Search results for "Algorithms"
showing 10 items of 1716 documents
In Vitro Percutaneous Penetration of Acyclovir from Solvent Systems and Carbopol 971-P Hydrogels: Influence of Propylene Glycol
2005
The mechanism underlying propylene glycol (PG) effects on acyclovir (ACV) penetration through human epidermis were studied. Solvent systems and Carbopol gels containing increasing percentage of PG (from 0% to 70%, w/w) were used. Viscosity studies of both vehicles were carried out to characterise the influence of rheological behaviour. In solvent systems skin permeation values of ACV increase as the concentration of PG increase yielding a maximum enhancement ratio (ER = 10) for 70% PG. The release rate of ACV from gels was determined. Higuchi's model was used to estimate the apparent diffusion coefficient of the drug. These values show a decrease as the content of PG in the vehicle increase…
Mixed predictability and cross-validation to assess non-linear Granger causality in short cardiovascular variability series
2006
A method to evaluate the direction and strength of causal interactions in bivariate cardiovascular and cardiorespiratory series is presented. The method is based on quantifying self and mixed predictability of the two series using nearest-neighbour local linear approximation. It returns two causal coupling indexes measuring the relative improvement in predictability along direct and reverse directions, and a directionality index indicating the preferential direction of interaction. The method was implemented through a cross-validation approach that allowed quantification of directionality without constraining the embedding of the series, and fully exploited the available data to maximise th…
Long-term outcome prediction by clinicopathological risk classification algorithms in node-negative breast cancer--comparison between Adjuvant!, St G…
2009
Background: Defining risk categories in breast cancer is of considerable clinical significance. We have developed a novel risk classification algorithm and compared its prognostic utility to the Web-based tool Adjuvant! and to the St Gallen risk classification. Patients and methods: After a median follow-up of 10 years, we retrospectively analyzed 410 consecutive node-negative breast cancer patients who had not received adjuvant systemic therapy. High risk was defined by any of the following criteria: (i) age 2 cm. All patients were also characterized using Adjuvant! and the St Gallen 2007 risk categories. We analyzed disease-free survival (DFS) and overall survival (OS). Results: The Node-…
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…
Integrated pre-surgical diagnostic algorithm to define extent of disease in cervical cancer
2020
ObjectivesSurvival of patients with cervical cancer is strongly associated with the local extent of the primary disease. The aim of the study was to develop an integrated diagnostic algorithm, including ultrasonography (USG), magnetic resonance imaging (MRI), and examination under anesthesia, to define the local extent of disease in patients with newly diagnosed cervical cancer.MethodsPatients with biopsy proven cervical cancer who underwent primary surgery from January 2013 to December 2018 in four participating centers were recruited. Patients who underwent USG, MRI, and examination under anesthesia prior to surgery were included in the study. Those for whom complete data were not availab…
Neurological vertigo in the emergency room in pediatric and adult age: systematic literature review and proposal for a diagnostic algorithm.
2022
AbstractNeurological vertigo is a common symptom in children and adults presenting to the emergency department (ED) and its evaluation may be challenging, requiring often the intervention of different medical specialties. When vertigo is associated with other specific symptoms or signs, a differential diagnosis may be easier. Conversely, if the patient exhibits isolated vertigo, the diagnostic approach becomes complex and only through a detailed history, a complete physical examination and specific tests the clinician can reach the correct diagnosis. Approach to vertigo in ED is considerably different in children and adults due to the differences in incidence and prevalence of the various c…
Low estradiol-to-testosterone ratio is associated with oligo-anovulatory cycles and atherogenic lipidic pattern in women with polycystic ovary syndro…
2010
The estradiol-to-testosterone (E2/T) ratio has been investigated in different diseases but few in vivo data are available with regard to its role in women with ovary syndrome (PCOS). The aim of this study was to evaluate the role of the E2/T ratio in the ovulatory function and metabolic pattern in such women.We retrospectively evaluated hyperandrogenemia, clinical hyperandrogenism, ovarian morphology, hypothalamo-hypophyseal axis and metabolic syndrome parameters in a cohort of 202 consecutive women affected by PCOS. An oral glucose tolerance test measured areas under the curve for insulin (AUC(2hIRI)), for glucose (AUC(2hglucose)), and the HOMA-IR and Matsuda index of insulin resistance we…
Bed rest after embryo transfer negatively affects in vitro fertilization: a randomized controlled clinical trial.
2013
Objective To evaluate the influence of 10 minutes of bed rest after ET on the achievement of a live-born infant (LBI) in patients undergoing IVF treatment with oocyte donation (OD). Design Prospective, randomized, parallel assignment, controlled trial. Setting Private IVF center. Patient(s) A total of 240 patients undergoing a first IVF cycle with OD in our center. Intervention(s) Ten minutes of bed rest after ET or no bed rest, that is, allowing patients to ambulate immediately after the ET. Main Outcome Measure(s) The primary outcome was LBI rate per randomized patient. Secondary outcomes were implantation rate and biochemical and clinical miscarriage rates. Result(s) LBI rates (56.7% vs.…
Comparison of the rates of joint arthroplasty in patients with severe factor VIII and IX deficiency: an index of different clinical severity of the 2…
2009
AbstractData from the Italian Hemophilia Centres were collected to perform a retrospective survey of joint arthroplasty in patients with severe hemophilia. Twenty-nine of 49 hemophilia centers reported that 328 of the 347 operations were carried out in 253 patients with severe hemophilia A (HA) and 19 in 15 patients with severe hemophilia B (HB). When results were normalized to the whole Italian hemophilia population (1770 severe HA and 319 severe HB), patients with HA had a 3-fold higher risk of undergoing joint arthroplasty (odds ratio [OR], 3.38; 95% confidence interval [CI], 1.97-5.77; P < .001). These results were confirmed after adjustment for age, HIV, hepatitis C virus (HCV), and…
Characterisation of indeterminate focal breast lesions on grey-scale ultrasound: role of ultrasound elastography.
2011
PURPOSE: This study was undertaken to evaluate the role of ultrasound (US) elastography in characterising focal breast lesions classified as indeterminate on B-mode US. MATERIALS AND METHODS: Eighty-four focal breast lesions, 64 benign and 20 malignant (mean diameter, 15.1 mm), detected but not characterised on B-mode US in 72 women, Breast Imaging Reporting and Data System (BI-RADS) US category 3 (n=56) or category 4 (n=28), were studied with US elastography and classified in consensus by two radiologists according to a five-point colour scale. Sensitivity, specificity and positive and negative predictive values (PPV and NPV) of US elastography compared with conventional US were calculated…