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Increasing incidence of Crohn’s disease (CD) in the Western world has made its accurate diagnosis an important medical challenge. The current reference standard for diagnosis, colonoscopy, is time-consuming and invasive while magnetic resonance imaging (MRI) has emerged as the preferred noninvasive procedure over colonoscopy. Current MRI approaches assess rate of contrast enhancement and bowel wall thickness, and rely on extensive manual segmentation for accurate analysis. We propose a supervised learning method for the identification and localization of regions in abdominal magnetic resonance images that have been affected by CD. Low-level features like intensity and texture are used with shape asymmetry information to distinguish between diseased and normal regions. Particular emphasis is laid on a novel entropy-based shape asymmetry method and higher-order statistics like skewness and kurtosis. Multi-scale feature extraction renders the method robust. Experiments on real patient data show that our features achieve a high level of accuracy and perform better than two competing methods.  相似文献   
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Kaṣāya or decoction is an Ayurvedic dosage form, prescribed based on the stage of the disease according to the principles of Ayurveda. This dosage form is traditionally prepared fresh and consumed on the same day but for the sake of convenience; the process of preparation has been modified so that it can be stored with longer shelf life, easy availability and produced in large quantities. There is a need to understand the implications of this modification in terms of chemical changes. This work attempted to check the phytochemical profile of both freshly prepared decoction and commercially available decoction with reference to some analytical parameters like pH, total soluble solids, phenols, alkaloids, potassium and to assess the changes in the thin layer chromatography profiling of the decoction. The results showed that phenols and potassium are found to be two fold higher in freshly prepared decoction, compared to commercially available decoction diluted to dosage in practice (1:4 ratio). However, the total alkaloid content was found to be approximately ten fold higher in commercially available decoction. It was observed that the thin layer chromatography profile of decoctions was extracted into petroleum ether and chloroform was similar and consistent with different batches though the bands in commercially available decoction were slightly more intense compared to freshly prepared decoction. The total soluble solids in commercially available decoction were four times higher than freshly prepared decoction. The study reveals that there are differences in the phytochemical profiles of the freshly prepared decoction and commercially available decoction of the same formulation. However, the significance of these differences can be determined only by further clinical studies. On the other hand, the study lends support to the practice of diluting the commercially available decoction to make it equivalent to freshly prepared decoction.  相似文献   
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Autoimmune hemolytic anaemia (AIHA) has traditionally been classified based on the temperature sensitivity of the autoagglutinins as warm (WAIHA), cold (CAIHA) and mixed type. Autoagglutinin may be of IgG or IgM type. The present prospective study was conducted to evaluate the profile of clinical picture, severity of haemolysis, treatment response of steroid. This study on patients of adult primary AIHA was conducted by taking complete history followed by detail physical examination. Laboratory investigations were performed to establish haemolytic anaemia and to assess severity of haemolysis. Immunehematological work up including blood grouping, direct antiglobulin test (DAT), IAT, antibody screening, adsorption elution was performed to diagnose type of AIHA. All cases were followed up to assess the response to prednisolone. All the data were collected and analysed by SPSS 19. Out of 62 primary AIHA cases, female were affected more than male (41:21). WAIHA is most common type (42, 67.8%) followed by mixed (20.9%) and cold AIHA (11.3%). Severity of haemolysis showed significant correlation with the DAT strength and not with type of AIHA. (P < 0.05) On oral prednisolone, 22 cases attended complete remission, while relapse, drug dependency and partial remission was achieved in 13, 9, 3 cases respectively. Severity of haemolysis in AIHA is directly related with DAT strength. WAIHA is most common type and can be managed with oral prednisolone (cr 45.2%), without red cell transfusion in most of cases. Mixed type AIHA cases were presented mostly with severe haemolysis, with minimum therapeutic response to prednisolone and maximum relapse/drug dependency.  相似文献   
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Background: Morphologic identification of ectopic P‐waves from surface ECGs can be challenging, particularly when the P‐wave is buried in the QRST wave complex. Because ECGs are often available on paper and not digitally, we developed a method of subtracting the T‐wave from the buried P‐wave complex on paper ECGs. Methods: To validate our system, an atrial extrastimulus was introduced during and following the T‐wave. The ECGs were scanned and then transformed from an image format to a digital format. A computer algorithm digitally subtracted a QRST with no buried P‐wave from one with a buried P‐wave, thus resulting in an extracted P‐wave. The extracted P‐waves were compared to the nonburied P‐wave by determining correlation coefficients and by visual grading by two independent reviewers. Results: Visual grading comparing the buried P‐wave with the exposed paced P‐wave was 94%. The median correlation coefficient was 85%. Conclusions: An ectopic atrial P‐wave obscured by a coincident QRST wave complex can be accurately derived from printed ECG using this PC‐based system. Addition of this technique to the existing methods may aid in the localization and ablation of ectopic atrial foci.  相似文献   
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Patients with mitral valve disease and extreme enlargement of the left atrium usually exhibit significant decrease in chamber size following corrective mitral valve surgery. We describe a patient in whom extreme right and left atrial enlargement developed, and progressed following mitral valve replacement, with no evidence of prosthetic valve malfunction or tricuspid valve disease.  相似文献   
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Maladaptive daydreaming (MD) is an immersive fantasy activity that leads to distress and socio-occupational dysfunction. MD has many features suggestive of behavioural addiction, but research exploring the phenomenology of this clinical construct is limited. MD has also been purported to be a maladaptive strategy to cope with distress, but often leads to uncontrollable absorption in fantasy world, social withdrawal and neglected aspects of everyday life. In this paper, we report the case of a 16-year-old boy who developed internet gaming disorder and MD after experiencing cyberbullying from his peers. The patient engaged in vivid, fanciful imagery that lasted for hours, leading to social dysfunction and academic deterioration. Baseline assessment revealed a Maladaptive Daydreaming Scale-16 score of 65 (cut-off 50) and an Internet Gaming Test-20 score of 86 (cut-off 71). The patient was managed primarily with psychological intervention. The therapy focused on behaviour modification and cognitive restructuring. Patients in clinical setting should be questioned about MD when presenting with excessive use of technology or other forms of behavioural addictions. Further studies are necessary to determine the biopsychosocial factors of MD and its correlates. There is also a need to study treatment and management approaches for treating MD.  相似文献   
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