Search results for "Gate"
showing 10 items of 1811 documents
Two-dimensional echocardiographic evaluation of left ventricular ejection fraction by the ellipsoid single-plane algorithm: a reliable method for ass…
1995
The reliability of two-dimensional (2D) echocardiographic estimation of left ventricular ejection fraction (EF) is commonly recognized, but no satisfactory data are available about the accuracy of low or very low EF values determined by 2D echocardiography (ECHO-EF). The purpose of our study was to assess the reliability of low ECHO-EF values obtained using a simple time-economical algorithm such as the ellipsoid single-plane area-length method. Radionuclide angiography (RAD-EF) was taken as the standard of comparison. We studied 59 consecutive patients (31 women and 28 men) referred to our echocardiographic laboratory. Both 2D echocardiography and radionuclide angiography were blindly perf…
Surrogate data approaches to assess the significance of directed coherence: Application to EEG activity propagation
2009
This paper addresses the topic of evaluating the significance of frequency domain measures of causal coupling in multivariate time series through generation of surrogate data. The considered approaches are the traditional Fourier Transform (FT) algorithm and a new causal FT (CFT) algorithm for surrogate data generation. Both algorithms preserve the FT modulus of the original series; differences are in the phase relationships, that are completely destroyed for FT surrogates and imposed after switching off the link over the considered causal direction for CFT surrogates. The ability of the algorithms to assess causality in the frequency domain was tested using the directed coherence as discri…
Testing Frequency-Domain Causality in Multivariate Time Series
2010
We introduce a new hypothesis-testing framework, based on surrogate data generation, to assess in the frequency domain, the concept of causality among multivariate (MV) time series. The approach extends the traditional Fourier transform (FT) method for generating surrogate data in a MV process and adapts it to the specific issue of causality. It generates causal FT (CFT) surrogates with FT modulus taken from the original series, and FT phase taken from a set of series with causal interactions set to zero over the direction of interest and preserved over all other directions. Two different zero-setting procedures, acting on the parameters of a MV autoregressive (MVAR) model fitted on the ori…
The prognostic value of sentinel lymph node micrometastases in patients with invasive breast carcinoma
2016
The prognostic value of sentinel lymph node micrometastases in invasive breast cancer patients is still widely debated. Even if, in the absence of unequivocal guidelines, the axillary lynphadenectomy is not still performed in the routine clinical care of these patients.We have retrospectively analyzed 746 patients with operable invasive breast cancer and clinically negative axillary lymph nodes. These patients underwent conservative surgery or total mastectomy with sentinel lymph node biopsy. Patients with micrometastases in the sentinel lymph node treated with axillary dissection has been checked and the involvement of the remaining lymph nodes analyzed. Patients with micrometastases in th…
Electrophysiological findings of neuronal ceroid lipofuscinosis in heterozygotes.
1988
Nineteen obligate heterozygotes, 8 individuals at risk of being heterozygote, and 10 patients afflicted with four different forms of neuronal ceroid lipofuscinosis were examined electrophysiologically. The group of obligate heterozygotes was compared to age-matched control groups. Statistically significant differences were found between scotopic b-wave amplitudes, P-ERG amplitudes, and EOG light peaks of the obligate carriers of the juvenile type and the control subjects. The photopic L-ERGs and the latencies of the VEPs were mostly within the normal range. The findings represent the first evidence of functional ophthalmological changes in obligate carriers of neuronal ceroid lipofuscinosis…
Pneumococcus infections: Is the burden still as heavy?
2012
EA MERS CT3 Enjeu 3; International audience; The death rate of invasive pneumococcal infections decreased by 100 fold in one century. This tremendous improvement was due mainly to antibiotic use and multiple attempts at antipneumococcal vaccinations; thus, this was true only for developed countries. However, in France, the incidence has increased, over the last 10 years, in all age classes except for children vaccinated by the heptavalent pneumococcal conjugate vaccine. The incidence of these infections remains high, when associated to some risk factors such as HIV infection, malignant blood diseases, solid cancers, bronchial diseases, or alcohol abuse. The pneumococcal vaccine should be pr…
Time-Varying Surrogate Data to Assess Nonlinearity in Nonstationary Time Series: Application to Heart Rate Variability
2009
We propose a method to extend to time-varying (TV) systems the procedure for generating typical surrogate time series, in order to test the presence of nonlinear dynamics in potentially nonstationary signals. The method is based on fitting a TV autoregressive (AR) model to the original series and then regressing the model coefficients with random replacements of the model residuals to generate TV AR surrogate series. The proposed surrogate series were used in combination with a TV sample entropy (SE) discriminating statistic to assess nonlinearity in both simulated and experimental time series, in comparison with traditional time-invariant (TIV) surrogates combined with the TIV SE discrimin…
Comparison of concomitant outcome achieved with fresh and cryopreserved donor oocytes vitrified by the Cryotop method
2008
Objective To evaluate the outcome of oocyte vitrification using the Cryotop method, observed in an egg donation program by simultaneously evaluating embryos derived from vitrified and fresh oocytes coming from the same stimulated cycle. Design Cohort prospective randomized study. Setting Instituto Valenciano de Infertilidad (IVI) Valencia, Spain. Patient(s) Thirty oocyte donors and 30 recipients with informed consents. Intervention(s) Vitrification by the Cryotop method. Warming 1 hour after vitrification. Microinjection of surviving MII and fresh oocytes, evaluation of fertilization, embryo development, and clinical results. Main Outcome Measure(s) Survival, fertilization, and cleavage rat…
Effect of oestrogen/gestagen replacement therapy on liver enzymes in patients with Ullrich-Turner syndrome.
1995
The absence of breast development and the prevention of osteoporosis in Ullrich-Turner syndrome (UTS) require oestrogen/gestagen substitution therapy. In 8 out of 35 (23%) patients with UTS treated with conjugated equine oestrogens and cyclically with norethisterone acetate, the serum liver enzymes increased to conspicuous levels (AST 35; 20-73 U/l, ALT 92; 37-141 U/l, GGT 77; 25-227 U/l, [median; min-max]). These findings were compared with those in 41 tall girls who received a six-fold larger dose of conjugated equine oestrogens for the reduction of final height. None of these 41 girls showed abnormal serum liver enzyme levels. The conspicuous rise in serum liver enzyme levels occurred in…
The accuracy of sentinel lymph node biopsy in the treatment of multicentric invasive breast cancer using a subareolar injection of tracer.
2008
BACKGROUND: The aim of this study was to evaluate the feasibility and the accuracy of sentinel lymph node biopsy in multicentric breast cancer (MBC) performed by means of a subareolar (SA) injection of both 99Tc-labeled human albumin colloid and lymphazurin. METHODS: Between January 2002 and October 2007, 34 patients with MBC with clinically negative axilla underwent sentinel lymph node biopsy (SLNB) followed by total axillary node dissection (AD). Overall successful identification rate of SLN was 100%; there were no false negatives and overall accuracy rate was 100%. RESULTS: The mean number of sentinel lymph nodes (SLNs) identified was 1.8 +/- 0.88 (range = 1-4); the mean number of axilla…