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991.
AT Lyos GR Evans D Perez MA Schusterman 《Canadian Metallurgical Quarterly》1999,103(2):442-7; discussion 448-9
Advanced carcinoma of the oral cavity is a devastating disease, with the potential for severe speech and swallowing dysfunction. This is a retrospective review documenting the outcome of 14 patients who underwent resection of at least 75 percent of their tongue with preservation of the larynx and an intact mandible. Reconstruction was accomplished with rectus abdominis free tissue transfer. There were seven male and seven female patients between the ages of 25 and 77 years (mean, 55 years) who underwent total (eight patients) or subtotal (six patients) glossectomy and reconstruction. Decannulation of the tracheostomy tube was performed in 12 patients (86 percent) at an average of 3.5 months postoperatively. One patient required interval laryngectomy for intractable aspiration 1 month postoperatively. Independent evaluation of speech, articulation, and deglutition was performed. Fifty percent of patients achieved oral intake of pureed foods or better. Sixty-four percent had acceptable speech. Reconstruction with rectus abdominis free tissue transfer is a viable method for rehabilitation, improving quality of life after total or subtotal glossectomy with laryngeal preservation. 相似文献
992.
Temporal entity-relationship models-a survey 总被引:1,自引:0,他引:1
The entity-relationship (ER) model, using varying notations and with some semantic variations, is enjoying a remarkable and increasing popularity in both the research community-the computer science curriculum-and in industry. In step with the increasing diffusion of relational platforms, ER modeling is growing in popularity. It has been widely recognized that temporal aspects of database schemas are prevalent and difficult to model using the ER model. As a result, how to enable the ER model to properly capture time-varying information has, for a decade and a half, been an active area in the database research community. This has led to the proposal of close to a dozen temporally enhanced ER models. This paper surveys all temporally enhanced ER models known to the authors. It provides a comprehensive overview of temporal ER modeling and it thus meets a need for consolidating and providing easy access to the research in temporal ER modeling. In the presentation of each model, the paper examines how the time-varying information is captured in the model and presents the new concepts and modeling constructs of the model. A total of 19 different design properties for temporally enhanced ER models are defined, and each model is characterized according to these properties 相似文献
993.
Cross-reactions with Fusobacterium necrophorum were found in a PCR designed for detection of a wide range of mycoplasma species. Twenty-five strains of Fusobacterium were examined; all 14 F. necrophorum strains reacted positively, whereas all 7 Fusobacterium nucleatum strains reacted negatively. Two strains that were not F. necrophorum yielded variable results. 相似文献
994.
995.
M Einicker-Lamas AT Malaquias SL de Castro GA Smith MM Oliveira 《Canadian Metallurgical Quarterly》1999,85(3):232-238
Inositol has been cited as being essential for the growth of micro-organisms and animals. Its action rests mostly in the formation of a set of inositol-containing lipids, including phosphatidylinositol and its phosphorylated derivatives. To evaluate the functional responses coupled to the phosphoinositide metabolism in Trypanosoma cruzi we used myo-inositol and its six fluorinated analogues. Their uptake into epimastigotes was characterised using tritium-labeled myo-inositol and monodeoxyfluoro-myo-inositols. The analogues were tested for their ability to inhibit [3H]-myo-inositol incorporation into phosphoinositides and the proliferation of epimastigotes and amastigotes. The results showed differences between T. cruzi and mammalian systems in the responses to the fluorinated analogues. We found that the 3-, 5- and 6-fluoro analogues did not enter the cells but had an inhibitory effect on the incorporation of the radioactive inositol into lipids and on the amastigotes' and epimastigotes' replication. The most effective inhibitor, 1-D-6-deoxy-6-myo-inositol, had no effect on mammalian cell division. 相似文献
996.
Probabilistic and deterministic estimates of the acute and chronic exposure of the Danish populations to dithiocarbamate residues were performed. The Monte Carlo Risk Assessment programme (MCRA 4.0) was used for the probabilistic risk assessment. Food consumption data were obtained from the nationwide dietary survey conducted in 2000--02. Residue data for 5721 samples from the monitoring programme conducted in the period 1998--2003 were used for dithiocarbamates, which had been determined as carbon disulphide. Contributions from 26 commodities were included in the calculations. Using the probabilistic approach, the daily acute intakes at the 99.9% percentile for adults and children were 11.2 and 28.2 microg kg(-1) body weight day(-1), representing 5.6% and 14.1% of the ARfD for maneb, respectively. When comparing the point estimate approach with the probabilistic approach, the outcome of the point estimate calculations was generally higher or comparable with the outcome of the probabilistic approach at the 99.9 percentile (consumers only). The chronic exposures for adults and children were 0.35 and 0.76 microg kg(-1) body weight day(-1) at the 99.9 percentile, representing 0.7% and 1.5%, respectively, of the acceptable daily intake for mancozeb and maneb at 50 microg kg(-1) body weight. 相似文献
997.
Li J.C. Elliott K.R. Matthews D.S. Hitko D.A. Zehnder D. Royter Y. Patterson P.R. Hussain T. Jensen J.F. 《Solid-State Circuits, IEEE Journal of》2009,44(10):2663-2670
Differential amplifiers incorporating the advantages of both Si and III-V technologies have been fabricated in a wafer scale, heterogeneously integrated, process using both 250 nm InP DHBTs and 130 nm CMOS. These ICs demonstrated gain-bandwidth product of 40-130 GHz and low frequency gain > 45 dB . The use of InP DHBTs supports a > 6.9 V differential output swing and a slew rate > 4 times 104V/mus to be achieved with as low as 40 mW dissipated power. A novel on-chip buffer circuit is used to facilitate the on-wafer characterization of these amplifiers. To the authors' knowledge, this is the first demonstration of a high performance IC building block in a heterogeneously integrated process technology. 相似文献
998.
Power system security assessment using neural networks: featureselection using Fisher discrimination
One of the most important considerations in applying neural networks to power system security assessment is the proper selection of training features. Modern interconnected power systems often consist of thousands of pieces of equipment each of which may have an effect on the security of the system. Neural networks have shown great promise for their ability to quickly and accurately predict the system security when trained with data collected from a small subset of system variables. This paper investigates the use of Fisher's linear discriminant function, coupled with feature selection techniques as a means for selecting neural network training features for power system security assessment. A case study is performed on the IEEE 50-generator system to illustrate the effectiveness of the proposed techniques 相似文献
999.
1000.
Fly ash is commonly used as a substitute for cement within concrete in various applications. Manufacturers of reinforced concrete products commonly limit the quantity of fly ash used to 25% or less by weight. Test cylinders with varying percentages of Class C (25-65%) and Class F (25-75%) fly ash and a water-reducing admixture (WRA) were created under field manufacturing conditions and tested for 7-day compressive strength. Seven-day compressive strength for the concrete/fly ash/WRA was found to be highest when the concrete mix included approximately 35% Class C or 25% Class F fly ash. However, substitution ratios of up to 65% Class C or 40% Class F fly ash for cement met or exceeded American Society for Testing and Materials (ASTM) strength requirements for manufacture of Class I, II and III reinforced concrete pipe (RCP). 相似文献