Search results for "Algorithms"
showing 10 items of 1716 documents
Semi-automated retinal vessel analysis in nonmydriatic fundus photography.
2013
Purpose Funduscopic assessment of the retinal vessels may be used to assess the health status of microcirculation and as a component in the evaluation of cardiovascular risk factors. Typically, the evaluation is restricted to morphological appreciation without strict quantification. Our purpose was to develop and validate a software tool for semi-automated quantitative analysis of retinal vasculature in nonmydriatic fundus photography. Methods matlab software was used to develop a semi-automated image recognition and analysis tool for the determination of the arterial–venous (A/V) ratio in the central vessel equivalent on 45° digital fundus photographs. Validity and reproducibility of the r…
Differential association of default mode network connectivity and rumination in healthy individuals and remitted MDD patients
2016
Rumination is associated with increased default-mode network (DMN) activity and functional connectivity (FC) in depressed and healthy individuals. In this study, we sought to examine the relationship between self-reported rumination and resting-state FC in the DMN and cognitive control networks in 25 remitted depressed patients and 25 matched healthy controls using independent component and seed-based analyses. We also explored potential group differences in the global pattern of resting-state FC. Healthy subjects with increased levels of rumination exhibited increased anterior DMN connectivity with the posterior DMN and the dorsal attention network and low connectivity within the anterior …
Screening for gastric cancer using exhaled breath samples.
2019
Abstract Background The aim was to derive a breath-based classifier for gastric cancer using a nanomaterial-based sensor array, and to validate it in a large screening population. Methods A new training algorithm for the diagnosis of gastric cancer was derived from previous breath samples from patients with gastric cancer and healthy controls in a clinical setting, and validated in a blinded manner in a screening population. Results The training algorithm was derived using breath samples from 99 patients with gastric cancer and 342 healthy controls, and validated in a population of 726 people. The calculated training set algorithm had 82 per cent sensitivity, 78 per cent specificity and 79 …
Electrical impedance spectroscopy as a potential adjunct diagnostic tool for cutaneous melanoma.
2012
Background Previous studies have shown statistically significant differences in electrical impedance between various cutaneous lesions. Electrical impedance spectroscopy (EIS) may therefore be able to aid clinicians in differentiating between benign and malignant skin lesions. Objectives The aim of the study was to develop a classification algorithm to distinguish between melanoma and benign lesions of the skin with a sensitivity of at least 98% and a specificity approximately 20 per cent higher than the diagnostic accuracy of dermatologists. Patients/Methods A total of 1300 lesions were collected in a multicentre, prospective, non-randomized clinical trial from 19 centres around Europe. Al…
Causal cross-spectral analysis of heart rate and blood pressure variability for describing the impairment of the cardiovascular control in neurally m…
2006
A causal approach to the calculation of coherence and transfer function between systolic pressure (SP) and RR interval variability was applied in eight patients and eight control subjects during prolonged tilt test for investigating the impairment of cardiovascular control related to neurally mediated syncope. The causal analysis showed a depressed baroreflex regulation in resting patients, with reduced gain and increased latency from SP to RR, and a drop of the baroreflex coupling immediately before syncope. These findings, which were not elicited by traditional cross-spectral analysis, strongly suggest the use of the causal approach for the study of syncope mechanisms. © 2006 IEEE.
Comparison of the sympathetic skin response and continuous wave Doppler sonography of the radial artery.
1999
The value of neurophysiological tests of the autonomic nerve system is limited. One of the clinically most commonly applied test is the skin sudomotor response, frequently referred to as 'sympathetic skin response' (SSR). However, the SSR is a more qualitative than quantitative evaluation technique. Continuous wave (cw) Doppler sonography of the radial artery may be an alternative quantitative approach. We studied 41 age matched volunteers (23 female, 18 male; 16-82 years (mean age 53 years)). The stimulus was a loud and unexpected acoustic signal, alternatively a cough. SSR evaluation included the latency of onset, the duration and the amplitude of the response. Doppler evaluation also inc…
Rapid Musculoskeletal Magnetic Resonance Imaging Using Integrated Parallel Acquisition Techniques (IPAT) - Initial Experiences
2003
Purpose To investigate the feasibility of using multiple receiver coil elements for time saving integrated parallel imaging techniques (iPAT) in traumatic musculoskeletal disorders. Material and methods 6 patients with traumatic derangements of the knee, ankle and hip underwent MR imaging at 1.5 T. For signal detection of the knee and ankle, we used a 6-channel body array coil that was placed around the joints, for hip imaging two 4-channel body array coils and two elements of the spine array coil were combined for signal detection. All patients were investigated with a standard imaging protocol that mainly consisted of different turbo spin-echo sequences (PD-, T (2)-weighted TSE with and w…
GnRH agonist administration at the time of implantation does not improve pregnancy outcome in intrauterine insemination cycles: a randomized controll…
2009
Objective To assess whether GnRH agonist administration in the luteal phase improves pregnancy outcome in intrauterine insemination (IUI) cycles. Design Single-center, randomized, single-blind, placebo-controlled trial. Setting University-affiliated infertility clinic, between February 2005 and December 2007. Patient(s) Three hundred forty-four women undergoing IUI owing to mild to moderate male factor or donor sperm indication. Intervention(s) Random administration to either a single subcutaneous injection of 0.1 mg triptorelin (group A; n = 172) 8 days after hCG administration, or solvent only (group B; n=172) at the same time. Main Outcome Measure(s) Pregnancy rate was the primary outcom…
Predictive role of capillaroscopic skin ulcer risk index in systemic sclerosis: A multicentre validation study
2012
IntroductionThe early detection of systemic sclerosis (SSc) patients at high risk of developing digital ulcers could allow preventive treatment, with a reduction of morbidity and social costs. In 2009, a quantitative score, the capillaroscopic skin ulcer risk index (CSURI), calculated according to the formula ‘D×M/N2’, was proposed, which was highly predictive of the appearance of scleroderma digital ulcers within 3 months of capillaroscopic evaluation.ObjectivesThis multicentre study aims to validate the predictive value and reproducibility of CSURI in a large population of SSc patients.MethodsCSURI was analysed in 229 unselected SSc patients by nailfold videocapillaroscopy (NVC). All pati…
Effects of endurance training only versus same-session combined endurance and strength training on physical performance and serum hormone concentrati…
2014
This study investigated the effects of endurance training only (E, n = 14) and same-session combined training, when strength training is repeatedly preceded by endurance loading (endurance and strength training (E+S), n = 13) on endurance (1000-m running time during incremental field test) and strength performance (1-repetition maximum (1RM) in dynamic leg press), basal serum hormone concentrations, and endurance loading-induced force and hormone responses in recreationally endurance-trained men. E was identical in the 2 groups and consisted of steady-state and interval running, 4–6 times per week for 24 weeks. E+S performed additional mixed-maximal and explosive-strength training (2 times…