Search results for "reparation"
showing 10 items of 944 documents
Graphene based metal and metal oxide nanocomposites: synthesis, properties and their applications
2015
Graphene, an atomically thin two-dimensional carbonaceous material, has attracted tremendous attention in the scientific community, due to its exceptional electronic, electrical, and mechanical properties. Indeed, with the recent explosion of methods for a large-scale synthesis of graphene, the number of publications related to graphene and other graphene based materials has increased exponentially. Particularly the development of easy preparation methods for graphene like materials, such as highly reduced graphene oxide (HRG) via reduction of graphite oxide (GO), offers a wide range of possibilities for the preparation of graphene based inorganic nanocomposites by the incorporation of vari…
Preparation of Graphene Nanoribbons (GNRs) as an Electronic Component with the Multi-walled Carbon Nanotubes (MWCNTs)
2015
Abstract Carbon nanotubes (CNTs) have a well-defined nanostructure to exhibit high electrical conductivity and chemical stability, and have been used as an advanced material to make electrodes of super-capacitor. Graphene nanoribbons (GNRs), as manufactured by unzipping the CNTs, have more flexible adjustable electrical properties than CNTs, and are regarded an even more promising material for super-capacitor electrodes. This paper presented a series of attempts to prepare GNRs by chemically treating multi-walled carbon nanotubes (MWCNTs); this is, an Oxidation-Reduction method was tried to make GNRs by unzipping MWCNTs longitudinally. Efforts were made in various trials to find conditions …
Uptake from water, biotransformation, and biliary excretion of pharmaceuticals by rainbow trout.
2011
An urgent need exists to assess the exposure of fish to pharmaceuticals. The aim of the present study was to assess the uptake and metabolism of waterborne pharmaceuticals in rainbow trout (Oncorhynchus mykiss). A further objective was to determine the possibility of monitoring exposure to low levels of pharmaceuticals by bile assays. Rainbow trout were exposed for 10 d under flow-through conditions to mixtures of five pharmaceuticals (diclofenac, naproxen, ibuprofen, bisoprolol, and carbamazepine) at high and low concentrations. The low concentration was used to mimic the conditions prevailing in the vicinity of the discharge points of wastewater treatment plants. The uptake and the biocon…
Influence of sample preparation on analytical results: drug analysis [GC/MS] on hair snippets versus hair powder using various extraction methods
1997
The comparison of aqueous extraction methods and hair extraction by organic solvents performed on hair powder as well as on hair snippets of the same sample revealed different qualities of the procedures. Qualitative and quantitative results by the same derivatization step and GC/MS detection demonstrated, that the risk of missing a drug substance is higher using hair snippets than after drug extraction on pulverised hair. Drug recovery for opiates, cocaine and benzoylecgonine from hair was found to be best in aqueous solvents or in methanol extracts. The results are discussed under the aspects of solid-phase extraction, the hair sample representing an inhomogenous material. The localisatio…
On cosmetically treated hair — aspects and pitfalls of interpretation
1997
Popular hair cosmetic treatments like bleaching or permanent waving were found to affect the stability of incorporated drugs and to cause alterations of the fibers at an ultrastructural level. This may result in a partial or complete loss of drug substances, depending on the particular drug molecule and on its concentration prior to the cosmetic treatment. Moreover, from literature, there is some evidence that drug molecules are not only incorporated into the growing fiber by passive diffusion from blood into the matrix cells and melanocytes, but that the substances enter the hair also via perspiration such as sweat and sebum. Since permed and bleached hair shows an enhanced sorption capaci…
Opioid switching from and to tapentadol extended release in cancer patients: conversion ratio with other opioids
2013
Objectives: The aim of this exploratory study was to assess the conversion ratios between tapentadol and other opioids in patients requiring an opioid switching. Methods: A prospective study was carried out in a convenience sample of consecutive patients admitted to an acute palliative care unit and a home care unit for a period of 1 year. Patients who were switched from/to tapentadol were selected. The initial ratio between tapentadol and other opioids, expressed as oral morphine equivalents was 1:3.3. The subsequent doses were flexible and were changed to fit the patients’ needs. Pain intensity and distress score were recorded until opioid doses were stable. In all, 37 patients were exami…
Stability of opiates in hair fibers after exposure to cosmetic treatment.
1996
Abstract The stability of opiates in clipped natural human hair was investigated. Hair fibers were incubated with defined solutions of morphine, codeine and dihydrocodeine (pH 7.4) until saturated. Original opiate-positive hair samples collected from drug addicts also were examined. Commercially available bleaching as well as perming formulas (Poly Blonde Ultra®, Poly Lock®; Henkel, Dusseldorf, Germany) were applied in vitro to the hair strands of both groups under investigation. After these treatments, the drug concentration had decreased for both bleaching and permanent waving. In the spiked hair, only 2–18% of the starting solution could be found after bleaching. About 20–30% of the drug…
Slow release oral morphine versus methadone for the treatment of opioid use disorder
2019
ObjectiveTo assess the efficacy of slow release oral morphine (SROM) as a treatment for opioid use disorder (OUD).DesignSystematic review and meta-analysis of randomised controlled trials (RCTs).Data sourcesThree electronic databases were searched through 1 May 2018: the Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE. We also searched the following electronic registers for ongoing trials: ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, Current Controlled Trials and the EU Clinical Trials Register.Eligibility criteria for selecting studiesWe included RCTs of all durations, assessing the effect of SROM on measures of treatment retention, heroin use…
Nanoassemblies Based on Supramolecular Complexes of Nonionic Amphiphilic Cyclodextrin and Sorafenib as Effective Weapons to Kill Human HCC Cells
2015
Sorafenib (Sor), an effective chemiotherapeutic drug utilized against hepatocellular carcinoma (HOC), robustly interacts with nonionic amphiphilic cyclodextrin (aCD, SC6OH), forming, in aqueous solution, supramolecular complexes that behave as building blocks of highly water-dispersible colloidal nanoassemblies. SC6OH/Sor complex has been characterized by complementary spectroscopic techniques, such as UV-vis, steady-state fluorescence and anisotropy, resonance light scattering and H-1 NMR. The spectroscopic evidences and experiments carried out in the presence of an adamantane derivative, which competes with drug for CD cavity, agree with the entrapment of Sor in aCD, pointing out the role…
Lipid nanocarriers containing sorafenib inhibit colonies formation in human hepatocarcinoma cells
2015
Here, the potential of two nanostructured lipid carriers (NLC) for controlled release of sorafenib was evaluated. The obtained systems showed characteristics suitable as drug delivery systems for the treatment of hepatocellular carcinoma (HCC) through parenteral administration. The use of a mixture between a solid lipid (tripalmitin) with a liquid lipid (Captex 355 EP/NF or Miglyol 812) to prepare NLC systems could give a higher drug loading capacity and a longer term stability during storage than that obtained by using only solid lipids. The obtained nanoparticles showed a nanometer size and high negative zeta potential values. Scansion electron microscopy (SEM) of the sorafenib loaded NLC…