Search results for "methods"
showing 10 items of 4526 documents
Influence of roasting and different brewing processes on ochratoxin A content in coffee determined by high-performance liquid chromatography-fluoresc…
2008
A rapid and reliable procedure has been developed for the determination of ochratoxin A (OTA) in green and roasted coffee. The method consists of extraction of the sample with methanol-5% aqueous sodium hydrogen carbonate/1% PEG8000 (20:80), followed by immunoaffinity column (IAC) clean-up and, finally, high-performance liquid chromatography (HPLC) determination with fluorimetric detection. Mean recoveries for green and roasted coffee spiked at different levels ranging from 94 and 105% were obtained. The limit of determination (S/N = 3) was 0.032 ng g(-1) and the precision (within-laboratory relative standard deviation) was 6%. The method described has been used to assess the influence of r…
Caliper navigation for craniotomy planning of convexity targets.
2021
Introduction A technique to localize a radiological target on the head convexity fast and with acceptable precision is sufficient for surgeries of superficial intracranial lesions, and of help in the setting of emergency surgery, computer navigation breakdown, limited resources and education. We present a caliper technique based on fundamental geometry, with inexpensive and globally available tools (conventional CT or MRI image viewer, calculator, caliper). Methods The distances of the radiological target from two landmarks (nasion and porus acusticus externus) are assessed with an image viewer and Pythagoras’ theorem. The two distances are then marked around the landmarks onto the head of…
Sample pretreatment techniques for oligopeptide analysis from natural sources
2008
The analysis of oligopeptides in samples of food, tissues, and body fluids attracts considerable attention. The complexity of such samples requires efficient sample preparation (i.e., concentration and cleanup) procedures to remove interfering endogenous compounds and inorganic or organic salts. The methods of sample pretreatment that enable effective and selective isolation and/or preconcentration of oligopeptides from complex sample matrices have been reviewed. In each case, examples of application were presented and discussed, taking into account selectivity, enrichment, method automation, cleanup, and environmental aspects of the developed methods.
Predicting the environmental suitability for onchocerciasis in Africa as an aid to elimination planning
2021
Recent evidence suggests that, in some foci, elimination of onchocerciasis from Africa may be feasible with mass drug administration (MDA) of ivermectin. To achieve continental elimination of transmission, mapping surveys will need to be conducted across all implementation units (IUs) for which endemicity status is currently unknown. Using boosted regression tree models with optimised hyperparameter selection, we estimated environmental suitability for onchocerciasis at the 5 × 5-km resolution across Africa. In order to classify IUs that include locations that are environmentally suitable, we used receiver operating characteristic (ROC) analysis to identify an optimal threshold for suitabil…
Clinical assessment of patients with advanced non-small-cell lung cancer eligible for second-line chemotherapy
2010
Purpose: Knowledge of prognostic factors for advanced non-small-cell lung cancer (NSCLC) patients eligible for second-line treatment is scarce. The aim of this study was to assess the prognostic role of a number of routinely collected clinical variables and to provide a summary index to discriminate patients according to probability of survival.Methods: individual data from nine randomised trials of second-line treatment in advanced NSCLC were analysed. Primary end-point was overall survival (OS). Cox model, stratified by trial, was used for multivariate analyses, and a prognostic index was provided and validated according to an internal/external procedure.Results: Out of 1239 patients, 119…
Biopsy vs. brushing: comparison of two sampling methods for the detection of HPV-DNA in squamous cell carcinoma of the oral cavity
2012
Background: HR HPV infection was proposed as aetiological factor of oral squamous cell carcinomas (OSCC). HPV frequency in OSCC is highly variable, due to the discrepancy in oral sampling procedures, HPV testing methods and inclusion criteria regarding tumour site (strictly oral cavity vs. nearby structures). Our aim was to compare HPV DNA frequency and type-specific distribution in paired cytological and histological samples of SCC strictly located in oral cavity. The correlation between HPV detection rate by each method of sampling and demographical, behavioural and clinical-pathological variables was also examined. Patients and methods: HPV DNA was detected in brushed cells and formalin-…
Alternative Methods for Skin Sensitisation Testing
1996
Radiomic analysis reveals DCE-MRI features for prediction of molecular subtypes of breast cancer.
2017
The purpose of this study was to investigate the role of features derived from breast dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and to incorporated clinical information to predict the molecular subtypes of breast cancer. In particular, 60 breast cancers with the following four molecular subtypes were analyzed: luminal A, luminal B, human epidermal growth factor receptor-2 (HER2)-over-expressing and basal-like. The breast region was segmented and the suspicious tumor was depicted on sequentially scanned MR images from each case. In total, 90 features were obtained, including 88 imaging features related to morphology and texture as well as dynamic features from tumor and …
The lifelong risk of metachronous colorectal cancer justifies long-term colonoscopic follow-up.
2007
The aim of this study was to calculate the risk of metachronous colorectal cancers, to specify their characteristics and potential risk factors in a well-defined French population over a 27-year period.The 10,801 patients who had colorectal cancers totalled 61,879 person-years of follow-up. The actuarial method was used to obtain crude metachronous colorectal cancer rates. Standardised incidence ratios (SIRs) were calculated.The cumulative rate of metachronous colorectal cancer was 1.8% at 5 years, 3.4% at 10 years and 7.2% at 20 years. The incidence of metachronous colorectal cancer following a first colorectal cancer was higher than expected (SIR: 1.5 [1.3-1.7] p0.001). It remained greate…
Centre characteristics and procedure-related factors have an impact on outcomes of allogeneic transplantation for patients with CLL: a retrospective …
2017
Abstract Introduction:Even in the era of novel targeted therapies for the treatment of Chronic Lymphocytic Leukemia (CLL) patients, such as BTK, PI3K and BCL2 inhibitors, allogeneic hematopoietic stem cell transplantations (alloHCT) will remain an important treatment option for a subset of patients with very high risk CLL. The current study focused on the impact of center and procedure-related factors on outcomes after alloHCT, taking into account the impact of patient- and disease-related risk factors. Patients and Methods:Data of 684 CLL patients who received a first alloHCT between 2000 and 2011 were analyzed. Their data were collected as part of the EBMT CLL Data Quality Initiative. Out…