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Electrocardiogram (ECG) signal gives a lot of information on the physiology of heart. In reality, noise from various sources interfere with the ECG signal. To get the correct information on physiology of the heart, noise cancellation of the ECG signal is required. In this paper, the effectiveness of extended Kalman smoother (EKS) with the differential evolution (DE) technique for noise cancellation of the ECG signal is investigated. DE is used as an automatic parameter selection method for the selection of ten optimized components of the ECG signal, and those are used to create the ECG signal according to the real ECG signal. These parameters are used by the EKS for the development of the state equation and also for initialization of the parameters of EKS. EKS framework is used for denoising the ECG signal from the single channel. The effectiveness of proposed noise cancellation technique has been evaluated by adding white, colored Gaussian noise and real muscle artifact noise at different SNR to some visually clean ECG signals from the MIT-BIH arrhythmia database. The proposed noise cancellation technique of ECG signal shows better signal to noise ratio (SNR) improvement, lesser mean square error (MSE) and percent of distortion (PRD) compared to other well-known methods.  相似文献   
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Purpose/aim: To focus on current aspects of primary thyroid lymphoma (PTL), which is a rare clinical entity usually manifested by a rapidly growing mass in the neck that can cause pressure symptoms.

Materials and Methods: Relevant papers in PubMed published through June 2017 were selected to track updated information about PTL with an emphasis on diagnosis and novel therapeutic management.

Results: The most frequent cases include non-Hodgkin lymphoma derived from B-cells, mainly diffuse large B-cell lymphoma (DLBCL) followed by mucosa-associated lymphoid tissue (MALT) lymphoma or a mixed type. Other subtypes are less common. Lymphomas derived from T-cells and Hodgkin lymphomas are extremely rare. Hashimoto's autoimmune thyroiditis has been implicated as a risk factor for lymphoma. At the molecular level, the Wnt5a protein and its receptor Ror2 are involved in the course of the disease. Ultrasonography, fine needle aspiration (FNA) biopsy, and core or open biopsy combined with new diagnostic facilities contribute to an accurate diagnosis. An increased potential exists for a cure without the need for a radical surgical procedure. Modern chemoradiation therapy plus the monoclonal antibody rituximab, which acts against CD20, have limited the need for surgical interventions and provide an excellent outcome in most cases. However, some cases have resulted in treatment failure or recurrence.

Conclusions: A multidisciplinary approach must be used to define the management policy in each case. Future efforts by researchers are likely to be focused on the molecular level.  相似文献   

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Introduction

The fast track / ultra-fast-track protocols are techniques used to optimise the patient care process and a quick recovery after cardiac surgery. They are one of the mainstays of efficient practice. With their use, the length of hospital and intensive care unit (ICU) stays are reduced, with a direct impact on costs and the quality of the health service.

Objective

To compare the length of stay in the ICU, length of hospital stay, and post-operative mortality in ultra-fast-track extubated (uFTE) patients and those with conventional extubation (CE) after cardiac surgery.

Methods

Longitudinal, analytical, retrospective study was conducted, with the period between the time of surgery and discharge being included as the study period.

Results

A total of 396 patients older than 18 years who required cardiac surgery were included, of whom 207 patients had (uFTE) and 189 had CE. Although the groups were not comparable due to the statistical differences found, when performing the multivariate adjustment, uFTE maintained its statistical independence and was associated with lower cardiovascular morbidity, such as myocardial ischaemia (95% CI: 0.37-0.86; P = .01) and lower post-surgical vasopressor requirement (95% CI: 0.18-0.49; P < .01). No significant differences were found in the length of hospital stay, ICU stay, or post-operative mortality in the ICU.

Conclusion

Implementing the uFTE strategy, decreases cardiovascular morbidity and vasopressor requirement. The change to uFTE should be accompanied by changes in models and practices in patient recovery to standardised protocols. This study shows that uFTE did not reduce the length of ICU stay, hospital stay, or mortality.  相似文献   
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Background & Aims: Impaired message-structure mapping results in deficits in both sentence production and comprehension in aphasia. Structural priming has been shown to facilitate syntactic production for persons with aphasia (PWA). However, it remains unknown if structural priming is also effective in sentence comprehension. We examined if PWA show preserved and lasting structural priming effects during interpretation of syntactically ambiguous sentences and if the priming effects occur independently of or in conjunction with lexical (verb) information.

Methods & Procedures: Eighteen PWA and 20 healthy older adults (HOA) completed a written sentence-picture matching task involving the interpretation of prepositional phrases (PP; the chef is poking the solider with an umbrella) that were ambiguous between high (verb modifier) and low attachment (object noun modifier). Only one interpretation was possible for prime sentences, while both interpretations were possible for target sentences. In Experiment 1, the target was presented immediately after the prime (0-lag). In Experiment 2, two filler items intervened between the prime and the target (2-lag). Within each experiment, the verb was repeated for half of the prime-target pairs, while different verbs were used for the other half. Participants’ off-line picture matching choices and response times were measured.

Results: After reading a prime sentence with a particular interpretation, HOA and PWA tended to interpret an ambiguous PP in a target sentence in the same way and with faster response times. Importantly, both groups continued to show this priming effect over a lag (Experiment 2), although the effect was not as reliable in response times. However, neither group showed lexical (verb-specific) boost on priming, deviating from robust lexical boost seen in the young adults of prior studies.

Conclusions: PWA demonstrate abstract (lexically-independent) structural priming in the absence of a lexically-specific boost. Abstract priming is preserved in aphasia, effectively facilitating not only immediate but also longer-lasting structure-message mapping during sentence comprehension.  相似文献   

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