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991.
BACKGROUND: Although prophylactic administration of antiemetics reduces the incidence of postoperative nausea, vomiting, or both (PONV), there is little evidence to suggest this improves patient outcomes. The authors hypothesized that early symptomatic treatment of PONV will result in outcomes, including time to discharge, unanticipated admission, patient satisfaction, and time to return to normal daily activities, that are similar to those achieved with routine prophylaxis. METHODS: Men and women (n = 575) scheduled for outpatient surgery during general anesthesia were randomized to receive either 4 mg intravenous ondansetron or placebo before operation and either 1 mg intravenous ondansetron or placebo if postoperative symptomatic treatment of PONV was necessary. Patients were stratified into subgroups by risk factors for PONV. RESULTS: No differences occurred in the time to discharge, rate of unanticipated admission, or time to return to normal activity between the prophylaxis and treatment groups. The reported level of satisfaction with control of PONV was 93% in the treatment arm and 97% in the prophylaxis arm, which fall within the limits defined a priori as clinically equivalent. Female patients with a history of motion sickness or PONV who were undergoing highly emetogenic procedures had a higher reported level of satisfaction with prophylaxis than with treatment (100% vs. 90%, P = 0.043); however, the level of satisfaction with the overall outpatient surgical experience was not different. CONCLUSION: Although PONV is unpleasant, the data indicate little difference in outcomes when routine prophylactic medications are administered versus simply treating PONV should symptoms occur. 相似文献
992.
The class II-associated invariant chain peptide (CLIP) region of invariant chain (Ii) is believed to play a critical role in the assembly and transport of MHC class II alphabetaIi complexes through its interaction with the class II peptide-binding site. The role of the CLIP sequence was investigated by using mutant Ii molecules with altered affinity for the DR1 peptide-binding site. Both high- and low-affinity mutants were observed to efficiently assemble with DR1 and mediate transport to endosomal compartments in COS cell transfectants. Using N- and C-terminal truncations, a region adjacent to CLIP within Ii(103-118) was identified that can complement loss of affinity for the peptide-binding site in mediating efficient assembly of alphabetaIi. A C-terminal fragment completely lacking the CLIP region, Ii(103-216), was observed binding stably to class II molecules in immunoprecipitation studies and experiments with purified proteins. The Ii(103-118) region was required for this binding, which occurs through interactions outside of the alphabeta peptide-binding groove. We conclude that strong interactions involving Ii(103-118) and other regions of Ii cooperate in the assembly of functional alphabetaIi under conditions where CLIP has little or no affinity for the class II peptide-binding site. Our results support the hypothesis that the CLIP sequence has evolved to avoid high-stability interactions with the peptide-binding sites of MHC class II molecules rather than as a promiscuous binder with moderate affinity for all class II molecules. 相似文献
993.
PE León 《Canadian Metallurgical Quarterly》1976,69(2):287-300
4S, 5S, AND 18S + 28S RNA from the newt Taricha granulosa granulosa were iodinated in vitro with carrier-free 125I and hybridized to the denatured chromosomes of Taricha granulosa and Batrachoseps weighti. Iodinated 18S + 28S RNA hybridizes to the telomeric region on the shorter arm of chromosome 2 and close to the centromere on the shorter arm of chromosome 9 from T. granulosa. On this same salamander the label produced by the 5S RNA is located close to or on the centromere of chromosome 7 and the iodinated 4S RNA labels the distal end of the longer arm of chromosome 5. On the chromosomes of B. wrighti, 18S + 28S RNA hybridizes close to the centromeric region on the longer arm of the largest chromosome. Two centromeric sites are hybridized by the iodinated 5S RNA. After hybridization with iodinated 4S RNA, label is found near the end of the shorter arm of chromosome 3. It is concluded that both ribosomal and transfer RNA genes are clustered in the genome of these two salamanders. 相似文献
994.
LaFromboise Teresa; Coleman Hardin L.; Gerton Jennifer 《Canadian Metallurgical Quarterly》1993,114(3):395
A vital step in the development of an equal partnership for minorities in the academic, social, and economic life of the US involves moving away from assumptions of the linear model of cultural acquistion. This article reviews the literature on the psychological impact of being bicultural. Assimilation, acculturation, alternation, multicultural, and fusion models that have been used to describe the psychological processes, social experiences, and individual challenges and obstacles of being bicultural are reviewed and summarized for their contributions and implications for investigations of the psychological impact of biculturalism. Emphasis is given to the alternation model, which posits that an individual is able to gain competence within 2 cultures without losing his or her cultural identity or having to choose one culture over the other. Finally, a hypothetical model outlining the dimensions of bicultural competence is presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Shaoyan Li Willem C Sauer Suxi Huang Robert T Hardin 《Journal of the science of food and agriculture》1998,76(3):347-356
Studies were carried out to determine the effect of soybean trypsin inhibitors (SBTI) on exocrine pancreatic secretions in growing pigs. Six barrows with an average initial body weight (BW) of 27·1±1·4 kg were fitted with permanent pancreatic re-entrant cannulas and fed two diets according to a crossover design. Two maize starch-based diets were formulated to contain 200 g kg−1 crude protein from either Nutrisoy (food grade defatted soy flour) or autoclaved Nutrisoy. The concentrations of SBTI in Nutrisoy and autoclaved Nutrisoy diets were 13·4 and 3·0 g kg−1, respectively. The experiment consisted of two periods of 9 days each. The average BW at the start of the first and second experimental periods was 33·5±2·7 and 37·2±3·7 kg, respectively. The average BW at the conclusion of the experiment was 41·8±3·9 kg. The volume of pancreatic secretion was higher (P<0·01) when the Nutrisoy, as opposed to the autoclaved Nutrisoy diet was fed (3804 vs 2634 ml (24 h)−1). The concen-tration of nitrogen and protein and specific activities (units litre−1) of amylase, chymotrypsin and trypsin were lower (P<0·05) in pancreatic juice of pigs fed the Nutrisoy diet. There were no differences (P>0·05) in the total secretions of nitrogen (g (24 h)−1) and total activities (units (24 h)−1) of amylase, lipase, chymotrypsin and trypsin in pancreatic juice of pigs fed the Nutrisoy and autoclaved Nutrisoy diets. However, the total secretion of protein was slightly higher (25·7 vs 22·8 g (24 h)−1; P<0·05) in pancreatic juice of pigs fed the autoclaved Nutrisoy diet, which corresponded with the increase in the secretion of protein-bound amino acids. There was also an increase in the total secretion of free amino acids in pancreatic juice. These studies show no effect of SBTI on the total enzyme activities in pancreatic juice of growing pigs. © 1998 SCI. 相似文献
996.
997.
T.H. Muster A.E. Hughes T. Harvey S. Hardin D. Lau P.A. White J. Mardel J.M.C. Mol 《Electrochimica acta》2009,54(12):3402-9699
A method is described for the rapid screening of water-soluble corrosion inhibitors, which involves a fixed potential being applied between identical electrodes while immersed in an inhibitor solution. The current flowing between the electrodes is measured and the electrochemical response of the anodic and cathodic reactions, with and without the inhibitor, is then compared. The incorporation of nine pairs of metallic wires (Al, AA2024, AA7075, Fe, mild steel, SS316, Mg, Mg-AZ31 and Zn) into a single assembly enables the effect of inhibitors on different metals to be assessed rapidly. The technique is sensitive to both anodic and cathodic inhibition mechanisms and can provide information on the concentration dependency of inhibitors.This paper provides an electrochemical analysis of the method and demonstrates its application using several soluble chemical species (potassium dichromate, cerium nitrate, sodium vanadate, sodium diphosphate, sodium octanoate) on AA2024-T3 and mild steel at 10−2 and 10−4 M and correlates the results with those obtained by conventional potentiodynamic polarization analysis. The errors in the approach were higher for poor inhibitors, however, efficient corrosion inhibitors have decreased experimental errors, thus, ensuring that promising inhibitor candidates are not overlooked. 相似文献
998.
We examined whether troglitazone and pioglitazone, antidiabetic thiazolidinediones, would directly induce endothelial cell proliferation or influence cytokine-driven proliferation in vitro. Monolayers of Balb/c mouse aortic endothelial cells were treated with troglitazone or pioglitazone in the absence of fetal bovine serum. Endothelial cells also were exposed to varying concentrations of basic fibroblast growth factor (bFGF) or insulin with or without either thiazolidinedione. After 48 h, 3-[4,5-dimethylthiozol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assays were performed to quantitate endothelial cell proliferation by using the various treatment regimens. The data demonstrate that the antidiabetic thiazolidinediones troglitazone and pioglitazone negligibly affect direct endothelial cell proliferation in vitro. Furthermore, troglitazone and pioglitazone significantly inhibit bFGF-induced endothelial cell mitogenesis, whereas only high concentrations of troglitazone affect insulin-mediated proliferation. 相似文献
999.
To determine the depth of pathogen dispersion and the ability of pathogens to survive in enhanced beef products and spent marinade, beef inside skirt steaks and tri-tip roasts were vacuum tumbled with two commercial marinades. The marinades were inoculated with Escherichia coli O157:H7 and Salmonella Typhimurium, resulting in an approximate count of 5.2 log CFU/ml. Both inside skirt steaks and tri-tip roasts were vacuum tumbled for 1 h and sampled immediately after tumbling (day 0), or were vacuum packaged, stored (ca. 4°C), and sampled on days 7 and 14. Samples of the spent marinade were taken after tumbling (day 0) and on days 3 and 7. For both marinades, Salmonella Typhimurium and E. coli O157:H7 were dispersed throughout the inside skirt steaks during vacuum tumbling. Although Salmonella Typhimurium and E. coli O157:H7 for the skirt steaks were still detectable after 14 days of storage, the log values were lower than those on days 0 and 7. For the tri-tip roasts, the pathogen distribution varied, depending on the thickness of the roasts, and pathogens were detectable on days 0, 7, and 14. The spent marinade sampled on days 0, 3, and 7 showed that the pathogens survived at refrigerated temperatures. Because pathogens can transfer to the interior of beef inside skirt steaks and tri-tip roasts when vacuum tumbled with contaminated marinade and survived during refrigerated storage, establishments should consider the potential food safety risks associated with reuse of marinade during the production of vacuum-tumbled beef products. 相似文献
1000.
L. F. BRAMMER BSc MSc DIC A. M. SCHULTE BSCE MSCE PE MASCE MAWWA 《Water and Environment Journal》1993,7(5):471-478
Network analysis has been practised in the water industry for many years, both in the UK and US, especially for capital investment planning and operational strategies. Driven now by the need to improve and maintain customer service levels, the management of water distribution is beginning to rely more on network analysis techniques. The combination of large, detailed models and easy-to-use software is moving network analysis into new areas of benefits in Severn Trent Water using the Stoner workstation service. By providing a simple, geographic interface with the user, the use of network simulation facilities has been increased tenfold in the company. In addition to the hydraulic benefits, Severn Trent Water has followed a lead from the US with water quality modelling, including nitrate blending, source water mixing and chlorine residual analysis. 相似文献