Search results for "indicator"
showing 10 items of 997 documents
Keyhole limpet hemocyanin (KLH), I: Reassociation from Immucothel® followed by separation of KLH1 and KLH2
1997
Abstract Studies of keyhole limpet hemocyanin (KLH) normally require purification of functional complexes directly from living animals. An alternative procedure is described wherein a commercial preparation of KLH which is fully dissociated into its subunits (Immucothel®, biosyn Arzneimittel GmbH) is reassociated in the presence of a high concentration of calcium and magnesium. The reassociation products, when observed by electron microscopy, consist of didecamers, multidecamers and flexible tubules of varying length. The two forms of KLH described previously and designated KLH1 and KLH2, are present in the reassocated mixture as homo-oligomers/polymers and can be separated by selective dis…
The use of direct determination of chromium in human urine by electrothermal atomic absorption spectrometry in diabetic patients.
1991
Statistical characterisation of heavy metal contents inParacentrotus lividusfrom Mediterranean Sea
2014
This work focuses on the estimation of Hg, As, Cr, Ni, Cu, V, Cd and Pb by inductively coupled plasma mass spectrometry in 135 adult specimens of Paracentrotus lividus collected in different coastal areas of Sicily (Gela, Punta Secca, Ragusa (RG), Siracusa, Priolo, Catania, Messina, Milazzo, Brolo and Filicudi), in order to monitor the Mediterranean marine ecosystem by use of sea urchin as bioindicator. Moreover, the paper deals with the statistical classification of the tested samples according to the sampling area based on metal concentrations. The descriptive statistics findings were obtained and, a starting multivariate matrix was built. Data-sets were subjected to Kruskal-Wallis test t…
Determination of chromium in treated crayfish,Procambarus clarkii, by Electrothermal AAS: Study of chromium accumulation in different tissues
1986
In the present study, the authors investigated the accumulation of chromium in muscle, hepatopancreas, antennal glands, and gills of Procambarus clarkii (Girard) from Lake Albufera following Cr(VI)-exposure. Determinations of chromium were made by using Electrothermal Atomic Absorption Spectroscopy and the standard additions method.
Fast enantiomeric separation of uniconazole and diniconazole by electrokinetic chromatography using an anionic cyclodextrin: application to the deter…
2000
The enantiomeric resolution of the fungicides uniconazole and diniconazole was performed using electrokinetic chromatography with cyclodextrins as pseudostationary phase (CD-EKC). A systematic evaluation of several chiral selectors was made. The anionic derivative carboxymethylated-gamma-cyclodextrin (CM-gamma-CD) was found to be the most appropriate for the enantioseparation of fungicides among all cyclodextrins tested. The influence of some experimental conditions such as nature and buffer pH, chiral selector concentration, and temperature on the enantiomeric separation of the compounds studied was also investigated. The use of a 50 mM phosphate buffer (pH 6.5) containing 5 mM CM-gamma-CD…
Comparison of several methods used for the determination of cephalosporins. Analysis of cephalexin in pharmaceutical samples
2002
The precision of UV absorbance of intact and acid degraded cephalosporins, ninhydrin, high performance liquid chromatography and iodometric methods used for analysis of cefoxitin, cefotaxime, cephazolin and cephalexin were compared. To obtain the calibration graphs the analytical signal used were: absorbance, first derivative absorbance, second derivative absorbance and H-point Standard Additions Method by using absorbance values at two selected wavelengths as analytical signal. These methods and calibration graphs were also used for the determination of cephalexin in pharmaceutical samples.
Furosemide assay in pharmaceuticals by Micellar liquid chromatography: study of the stability of the drug.
2000
A simplified high-performance liquid chromatographic procedure is described for the determination of furosemide (4-chloro-N-furfuryl-5-sulphamoylanthranillic acid), which makes use of UV detection, a C18, reversed-phase column, and micellar mobile phases of sodium dodecyl sulphate (SDS) and 1-propanol at pH 3 buffered with phosphate system. The most adequate experimental conditions to handle furosemide solutions in the analytical laboratory are studied. The mixture of furosemide and its degradation products which are formed upon light exposition was resolved with a mobile phase of 0.04 M SDS-2% propanol. Separation of furosemide from its common impurities and the hydrolytic product, 4-chlor…
New data on Calomera panormitana panormitana (Ragusa, 1906) in Sicily (Coleoptera Cicindelidae)
2021
Calomera panormitana panormitana (Ragusa, 1906) (Coleoptera Cicindelidae) is an endemic species of Sicily, of remarkable biogeographic and ecological importance. It belongs to a small group of species of eastern Mediterranean distribution and it is peculiar for living on the low rocky coasts, near the sea. In this paper we provide new and summarized data on the presence of this species in Sicily. We examined its habitat, ecology and phenology in detail, and we provide useful elements for a better protection. In particular, the presence of this species also in some small islands, located at a short distance from the coast, highlights the presence of important refuge areas to be protected and…
Una inaspettata biodiversità valutata con la trappola malaise: il caso dei collemboli di Lampedusa
2013
All‟interno di uno studio sulla biodiversità dell‟entomofauna dell‟Isola di Lampedusa, che verteva principalmente sulla fauna aerea, si sono trovati diversi taxa normalmente appartenenti alla fauna edafica. Infatti per il monitoraggio sono state utilizzate trappole di tipo Malaise internazionalmente impiegate e consigliate nei protocolli per il monitoraggio di popolazioni di insetti volatori. Inaspettatamente, anche se qualche altro caso è citato in letteratura, si sono rinvenuti diversi taxa più tipicamente rappresentativi della fauna del suolo ed in particolare dell‟epifauna quali chilopodi, collemboli, coleotteri carabidi. La nostra attenzione si è focalizzata sui collemboli in quanto so…
Estudio de la relación entre miembros del comité editorial de las revistas científicas de Psicología y su producción según diferentes indicadores bib…
2017
[ES]: El objetivo del presente trabajo es estudiar la relación entre los miembros del comité editorial que publican artículos en revistas de las que forman parte y la propia revista. Los resultados apuntan que los miembros del comité editorial publican sus artículos de forma más rápida frente a los autores que no forman parte del comité, y que no existe colaboración entre los miembros con mayor presencia en diferentes comités, sí habiéndola entre miembros de una misma revista. En 6 de las 10 revistas estudiadas el porcentaje de artículos firmados por algún miembro del comité supera el 25%, y en tres de estas revistas el tiempo de publicación de estos artículos es significativamente inferior…