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871.
Paraoesophageal hiatus hernia: an important complication of laparoscopic Nissen fundoplication 总被引:2,自引:0,他引:2
DI Watson GG Jamieson PG Devitt PC Mitchell PA Game 《Canadian Metallurgical Quarterly》1995,82(4):521-523
Postoperative paraoesophageal hiatus hernia occurred in 17 of 253 patients who underwent laparoscopic fundoplication at five different hospitals. Ten patients have undergone subsequent surgical revision, eight by an open technique and two by laparoscopy. This complication may have important implications for the technique of laparoscopic fundoplication, as it is possible that routine posterior repair of the diaphragmatic hiatus may greatly reduce the risk. Early postoperative contrast radiology may also achieve earlier diagnosis, enabling correction to be undertaken by laparoscopy. 相似文献
872.
A haloenol lactone derivative has been synthesized and found to be an isozyme-selective and active site-directed inactivator of glutathione S-transferase (GST). Preincubation of the haloenol lactone (100 microM) with murine Alpha, Mu, or Pi GST isozyme (1.0 microM) at pH 6.5, 37 degrees C resulted in time-dependent loss of enzyme activity with highly selective inhibition of the Pi isozyme (t1/2, approximately 2 min). In a separate experiment, a 10-fold excess of the lactone was incubated with GST-Pi isozyme at 37 degrees C for 3 h, followed by dialysis against Nanopure water. GST activity lost upon incubation with the lactone could not be restored by exhaustive dialysis, and only 8% of enzyme activity for the modified GST remained relative to the control that was treated identically except the lactone was omitted from the incubation. Both control and modified GST were characterized using electrospray ionization mass spectrometry. No native GST (23,478 Da) was observed in the spectrum of modified GST. Instead, protein incubated with the lactone exhibited an increase in molecular mass of 230 Da relative to control GST. The lactone (100 microM) was incubated with GST Pi isozyme (1.0 microM) in the presence of the competitive inhibitor S-hexylglutathione (10 microM), which suppressed time-dependent inhibition of GST by the lactone. The results suggest that this haloenol lactone is an irreversible and active site-directed inhibitor of GST that appears to inhibit the enzyme through two consecutive steps of nucleophilic attack. 相似文献
873.
J Barrette R Bellwied P Braun-Munzinger WE Cleland TM Cormier G David J Dee GE Diebold O Dietzsch JV Germani S Gilbert SV Greene JR Hall TK Hemmick N Herrmann B Hong K Jayananda D Kraus BS Kumar R Lacasse D Lissauer WJ Llope TW Ludlam S McCorkle R Majka SK Mark JT Mitchell M Muthuswamy E O'Brien C Pruneau FS Rotondo J Sandweiss NC daSilva U Sonnadara J Stachel H Takai EM Takagui TG Throwe D Wolfe CL Woody N Xu Y Zhang Z Zhang C Zou 《Canadian Metallurgical Quarterly》1994,50(2):1077-1084
874.
Cyfluthrin (Solfac**) 10 wp, a synthetic pyrethroid was evaluated for its efficacy in malaria control through primary health centre approach, and for its acceptance by the community and effect on human health, and non target organisms, in predominantly tribal areas of Maharashtra and Gujarat from 1988 to 1990. Two dosage schedules; 2 rounds of indoor residual sparying a year, at 25 mg/sq. m2 in Maharashtra, and 3 rounds a year at 15 mg/sq. m2, in Gujarat were followed. There was significant reduction in per man hour densities of An. culicifacies the principal malaria vector, and collaterally of C. quinquefasciatus also. Significant reductions in slide positivity rates and slide falciparum rates were observed in both the areas as compared to the controls. The community acceptance of Cyfluthrin in terms of room coverage was 96% in Gujarat, and 89% in Maharashtra, as against average 68.5% and 55% in case of DDT and Malathion respectively. There were no reported ill-effects on humans or non-target organisms. 相似文献
875.
876.
877.
Few studies have addressed the distinction between concurrent polydrug use (various drugs used on separate occasions) and simultaneous polydrug use (the use of more than 1 drug at the same time). The authors assessed simultaneous polydrug use in a community sample to examine the prevalence of drug combinations, whether simultaneous can be distinguished from concurrent, and the prospective effects of these styles of drug use on subsequent health service utilization, physical symptoms, and psychological distress 4 years later. Marijuana and alcohol were the most common drugs used simultaneously, followed by alcohol and cigarettes. Simultaneous and Concurrent Polydrug Use formed 2 correlated but discriminable constructs. Neither Simultaneous nor Concurrent Polydrug use predicted subsequent Health Service Utilization, Physical Symptoms, or Psychological Distress. Data did reveal unique effects of specific drugs used simultaneously on these outcomes that were larger and more numerous than specific effects of concurrent drug use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
878.
Sixty-six South African Landrace gilts were used in the experiments. At the age of 21 weeks, 47 of the pigs were challenged with halothane exposure. As a result 17 of the pigs died, and were classified stress susceptible (SS), whereas the 30 survivors were classified stress resistant (SR). The other 19 pigs were subjected to treadmill exercise. Four of the exercised pigs died. The pigs that survived the treadmill exercise were later exposed to halothane. The pigs that died as a result of the halothane exposure (n = 5) or the treadmill exercise (n = 4), were classified SS (n = 9) and the survivors as SR (n = 10). A biopsy of the M. semitendinosus was used for measurement of difference in muscle lactate, ATP, glucose 6-phosphate, phosphocreatine, glucose and glycogen concentrations. The results show that in all pigs exercise resulted in the higher stimulation of glycogenolysis than did halothane exposure. However, SS pigs overall showed a greater stimulation of glycogenolysis and glycolysis and general anaerobic metabolism, compared to SR pigs. Under halothane exposure, glycogenolysis and anaerobic metabolism were stimulated in the SS pigs to a much greater extent than in SR pigs, with significant differences between all the muscle metabolites determined. However, treadmill exercise, although sufficient to cause death in some pigs, resulted only in significantly higher lactate and glucose 6-phosphate concentrations. SR pigs exposed to halothane had significantly higher ATP, phosphocreatine and glycogen concentrations, but a lower glucose concentration than exercised SR pigs, indicating less severe stimulation of glycogenolysis by halothane than exercise. No significant differences were found in the determined muscle metabolites in SS pigs exposed to halothane compared to exercised SS pigs. In conclusion, these differences suggest that different mechanisms of stimulation of metabolism on exposure to halothane and exercise may exist, although both types of stress cause stimulation of glycogenolysis. 相似文献
879.
Oxygen transport during oxide growth on (110), (111), and (100) Al crystals at 550°C is investigated by18O/SIMS combined with kinetic measurements and SEM and TEM observations. Starting with an electropolished surface, the experimental evidence suggests oxide growth by oxygen anion transport via local pathways through an outer amorphous Al2O3 layer and oxygen incorporation at the periphery of the underlying laterally growing -Al2O3 islands. The kinetics, island morphology and epitaxy are sensitive to substrate orientation. This oxide growth behavior is compared with oxide formation on a sputter-cleaned and annealed (111) Al surface. 相似文献
880.
Mitchell NB 《Applied ergonomics》1992,23(4):277-280
Subjective data are often the only data available for making decisions and choices in both hardware and software development. These data are therefore both important and valuable. Their importance is such that it is necessary to elicit subjective data from a variety of sources and in a manner that is relatively unbiased. A method which requires participants to compare all criteria and all proposed concepts by pairs provides a non-statistical mechanism for collecting data from a broad base of expertise, for giving appropriate weight to all input, and for reducing personal bias. These characteristics make a comparison of all pairs a useful tool for hardware and software evaluation when decisions and choices must be made. The efficacy of the method was recently demonstrated in the selection of a restraint-attachment device for Space Station Freedom. 相似文献