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91.
Portosystemic collaterals are the natural consequence of portal hypertension. These collaterals can occur anywhere in the gastrointestinal tract. Apart from the usual sites, they can develop in some unusual and rare locations. In this report, imaging findings of an unusual venous collateral pathway between spleen and left subclavian vein in a 30-year-old female patient with cirrhosis and portal hypertension are presented.  相似文献   
92.
This study determined whether prolonged QRS duration (QRSd; > or =120 ms) is an independent predictor of low cardiac output syndrome (LCOS) in patients with low left ventricular (LV) ejection fraction (EF) who underwent isolated coronary artery bypass grafting (CABG). Abnormal LV systolic function places patients at greater risk for developing LCOS after isolated CABG. In patients with this form of ventricular function impairment, prolonged QRSd is associated with adverse hemodynamic effects. Clinical, operative, and outcome data from 190 consecutive patients with LVEF <50% who underwent isolated CABG (mean 62 +/- 9 years of age) were retrospectively analyzed. For all patients, preoperative QRSd was determined. LCOS was the primary outcome investigated. Fifty-seven patients (30%) developed LCOS. Compared with the subgroup without LCOS, the subgroup with this syndrome had significantly larger proportions of patients with LVEF <30% and prolonged QRSd. In addition, the group that developed LCOS had a longer mean QRSd (117 +/- 25 vs 102 +/- 17 ms, respectively, p = 0.00003) and a significantly higher frequency of adverse postoperative outcomes. Hospital stay was significantly longer in the subgroup with LCOS than in the subgroup without. Multivariate logistic regression analysis identified prolonged QRSd as the most significant predictor of LCOS. LVEF <30%, diuretic therapy, and preoperative risk score (European System for Cardiac Operative Risk Evaluation) were also identified as independent predictors of LCOS. In conclusion, in patients with impaired LV systolic function, prolonged QRSd is a highly significant predictor of LCOS development after isolated CABG.  相似文献   
93.
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   
94.
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96.
Noncompaction of ventricular myocardium: A study of twelve patients   总被引:5,自引:0,他引:5  
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   
97.
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   
98.
Tularemia outbreaks have occurred in various regions of Turkey in recent years. In this study, clinical (145 patients) and laboratory (97 patients) features of patients with oropharyngeal tularemia were evaluated during the tularemia outbreak in the district of Gölcük in Kocaeli, Turkey. We analyzed the risk factors for therapeutic failure and prolonged recovery time, and compared the efficacy of three antibiotic groups, namely aminoglycoside, tetracycline and quinolone. The most common physical sign and laboratory findings in patients were lymphadenopathy (LAP) and increased erythrocyte sedimentation rate, respectively. Treatment failure was observed in 55 of the 145 (38%) patients during one‐year follow‐up and the most successful results were obtained in the quinolone group. It was determined that antimicrobial therapy initiated 14 days after onset of symptoms was a statistically significiant risk factor, reducing the success rate (p=0.0001, OR=13.10, 95% CI=5.69–30.15) and prolonging the recovery period (p=0.001, OR=3.23, 95% CI=1.63–6.40) in oropharyngeal tularemia cases. These results suggest that antimicrobial treatment should be started early, and quinolones such as moxifloxacin and ciprofloxacin seem to be new alternatives in the treatment of oropharyngeal tularemia.  相似文献   
99.

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   
100.
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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