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81.
Fatemeh Safara Shyamala Doraisamy Azreen Azman Azrul Jantan Asri Ranga Abdullah Ramaiah 《Computers in biology and medicine》2013
Wavelet packet transform decomposes a signal into a set of orthonormal bases (nodes) and provides opportunities to select an appropriate set of these bases for feature extraction. In this paper, multi-level basis selection (MLBS) is proposed to preserve the most informative bases of a wavelet packet decomposition tree through removing less informative bases by applying three exclusion criteria: frequency range, noise frequency, and energy threshold. MLBS achieved an accuracy of 97.56% for classifying normal heart sound, aortic stenosis, mitral regurgitation, and aortic regurgitation. MLBS is a promising basis selection to be suggested for signals with a small range of frequencies. 相似文献
82.
Daisuke Tajima Takuji Nakamura Fumio Ichinose Nobuhiko Okamoto Yuko Tomonoh Keiko Uda Rie Furukawa Katsuya Tashiro Muneaki Matsuo 《Brain & development》2021,43(3):482-485
Paroxysmal abnormal eye movement in early infancy is one of the initial symptoms of glucose transporter 1 deficiency syndrome (GLUT1DS). We describe four early infants with transient hypoglycorrhachia presenting with abnormal eye movements. Their symptoms disappeared after the introduction of a ketogenic diet (KD), and their development was normal. Since no variants in SLC2A1 were detected, the CSF-to-blood glucose ratios (C/B) were re-examined, and within normal range. None of the four patients displayed recurrent symptoms after withdrawal from the KD. Because long-term KD has potential adverse effects and could affect the quality of life of patients and their families, re-examination of CSF glucose during late infancy should be considered in the case of absence of the SLC2A1 pathogenic variant. 相似文献
83.
This paper presents an improvement of the subtraction procedure for interference cancellation in ECG. In contrast to the well-known hardware and software filters, the procedure does not affect the signal frequency components around the rated powerline frequency. Originally, the procedure was developed for multiplicity between the sampling rate and the interference frequency. We analysed and improved the procedure structure in cases of non-multiple sampling, introducing a set of specially designed filters. Thus the implementation of the subtraction procedure is extended to almost all possible cases of sampling rate and interference frequency variation. The procedure has been adapted for online implementation. The research was initially carried out in a MATLAB environment. Further, programmes have been written in C?+?+ language for digital signal processors and personal computers. The results obtained with real ECG signals show high efficiency of the interference cancellation. 相似文献
84.
85.
Madhuri Arvind Patel 《Journal of obstetrics and gynaecology of India》2015,65(6):372-375
Scar ectopic pregnancy is the rarest form of ectopic pregnancy and has been increasingly diagnosed all over the world. This is a life-threatening form of abnormal implantation of embryo within the myometrium and fibrous tissues in a previous scar on the uterus, especially following caesarean section. With the increasing rate of caesarean section, there is a substantial increase in this condition with better understanding of this disease. The early and accurate diagnosis with timely management can prevent pregnancy complications such as haemorrhage, uterine rupture and can preserve fertility. 相似文献
86.
Recent theories emphasize the dynamic aspects of emotions. However, the physiological measures and the methodological approaches that can capture the dynamics of emotions are underdeveloped. In the current study, we investigated whether moment‐to‐moment changes in autonomic nervous system (ANS) activity are reliably associated with the unfolding of emotional experience. We obtained cardiovascular and electrodermal signals from participants while they viewed emotional movies. We found that the ANS signals were temporally aligned across individuals, indicating a reliable stimulus‐driven response. The degree of response reliability was associated with the emotional time line of the movie. Finally, individual differences in ANS response reliability were strongly correlated with the subjective emotional responses. The current research offers a methodological approach for studying physiological responses during dynamic emotional situations. 相似文献
87.
预防接种异常反应的处理是一项政策性、技术性很强的工作,一定要及时调查谨慎处理,防止事态不必要的扩大。为规范预防接种异常反应监测,查明预防接种异常反应发生的原因,制定预防接种服务措施,杜绝或减少因禁忌症掌握不严或告知不详细等所造成的预防接种异常反应,2007年3月对维西县1例疑似预防接种异常反应死亡报告进行了及时的调查处置。死亡婴儿已由其家人自行水葬处理,综合分析调查情况,应认定为照看不当导致的婴儿窒息死亡。 相似文献
88.
目的 研究糖耐量异常对冠心病患者氧化应激和血管内皮功能、心率变异性的影响及阿卡波糖的干预作用。方法 选择伴糖耐量异常的冠心病患者60例为糖耐量异常组,糖耐量正常的冠心病患者30例为糖耐量正常组。所有研究对象均进行血液生物化学指标检查,包括空腹血糖、餐后2 h血糖、总胆固醇、甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、丙二醛(MDA)、红细胞超氧化物歧化酶(SOD)、一氧化氮(NO)、内皮素1(ET-1)的检测。24 h动态心电图监测心率变异性,并比较以上指标。糖耐量异常的冠心病患者(糖耐量异常组)随机分为对照组30例与治疗组30例,对照组给予冠心病的常规治疗,治疗组在冠心病常规治疗的基础上加用阿卡波糖50 mg,每天3次,共观察6个月;6个月后两组复查以上检测项目,并比较两组治疗前后及两组治疗后上述指标的变化,分析以上指标的相关性。结果 糖耐量异常组较糖耐量正常组MDA、ET-1水平明显增高,SOD、NO水平明显降低(P<0.05)。心率变异性指标:糖耐量异常组SDNN、SDNN5、SDANN较糖耐量正常组明显减低(P<0.05),糖耐量异常组TRIA、PNN50、rMSSD与糖耐量正常组比较差别无统计学意义。阿卡波糖治疗6个月后,治疗组治疗后与治疗前及对照组治疗后比较MDA、ET-1水平明显下降,SOD、NO水平明显增高,差别有统计学意义。治疗组治疗后SDNN、SDNN5、SDANN较治疗前及对照组治疗后明显增高(P<0.05),治疗组TRIA、PNN50、rMSSD治疗前后无明显差异,对照组各项指标治疗前后无明显差异。治疗前后心率变异性指标SDNN的变化值与治疗前后MDA、SOD、NO变化值呈正相关(r=0.512,r=0.368,r=0.420,P<0.05)。结论 合并糖耐量异常的冠心病患者有更严重的血管内皮功能损伤及自主神经功能异常,氧化应激参与了上述过程。阿卡波糖治疗后氧化应激反应减轻,血管内皮功能及自主神经功能明显改善;阿卡波糖对合并糖耐量异常的冠心病患者的血管内皮功能、自主神经功能损伤有治疗作用。 相似文献
89.
【摘要】 目的 探讨940例肝功能异常患儿临床特征,为临床早期诊断、及时治疗提供参考依据。 方法 回顾性分析2015年1月~2018年9月来自云南地区以不明原因肝功能异常收治入院的940例患儿的临床资料,包括临床表现、病因、肝功能及临床疗效等。 结果 肝功能异常与年龄相关,以0~12个月婴儿为高发年龄群(706例,75.11%)。肝功能异常程度以轻度异常(534例,56.81%)最多见,其中以0~6个月小婴儿轻度肝功能异常最多见(P<0.05)。肝功能异常病因以感染为主(543例,57.76%,其中病毒感染353例,细菌感染190例),其次为其他不明原因(290例,30.85%)。经治疗88.40%的患儿治愈或好转。结论 应重视儿童肝功能常规检查,特别是对于12个月以内的小婴儿。肝功能异常病因明确者应及时采取对因治疗;不明原因者需进一步完善遗传、代谢疾病基因筛查甚至行有创操作等检查以明确病因,早期干预,合理治疗。 相似文献
90.
Studer V Bobin J Chahid M Mousavi HS Candes E Dahan M 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(26):E1679-E1687
The mathematical theory of compressed sensing (CS) asserts that one can acquire signals from measurements whose rate is much lower than the total bandwidth. Whereas the CS theory is now well developed, challenges concerning hardware implementations of CS-based acquisition devices--especially in optics--have only started being addressed. This paper presents an implementation of compressive sensing in fluorescence microscopy and its applications to biomedical imaging. Our CS microscope combines a dynamic structured wide-field illumination and a fast and sensitive single-point fluorescence detection to enable reconstructions of images of fluorescent beads, cells, and tissues with undersampling ratios (between the number of pixels and number of measurements) up to 32. We further demonstrate a hyperspectral mode and record images with 128 spectral channels and undersampling ratios up to 64, illustrating the potential benefits of CS acquisition for higher-dimensional signals, which typically exhibits extreme redundancy. Altogether, our results emphasize the interest of CS schemes for acquisition at a significantly reduced rate and point to some remaining challenges for CS fluorescence microscopy. 相似文献