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The interlead variability of QT interval in the 12-lead electrocardiogram, QT dispersion (QTd), has been shown to reflect dispersion of ventricular refractoriness and may provide a measure of arrhythmogenic potential in diabetic patients. QTd and heart rate corrected QTd (QTcd) were also proposed to be accurate predictors of cardiac death in patients with diabetes. In recent years, experimental and clinical evidence demonstrates that statins exert antiarrhythmic properties. Therefore, in the present study, we have examined whether simvastatin treatment has any effect on the QTd and QTcd in patients with diabetes mellitus. Sixty type 2 diabetic patients without known coronary artery disease and low-density lipoprotein cholesterol >100mg/dl and 30 age and sex-matched non-diabetic controls were included in a prospective study. Out of 60 diabetic patients, 30 were treated with simvastatin 40 mg/day for 1 year and the remaining 30 subjects were served as diabetic controls. No lipid lowering therapy was administered to the diabetic and the non-diabetic controls. QTd and QTcd of treated diabetics and the non-diabetic controls were measured at baseline, 6, 12 weeks and at 1 year. QTd and QTcd of the diabetic controls were obtained at baseline, 6 and 12 weeks. Both QTd and QTcd were significantly greater in patients with the diabetes than in the non-diabetic controls at baseline (52+/-13 ms vs. 41+/-12 ms, p<0.001 and 62+/-17 ms vs. 42+/-11 ms, p<0.001, respectively). Simvastatin therapy significantly decreased both QTd and QTcd at the end of first year compared to baseline (51+/-15 ms vs. 33+/-11 ms, p<0.001 and 60+/-18 ms vs. 38+/-12 ms, p<0.001, respectively). No significant change were found in QTd and QTcd in the non-diabetic (p=0.29 and p=0.87 by ANOVA, respectively) and in the diabetic controls (p=0.72 and p=0.57, by ANOVA, respectively). This study suggests for the first time that simvastatin treatment in diabetic patients with hyperlipidemia is associated with an improvement in the heterogeneity of cardiac repolarization. This may be one of the mechanisms for the reduction in clinical events reported in the survival studies with statins. Further prospective randomized studies are warranted to confirm our findings.  相似文献   
23.
Saddle nose reconstruction is based on the use of support grafts to manage aesthetic and functional problems. Bone (calvarial, iliac crest, costal, nasal hump, ulnar, and heterogeneous origin), cartilage (septal, costal, heterogeneous), and synthetic materials (silicon, silastic, polyethylene) were used as support grafts. Three patients have been included in this study to define the surgical management and long-term aesthetic and functional results of patients undergoing rhinoplasty with support grafts for a saddle nose deformity. Open rhinoplasty was employed. Both the lower turbinates were excised and the bone dissected from the soft tissues in two cases and in one case, only mucosa was removed. The amount of support needed was measured by using bone wax. The bone was used shaped in layers, according to the defect, and sutured to each other by vycril suture, and wrapped around by surgicell. The graft was then inserted in its place and fixed with external prolene sutures. Results were satisfactory in both function and aesthetics. Ten to 16-month follow-ups had no complications. Saddle nose surgery basically requires the use of a support graft to repair the nasal dorsum. A lower turbinate bone graft procedure has some advantages: it is cheap and safe, it is ready to use and not time-consuming, there is no donor area and no additional donor site morbidity, and it enlarges the airway and the passage to prevent nasal airway obstruction.  相似文献   
24.
PURPOSE: The aim of the study was to examine the effect of articaine hydrochloride (AH) on the healing of surgical wounds and to compare healing with that of lidocaine. MATERIALS AND METHODS: Forty rats were used in this study. The rats were randomly separated into 4 groups. Three groups were given 2% lidocaine, 4% AH, or injectable saline, and the fourth was a control group. Skin specimens underwent the breaking strength test (BST) and histologic examination at 1 week after the surgical procedure. The skin specimens of the rats were subjected to a pulling force of 10 mm/min across the incision line. The strength value at the moment of breaking in the tissue was expressed in Newtons. Histologic examination was performed as well, and wound healing was graded. RESULTS: Both the histologic grade and BST values in the lidocaine and AH groups were significantly lower than those of the control and saline groups (P <.01). Similarly, the histologic and BST values of the AH and lidocaine groups were statistically significant (P <.05, P <.001). Some necrotic regions were observed at the incision region in 2 samples from the AH group. CONCLUSION: The results of the study showed that AH is as safe a local anesthetic agent as lidocaine from the standpoint of wound response.  相似文献   
25.
Glutaric aciduria type I is an uncommon inborn error of metabolism. It is a serious disease, often with a fatal outcome. Magnetic resonance imaging findings and the clinical course of monozygotic twin females with glutaric aciduria type I who were admitted with acute encephalopathic crisis symptoms 3 days after immunization for poliovirus are presented in this report. Magnetic resonance imaging findings revealed hyperintensity in the putamen, head of the left caudate nucleus, and globus pallidus, periventricular white matter (on T2-weighted images), arachnoid cysts in bilateral temporal regions, and enlargement of the sylvian fissures. Glutaric aciduria type I should be included in the differential diagnosis of patients with acute encephalopathic crisis occurring shortly after poliovirus immunization. Typical magnetic resonance findings guide urinary organic acid analysis in these patients.  相似文献   
26.
BACKGROUND: Intraluminal brachytherapy has become an established treatment for major airway occlusion by relapsed or persistent inoperable endobronchial tumors. The aim of this study was to compare the palliation improvement pre- and post-radiotherapy. METHODS: The study group was 95 patients with the diagnosis of inoperable lung cancer who were eligible for HDR brachytherapy. Fiber-optic bronchoscopy was performed and the level and degree of endobronchial obstruction were estimated in terms of bronchial obstruction index. Endobronchial irradiation was delivered using remote HDR afterloading brachytherapy with iridium-192. Brachytherapy was delivered at weeks 1, 2 and 3 at 7.5 Gy per fraction or at weeks 1 and 2 at 10 Gy per fraction. All patients were evaluated at the beginning and at the third month of therapy. Using Speiser's symptomatic scoring criteria, the severity of symptoms (dyspnea, cough, hemoptysis and postobstructive pneumonia) was weighted. Bronchoscopic findings at the initial evaluation and at the third month were also scored. Surviving patients were followed up for a minimum of 3 months with a mean of 7.5 +/- 5.35 months (median: 6 months). RESULTS: All the symptoms and bronchial obstruction improved significantly after brachytherapy (P < 0.05). The most responding symptoms were dyspnea and hemoptysis. The factors determining the complete response were evaluated; age, staging, histological type, lesion localization and previous history of radiotherapy did not seem to determine the complete response (P > 0.05). CONCLUSIONS: All the symptoms and bronchial obstruction index seemed to improve after brachytherapy. However, it is difficult to predict the response before the therapy.  相似文献   
27.
The purpose of this study was to identify a reliable reference point for measuring anterior intermeniscal ligament thickness and to investigate the morphological characteristics of the ligament at its attachment site to anterior horns of both menisci by MRI. MRI was performed in 98 knees of randomly chosen patients. The anterior intermeniscal ligament was detected in 61 knees (62.2%). The average ligament length was 29.8 mm. Men had significantly longer anterior intermeniscal ligament than women patients (32.5 vs. 27.8 mm). The thickness of anterior intermeniscal ligaments at their attachment sites to menisci was usually less than 3 mm; a thickness of 3 mm or more at the attachment site to anterior horns of the meniscus was defined as "cordlike." It is suggested that the "cordlike" pattern is a variation of the anterior intermeniscal ligament's attachment characteristics, and that this might have a significant role in meniscal translations during knee motion, and also that the "cordlike" pattern could be clinically important with respect to its relationship to the anterior horn of medial meniscus. The attachment site of the ligament is a reliable reference point for measuring its thickness.  相似文献   
28.
Cerebral cortical development involves a complex cascade of events which are difficult to visualize in intact, living subjects. In this study, we apply diffusion tensor imaging (DTI) to the evaluation of cortical development in human infants ranging from 26 to 41 weeks gestational age (GA). Apparent diffusion of water in cortex is maximally anisotropic at 26 weeks GA and anisotropy values approach zero by 36 weeks GA. During this period, the major eigenvector of the diffusion tensor in cerebral cortex is oriented radially across the cortical plate, in accord with a predominately radial deployment of its neuronal constituents. Values for the rotationally averaged water diffusion coefficient increase between 26 and 32 weeks GA, then decrease thereafter. These changes in DTI parameters are specific to cerebral cortex and reflect changes in underlying cortical architecture and formation of neuronal connections. Because of its correlation with tissue microstructure and non-invasive nature, DTI offers unique insight into cortical development in preterm human newborns and, potentially, detection of derangements of its basic cytoarchiteture.  相似文献   
29.
BACKGROUND: Dual chamber pacemakers (single chamber pacing dual chamber sensing cardiac pacemaker (VDD) and dual chamber pacing and sensing cardiac pacemaker (DDD)) are being used frequently in children and adolescents. The aim of this study was to verify the safety and performance of the VDD and DDD pacing systems, and to evaluate the differences between two pacing modes with regard to atrial sensing and tracking functions. METHODS: In this study, we evaluated 14 patients with VDD pacing and 15 patients with DDD pacing between 1994 and 2000. In the patient group with VDD pacing, all had congenital or acquired atrioventricular (AV) block. In the patient group with DDD pacing, 11 had congenital or acquired AV block, three had sinus node dysfunction with AV conduction disturbance and one had idiopathic hypertrophic subaortic stenosis. Twenty-eight devices were implanted in the subpectoral area using the transvenous route. After implantation the atrial tracking capabilities of the pacing systems were analyzed by telemetry, Holter monitoring, and treadmill exercise testing. RESULTS: The mean age of patients in the VDD pacing group was younger. The percentage of congenital heart disease was higher in the DDD pacing group. There was no significant difference regarding fluoroscopy time during implantation and follow-up time between the two groups. During implantation, in the VDD pacing group the mean sensed atrial signal was 3.1 +/- 1.3 mV and this decreased to 1.37 +/- 0.68 mV (P < 0.05) during follow-up. This pattern was also observed in DDD group (3 +/- 2 mV vs 1.9 +/- 1.5 mV, P < 0.05). Although the P wave measurement at implantation did not differ between the two groups, it was significantly higher in the DDD pacing group at the last control. Three patients with VDD pacing were reprogrammed to VVI or single chamber pacing and sensing, rate adaptive cardiac pacemaker because of complete loss of AV synchrony. There was no atrial sensing problem in the DDD pacing group. During the follow-up, one patient with VDD pacing developed diaphragmatic stimulation and required lead revision. In one patient with DDD pacing, venous thrombosis occurred in the right subclavian vein and was treated with thrombolytic therapy. During treadmill exercise testing, in one patient with VDD and one patient with DDD pacing temporary failure of atrial sensing occurred. At 24 h Holter monitoring, intermittent loss of atrial sensing was documented in two patients with VDD pacing. CONCLUSIONS: Dual chamber pacing in children with DDD or VDD pacemakers is a suitable method for bradycardia treatment. Atrial sensing problems may occur in VDD pacemakers. Therefore, DDD pacing mode should be preferred whenever suitable for the patient to maintain the AV synchrony.  相似文献   
30.
We report a female newborn with Johanson–Blizzard syndrome associated with extreme intrauterine growth retardation, aged facial appearance, and atrial septal defect. Other features are microcephaly, prominent veins over the scalp, alopecia over the vertex, wide-open fontanelle, high forehead, antimongoloid slant, edematous eyelids, the absence of eyebrows and eyelashes, beaked nose with alae nasi, low-set ears, thin lips, and micrognathia. Investigations revealed deafness and congenital hypothyroidism. We believe that this association of severe intrauterine growth retardation and congenital heart disease represents the components of this syndrome.  相似文献   
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