Search results for "Fen"
showing 10 items of 3710 documents
Simultaneous Kinetic Determination of Carbamate Pesticides after Derivatization withp-Aminophenol by Using Partial Least Squares
1996
Abstract A method has been developed for the fast spectrophotometric determination of propoxur, carbaryl, and ethiofencarb in water samples using injection analysis in the stopped-flow mode. The method is based on the reaction between p -aminophenol and the phenolic compounds obtained from the pesticides, after a previous hydrolysis with 0.05 M NaOH at room temperature for 15 min. The partial least-squares treatment of the spectrophotometry kinetic data provides a simultaneous determination of the three carbamate pesticides assayed with a relative accuracy error lower than 5% in complex mixtures also containing formetanate, which is only partially hydrolyzed under the experimental condition…
Toxicity of binary mixtures of Cu, Cr and As to the earthworm Eisenia andrei
2020
AbstractChromated copper arsenate (CCA) mixtures were used in the past for wood preservation, leading to large scale soil contamination. This study aimed at contributing to the risk assessment of CCA-contaminated soils by assessing the toxicity of binary mixtures of copper, chromium and arsenic to the earthworm Eisenia andrei in OECD artificial soil. Mixture effects were related to reference models of Concentration Addition (CA) and Independent Action (IA) using the MIXTOX model, with effects being related to total and available (H2O and 0.01 M CaCl2 extractable) concentrations in the soil. Since only in mixtures with arsenic dose-related mortality occurred (LC50 92.5 mg/kg dry soil), it wa…
The lack of the effect of DA-1 and DA-2 dopamine agonists on the isolated guinea-pig atria.
1987
1 The effects of dopamine and both DA-1 and DA-2 dopamine receptor agonists have been studied on the contractile force of electrically driven guinea-pig left atria and frequency of spontaneously beating right atria. 2 Pretreatment of animals with reserpine caused a parallel rightward shift of the concentration-response curve to dopamine of either preparation. 3 Propranolol, but not domperidone, shifted to the right the dose-response curve for the positive inotropic and chronotropic effects of dopamine. 4 Neither apomorphine, fenoldopam, bromocriptine nor piribedil had effects on the frequency and contractile force of the isolated guinea-pig atria. 5 These results suggest that DA-1 and DA-2 …
La reescritura de la leyenda de Tristán e Iseo en "Cligès"
2011
La obra "Cligès", de Chrétien de Troyes, ha sido tradicionalmente considerada por la crítica como una reescritura moralista de la leyenda de Tristán e Iseo. El nuevo sen aplicado por este poeta francés no solo se aplica en el sentido de una relectura del amor cortés más ortodoxa, sino también en el de un mayor realismo literario, más racional y moderno en términos estilísticos. Amor, pasión y adulterio, bajo la pluma de Chrétien, se convierten en nuevos conceptos aptos para establecer una distancia e incluso una confrontación contra el libertinaje poético de sus coetáneos normandos.
Circostanze del reato e tutela del minore
2020
Tradizionalmente considerate elementi accidentali, o accessori, in grado di incidere sulla sola fase della commisurazione della pena, di recente le circostanze del reato hanno attratto l’attenzione della dottrina, della giurisprudenza e dello stesso legislatore, offrendo nuovi spunti di riflessione. Il presente scritto si sofferma sulle implicazioni che scaturiscono dal frequente ricorso alle circostanze, piuttosto che a figure autonome di reato, soprattutto nel delicato settore della protezione del minorenne. In tale ambito, infatti, le circostanze del reato sono state sottoposte ad un processo di proliferazione che potrebbe apparire apprezzabile, rivelandosi espressione di un diritto pena…
The Interaction of Intravenous and Oral Biliary Contrast Agents with Serum Albumins
1978
The binding of two homologous series of oral and intravenous biliary contrast agents to human and bovine serum albumin was investigated using the gel filtration technique and circular dichroism measurements.
Sensing Chiral Drugs by Using CdSe/ZnS Nanoparticles Capped withN-Acetyl-L-Cysteine Methyl Ester
2013
Chiral quantum dots (QDs), differing in their core or shell size and, consequently, in their optical properties, were synthesized by the treatment of commercially available amine-capped quantum dots with methyl ester N-acetyl-L-cysteine (CysP). Interestingly, their colloidal methanol solutions remain stable for several months. Their NMR and IR spectra were in accordance with CysP binding to the QD surface through two anchoring groups; its thiolate (strongly bound) and the carbonyl group of its ester (weaker bound) group, whereas their circular dichroism (CD) spectra showed a new broad redshifted band, suggesting that the attachment to the QD surface modified the conformational equilibrium t…
A Comprehensive Spectroscopic Analysis of the Ibuprofen Binding with Human Serum Albumin, Part II
2021
Human serum albumin (HSA) is the most abundant human plasma protein. HSA plays a crucial role in many binding endos- and exogenous substances, which affects their pharmacological effect. The innovative aspect of the study is not only the interaction of fatted (HSA) and defatted (dHSA) human serum albumin with ibuprofen (IBU), but the analysis of the influence of temperature on the structural modifications of albumin and the interaction between the drug and proteins from the temperature characteristic of near hypothermia (308 K) to the temperature reflecting inflammation in the body (312 K and 314 K). Ibuprofen is a non-steroidal anti-inflammatory drug. IBU is used to relieve acute pain, inf…
Two Latent and Two Hyperstable Polymeric Forms of Human Neuroserpin
2010
AbstractHuman neuroserpin (hNS) is a serine protease inhibitor that belongs to the serpin superfamily and is expressed in nervous tissues. The serpin fold is generally characterized by a long exposed loop, termed the reactive center loop, that acts as bait for the target protease. Intramolecular insertion of the reactive center loop into the main serpin β-sheet leads to the serpin latent form. As with other known serpins, hNS pathological mutants have been shown to accumulate as polymers composed of quasi-native protein molecules. Although hNS polymerization has been intensely studied, a general agreement about serpin polymer organization is still lacking. Here we report a biophysical chara…
Tetrahydroanthraquinone Derivatives from the Endophytic Fungus Stemphylium globuliferm
2015
Four new tetrahydroanthraquinone derivatives, namely, dihydroaltersolanol B (1), dihydroaltersolanol C (2), and the atropisomers acetylalterporriol D (3) and acetylalterporriol E (4), were obtained from the endophytic fungus Stemphylium globuliferum, which was isolated from Juncus acutus growing in Egypt. The structures of the new compounds were unambiguously elucidated on the basis of one- and two-dimensional NMR spectroscopy, as well as by high-resolution mass spectrometry and electronic circular dichroism (ECD) spectroscopy. In addition, seven known anthraquinone derivatives 5–11 were isolated and identified on the basis of their spectral characteristics and by comparison with literature…