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41.
Since segmentation of magnetic resonance images is one of the most important initial steps in brain magnetic resonance image processing, success in this part has a great influence on the quality of outcomes of subsequent steps. In the past few decades, numerous methods have been introduced for classification of such images, but typically they perform well only on a specific subset of images, do not generalize well to other image sets, and have poor computational performance. In this study, we provided a method for segmentation of magnetic resonance images of the brain that despite its simplicity has a high accuracy. We compare the performance of our proposed algorithm with similar evolutionary algorithms on a pixel-by-pixel basis. Our algorithm is tested across varying sets of magnetic resonance images and demonstrates high speed and accuracy. It should be noted that in initial steps, the algorithm is computationally intensive requiring a large number of calculations; however, in subsequent steps of the search process, the number is reduced with the segmentation focused only in the target area.  相似文献   
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B‐type natriuretic peptide (BNP) levels have been shown to predict ventricular arrhythmia (VA) and sudden death in patients with heart failure. We sought to determine whether BNP levels before left ventricular assist device (LVAD) implantation can predict VA post LVAD implantation in advanced heart failure patients. We conducted a retrospective study consisting of patients who underwent LVAD implantation in our institution during the period of May 2009–March 2013. The study was limited to patients receiving a HeartMate II or HeartWare LVAD. Acute myocardial infarction patients were excluded. We compared between the patients who developed VA within 15 days post LVAD implantation to the patients without VA. A total of 85 patients underwent LVAD implantation during the study period. Eleven patients were excluded (five acute MI, four without BNP measurements, and two discharged earlier than 13 days post LVAD implantation). The incidence of VA was 31%, with 91% ventricular tachycardia (VT) and 9% ventricular fibrillation. BNP remained the single most powerful predictor of VA even after adjustment for other borderline significant factors in a multivariate logistic regression model (P < 0.05). BNP levels are a strong predictor of VA post LVAD implantation, surpassing previously described risk factors such as age and VT in the past.  相似文献   
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AIM: The healthy ranges for serum alanine aminotransferase (ALT) levels are less well studied. The aim of this study was to define the upper limit of normal (ULN) for serum ALT levels, and to assess factors associated with serum ALT activity in apparently healthy blood donors. METHODS: A total of 1,939 blood donors were included. ALT measurements were performed for all cases using the same laboratory method. Healthy ranges for ALT levels were computed from the population at the lowest risk for liver disease. Univariate and multivariate analyses were performed to evaluate associations between clinical factors and ALT levels. RESULTS: Serum ALT activity was independently associated with body mass index (BMI) and male gender, but not associated with age. Association of ALT with BMI was more prominent in males than in females. Upper limit of normal for non-overweight women (BMI of less than 25) was 34 U/L, and for non-overweight men was 40 U/L. CONCLUSION: Serum ALT is strongly associated with sex and BMI. The normal range of ALT should be defined for male and female separately.  相似文献   
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AIM:The healthy ranges for serum alanine aminotransferase (ALT) levels are less well studied. The aim of this study was to define the upper limit of normal (ULN) for serum ALT levels, and to assess factors associated with serum ALT activity in apparently healthy blood donors.METHODS: A total of 1 939 blood donors were included.ALT measurements were performed for all cases using the same laboratory method. Healthy ranges for ALT levels were computed from the population at the lowest risk for liver disease. Univariate and multivariate analyses were performed to evaluate associations between clinical factors and ALT levels.RESULTS: Serum ALT activity was independently associated with body mass index (BMI) and male gender, but not associated with age. Association of ALT with BMI was more prominent in males than in females. Upper limit of normal for non-overweight women (BMI of less than 25) was 34 U/L,and for non-overweight men was 40 U/L.CONCLUSION: Serum ALT is strongly associated with sex and BMI. The normal range of ALT should be defined for male and female separately.  相似文献   
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OBJECTIVE: The purpose of this double-blind, placebo-controlled study was to evaluate the safety, clinical efficacy and tolerability of imiquimod (2%) in cream to cure external genital warts in males. METHODS: Preselected male patients (n=60) ranging between 18 and 50 years of age (mean 24.2) harbouring 558 lesions (mean 9.3) with clinical, histopathological and polymerase chain reaction (PCR) confirmed diagnosis of human papilloma virus (HPV) infection were randomized to two parallel groups. Each patient was allocated a precoded 25g tube, and instructions on how to apply the trial medication to their lesions at home once daily for three consecutive days per week (max. 12 application in 4 weeks). To evaluate the safety, clinical efficacy and tolerance, patients were exa-mined on a weekly basis. Cure was defined as the total elimination of treated warts with PCR, and Southern blot hybridization confirmed negative HPV DNA. RESULTS: By the end of the treatment, 40% (24/60) patients and 49.8% (278/558) warts were cured. Breaking the code revealed that imiquimod cream had cured 70% (21/30) patients and 86.8% of warts, while placebo healed three subjects and 28 warts (P=0.0001). Eleven patients (18.3%), predominantly in the imiquimod cream group, experienced mild to moderate, non-objective, drug-related side effects with no dropouts. The study was followed up for 18 months from the first day of the treatment, and among the 26 cured patients, one in the imiquimod cream group and two in the placebo had a relapse after 14 months. CONCLUSION: The study demonstrated that 2% imiquimod in cream with mild non-objective side effects is safe, tolerable and significantly more effective than placebo in curing external genital warts in males.  相似文献   
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Uterine lymphoma is rare and tends to be misdiagnosed due to lack of specific radiologic features. Few reports have been published on the sonographic characteristics of uterine lymphoma. We present a case report of uterine lymphoma manifested by a fast growing uterus and describe the sonographic findings. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound, 43 :59–63, 2015  相似文献   
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BACKGROUND: Recurrent abdominal pain (RAP) affects many children, especially those affected by beta-thalassaemia major. The role of Helicobacter pylori is still unclear in children with RAP. OBJECTIVES: The aim of the present study was the comparison of beta-thalassaemia major patients and normal controls with RAP in H. pylori infection. The factors influencing H. pylori prevalence were also investigated. METHODS: A series of 50 beta-thalassaemia major cases (30 female, 20 male; aged 6-25 years) and 50 age-matched and sex-matched controls, both presenting with RAP, were recruited during a period of 18 months. The study participants were obtained through a multistage random sampling method among those that met Apley's criteria. All the patients and controls had undergone diagnostic oesophagogastroduodenoscopy with biopsy. H. pylori infection was confirmed by two histopathological examinations on an endoscopy sample and a rapid urease test. RESULTS: H. pylori infection in thalassaemic patients was more common than in controls [34/50 (68%) versus 30/50 (60%)], but this higher frequency was not statistically significant. A clear relationship was found between the prevalence of H. pylori and age, duration of transfusion/chelation programmes, pain duration and splenectomy. In contrast, H. pylori did not correlate with abdominal pain characteristics, blood group, serum ferritin level and pathology of the upper gastrointestinal tract. The most frequent endoscopy abnormality was gastritis (72%). Nausea and heartburn were the leading associated symptoms. CONCLUSION: The high prevalence of H. pylori infection suggests that H. pylori should be remembered as a probable cause of RAP in beta-thalassaemia major patients.  相似文献   
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