Results 271 to 280 of about 112,312 (306)
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A continuous wave Doppler ultrasound method of recording fetal breathing in utero
Ultrasound in Medicine & Biology, 1979Abstract Intra-uterine fetal breathing can be measured using 2 MHz continuous wave Doppler ultrasound to monitor the fluctuations in venous return which are associated with the pressure changes induced by fetal breathing activity. This article describes the technique for locating the transducer on the maternal abdomen and the sounds that are heard ...
J D, Gough, E R, Poore
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Resonance based pre-processing method for eliminating artifacts in Doppler ultrasound signals
2017 25th Signal Processing and Communications Applications Conference (SIU), 2017Transcranial Doppler ultrasound has been successfully used in the evaluation of cerebrovascular pathologies such as stroke which is a very critical condition. Special micro-embolic signals, which are caused by the clots that can block blood vessels in brain, show themselves as an increase in reflected Doppler energy and can be used as the early ...
AYDIN, NİZAMETTİN, SERBES, GÖRKEM
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Usage of eigenvector methods to improve reliable classifier for Doppler ultrasound signals
Computers in Biology and Medicine, 2008A new approach based on the implementation of the automated diagnostic systems for Doppler ultrasound signals classification with the features extracted by eigenvector methods is presented. In practical applications of pattern recognition, there are often diverse features extracted from raw data which needs recognizing.
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Estimation of the Doppler ultrasound maximal umbilical waveform envelope: I. Estimation method
Ultrasound in Medicine & Biology, 2002We developed a parametric method of estimating the Doppler ultrasound (US) umbilical maximal flow waveform envelope that is robust to varying levels of signal-to-noise ratio (SNR). The method differs from previously proposed estimation algorithms in that it does not incorporate preliminary removal or reduction of noise; thus, avoiding potential ...
Doherty, D.A. +2 more
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Intraoperative doppler ultrasound: a reliable diagnostic method in insulinoma.
Hepato-gastroenterology, 2007A 44-year-old woman was admitted with obvious symptoms of hypoglycemia and Whipple's triad during a 6-month period. The glucose level was as low as 32 mg/dL and insulin/glucose ratio greater than 0.5 after fasting. Abdominal magnetic resonance imaging (MRI) studies revealed a pancreatic mass at the head, 2 cm in diameter that was not suggesting because
Hasan, Kalafat +3 more
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Improved method for cardiac output determination in man using ultrasound Doppler technique
Medical & Biological Engineering & Computing, 1990An existing ultrasound Doppler method for measuring cardiac output has been improved and refined, partly by locating the sampling volume higher up in the aorta while still using the aortic ring size as the effective transverse flow area. The basis for using this technique is the approximately rectangular systolic velocity profile in the aortic orifice ...
M, Eriksen, L, Walløe
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[Doppler ultrasound method in the study of vertigo syndrome].
Minerva medica, 1986Doppler C.W. technique represents a non-invasive, singular method to evaluate cerebrovascular diseases; therefore is now considered a screening method for vascular insufficiency, particularly in basilar artery insufficiency. Subclavian steal syndrome functional evaluation by Doppler C.W. is an important complement to angiographic studies.
V, Deambrogio, R, Bonardi
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Development of methods to analyse transcranial Doppler ultrasound signals recorded in microgravity
Medical & Biological Engineering & Computing, 1990During space flights, several clinical syndromes may be the result of changes in cerebral circulation. The purpose of the paper is to describe the development and initial evaluation of a system for recording, processing and displaying transcranial Doppler ultrasound (TCD) waveforms from the middle cerebral artery (MCA) in microgravity.
P J, Vaitkus +9 more
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A double beam doppler ultrasound method for quantitative blood flow velocity measurement
Ultrasound in Medicine & Biology, 1982A method for measuring the absolute blood flow velocity waveform is reported. Two independent beams of ultrasound illuminate a vessel simultaneously, producing complementary Doppler signals. The two Doppler frequency shift signals are processed by subtraction and addition at the receiver. The optimum probe position where blood flow velocity is detected
W, Wei-qi, Y, Lin-xin
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Thresholding-based Wavelet Packet Methods for Doppler Ultrasound Signal Denoising
2008Doppler ultrasound is widely used to diagnose vascular diseases because of its noninvasive advantages. Denoising of Doppler signals is necessary as a pre-processing for a high quality Doppler ultrasound system. Recently, there has been much work on denoising methods based on noise statistics and the spectrum distribution.
Jiangfeng Yu, Dong C. Liu
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