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991.
Choosing the correct equipment for moving and handling patients is essential to prevent injuries among health-care staff and patients' carers. It is vital, however, that a thorough needs and risk assessment is undertaken before equipment is purchased. 相似文献
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Glasses from a complex SiO2-Al2O3-P2O5-CaO-CaF2 glass series, known as 'ionomer glasses' were investigated. For comparison, a sodium-boro-silicate (s-b-s) glass system, which is known to undergo amorphous phase separation was also investigated. Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDX) and BET surface area and pore distribution analysis were the principal analytical techniques used in this study. SEM analysis of the ionomer glass compositions revealed smooth spherical droplets of 2–15 nm while the background morphology appeared rough and speckled. A classic interconnected structure was observed for the s-b-s glass. EDX analysis of the s-b-s glass confirmed that the sodium-borate phase was removed by leaching with 0.3 M HNO3, leaving behind a silica-rich structure. EDX analysis of ionomer glasses leached with 10% NaOH showed that the calcium and phosphate phases were being removed, although not to completion. For the base s-b-s glass a surface area of m 82 g–1 was recorded. However, the base glass after extraction with 0.3 M HNO3 of the sodium borate rich phase gave a BET surface area of 330 m2 g–1 indicating that it had already undergone phase separation on quenching from the melt, giving rise to a fine scale interconnected structure. The leached s-b-s glasses exhibited type 4 adsorption/desorption isotherms characteristic of mesoporous materials. Glasses which had been heat treated at 580°C for 4 h exhibited a surface area of 62 m2 g–1. This indicates that the as-quenched glass is already phase separated and that the phase separated microstructure is coarsening on heat treatment. A surface area of 4 m2 g–1 was measured for the base ionomer glasses. After leaching with 10% NaOH this value rose 10-fold with a maximum surface area of 44.1 m2 g–1 being recorded. The ionomer glasses also exhibited adsorption/desorption isotherms characteristic of mesoporous materials. 相似文献
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P Laidler DA Cowan E Houghton AT Kicman DE Marshall 《Canadian Metallurgical Quarterly》1998,12(14):975-981
Recognition by the legal authorities that growth hormones (GHs) may be abused to improve sporting performance and/or physique has led to the implementation of controls that make it an offence to produce, supply, possess or import and export GHs, with intent to supply, without the authority to do so. A method is described for the discriminatory analysis of human, equine, porcine and bovine GHs for forensic purposes. Peptide-mass mapping by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry following tryptic digestion gave sequence coverages of 97.4%, 93.7%, 94.2% and 90.6% for human, equine, porcine and bovine GHs respectively. The tryptic-mass maps generated were sufficient to discriminate between the four hormones analysed and thus provide unambiguous identification of each individual GH. Identification of the N-terminal peptides of recombinant equine and porcine GHs, which possess additional methionine residues, within the tryptic-mass maps may provide the basis of a test to indicate exogeneous administration rather than endogenous secretion of GH in performance dogs and horses. 相似文献
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WH Cheng YS Ho BA Valentine DA Ross GF Combs XG Lei 《Canadian Metallurgical Quarterly》1998,128(7):1070-1076
A case-control study was conducted between 1992 and 1996 in six Italian areas. It included 537 women with colon cancer, 291 women with rectal cancer and 2081 control women in hospital for acute conditions, unrelated to hormonal or gynaecological diseases. A higher age at menopause was associated with increased colon cancer risk (odds ratio (OR) for > or = 53 years compared with < 50 years = 1.39, 95% confidence interval (CI) 1.04-1.87). Among parous women, a significant trend of decreasing colon cancer risk with increasing number of births was seen for colon (OR for > or = 4 births compared with 1 birth = 0.62, 95% CI 0.42-0.90), but not for rectal cancer. Nulliparous women, however, were at lower risk than women with a single birth, and age at first birth was directly associated with risk. While oral contraceptive use showed no significant influence, ever users of hormone replacement therapy had a reduced risk of rectal cancer (OR = 0.56, 95% CI 0.31-1.01). Thus, the association of colorectal cancer with reproductive and menstrual factors is neither strong nor consistent. 相似文献
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OBJECTIVE: To explore one methodological variation, delay length, that may contribute to contradictory findings in the literature regarding the use of delayed recall in the detection of early-stage dementia of the Alzheimer type. DESIGN: Comparison of participants with dementia and without dementia on a prose recall task at both 10- and 30-minute delay intervals. SETTING: Washington University Alzheimer's Disease Research Center, St Louis, Mo. PARTICIPANTS: Participants with very mild dementia of the Alzheimer type (n = 136) and uncompromised elderly individuals (n = 197). MAIN OUTCOME MEASURES: Results of the Logical Memory subtest from the Wechsler Memory Scale with immediate recall and 10- and 30-minute delayed recall. RESULTS: Participants with dementia recalled significantly less material than elderly controls at both immediate and delayed recall (P < .001). Multiple regression analyses revealed that dementia classification failed to account for additional variance in the 30-minute delayed score beyond that which could be accounted for by the immediate score. A small but significant proportion of variance was accounted for in the 10-minute delayed score beyond that which could be accounted for by the immediate recall score. CONCLUSION: Delayed recall of a prose passage does not appear to enhance the differentiation of very mild dementia of the Alzheimer type from normal aging in a meaningful way, whether the recall delay is 10 or 30 minutes. 相似文献
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