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51.
Background and Aim:  Hepatic alveolar echinococcosis (HAE) involves both the vascular and biliary structures of the liver. Endoscopic retrograde cholangiopancreatography (ERCP) is said to be an alternative for the diagnosis and treatment of biliary complications of HAE. We present here our experience with ERCP in HAE.
Methods:  We followed 13 patients who underwent ERCP for the treatment of biliary complications of HAE in the endoscopy unit of our clinic at Ataturk University School of Medicine, Erzurum between January 2002 and June 2008.
Results:  Eight men and five women were followed up. Mean age was 43.2 (24–64 years). All patients had non-resectable HAE. Indications for ERCP were biliary fistula in seven patients, obstructive jaundice in five patients and cholangitis in one patient. Endoscopic sphincterotomy (ES) was carried out in 12 patients, and in one patient with biliary leakage, a stent was inserted into the right hepatic branch. ERCP findings were dilated common bile duct, irregular narrowing and distortion of the common bile duct and common hepatic duct, communication with the cystic cavity or biliocutaneous fistula and complete disappearance of the biliary tree above the level of the common hepatic duct or hepatic bifurcation. In patients with biliary leakage, biliary drainage decreased only in two patients after ERCP and in patients with obstructive jaundice, the high bilirubin levels decreased in only one patient.
Conclusion:  ERCP showed structural changes of the external biliary tract and ES has a limited effect on these changes and stents can be used in selected cases.  相似文献   
52.

Objective

Many applications such as biomedical signals require selecting a subset of the input features in order to represent the whole set of features. A feature selection algorithm has recently been proposed as a new approach for feature subset selection.

Methods

Feature selection process using ant colony optimization (ACO) for 6 channel pre-treatment electroencephalogram (EEG) data from theta and delta frequency bands is combined with back propagation neural network (BPNN) classification method for 147 major depressive disorder (MDD) subjects.

Results

BPNN classified R subjects with 91.83% overall accuracy and 95.55% subjects detection sensitivity. Area under ROC curve (AUC) value after feature selection increased from 0.8531 to 0.911. The features selected by the optimization algorithm were Fp1, Fp2, F7, F8, F3 for theta frequency band and eliminated 7 features from 12 to 5 feature subset.

Conclusion

ACO feature selection algorithm improves the classification accuracy of BPNN. Using other feature selection algorithms or classifiers to compare the performance for each approach is important to underline the validity and versatility of the designed combination.  相似文献   
53.
Risk factors for recurrent shunt-related cerebrospinal fluid (CSF) infections were analyzed. A total of 58 children were treated for initial shunt infections (ISI): all children were treated with antibiotics and CSF drainage, either by removal of the shunt system and insertion of an external ventricular drainage (EVD) catheter (44 children, 75.9%) or by externalization of the existing ventricular catheter (14 children, 24.1%). Recurrent shunt infections (RSI) were detected in 15 children: nine had been treated with shunt removal and insertion of a new EVD catheter and six had been treated with externalization of the existing ventricular catheter. There was a statistically significant increase in the number of RSI in children treated with externalization of the existing ventricular catheter. Thus, to reduce the risk of RSI, total shunt removal and insertion of a new EVD catheter is preferred.  相似文献   
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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   
56.
The acute effects of 50 mg of sildenafil on tear functions were evaluated in 12 impotent patients. Mean tear breakup time, cotton thread, and Schirmer I tests were 19.42±6.45 s, 13.92±6.63 mm, and 16.58±12.19 mm, respectively before sildenafil and 20.33±10.40 s, 10.92±6.14 mm, and 18.08±12.36 mm, respectively, 1 hour after sildenafil. The results suggest that sildenafil does not adversely affect tear functions. The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes unlabeled, unapproved, or investigative products or devices.  相似文献   
57.
Clones of multipotent mouse tetratocarcinoma stem cells, presumptively heterozygous at the adenine phosphoribosyltransferase (APRT) locus (EC 2.4.2.7), were selected for partial resistance to the purine analog 2,6-diaminopurine (DAP). All had approximately 50% APRT activity as compared to the parental line and were found to segregate homozygous deficient cells at a high frequency (10–2). Homozygous deficient cells were isolated from one of the heterozygotes and were found to fall into a single class characterized by residual activity and the segregation of revertants at an equally high frequency. The revertants in turn gave rise to full mutants at comparably high frequencies. Chromosomal changes detectable with the light microscope were not associated with these transitions. Physical characterization of the APRT enzymes derived from mutant, revertant, and wild-type cells did not reveal any differences. We conclude that the reversible switching between heterozygosity and homozygosity is attributable to some form of gene inactivation and reactivation rather than to classical mutational events.  相似文献   
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60.
BACKGROUND: The management of the apical multiple muscular ventricular septal defects (VSDs) remains still controversial. There are various surgical techniques and approaches for closure of "Swiss-cheese" VSDs. In this study, we report the outcome of multiple muscular VSDs repair, using the septal obliteration technique. METHODS: We used the septal obliteration technique in five "Swiss-cheese" ventricular septal defects cases through right atriotomy. Four of the cases had isolated multiple VSDs. One case also had an aortic arch interruption type A, which was repaired prior to cardiopulmonary bypass. Their ages varied between 43 days and 6 years. RESULTS: We did not experience any mortality or serious morbidity. Tracheostomy was required in one patient. There was no important residual shunt in postoperative period, except a minimal shunt in one case. CONCLUSION: The closure technique of "Swiss-cheese" trabecular multiple VSDs using a large single patch was not troubling. Transatrial approach prevented postoperative problems of ventricular incision. Using a large needle with a large pledgett is the key, which provides deep tissue penetration to avoid residual shunt.  相似文献   
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