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991.
H Rabb YM O'Meara P Maderna P Coleman HR Brady 《Canadian Metallurgical Quarterly》1997,51(5):1463-1468
Ischemic acute renal failure (ARF) is a common clinical syndrome, associated with high morbidity and mortality, for which there is no specific therapy. Polymorphonuclear neutrophils (PMN) recruited during reperfusion have been implicated as mediators of renal parenchymal injury in ischemic ARF. Leukocyte adhesion molecules appear to facilitate PMN recruitment in this setting. Complementary studies using monoclonal antibodies, antisense oligonucleotides and gene "knock-out" indicate that blockade of CD11/CD18 integrins and intercellular adhesion molecule-1 (ICAM-1) attenuates ARF in some experimental models of renal ischemia. These exciting observations may herald the development of novel anti-adhesion strategies for use in human disease. 相似文献
992.
AP Courcoulas KK Reblock MI Rowe HR Ford 《Canadian Metallurgical Quarterly》1997,32(7):953-6; discussion 956-7
Despite recent advances in the management of high-risk congenital diaphragmatic hernia (CDH), mortality remains high. Deaths occur later because infants with inadequate pulmonary parenchyma are treated aggressively but eventually succumb to respiratory failure. In an attempt to identify absolute predictors of mortality the authors examined retrospectively their experience with CDH to determine if cardiac arrest before repair or initiation of extracorporeal membrane oxygenation (ECMO) invariably increased mortality. The authors reviewed the charts of 119 infants who had high-risk CDH treated between 1981 and 1994. They were divided into two groups: those that suffered cardiopulmonary arrest (CA, n = 21) before CDH repair or ECMO cannulation; and those that did not (NCA, N = 98). The authors compared mortality rate, ventilatory parameters, duration of, and complications on ECMO, as well as length of hospitalization between groups. Twenty-one infants suffered CA before initiation of ECMO support or CDH repair. Three infants (14%) suffered CA before arrival at our institution; seven (33%) after, and 11 (53%) both before and after arrival. There was no difference between the CA and NCA groups in terms of birth weight, gestational age, race and gender mix, or pregnancy and delivery complications. Five-minute Apgar scores were significantly lower in the CA group compared with the NCA group (4.6 v 5.7, P = .04). The CA group also had significantly worse "best postductal" blood gas and ventilatory parameters. There was no significant difference in length of hospitalization, time from admission to ECMO cannulation or CDH repair, or incidence of complications while on ECMO between the two groups. CA cases were more likely to require ECMO support (76% v 48%, P = .02) and to stay on ECMO for a more prolonged period than NCA cases (5.8 v 3.8 days, P = NS). However, there was no significant difference in overall survival between CA and NCA cases (43% v 51%, P = NS). Cardiopulmonary arrest before repair of CDH or ECMO cannulation is not a univariate independent predictor of mortality and therefore should not preclude these high-risk infants from maximum intensive care therapy, including ECMO cannulation. 相似文献
993.
F Gallucci HR Bird C Berardi V Gallai P Pfanner A Weinberg 《Canadian Metallurgical Quarterly》1993,32(5):1051-1058
OBJECTIVE: The objective of this study was to complete a teacher questionnaire on a sample of children (N = 232) in nine fourth grade classes in schools in two regions of central Italy to assess the frequency of occurrence of symptoms of attention-deficit hyperactivity disorder (ADHD) and the rates of probable cases in the sample. METHOD: Each ADHD symptom was rated by the teacher as either absent (0), sometimes present (1) or frequently present (2). RESULTS: Of the children 3.9% had eight or more DSM-III-R Criterion A symptoms of ADHD scored at a "frequent" level (score of 2) and were considered to be "likely cases" of ADHD; an additional 6.9% did not meet this threshold but had a total score of 16 or more on the scale and were considered to be "possible cases." CONCLUSIONS: The findings suggest the need for more systematic epidemiological investigations to evaluate the true prevalence of the syndrome and its risk factors in the Italian population. 相似文献
994.
Elevated plasma testosterone and gonadotropin levels in infertile males with hyperthyroidism 总被引:1,自引:0,他引:1
During the time period, 1 July 1969-30 June 1974, a total of 7056 patients were moved on the C-9A Nightingale on an "urgent" or "priority" basis. In support of the request for urgent airlift, an average of 21 C-9A aircraft were launched monthly. The domestic aeromedical evacuation missions were highly flexible and productive, yet inexpensive when compared with other means of moving patients. A means for determining precedence for the pickup and movement of patients is essential for an aeromedical evacuation system. When the patient is properly evaluated and the urgency for flight movement determined, unnecessary, costly, hazardous, or special flights are avoided. More than 50% of the "urgent" patients airlifted during this 5-year span originated in the central part of the United States. The Northeast and Far West were each responsible for less than 10% of the patients requiring urgent evacuation over the same period. More than 50% of the urgent patients moved were in the categories of newborn complications, burns, and neurological problems. During this period, no patient was moved on an urgent basis for a psychiatric problem--aeromedical evacuation simply becomes a very effective tool in ensuring complete health care for seriously ill patients. 相似文献
995.
Progressive caliceal and ureteral dilatation in postoperative patients is assumed to be secondary to either postoperative distal ureteral stricture or ureteral atony. Any study used to differentiate obstruction from atony must be done with an awareness of the effect of a full bladder on the upper tracts, since it can by itself produce varying degrees of ureteral dilatation. We describe 2 patients who had virtually complete distal ureteral obstruction on anterograde pyelography with a "J" shaped distal ureteral segment. The striking observation was that the deformity and associated distal ureteral obstruction could be made to appear and disappear at will, merely by distending or emptying the bladder. We believe that this is an important factor in the progressive dilatation, as well as in the observed deterioration of renal function, and it is properly regarded as an iatrogenic complication. 相似文献
996.
SA Hundahl HR Menck EG Mansour DP Winchester 《Canadian Metallurgical Quarterly》1997,80(12):2333-2341
BACKGROUND: The National Cancer Data Base (NCDB) represents a national electronic registry system now encompassing almost 60% of incident cancers in the United States. In combination with other programs of the American College of Surgeons Commission on Cancer, the NCDB offers a working example of voluntary, accurate, and cost-effective "outcomes management" on a both a local and a national scale. METHODS: For the accession years 1985-1993, the NCDB has obtained information on demographics, patterns of care, disease stage, treatment, and outcome for a convenience sample of 57,407 gastric carcinoma cases (1.6% of total NCDB cases). In addition to describing trends, this report focuses on 5-year relative survival for a cohort of 1987-1988 cases staged according to the third edition of the American Joint Committee on Cancer's TNM classification, as well as patterns of care for a cohort of 1992-1993 cases. RESULTS: Stage-stratified 5-year relative survival for the 1987-1988 cohort was as follows: IA, 71%; IB, 56%; II, 37%; IIIA, 18%; IIIB, 11%; IV, 5%. Without noteworthy changes in stage distribution, demographics, or other factors, the proportion of patients treated by total gastrectomy is increasing slightly, but proximal gastrectomy for proximal cancers remains surprisingly popular. The proportion of cases receiving postoperative adjuvant treatment has declined slightly. Presumably because of advanced age and/or medical infirmity, a substantial proportion of U.S. patients with disease at every stage receive no treatment for cancer. CONCLUSIONS: This analysis of patterns of care has revealed unexplained variations in treatment and opportunities for improvement. Treatment of the elderly, infirm patient with gastric carcinoma appears problematic. 相似文献
997.
HR Lu P Yang P Remeysen A Saels DZ Dai F De Clerck 《Canadian Metallurgical Quarterly》1999,365(2-3):233-239
We hypothesized that by limiting the Na+ and Ca2+ loading by a blocker/inhibitor of the Na+ channel (lidocaine), Na+ overload (R56865: N-[1-[4-(4-fluorophenoxy)butyl]-4-piperidinyl]-N-methyl-2-benzothiazo lamine), Ca2+ channel (verapamil), Na+ -H+ exchange (ethylisobutyl amiloride) or of Na+ -Ca2+ exchange (No. 7943: 2-[2-[4-(4-nitrobenzyloxy)phenyl]ethyl]isothiourea methanesulfonate), it should be possible to reduce ischemia/reperfusion-induced arrhythmias. To test this hypothesis, we used anaesthetized rats subjected to 5 min of coronary artery occlusion followed by 10 min of reperfusion to study antiarrhythmic effects of above compounds on reperfusion-induced ventricular premature beats, ventricular tachycardia, and reversible and irreversible ventricular fibrillation. Compound or saline was administered as an intravenous bolus injection at 5 min before ischemia. Pretreatment with lidocaine (5 mg/kg), verapamil (0.63 mg/kg), R56865 (0.63 mg/kg) or ethylisobutyl amiloride (1.25 mg/kg) significantly reduced or abolished all types of ventricular arrhythmias. However, pretreatment with verapamil was associated with second or third degree heart block in 3 out of 12 animals. Pretreatment with No. 7943 did not significantly influence the ischemia/reperfusion-induced ventricular arrhythmias. The present results suggest that both intracellular Na+ -and Ca2+ -loading play important roles in reperfusion-induced ventricular arrhythmias and the inhibition of Na+ -Ca2+ exchange to limit Ca2+ loading probably does not play any important role in ischemia/reperfusion-induced arrhythmias in anaesthetized rats. 相似文献
998.
Ali Mohsenatabar Firozjaii Majid Akbari Ghassem Zargar 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2019,41(15):1847-1861
Several factors effect on choosing the best enhanced oil recovery process in a hydrocarbon reservoir. In the present study, effective factors on chemical enhanced oil recovery involved in polymer flooding, surfactant flooding, surfactant–polymer flooding, and alkaline–surfactant–polymer flooding are discussed in numerical simulation. The numbers of the simulation runs are estimated based on the number of factors and their maximum and minimum values using experimental design software. Oil recovery factor from reservoir simulation is considered as comparison factor in all of the run cases. The results from one parameter and two interaction factors during each flooding case were analyzed by Tornado and Parto plot. The oil recovery factor also was estimated using statistical analysis using Minitab. The results show that there is a strong correlation between simulation and statistical analysis. Furthermore, the results show that each selected factor has a different effect on oil recovery in each case of chemical flooding. The case study results on two Iranian oil fields at the end of the present study clarified that results of this study can be useful for selecting the best chemical process for oil reservoir based on reservoir properties. 相似文献
999.
Masoumeh Naderi Morteza Zargar Shoushtari Iraj Kazeminezhad Mehdi Ahmadi Farzaneh Arabpour Roghabadi 《Ceramics International》2018,44(13):15660-15665
In this study, the performance of inverted polymer solar cell was improved using optically and electrically tuned Zn1-xAlxO (x?=?0, 0.005, 0.01 and 0.015) nanorods (AZO) as a high potential electron transporting layer. AZO nanorods with different compositions were synthesized using facile, low temperature, and low cost hydrothermal method that was confirmed by energy dispersive x- ray spectroscopy (EDS) analysis. As revealed, the optical transmittance and optical band gap increased by increasing the Al concentration in AZO nanorods. The fabricated device with ITO/Zn1-xAlxO nanorods / P3HT: PCBM /WO3/Ag structure showed ascending trend for its short-circuit current density (Jsc) by increasing the amount of Al doping. The inverted polymer solar cell with 1% Al doped ZnO nanorods showed a power conversion efficiency of 3.64% that is around 40% higher than that of the device with pure ZnO nanorods (2.58%). The performance enhancement was attributed to the combined effects of the improvement in charge collection and the higher optical transmittance of AZO in the visible range. 相似文献
1000.