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31.
KJ Guidera J Hooten W Weatherly M Highhouse A Castellvi JA Ogden L Pugh S Cook 《Canadian Metallurgical Quarterly》1993,18(4):427-431
Fifty-two posterior spinal fusions were performed for pediatric idiopathic, congenital, and neuromuscular scoliotic curves. Cotrel-Dubousset instrumentation was used in all patients. Nine had prior anterior spinal releases and fusions. The patterns were mixed, with a predominance of right thoracic curvatures. The average preoperative curve measured 60.6 degrees, with correction to 29. Seven patients required revision surgery, and 17 wore orthoses after operation. There were 17 complications in this group, including hook pullout, prominent hardware, infection, pseudarthrosis, and two cases of broken Cotrel-Dubousset instrumentation rods. Fatigue failure of this instrumentation, secondary to pseudarthrosis, has not been reported previously, and these two cases are presented in detail. The operative morbidity and difficulty were increased in the larger idiopathic curves and in neuromuscular and congenital scoliosis. Cotrel-Dubousset instrumentation is an overall excellent tool for the multiplanar correction of scoliosis and is amenable to revision surgery. 相似文献
32.
33.
BM King JT Cook KN Rossiter LM Theobold H Sam 《Canadian Metallurgical Quarterly》1996,60(6):1569-1571
Bilateral lesions in the most posterodorsal aspects of the amygdala in female rats resulted in immediate and dramatic weight gains on a standard lab chow diet. The rate of weight gain returned to normal by Day 20, but the difference in body weight between animals with amygdaloid lesions and those with sham lesions was maintained for the duration of the study (60 days). Because rats with posterodorsal amygdaloid lesions have also been found to be hyperinsulinemic, it is hypothesized that the lesions result in a similar, though smaller, version of the syndrome that follows lesions of the ventromedial hypothalamus. 相似文献
34.
B Davies D Clarke S Connaughty K Cook B MacKenzie J McCormick M O'Loane C Stutzer 《Canadian Metallurgical Quarterly》1996,22(6):500-507
Interviews with 25 nurses in this grounded theory study show that when nurses recognized that a child's death was inevitable, they struggled with both grief distress and moral distress. Their distress occurred within the context of the nurse-patient relationship. Nurses employed a range of strategies to manage their distress. Several conditions facilitated or constrained nurses' strategies, and resulted in far-reaching implications both professionally and personally. 相似文献
35.
This paper reports on a preliminary study of parenting quality, parental stress and child behaviour in families with twins conceived by in-vitro fertilization (IVF) in comparison with families with naturally conceived twins. No differences were found between the types of family in parenting quality or child behaviour. However, parents whose children were conceived by IVF reported greater stress associated with parenting than parents with naturally conceived twins. 相似文献
36.
Calculated hardenability for improved consistency of properties in heat treatable engineering steels
W. T. Cook P. F. Morris L Woollard 《Journal of Materials Engineering and Performance》1997,6(4):443-448
Hardenability is one of the most important parameters controlling the heat treated properties of engineering steels. It affects
the consistency of response for microstructure, hardness, strength, toughness, and dimensional change (distortion). This study
illustrates that a major benefit of controlling hardenability is improving the consistency of dimensional distortion resulting
from heat treatment. To facilitate the supply of steels to hardenability limits, especially restricted hardenability, a new
technique was developed for the prediction of Jominy hardenability from chemical composition. The technique, termed the “Database
Method,” uses measured Jominy hardenability and chemical composition data, contained in a database, to calculate the hardenability
for a query composition. Using up to ten known steels, selected from the database with compositions closely matching that
of the query steel, a small adjustment is made to the measured hardenability of each known steel allowing for the small difference
in composition between the query and chosen steel. The final calculated result for the query steel is taken as the average
of the various estimates. The basis of the Database Method is explained, and the advantages are illustrated for selecting
engineering grades. 相似文献
37.
Reflectance data for vitrinite occurring in torbanites indicate that the mean maximum reflectance and the range of reflectance values are significantly lowered by the presence of alginite. This is the probable cause of apparently anomalous rank gradients in some deep oil exploration wells. Intermaceral effects need to be considered in assessing rank or maturity from vitrinite reflectance, and by inference, in most other methods. The interpretation of the cause of the effect is open to further study but the findings are highly significant in relation to coal utilization, oil and gas exploration, and studies of oil shales. 相似文献
38.
Fatty acid and cholesterol synthesis in isolated rat hepatocytes were strongly inhibited by 5-(tetradecyloxy)-2-furoic acid.
With either3H2O or [2-14C]acetate as the labeled precursor, the concentrations of inhibitor causing 50% decrease in fatty acid and cholesterol synthesis
were, respectively, <0.005 mM and 0.020 mM. At 0.1 mM inhibitor, citrate concentration in cells from fed rats was increased
by 75%; lactate and pyruvate concentrations were decreased by 30%; ethanol oxidation was decreased by 20%; with cells from
starved rats, the mitochondrial [NAD+]/[NADH] was decreased. Other parameters were unaffected. Both its potency and its specificity indicate that 5-(tetradecyloxy)-2-furoic
acid will be useful in studies on the regulation of lipid biosynthesis. 相似文献
39.
Maud Cansell Noredine Moussaoui Alain Pierre Petit Alain Denizot Nicole Combe 《European Journal of Lipid Science and Technology》2006,108(6):459-467
Two n‐3 polyunsaturated fatty acid (PUFA)‐rich diets differing in their chemical and physical forms were given to rats during 2 wk. Liposomes [phospholipids (PL) organized in bilayer structures] made from a natural marine lipid extract or a mixture of fats containing fish oil [similar fatty acids esterified in triacylglycerols (TAG)] were used. The influence of n‐3 PUFA dietary sources on plasma parameters, i.e. TAG, cholesterol and PL concentrations, was investigated. A similar hypotriglyceridemic effect of n‐3 PUFA from liposomes or fish oil was observed. In contrast, feeding rats with liposomes led to different PL and cholesterol patterns. In the plasma of rats fed liposomes, total cholesterol amounts were positively correlated with PL levels. Liposome and fish oil feedings caused a marked increase in the amounts of n‐3 PUFA, which occurred mainly at the expense of n‐6 PUFA. However, the enrichment in n‐3 PUFA in the different plasma lipid classes differed substantially when ingested in the form of fish oil or liposomes. These results were interpreted in terms of different lipid bioavailability and metabolic fate during the digestive steps and in the liver, with the dietary source. 相似文献
40.
Magnus Moglia Stephen Cook Ashok K. Sharma Stewart Burn 《Water Resources Management》2011,25(1):217-238
This paper reports on the use of qualitative analysis to inform a risk analysis framework for decentralised water systems. To realise the benefits from these technologies, a methodology is applied to learn from previous difficulties in implementing and managing them. A workshop process was used to capture stories from industry professionals on difficulties they have encountered in planning and implementation. Qualitative analysis of story narratives revealed stages where there was some type of development process failure; as well as failure modes and factors influencing the difficulties encountered. The analysis also generated insights: difficulties in one part of the development process tends to propagate to subsequent stages; system difficulties most often occurred in the policy stage of development due to institutional inertia and lack of adaptive governance; and the best indicator of problems with a decentralised system was complaints of poor water quality. Furthermore, this paper also provides a method to learn from past difficulties by identifying what data needs to be collected in order to populate a risk model which can be used for improving risk assessment of the development process for decentralised systems. This can provide a basis for better decision making, policy and guidelines; an important factor in mainstream acceptance. 相似文献