Search results for "Valency"
showing 10 items of 70 documents
Biowaiver Monographs for Immediate-Release Solid Oral Dosage Forms: Enalapril
2018
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence testing for the marketing authorization of immediate-release, solid oral dosage forms containing enalapril maleate are reviewed. Enalapril, a prodrug, is hydrolyzed by carboxylesterases to the active angiotensin-converting enzyme inhibitor enalaprilat. Enalapril as the maleate salt is shown to be highly soluble, but only 60%-70% of an orally administered dose of enalapril is absorbed from the gastrointestinal tract into the enterocytes. Consequently, enalapril maleate is a Biopharmaceutics Classification System class III substance. Because in situ conversion of the maleate salt to the sodium salt is sometim…
The effect duration of candesartan cilexetil once daily, in comparison with enalapril once daily, in patients with mild to moderate hypertension.
2001
To determine the antihypertensive efficacy, effect duration and safety of the angiotensin II type 1 receptor blocker candesartan cilexetil and the angiotensin converting enzyme inhibitor enalapril once daily in patients with mild to moderate hypertension.A multicenter, randomised, double-blind parallel group study was performed in Finland, France, the Netherlands, Spain and Sweden. Three-hundred-and-ninety-five men and women in the age range 20-80 years with primary hypertension were randomised to an 8-week double-blind treatment period with either candesartan cilexetil 8-16 mg or enalapril 10-20 mg once daily, with forced dose titration after 4 weeks. Non-invasive ambulatory blood pressure…
Magnetic transitions in double perovskiteSr2FeRe1−xSbxO6(0⩽x⩽0.9)
2006
The double perovskites ${\mathrm{Sr}}_{2}\mathrm{Fe}M{\mathrm{O}}_{6}$ $(M=\mathrm{Re},\mathrm{Mo})$ belong to the important class of half-metallic magnetic materials. In this study we explore the effect of replacing the electronic $5d$ buffer element Re with variable valency by the main group element Sb with fixed valency. X-ray diffraction reveals ${\mathrm{Sr}}_{2}{\mathrm{FeRe}}_{1\ensuremath{-}x}{\mathrm{Sb}}_{x}{\mathrm{O}}_{6}$ $(0lxl0.9)$ to crystallize without antisite disorder in the tetragonally distorted perovskite structure (space group $I4∕mmm$). The ferrimagnetic behavior of the parent compound ${\mathrm{Sr}}_{2}{\mathrm{FeReO}}_{6}$ changes to antiferromagnetic upon Sb subst…
Verwey-type transition in EuNiP
2006
High temperature 151Eu Mossbauer measurements provide proof for inhomogeneous mixed-valent behaviour in EuNiP. We observed that EuNiP undergoes a Verwey-type charge delocalisation transition when heated above 470 K prior to the structural γ-β phase transition at T ≈ 510 K. This finding confirms the results of photoemission spectroscopy in the isostructural compound EuPdP and of TB-LMTO-ASA band structure calculations. We discuss the role of a van Hove singularity associated with a high density of 4f states close to the Fermi energy in inhomogeneous mixed europium valency, and the microscopic mechanism of γ-β phase transition in compounds analogous to EuNiP.
Autobiographical texts written by learners of Catalan as an Additional Language: From formative needs to reflection in the teaching of narrative genr…
2022
In this article we analyse autobiographical narrative texts written by university students studying Catalan as an Additional Language at a CEFR (2020) B1 level. The goal is to analyse the formative needs related to the writing of this genre in order to foster metadiscursive reflection in the classroom that will allow students to improve their written output. To this end, we analyzed a corpus of 39 autobiographies at both the macrotextual level (i.e., rhetorical moves) and the microtextual level (i.e., deictic elements which channel the narrative’s organization). Our results show that the problems that these texts present for students are related to awareness of the elements that define the …
Biowaiver Monographs for Immediate-Release Solid Oral Dosage Forms: Folic Acid.
2018
This work presents a review of literature and experimental data relevant to the possibility of waiving pharmacokinetic bioequivalence studies in human volunteers for approval of immediate-release solid oral pharmaceutical forms containing folic acid as the single active pharmaceutical ingredient. For dosage forms containing 5 mg folic acid, the highest dose strength on the World Health Organization Essential Medicines List, the dose/solubility ratio calculated from solubility studies was higher than 250 mL, corresponding to a classification as "not highly soluble." Small, physiological doses of folic acid (≤320 μg) seem to be absorbed completely via active transport, but permeability data f…
Influence on the phase transitions of barium titanate of the manganese valency, introduced as a substituant in the titanium site
1991
Abstract A small amount of manganese introduced in BaTiO3 modifies strongly the vibrational and electronic properties of the pure compound. Dielectric response and EPR measurements are reported in order to study the influence of the manganese valency on the ferroelectric-paraelectric phase transition.
Biowaiver Monographs for Immediate Release Solid Oral Dosage Forms: Piroxicam
2014
ABSTRACT Literature and experimental data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing piroxicam in the free acid form are reviewed. Piroxicam solubility and permeability, its therapeutic use and therapeutic index, pharmacokinetic properties, data related to the possibility of excipient interactions and reported BE/bioavailability (BA), and corresponding dissolution data are taken into consideration. The available data suggest that according to the current biopharmaceutics classification system (BCS) and all current guidances, piroxicam would be assigned to BCS Class II. The ex…
Pharmacy and pharmacology of biosimilars
2008
Biosimilar medicines are biological medicinal products that can obtain a marketing authorization in the EU after the original product (biological reference medicine) has run out of patent. As a prerequisite, studies including clinical trials are to be conducted to compare the quality, safety, and efficacy of the biosimilar and reference medicine. Due to the specific characteristics of biopharmaceuticals like complex 3-dimensional (glyco) protein structure, immunogenicity, production in living organisms, which causes heterogeneity, complex manufacturing process and analysis, interchangeability of the biosimilar with its reference drug product is not guaranteed. In addition, INN (internationa…
Biowaiver Monographs for Immediate Release Solid Oral Dosage Forms: Cephalexin Monohydrate.
2019
Literature data and results of experimental studies relevant to the decision to allow waiver of bioequivalence studies in humans for the approval of immediate release solid oral dosage forms containing cephalexin monohydrate are presented. Solubility studies were performed in accordance with the current biowaiver guidelines of the Food and Drug Administration, World Health Organization and European Medicines Agency, taking the degradation at some pH values into consideration. Together with solubility and permeability data for cephalexin monohydrate from the literature, it was demonstrated to be a Biopharmaceutics Classification System Class 1 drug. The pharmacokinetic behavior, results of b…