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Ahmed Faeq Hussein Shaiful Jahari Hashim Ahmad Fazli Abdul Aziz Fakhrul Zaman Rokhani Wan Azizun Wan Adnan 《Journal of medical systems》2018,42(1):15
The non-stationary and multi-frequency nature of biomedical signal activities makes the use of time-frequency distributions (TFDs) for analysis inevitable. Time-frequency analysis provides simultaneous interpretations in both time and frequency domain enabling comprehensive explanation, presentation and interpretation of electrocardiogram (ECG) signals. The diversity of TFDs and specific properties for each type show the need to determine the best TFD for ECG analysis. In this study, a performance evaluation of five TFDs in term of ECG abnormality detection is presented. The detection criteria based on extracted features from most important ECG signal components (QRS) to detect normal and abnormal cases. This is achieved by estimating its energy concentration magnitude using the TFDs. The TFDs analyse ECG signals in one-minute interval instead of conventional time domain approach that analyses based on beat or frame containing several beats. The MIT-BIH normal sinus rhythm ECG database total records of 18 long-term ECG sampled at 128 Hz have been analysed. The tested TFDs include Dual-Tree Wavelet Transform, Spectrogram, Pseudo Wigner-Ville, Choi-Williams, and Born-Jordan. Each record is divided into one-minute slots, which is not considered previously, and analysed. The sample periods (slots) are randomly selected ten minutes interval for each record. This result with 99.44% detection accuracy for 15,735 ECG beats shows that Choi-Williams distribution is most reliable to be used for heart problem detection especially in automated systems that provide continuous monitoring for long time duration. 相似文献
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Muhammad Ihtisham Umar Mohd Zaini Asmawi Amirin Sadikun A. M. S. Abdul Majid Item Justin Atangwho 《Pharmaceutical biology》2014,52(11):1411-1422
Context: Azadirachta indica A. Juss. (Meliaceaes) leaves have been used traditionally to treat swelling and rheumatism in Indian cultures.Objective: To fractionate A. indica leaf extracts using bioactivity guided manner for identification of the active anti-inflammatory principles.Materials and methods: Polarity-gradient sequential extracts (petroleum ether, chloroform, methanol, and water) of A. indica leaves were screened for their anti-inflammatory potential using the carrageenan-induced rat paw edema model (1?g/kg). The chloroform extract was sequentially fractionated to obtain n-hexane (F-1), n-hexane-chloroform (F-2), and chloroform (F-3) fractions and their inhibitory effect on rat paw edema was evaluated (500?mg/kg). Inhibitory effect of F-2 on granuloma formation, plasma interleukin (IL-1), and tumor necrosis factor (TNF-α) was assessed at the doses of 100, 200, and 400?mg/kg using the cotton pellet assay in rats. Three sub-fractions (SF-1, SF-2, and SF-3) were obtained upon chromatography of F-2, and their inhibitory effect on cyclooxygenase was assessed at 200?µg/mL concentration. The sub-fractions were subjected to gas chromatography–mass spectrometry (GC-MS).Results: All the extracts showed significant anti-inflammatory effect; however, chloroform extract was the most effective against paw edema (53.25% inhibition). The three fractions of chloroform extract showed significant effect, while F-2 being the most potent (51.02%). F-2 demonstrated dose-dependent inhibition of granuloma and cytokines. Interestingly, all the sub-fractions of F-2 inhibited COX-1 and COX-2 with almost equal potential. GC-MS revealed that chemically the sub-fractions were totally different from each other.Discussion and conclusion: Anti-inflammatory effect of A. indica is a result of cumulative and synergistic effects of diversified constituents with varying polarities that collectively exert the effect via suppression of cyclo-oxygenases and cytokines (IL-1 and TNF-α). 相似文献
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Pei Lin Lua Nor Afiqah Ahmad Nasrulddin Abdul Manam Mohamad Mokhairi Makhtar Julaily Aida Jusoh Ramle Abdullah 《Alcoholism treatment quarterly》2018,36(3):399-418
Psychosocial profiles among a convenience sample of 37 Malay Muslim participants of Inabah program were measured using the Psychological Measure of Islamic Religiousness (PMIR). Data were analysed using SPSS 23.0. Positive relations with others emerged as the best-scored subscale whereas anger trait and depressed mood were minimal. Single and divorced respondents demonstrated significantly higher score for purpose in life. More favorable social desirability was reported by participants with no previous treatment. Less anger and depression were expressed by those not detained before. Essentially, psychosocial status of persons with substance use disorder undergoing Inabah program was moderate with some influences of sociodemographic factors. 相似文献
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Abdul H. Kandhro Virapong Prachayasittikul Chartchalerm Isarankura Na-Ayudhya 《Hemoglobin》2017,41(3):157-163
Among microcytic hypochromic anemias, the most common disorders are iron deficiency anemia and co-pathological conditions such as α- or β-thalassemia (α- or β-thal) traits. The aim of the present study was to determine the frequency and prevalence of iron deficiency anemia and α- or β-thal traits based on clinical laboratory data across different ethnic groups in five districts of Sindh Province, Pakistan. The present retrospective study analyzed 3 years (2012–2015) of encoded and unlinked clinical laboratory data, and identified 3030 microcytic hypochromic anemia cases. The data contained complete blood counts (CBCs) with smear morphology examinations, serum ferritin levels, and hemoglobin (Hb) electrophoreses. After reviewing the data, 994 confirmed subjects (iron deficiency anemia and α- and β-thal traits) were then selected for the present study. The prevalence of α- and β-thal traits was highest in Badin district (35.27%), while the prevalence of iron deficiency anemia was highest in Larkana district (30.73%). According to the ethnic-wise distribution, higher numbers of α- and β-thal trait cases were seen in the Sindhi ethnic group [375 (64.21%) and 283 (69.02%), respectively] than in the other ethnic groups. In addition, a higher distribution of β-thal trait cases was observed in the Sindhi ethnic group [n?=?327 (56%)] in α- and β-thal cases overall. Findings from the present study strongly suggested that screening is important not only for β-thal trait but also other traits as well. However, careful monitoring of CBC parameters, including red blood cell (RBC) indices and morphology, along with clinical findings are essential to diagnose carrier cases, especially in high prevalence areas. 相似文献
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Screening for subclinical subclavian artery stenosis before coronary artery bypass grafting: Should we do it?
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Ali Abdul Jabbar MD Justin Houston MD Mark Burket MD Zachary J. Il'Giovine MD Bal K. Srivastava MD Ajay Agarwal MD 《Echocardiography (Mount Kisco, N.Y.)》2017,34(6):928-933
Atherosclerotic subclavian artery disease is detected in about 5% of patients referred for coronary artery bypass (CABG) surgery. The internal mammary artery, a branch of the subclavian artery, is the most frequently utilized graft to restore coronary circulation because of its longevity. Stenosis or occlusion of the subclavian artery can cause retrograde blood flow in the ipsilateral internal mammary artery, known as “steal,” compromising coronary circulation supplied by the graft. Steal may be asymptomatic or may result in symptoms of myocardial ischemia. Symptomatic subclavian artery stenosis post bypass is referred to as coronary subclavian steal syndrome post‐CABG. The incidence is not well defined, and the benefits of screening patients referred for CABG are not known. Despite the various modalities available to detect subclavian artery stenosis, current guidelines fail to provide guidance about screening high‐risk patients for this entity. Detection of subclavian artery disease prior to CABG can reduce complications posed by post‐mammary artery graft cardiac ischemia. This review discusses the utility of preoperative subclavian artery screening prior to CABG. 相似文献
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