6.5%) and bilobectomy in one case. Postoperative complications developed in eight (25.8%), and mortality was observed in two (6.5%) patients. Etiology was bronchiectasis in 13 (42.0%), tuberculosis in eight (25.8%), carcinoma in four (12.9%), aspergilloma in four (12.9%), hydatid cyst in one (3.2%) and lung abscess in one (3.2%) of the cases.Conclusions: Although lung resection in the treatment of massive hemoptysis is accompanied with high morbidity and mortality rates, surgery is the only permanent curative modality. Acceptable results can be achived in the company of a multidisciplinary approach, through avoidance of pneumonectomy and urgent surgery. 相似文献