Search results for "urea"
showing 10 items of 888 documents
Differences between cysteine and homocysteine in the induction of deoxyribose degradation and DNA damage.
2001
The effect of two naturally occurring thiols, such as cysteine and homocysteine, has been examined for their ability to induce deoxyribose degradation and DNA damage. Copper(II) ions have been added to incubation mixtures and oxygen consumption measurements have been performed in order to correlate the observed damaging effects with the rate of metal catalyzed thiol oxidation. Ascorbic acid plus copper has been used as a positive control of deoxyribose and DNA oxidation due to reactive oxygen species. Cysteine or homocysteine in the presence of copper ions induce the degradation of deoxyribose and the yield of 8-hydroxy-2'-deoxyguanosine (8-OHdG), although important differences are observed…
Plant progesterone 5β-reductase is not homologous to the animal enzyme. Molecular evolutionary characterization of P5βR from Digitalis purpurea
2007
Plants of the genus Digitalis produce cardiac glycosides, i.e. digoxin, which are widely used for congestive heart failure. Progesterone 5beta-reductase (P5betaR) is a key enzyme in the biosynthesis of these natural products. Here, we have carried out the purification and partial amino acid sequencing of the native P5betaR from foxglove (Digitalis purpurea), and isolated a cDNA encoding this enzyme. Similarly to other steroid 5beta-reductases, the recombinant P5betaR catalyzes the stereospecific reduction of the Delta(4)-double bond of several steroids with a 3-oxo,Delta(4,5) structure. The gene encoding P5betaR is expressed in all plant organs, and maximally transcribed in leaves and matur…
Chromatographic fingerprint, antioxidant activity, and colour characteristic of polish goldenrod (Solidago virgaurea L.) honey and flower
2018
In recent times, the nutraceutical and pharmaceutical interest in honey due to its well-known health properties has increased. Consumers need clear and precise information, so that they can make informed choices about their diet and the foods they buy. Therefore, gas chromatography–mass spectrometry (GC–MS) and high-performance liquid chromatography with a photodiode array detector (HPLC-PAD) was revealed a general characteristic fingerprint of polish monofloral goldenrod honey and flowers. In addition, high-performance thin-layer chromatography (HPTLC) has proven to be a useful tool for determining similarity patterns of common bands among honey from the same floral source and thus can be …
Apdrošināšanas sistēmas integrācija ar Azerbaidžānas obligātās apdrošināšanas biroju
2018
“Apdrošināšanas sistēmas integrācija ar Azerbaidžānas obligātās apdrošināšanas biroju” ir integrācija starp Azerbaidžānas apdrošinātāja Xalq polišu pārvaldības sistēmu un Azerbaidžānas obligātās apdrošināšanas biroju (CIB). Integrācijas iemesls - CIB pieņēma lēmumu izveidot jaunu polišu izdošanas sistēmu. Iepriekšējā sistēmā katram apdrošinātājam bija sava polišu pārvaldības sistēma. CIB nodrošināja tīmekļa servisus, kurus izmantojot, apdrošinātājs varēja izdot polises CIB sistēmā. Jaunajā sistēmā apdrošinātāji nevar izdot vai modificēt polises individuālajā sistēmā - visas polises tiek izdotas un modificētas tikai caur CIB sistēmu. Pēc CIB nosacījumiem, visiem apdrošinātājiem savās sistēmā…
Leveraging a Wiki to EnhanceVirtual Collaboration in the Emergency Domain
2008
In a crisis situation, critical success factors include good preparedness, the availability of trustworthy information and reliable people, and the responders' ability to improvise with the available, functioning tools. Wikis can be used as collaborative group support systems to support these activities, especially for communities of practice that must operate as high reliability organizations. The advantages of using a wiki are especially beneficial in volatile environments, such as those in the emergency domain, where critical real-time decision making is required. An international wiki emergenciWiki.org - has been created and is being used by both practitioners and academics. The conclus…
The Evaluation of Public Managers’ Performances in the Light of Italian Public Administration Reform
2011
One of the most important element in the analysis of public administration’s performances is the management. In fact it is the connection point between objectives (fixed at political level) and the system of outputs and outcomes, achieved by public personnel at different levels. This is the main reason why during the last decades, the reform of Italian public administration has concentrated on improving public action performances, by a regulation of public management and the connected introduction of two key words: autonomy and accountability. This means that managers should be endowed of greater autonomy in the execution of their managerial activities and, at the same time, they are fully …
Registered nurses' clinical reasoning in home healthcare clinical practice: A think-aloud study with protocol analysis.
2016
Abstract Background The home healthcare context can be unpredictable and complex, and requires registered nurses with a high level of clinical reasoning skills and professional autonomy. Thus, additional knowledge about registered nurses' clinical reasoning performance during patient home care is required. Objectives The aim of this study is to describe the cognitive processes and thinking strategies used by recently graduated registered nurses while caring for patients in home healthcare clinical practice. Design An exploratory qualitative think-aloud design with protocol analysis was used. Settings Home healthcare visits to patients with stroke, diabetes, and chronic obstructive pulmonary…
Synthesis, properties and crystal structure of bis(metiamide)bis(isothiocyanato)nickel(II)
1991
Abstract The crystal structure of Ni(metiamide)2(NCS)2 was determined by X-ray diffraction methods. Unlike cimetidine, which is a tridentate ligand, metiamide (C9H16N4S2): N-Methyl-N-[2-{(5-methylimidazol-4-yl)methylthio}ethyl]thiourea (which also possesses three potential donor sites) is bidentate, coordinated to the nickel atom through N(imidazole) and S(thioether) atoms. The S(thiourea) atom does not take part in the coordination; instead, the isothiocyanate ion is coordinated through nitrogen to the metal atom. The nickel atom lies on a centre of symmetry in an elongated octahedral environment: the nitrogen atoms occupy equatorial positions (NiN = 2.04 and 2.06 A) and S(thioether) atom…
Addition of thiourea and hydrochloric acid: Accurate nanogram level analysis of mercury in humic-rich natural waters by inductively coupled plasma ma…
2020
Abstract An analytical method was developed for the direct determination of total mercury in natural waters at low ng L−1 level by inductively coupled plasma mass spectrometry (ICP-MS). The presented method overcomes previously observed problems relating to poor spike recoveries by adding 0.12% thiourea in addition to 3% HCl to all samples and standards. The sample preparation is fast and easy to perform by the developed method since it requires only the addition of HCl and thiourea to the water samples. A very low instrument detection limit (0.4 ng L−1) was obtained without time-consuming preconcentration procedures. The accuracy and precision of the developed method were found excellent b…
Advantages of monolithic over particulate columns for multiresidue analysis of organic pollutants by in-tube solid-phase microextraction coupled to c…
2011
Abstract The performance of a monolithic C 18 column (150 mm × 0.2 mm i.d.) for multiresidue organic pollutants analysis by in-tube solid-phase microextraction (IT-SPME)-capillary liquid chromatography has been studied, and the results have been compared with those obtained using a particulate C 18 column (150 mm × 0.5 mm i.d., 5 μm). Chromatographic separation has been carried out under isocratic elution conditions, and for detection and identification of the analytes a UV-diode array detector has been employed. Several compounds of different chemical structure and hydrophobicity have been used as model compounds: simazine, atrazine and terbutylazine (triazines), chlorfenvinphos and chlorp…