Search results for " availability"
showing 10 items of 287 documents
Hepatic extraction of isosorbide dinitrate in cardiac patients
1983
Hepatic extraction of organic nitrates, including that of isosorbide dinitrate (ISDN), has been thought to be nearly complete in man but has never been directly measured. We examined the time course of plasma ISDN and metabolite concentrations in arterial and hepatic venous blood in four cardiac patients receiving an intravenous ISDN infusion. Apparent hepatic extraction of ISDN was high (90%) at the beginning of infusion but fell to about 44% 1 hr after termination of infusion. The decrease in ISDN concentration gradient across the liver correlates with an increase in plasma isosorbide-5-mononitrate concentration, but a cause-and-effect relationship resulting from metabolite inhibition can…
Bioavailability of nevirapine in rats after oral and subcutaneous administration, in vivo absorption from gastrointestinal segments and effect of bil…
2011
Abstract Nevirapine is a non-nucleoside reverse transcriptase inhibitor of human immunodeficiency virus type-1. The usual dosing regimen is 200 mg twice/day. Reducing the dosing frequency would significantly improve treatment adherence and quality of life of patients. To study new forms of administration, it is necessary to do pre-clinical studies and know the absorption characteristics of nevirapine in laboratory animals. However, there are no studies about its bioavailability in rats and hardly any about its pharmacokinetic. The objectives of this study were to describe the pharmacokinetics of nevirapine in rats after intravenous, oral and subcutaneous administration, to assess its absorp…
Ethical consumerism: a view from Finland
2004
Business ethics and corporate social responsibility have gained more attention in recent years. However, the consumers’ perspective on ethics is still a little researched area. This study reports a survey ( n = 713) on the views of Finnish consumers about ethics in trade. Consumers’ willingness to promote business ethics as well as the obstacles to ethical consumption are investigated. The results of the study show that while the majority of the respondents regard business ethics as important, this attitude does not translate into their choice behaviour. Consumers are uncertain about which products and firms follow ethical rules and which do not. The most important obstacles to ethical cons…
Exercise dependence, eating disorder symptoms and biomarkers of Relative Energy Deficiency in Sports (RED-S) among male endurance athletes
2019
ObjectivesTo explore associations betweenexercise dependence, eating disorder (ED) symptoms and biomarkers of Relative Energy Deficiency in Sports (RED-S) among male endurance athletes.MethodsFifty-three healthy well-trained male cyclists, triathletes and long-distance runners recruited from regional competitive sports clubs were included in this cross-sectional study. The protocol comprised the Exercise Dependence Scale (EXDS), the ED Examination Questionnaire (EDE-Q), measurements of body composition, resting metabolic rate, energy intake and expenditure and blood analysis of hormones and glucose.ResultsParticipants with higher EXDS score displayed a more negative energy balance compared …
The carrying capacity for Mediterranean bivalve suspension feeders: evidence from analysis of food availability and hydrodynamics and their integrati…
2004
Abstract In order to assess the carrying capacity of two Mediterranean areas, the Incze et al. model and its modification were applied. Our measures were carried out in the Gulf of Gaeta (Central MED), where mussels ( Mytilus galloprovincialis ) are intensively cultivated (production of approximately 200 t per year) and the Gulf of Castellammare (Southern MED), where bivalve culture is not widely practised. Velocities of water current and in field filtration rates were measured in each area. Total suspended matter (TSM), suspended chlorophyll-a (CHLa), lipid, protein and carbohydrate concentrations in the particulate were measured seasonally and used as tools to evaluate the trophic status …
Hydrodynamic effects on the origin and quality of organic matter for bivalves: an integrated isotopic, biochemical and transplant study
2006
Different hydrodynamic conditions can affect both the origin and the quality of organic matter available to bivalve molluscs. I chose 2 environments with very different hydrodynamics (a Mediterranean lagoon open to flow and a closed pond), but similar with regard to temperature, salinity, depth, wind exposure and algae coverage, to investigate this. The lagoon was characterised by active flow and bivalve molluscs, whereas the pond was closed off from the lagoon’s main flow but characterised by mussel beds of the highest density ever observed in the western Mediterranean. Biochemical features, 13C and 15N contents of particulate and sedimentary organic matter, and isotopic signatures of domi…
Role of membrane dynamics processes and exogenous molecules in cellular resveratrol uptake: consequences in bioavailability and activities.
2011
In the fields of nutrition prevention and therapy treatment, numerous studies have reported interesting properties of trans-resveratrol (RSV), a natural polyphenol against pathologies such as vascular diseases, cancers, viral infections and neurodegenerative processes. These beneficial effects are supported by more studies showing the pleiotropic actions of RSV. Nevertheless, a crucial question concerning these effects is how the polyphenol, when applied to an organism, gains access to its targets. In this review, we focus on the biochemical and biological parameters involved in RSV transport, particularly the role of the phospholipid bilayer in RSV uptake (passive diffusion, carrier-mediat…
Gut and microbial resveratrol metabolite profiling after moderate long-term consumption of red wine versus dealcoholized red wine in humans by an opt…
2012
Resveratrol exerts a variety of biological and pharmacological activities, which are observed despite its extremely low bioavailability and rapid clearance from the circulation due to extensive sulfation and glucuronidation in the intestine and liver. In order to more accurately quantify all known resveratrol metabolites, a sensitive and optimized analytical assay was developed and validated by pure standards. Methodology improvements aimed to the chromatographic detection of disulfates and sulfoglucuronides, improving resolution of sulfates, by using a buffered solution, with recovery values of resveratrol and its metabolites, even of sulfates, of 99%. The adapted methodology was then appl…
Fluconazole concentrations in pulmonary tissue and pericardial fluid
1997
In order to investigate the clinical efficacy of the triazole antifungal agent fluconazole (FCA) in the treatment of pulmonary mycosis, in the present study the concentrations of fluconazole in human pulmonary tissue, pericardial fluid and serum were determined at 1, 2, 12 and 13 h after intravenous administration of fluconazole 200 mg. The mean FCA concentrations in the serum were 4.04 mg/l (1 h), 3.82 mg/l (2 h), 2.35 mg/l (12 h) and 2.13 mg/l (13 h). The respective FCA levels in the pulmonary tissue were 4.64 mg/kg, 4.54 mg/kg; 3.50 mg/kg and 3.40 mg/kg and the concentrations in the pericardial fluid were 3.86 mg/l, 3.57 mg/l, 2.35 mg/l and 2.13 mg/l. The FCA concentrations in the pulmon…
k-out-of-n systems: an exact formula for the stationary availability and multi-objective configuration design based on mathematical programming and T…
2018
[EN] Reliability and availability analyses are recognized as essential for guiding decision makers in the implementation of actions addressed to improve the technical and economical performance of complex systems. For industrial systems with reparable components, the most interesting parameter used to drive maintenance is the stationary availability. In this regard, the present paper proposes an exact formula for computing the system stationary availability of a k-out-of-n system. Such a formula is proved to be in agreement with the fundamental theorem of Markov chains. Then, a multi-objective mathematical model is formulated for choosing the optimal system configuration design. The Pareto …