Search results for "Reference value"

Multicenter validation of the magnetic resonance t2* technique for segmental and global quantification of myocardial iron

2009

Purpose To assess the transferability of the magnetic resonance imaging (MRI) multislice multiecho T2* technique for global and segmental measurement of iron overload in thalassemia patients. Materials and Methods Multiecho T2* sequences were installed on six MRI scanners. Five healthy subjects (n = 30) were scanned at each site; five thalassemia major (TM) patients were scanned at the reference site and were rescanned locally (n = 25) within 1 month. T2* images were analyzed using previously validated software. Results T2* values of healthy subjects showed intersite homogeneity. On TM patients, for global heart T2* values the correlation coefficient was 0.97, coefficients of variation (CoV…

Plasma lipid, apolipoprotein and Lp(a) levels in elderly normolipidemic women: Relationships with coronary heart disease and longevity

1995

The relation between plasma lipids and coronary heart disease (CHD) in the elderly is still debated, as well as the proposed role of lipoproteins as markers of longevity. In this study both normolipidemic elderly and middle-aged women with CHD showed higher triglycerides and apolipoprotein B levels and lower high-density lipoprotein (HDL)-cholesterol and apolipoprotein A-I levels in comparison with age-matched subjects without CHD. In the middle-aged group, hypertension and HDL-cholesterol levels and, in the elderly group, only HDL-cholesterol levels were independently associated with CHD. No significant difference was found between a group of healthy centenarians and elderly and middle-age…

Cortical responses of infants with and without a genetic risk for dyslexia

1999

We studied auditory event-related potentials (ERP) in newborns and 6-month-old infants, about half of whom had a familial risk for dyslexia. Syllables varying in vowel duration were presented in an oddball paradigm, in which ERPs to deviating stimuli are assumed to reflect automatic change detection in the brain. The ERPs of newborns had slow positive deflections typical of their age, but significant stimulus and group effects were found only by the age of 6 months. In both groups, the responses to the deviant /ka/ were more positive than those to the standard /kaa/ stimuli, contrary to the findings of adult ERPs to duration changes. The results also suggested differences in brain activatio…

Prostacyclin receptor desensitization is a reversible phenomenon in human platelets.

1997

Background Long-term exposure of platelets to endogenous or exogenous prostacyclin or its analogues might result in desensitization of the platelet prostacyclin receptor in vitro and in vivo accompanied by a loss in receptor density on the platelet surface and a reduced sensitivity toward the inhibitory effects of prostacyclins. However, the reversibility of this process in platelets has not yet been investigated. Methods and Results Human platelets desensitized by the chemically stable prostacyclin analogue iloprost showed a significant reduction in [ 3 H]-iloprost binding sites that was reversed by saponin permeabilization. This indicates functionally active internalized prostacyclin rec…

Application of solid-phase microextraction combined with derivatization to the determination of amphetamines by liquid chromatography

2004

This work evaluates the utility of solid-phase microextraction (SPME) in the analysis of amphetamines by liquid chromatography (LC) after chemical derivatization of the analytes. Two approaches have been tested and compared, SPME followed by on-fiber derivatization of the extracted amphetamines, and solution derivatization followed by SPME of the derivatives formed. Both methods have been applied to measure amphetamine (AP), methamphetamine (MA), and 3,4-methylenedioxymethamphetamine (MDMA), using the fluorogenic reagent 9-fluorenylmethyl chloroformate (FMOC) and carbowax-templated resin (CW-TR)-coated fibers. Data on the application of the proposed methods for the analysis of different kin…

A preliminary study on the stability of benzodiazepines in blood and plasma stored at 4 degrees C.

1997

An approach to determine the stability of benzodiazepines and some of their metabolites (n = 13) by means of a routinely applied gas chromatographic method using electron capture detection was made in this preliminary study. Validation data of the method are given. Spiked blood and plasma samples were stored at 4 degrees C and analysed at selected times up to 240 days. The concentrations of all analytes had decreased to at least 60% of the original levels at the end of the observation period. A clear pattern of breakdown could not be established. The data obtained suggest that results from long-term stored samples should be interpreted cautiously. Further investigations concerning the stabi…

Base Excess and Strong Ion Difference: Clinical Limitations Related to Inaccuracy

2004

Skinfold Sum: Reference Values for Top Athletes

2012

Las determinaciones de los pliegues subcutaneos de diferentes zonas corporales son utilizadas ocasionalmente en ecuaciones predictivas para calcular la masa grasa. Este es un parametro critico que condiciona el optimo rendimiento deportivo. No existen valores de referencia de pliegues subcutaneos en atletas de elite. Por tanto, el principal objetivo de este estudio es presentar valores de referencia de pliegues subcutaneos de una amplia poblacion de atletas. Los pliegues tricipital, subescapular, suprailiaco, abdominal, muslo y pierna fueron medidos de acuerdo a la normativa ISAK (Sociedad Internacional para el Avance de la Cineantropometria) en 2500 atletas. La suma de los seis pliegues as…

C4 Alpha-Chain Reference Typing Report

1990

Previously it was shown that C4A and C4B alpha-chains after separation on SDS-PAGE can provide valuable information on presence and absence, as well as the number of C4A and C4B genes expressed in an individual. All samples submitted for C4 reference typing were also subjected to C4 alpha-chain separation; the results were included in the Final C4 Reference Typing List [Complement Inflamm 1990;7:193-212]. In addition, in selected cases with assumed 'reversed antigenicity', Western blots of C4 alpha-chains with monoclonal anti-C4A and B antibodies were obtained. As a result, subtypic differences of C4B allotypes were detected by the comparison of monoclonal antibodies 1217 and 1228.

Background levels and baseline values of available heavy metals in Mediterranean greenhouse soils (Spain)

2011

Abstract This study determines extractable levels of Cd, Cu, Pb, Zn, Ni and Co in western Almeria (Spain) greenhouse surface soil horizons using EDTA solution, which is identified as the fraction available for organisms and plants. It also establishes background levels, geochemical baseline concentration and reference values (RV), and investigates the possible relationships between soil properties and elemental concentrations. The results show that the soil concentration of these extractable heavy metals was high as those reported by other authors for Spanish agricultural soils. The available RV concentrations obtained (mg kg −1 ) were: Cd 0.17, Cu 1.6, Pb 13.8, Zn 5.0 Ni 1.7 and Co 2.9. Us…