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In this paper, an intelligent system is presented for interpretation of the Doppler signals of the heart valve diseases based on the pattern recognition. This paper especially deals with combination of the feature extraction and classification from measured Doppler signal waveforms at the heart valve using the Doppler Ultrasound. Because of this, a wavelet packet neural network model developed by us is used. The model consists of two layers: wavelet and multi-layer perceptron. The wavelet layer is used for adaptive feature extraction in the time-frequency domain and is composed of wavelet packet decomposition and wavelet packet entropy. The multi-layer perceptron used for classification is a feed-forward neural network. The performance of the developed system has been evaluated in 215 samples. The test results showed that this system was effective in detecting Doppler heart sounds. The correct classification rate was about 94% for abnormal and normal subjects.  相似文献   
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Measles virus (MV) constitutes a principal cause of worldwide mortality, accounting for almost 1 million deaths annually. Although a live-attenuated vaccine protects against MV, vaccination efficiency of young infants is low because of interference by maternal antibodies. Parental concerns about vaccination safety further contribute to waning herd immunity in developed countries, resulting in recent MV outbreaks. The development of novel antivirals that close the vaccination gap in infants and silence viral outbreaks is thus highly desirable. We previously identified a microdomain in the MV fusion protein (F protein) that is structurally conserved in the paramyxovirus family and constitutes a promising target site for rationally designed antivirals. Here we report the template-based development of a small-molecule MV inhibitor, providing proof-of-concept for our approach. This lead compound specifically inhibits fusion and spread of live MV and MV glycoprotein-induced membrane fusion. The inhibitor induces negligible cytotoxicity and does not interfere with receptor binding or F protein biosynthesis or transport but prevents F protein-induced lipid mixing. Mutations in the postulated target site alter viral sensitivity to inhibition. In silico docking of the compound in this microdomain suggests a binding model that is experimentally corroborated by a structure-activity analysis of the compound and the inhibition profile of mutated F proteins. A second-generation compound designed on the basis of the interaction model shows a 200-fold increase in antiviral activity, creating the basis for novel MV therapeutics. This template-based design approach for MV may be applicable to other clinically relevant members of the paramyxovirus family.  相似文献   
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BackgroundThe information on electrocardiographic features of patients with coronavirus disease 2019 (COVID-19) is limited. Our aim was to determine if baseline electrocardiographic features of hospitalized COVID-19 patients are associated with markers of myocardial injury and clinical outcomes.MethodsIn this retrospective, single center cohort study, we included 223 hospitalized patients with laboratory-confirmed COVID-19. Clinical, electrocardiographic and laboratory data were collected and analyzed. Primary composite endpoint of mortality, need for invasive mechanical ventilation, or admission to the intensive care unit was assessed.ResultsForty patients (17.9%) reached the primary composite endpoint. Patients with the primary composite endpoint were more likely to have wide QRS complex (>120 ms) and lateral ST-T segment abnormality. The multivariable Cox regression showed increasing odds of the primary composite endpoint associated with acute respiratory distress syndrome (odds ratio 7.76, 95% CI 2.67–22.59; p < 0.001), acute cardiac injury (odds ratio 3.14, 95% CI 1.26–7.99; p = 0.016), high flow oxygen therapy (odds ratio 2.43, 95% CI 1.05–5.62; p = 0.037) and QRS duration longer than >120 ms (odds ratio 3.62, 95% CI 1.39–9.380; p = 0.008) Patients with a wide QRS complex (>120 ms) had significantly higher median level of troponin T and pro-BNP than those without it. Patients with abnormality of lateral ST-T segment had significantly higher median level of troponin T and pro-BNP than patients without.ConclusionsThe presence of QRS duration longer than 120 ms and lateral ST-T segment abnormality were associated with worse clinical outcomes and higher levels of myocardial injury biomarkers.  相似文献   
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Digestive Diseases and Sciences - Behçet’s disease (BD) and Crohn’s disease (CD) cannot be easily differentiated in young adults presenting with nonspecific gastrointestinal (GI)...  相似文献   
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We evaluated the short-term results of percutaneous excimer laser angioplasty in acute myocardial infarction. Of the 18 patients studied, 2 were female and 16 male with a mean age of 56.6 +/- 12.1 years. Thrombolysis in myocardial infarction grades 0, 1, and 2 flow was observed in 10, 5, and 3 cases, respectively, prior to the procedure. The degree of stenosis was 97.9% +/- 5.1%. The lesion was crossed with a laser catheter in all cases, using a mean number of 808 +/- 384 laser pulses. Type C dissection developed in only 1 case (6%). Except for this case, distal flow was grade 3 in all the patients. Following the procedure, ST segment resolution exceeding 70% was achieved in 14 cases (78%) within the first 90 minutes. The success rate of laser ablation was 94% (17 patients). Stent implantation was performed in all the cases. In conclusion, laser angioplasty is an effective and reliable treatment for acute myocardial infarction.  相似文献   
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A failure of a mitral valve repair, which includes the implantation of a mitral annuloplasty ring in the majority of cases, is associated with relevant mortality. Surgery is considered as the standard treatment for these patients. For patients who have an unacceptable high peri‐surgical risk a transcatheter valve‐in‐ring (TVIR) procedure might be an option. Isolated case reports and small case series report on the feasibility of a TVIR implantation in mitral position. We present a case where a 29‐mm Edwards Sapien valve was placed in a 32‐mm Carpentier Edwards ring. To our knowledge no valve has been implanted so far in this ring size and this is the first case where a veno‐arterial loop was used as guide rail for valve implantation and helped considerably to position the valve properly. © 2013 Wiley Periodicals, Inc.  相似文献   
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ABSTRACT: Chronic paranasal sinus disease is one of the most common causes of application to physicians in pediatric and adult patients. In the surgical treatment of these diseases, endoscopic sinus surgery is an application that is often done to increase the quality of the patient's life. On account of this, the anatomic variations in skull basement must be well known to avoid possible major complications that may occur during the operation.Recent developments in paranasal sinus surgery also enhanced the need for examining exhaustively the anatomy of this region and existing pathology. Superiority of computed tomography (CT) has an unquestionable importance for the evaluation of anatomic structure and pathology compared with conventional radiographs. A likely anatomic knowledge is needed for a safe surgery. Before the surgery, determining the anatomic variations makes the operation safer and increases the prospects, so we can prevent complications that may occur during the surgery.In this study, CT coronal sections of 300 patients who were admitted to the Department of Ear Nose Throat of Medical Faculty of Cumhuriyet University Research and Training Hospital between the dates December 2008 and January 2011 with complaints of nasal flow and postnasal drip were studied. According to coronal section CT examinations, the patients were divided into 2 groups. Group 1, with 156 cases (64%), showed mucosal changes, and in 144 cases (36%), no mucosal changes were established (group 2). In comparison between the sexes, in groups 1 and 2 females, significant difference was determined for other parameters except the average height of the ethmoid roof. In the comparison between the sexes, in groups 1 and 2 males, significant difference was determined for all parameters. The difference between these 2 rates was statistically significant.Keros types 1 and 2 cases were compared with the control group, and there was no statistically significant difference. Notwithstanding, at the comparison of the Keros type 3 with the control group, there was a statistically significant difference for all the parameters (maximum orbital height, the length of the middle concha, and the nasal wall).It seems to be important for us to know the average length of the peripheral anatomic structures to avoid serious complications that may occur during the operation. Careful preoperative review of paranasal sinus CT scans in patients undergoing sinus surgery seems to be the most important to prevent severe intraoperative complications.  相似文献   
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