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排序方式: 共有182条查询结果,搜索用时 15 毫秒
121.
The water utility companies in the UK are regulated by the economic regulator to ensure that they do not abuse their monopoly powers and operate under high efficiency targets to minimise costs to their customers. The requirements for improved environmental performance are set by the Environment Agency and, once agreed, incorporated in a five-year plan. Prior to the Water Framework Directive the companies had little choice but to meet a rigorous programme to achieve higher discharge standards as end-of-pipe solutions. The catchment-based approach of the WFD, coupled with the requirement to achieve 'good status' for receiving waters and the requirement for stakeholder involvement, has introduced much needed flexibility into the process which is expected to lead to better and more cost effective solutions to water quality problems. 相似文献
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Interrupted drop-weight tear tests (DWTT) of typical low-strength and high-strength pipe steels were performed at quasi-static
and impact loading rates, to quantitatively characterize crack tunnelling and crack-tip opening angle (CTOA). Crack front
tunnelling was observed in all interrupted DWTT specimens, but the extent of tunnelling varied with the steel grade and the
loading rate. CTOA values measured optically at the surface were higher than those measured at a cross-section close to mid-thickness.
This is attributed to the effect of crack tunnelling, i.e. the effect of constraint, on CTOA. CTOAs derived from load vs.
load-line displacement, using the simplified single-specimen method, are in good agreement with values measured at the mid-thickness. 相似文献
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LB Cleri MG Kris LB Tyson KM Pisters RA Clark RJ Gralla 《Canadian Metallurgical Quarterly》1995,76(5):774-778
BACKGROUND: Intravenous antiemetic combinations containing a 5-HT3 receptor antagonist (like metoclopramide, ondansetron, or granisetron) with dexamethasone have become the standard therapy for the treatment of acute chemotherapy-induced vomiting. Intravenous antiemetics, however, can be more costly and take more time to prepare and deliver, and therefore are not preferred for home, outpatient, or office use. The objective of this study was to determine the antiemetic activity and safety of the oral combination antiemetic regimen of metoclopramide, dexamethasone, and diphenhydramine in patients with small cell lung cancer receiving standard outpatient chemotherapy programs. METHODS: Fifty-two patients receiving initial cisplatin (60 mg/m2) or cyclophosphamide (600-1500 mg/m2) plus doxorubicin (30-45 mg/m2) received an oral regimen of metoclopramide (3 mg/kg x 2 then 2 mg/kg x 2 or 4 doses), dexamethasone (20 mg) and diphenhydramine (50 mg x 2 or 3 doses) (oral MDD), beginning 30 minutes before chemotherapy. RESULTS: Vomiting was prevented in 15 of 21 (76%) patients (95% confidence interval [CI], 53%-92%) receiving cisplatin and 21 of 31 (71%) individuals (95% CI, 52%-86%) given cyclophosphamide plus doxorubicin. Adverse effects were mild and transient and included sedation, loose stools, akathisia, and hiccoughs. CONCLUSIONS: The oral MDD antiemetic regimen prevented acute emesis in 73% of the patients entered and was well tolerated in this population of patients with small cell lung cancer. 相似文献
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DD Ivy SR Neish OA Knudson MR Nihill MS Schaffer RW Tyson SH Abman EM Shaffer L Valdes-Cruz 《Canadian Metallurgical Quarterly》1998,81(6):740-748
We sought to describe the morphologic characteristics of pulmonary arteries by intravascular ultrasound (IVUS) in children with and without pulmonary hypertension to compare these anatomic findings with those of pulmonary wedge angiography, and to determine the relation between these structural findings and functional reactivity to pulmonary vasodilators. Direct evaluation of pulmonary vascular structure in children with pulmonary hypertension with current imaging techniques has been limited and little is known about the relation between structural and functional characteristics of the pulmonary vasculature. In 23 children undergoing cardiac catheterization (15 with pulmonary hypertension and 8 controls) we performed IVUS and pulmonary wedge angiography of the distal pulmonary arteries in the same lobe. IVUS was performed in 44 pulmonary arteries measuring 2.5 to 5.0 mm internal diameter with a 3.5Fr 30-MHz IVUS catheter. We assessed vasoreactivity to inhaled nitric oxide (NO) and oxygen in 13 of 15 children with pulmonary hypertension. Baseline pulmonary vascular resistance (PVR) was greater in the 15 children with pulmonary hypertension than in the 8 controls (9.5+/-1.9 vs 1.5+/-0.3 U x m2, p <0.05). NO lowered PVR in patients with pulmonary hypertension (p <0.05). IVUS studies in patients with pulmonary hypertension showed a thicker middle layer, wall thickness ratio, and diminished pulsatility than did those in controls (p <0.05). The inner layer was not visualized by IVUS in any control patient, but was seen in 9 of 15 patients with pulmonary hypertension. Pulmonary artery wedge angiography correlated with baseline mean pulmonary artery pressure and PVR as well as with IVUS findings of wall thickness ratio and inner layer thickness. The inner layer was not visualized by IVUS in any patient with grade 1 wedge angiograms or in 86% of patients with grade 2 wedge angiograms. All patients with grade 4 and 80% of patients with grade 3 wedge angiograms had a visible inner layer. Vasoreactivity to NO and oxygen did not correlate with structural assessment of the pulmonary vasculature by IVUS. Structural changes in the pulmonary arteries in children with pulmonary hypertension can be directly visualized by IVUS, but are not predictive of NO-induced pulmonary vasodilation. IVUS examination of pulmonary arteries may complement current techniques utilized in the evaluation of children with pulmonary hypertension. 相似文献
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AA Fanaroff SB Korones LL Wright EC Wright RL Poland CB Bauer JE Tyson JB Philips W Edwards JF Lucey 《Canadian Metallurgical Quarterly》1994,330(16):1107-1113
BACKGROUND: Nosocomial infections are a major cause of morbidity and mortality in premature infants. As a rule, their low serum gamma globulin levels at birth subsequently decline to hypogammaglobulinemic values; hence, prophylactic administration of intravenous immune globulin may reduce the rate of hospital-acquired infections. METHODS: In this prospective, multicenter, two-phase controlled trial, 2416 infants were stratified according to birth weight (501 to 1000 g and 1001 to 1500 g) and randomly assigned to an intravenous immune globulin group (n = 1204) or a control group (n = 1212). Control infants were given placebo infusions during phase 1 of the study (n = 623) but were not given any infusions during phase 2 (n = 589). Infants weighing 501 to 1000 g at birth were given 900 mg of immune globulin per kilogram of body weight, and infants weighing 1001 to 1500 g at birth were given a dose of 700 mg per kilogram. The immune globulin infusions were repeated every 14 days until the infants weighed 1800 g, were transferred to another center, died, or were sent home from the hospital. RESULTS: Nosocomial infections of the blood, meninges, or urinary tract occurred in 439 of the 2416 infants (18.2 percent): 208 (17.3 percent) in the immune globulin group and 231 (19.1 percent) in the control group (relative risk, 0.91; 95 percent confidence interval, 0.77 to 1.08). Septicemia occurred in 15.5 percent of the immune globulin recipients and 17.2 percent of the controls. During phase 1 the rate of nosocomial infections was 13.4 percent in the immune globulin group and 17.8 percent in the control group; the respective rates during phase 2 were 21.0 percent and 20.4 percent. The predominant organisms included gram-positive cocci (53.0 percent), gram-negative bacilli (22.4 percent), and candida species (16.0 percent). Adverse reactions were rarely observed during the infusions. Immune globulin therapy had no effect on respiratory distress syndrome, bronchopulmonary dysplasia, intracranial hemorrhage, the duration of hospitalization, or mortality. The incidence of necrotizing enterocolitis was 12.0 percent in the immune globulin group and 9.5 percent in the control group. CONCLUSIONS: Prophylactic use of intravenous immune globulin failed to reduce the incidence of hospital-acquired infections in very-low-birth-weight infants. 相似文献