904 resultados para Medical Aspects of Driver Licensing.
Resumo:
This is the last in a series of six papers presenting key findings from a national study that was undertaken to investigate the role and responsibilities of midwives in England and to identify and address continuing educational needs. The background to the study and the titles of other papers in the series have been outlined in the first paper. The first five papers have provided an overview of the main research findings that have been used to determine the continuing educational needs of midwives. This paper provides a more detailed picture of the issues that were identified in relation to educational need, and an overview of the way in which an educational package was developed on the basis of the research findings for use by midwives nationally.
Resumo:
11 Å tobermorite, Ca5Si6O16(OH)2 · 4H2O, is a layer lattice ion exchange mineral whose potential as a carrier for Ag+ and Zn2+ ions in antimicrobial, bioactive formulations has not yet been explored. In view of this, the in vitro bioactivity of Ag+- and Zn2+-exchanged 11 Å tobermorites and their bactericidal action against S. aureus and P.aeruginosa are reported. The in vitro bioactivity of the synthetic unsubstituted tobermorite phase was confirmed by the formation of bone-like hydroxycarbonate apatite (HCA) on its surface within 48 h of contact with simulated body fluid. The substitution of labile Ag+ ions into the tobermorite lattice delayed the onset of HCA-formation to 72 h; whereas, the Zn2+-substituted phase failed to elicit an HCA-layer within 14 days. Both Ag+- and Zn2+-exchanged tobermorite phases were found to exhibit marked antimicrobial action against S. aureus and P.aeruginosa, two common pathogens in biomaterial-centred infections.
Resumo:
In response to a burgeoning interest in the prospective clinical applications of hydraulic calcium (alumino)silicate cements, the in vitro bioactivity and dissolution characteristics of a white Portland cement have been investigated. The formation of an apatite layer within 6 h of contact with simulated body fluid was attributed to the rapid dissolution of calcium hydroxide from the cement matrix and to the abundance of pre-existing Si-OH nucleation sites presented by the calcium silicate hydrate phase. A simple kinetic model has been used to describe the rate of apatite formation and an apparent pseudo-second-order rate constant for the removal of HPO42- ions frorn solultion has been calculated (k(2) = 5.8 x 10(-4) g mg(-1)). Aspects of the chemistry of hydraulic cements are also discussed with respect to their potential use in the remedial treatment of living tissue. (C) 2008 Wiley Periodicals, Inc. J Biomed Mater Res 90A: 166-174, 2009
Resumo:
The uptake of 14C glucose by natural microbial populations has been studied in the Severn Estuary and Bristol Channel, U.K.; the turbidity (suspended solids) in the estuary varied between < 5 mg · 1−1 at the seaward extremity to >800 mg · 1−1 in the estuary proper. The heterotrophic potential, Vm, was found to correlate with turbidity and particulate organic carbon but there was no correlation between microbial biomass, as assessed by plate counts, and turbidity or Vm; measurement of Vm ranged from 0.9 × 10−4 to 288 × 10−4μgC·1−1·h−1 and turnover time from <2 to >100 h. In 17 out of 42 experiments, the uptake of 14C glucose did not conform to Michaelis kinetics and in five of these experiments the data suggested that there may be a threshold of glucose concentration below which there is no uptake.
Resumo:
Marine bivalve molluscs have in recent years attracted considerable attention for a variety of reasons, not least of which is their importance as a source of food for man. Much of this research has concentrated on studies of reproduction; Mytilus viridis (India: Nagabhushanam & Mane, 1975), M. edulis aoteanus and Aulacomya maoriana (New Zealand: Kennedy, 1977);Choromytilus meridionalis and Aulacomya ater (South Africa: Berry, 1978); Mytilus (= Perna) perna (Brazil: Lunetta, 1969); M. edulis planulatus (Australia: Wilson & Hodgkin, 1967); Mytilus californianus and M. edulis (U.S.A.: Hines, 1979); Mytilus galloprovincialis (France: Lubet, 1959) and M. edulis (U.K.: Chipperfield, 1953; Seed, 1975; Bayne et al. 1978). A review of the literature revealed that in the majority of studies cytology was used as a descriptive tool for the ‘staging’ (Chipperfield, 1953; Lubet, 1957; Seed, 1975, 1976) of the developing gametes and certain anomalies were apparent with regard to the nomenclature of the connective tissue matrix of the mantle lobes.
Resumo:
1. Catabolic processes of the phasic and catch parts of the adductor muscle ofPlacopecten magellanicus have been studied in relation to valve snap and valve closure responses. It is concluded that the snap response is powered by both parts of the adductor muscle and the valve closure response is powered exclusively by the catch part. 2. Both parts of the adductor muscle show a high glycolytic potential, reflected by high levels of glycolytic enzymes (Table 1) and high glycogen levels (Table 2). Lactate dehydrogenase could not be detected. In contrast, octopine dehydrogenase shows high activities in both parts of the adductor muscle. It is therefore concluded that a main anaerobic pathway in both tissues is the breakdown of glycogen to octopine. In the catch part, however, a considerable amount of the pyruvate formed from glycogen may also be converted into alanine (see below). The glycolytic flux in the catch part is much higher during the snap response than during valve closure. 3. The absence of phosphoenolpyruvate carboxykinase in the adductor muscle ofP. magellanicus and the observed changes in aspartate, alanine and succinate demonstrate that the energy metabolism in the catch part during valve closure shows great similarities to that which occurs only in the initial stage of anaerobiosis in the catch adductor muscle of the sea musselMytilus edulis L. 4. Arginine kinase activity and arginine phosphate content of the phasic part are much higher than those of the catch part (Tables 1 and 3). This may explain why in the phasic part during the snap response most ATP equivalents are derived from arginine phosphate, and in the catch part during both valve responses most are derived from glycolysis (Table 6). Despite the limited contribution of glycolysis in the phasic part during the snap response, the glycolytic flux increases by a factor of at least 75. 5. Evidence is obtained that octopine is neither transported from one part of the adductor muscle to the other, nor from the adductor muscle to other tissues.
Resumo:
1. Catabolic processes of the phasic and catch parts of the adductor muscle ofPlacopecten magellanicus have been studied in relation to valve snap and valve closure responses. It is concluded that the snap response is powered by both parts of the adductor muscle and the valve closure response is powered exclusively by the catch part. 2. Both parts of the adductor muscle show a high glycolytic potential, reflected by high levels of glycolytic enzymes (Table 1) and high glycogen levels (Table 2). Lactate dehydrogenase could not be detected. In contrast, octopine dehydrogenase shows high activities in both parts of the adductor muscle. It is therefore concluded that a main anaerobic pathway in both tissues is the breakdown of glycogen to octopine. In the catch part, however, a considerable amount of the pyruvate formed from glycogen may also be converted into alanine (see below). The glycolytic flux in the catch part is much higher during the snap response than during valve closure. 3. The absence of phosphoenolpyruvate carboxykinase in the adductor muscle ofP. magellanicus and the observed changes in aspartate, alanine and succinate demonstrate that the energy metabolism in the catch part during valve closure shows great similarities to that which occurs only in the initial stage of anaerobiosis in the catch adductor muscle of the sea musselMytilus edulis L. 4. Arginine kinase activity and arginine phosphate content of the phasic part are much higher than those of the catch part (Tables 1 and 3). This may explain why in the phasic part during the snap response most ATP equivalents are derived from arginine phosphate, and in the catch part during both valve responses most are derived from glycolysis (Table 6). Despite the limited contribution of glycolysis in the phasic part during the snap response, the glycolytic flux increases by a factor of at least 75. 5. Evidence is obtained that octopine is neither transported from one part of the adductor muscle to the other, nor from the adductor muscle to other tissues.