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91.
Conlon P.J. Tong Y.P. French P.M.W. Taylor J.R. Shestakov A.V. 《Electronics letters》1994,30(9):709-710
Sub-100 fs pulse generation from a Kerr lens modelocked Cr4+ :YAG laser has been demonstrated for the first time, yielding femtosecond pulses tunable from 1.49 to 1.56 μm with pulses as short as 90 fs obtained at 1.53 μm 相似文献
92.
AIMS: This study was designed to assess the efficacy of low dose methotrexate, 15 mg weekly, as a steroid-sparing agent in asthmatic patients requiring long-term oral prednisone treatment. METHODS: The study was a randomised, double blind, placebo controlled, cross over study of 48 weeks duration. Eleven patients with severe steroid-dependent asthma were included. A successful outcome was defined as a reduction in mean prednisone requirements of 7 mg daily compared to baseline requirements, during active treatment. RESULTS: Two patients were required to be withdrawn owing to methotrexate-related adverse effects. The mean prednisone dose for patients who completed the study was 14.4 mg per day (95% CI; 13.6, 15.1) during active treatment, and 12.9 mg per day (95% CI: 12.2, 13.6) during placebo treatment (NS). Only one patient reduced his individual dose requirements by more than 7 mg per day, whereas in three patients prednisone requirements actually increased during active treatment. There were no significant differences in symptom scores, pulmonary function data, and exacerbations between active and placebo treatments. CONCLUSION: No significant steroid-sparing effect was obtained using low dose methotrexate in this study. This negative outcome may be attributable to the small population of patients studied, low baseline FEV1, and the omission of a steroid minimisation run-in period. Our results highlight the importance of careful patient selection and a painstaking approach in the management of patients with steroid-dependent asthma. 相似文献
93.
94.
A study of eight deaths involving the benzodiazepine flunitrazepam was performed to assess the contribution of this drug to the fatalities. Coronial deaths in Victoria in the 2-year period to mid-1991 were selected in which either flunitrazepam or flunitrazepam and ethanol were the principal toxicological findings. All bodies were subject to a full autopsy by forensic pathologists, and a full toxicological examination. No significant pathology was found at autopsy in any case. Very high concentrations of 7-aminoflunitrazepam, a metabolite of flunitrazepam, were present in all cases. In four cases no other significant drug was detected, whereas in the other four cases there were significant concentrations of ethanol (mean 1.6 g/L). In these two groups of cases the concentrations of 7-aminoflunitrazepam were 0.45 mg/L and 0.16 mg/L, respectively. Only moderate levels of flunitrazepam were detected, suggesting that 7-aminoflunitrazepam is produced postmortem and may be an important marker of flunitrazepam usage. The causes of death in these eight cases were probably either flunitrazepam toxicity or a combination of flunitrazepam and ethanol toxicity. Only one case appeared likely to have been a suicide. Our observations in these cases suggest that flunitrazepam may cause death in the absence of other drugs or significant disease. The presence of ethanol reduces the amount of flunitrazepam needed to cause death. 相似文献
95.
SD Walter SE Birnie LD Marrett SM Taylor D Reynolds J Davies JJ Drake M Hayes 《Canadian Metallurgical Quarterly》1994,84(3):367-376
OBJECTIVES: Our objectives were (1) to describe an analysis of the spatial pattern of cancer incidence in Ontario and (2) to discuss the quality of data in the Ontario Cancer Registry with respect to the accuracy of local cancer rates. METHODS: Cancer incidence rates were calculated for 22 cancer sites in 49 counties of Ontario during 1976 to 1986. Capture-recapture methods were used to estimate completeness of case registration, and completeness of residence information was also assessed. Spatial autocorrelation was used in measuring the geographic pattern of incidence rates. Comparisons were also made between sexes and with earlier data from 1966 to 1975. RESULTS: The quality of the geographic data in the registry appeared good, and corrections for incomplete or inaccurate registration had little impact. About one third of the sex-site combinations showed some evidence of spatial patterning in the cancer rate. Particularly strong regional variation was noted for cancers of the stomach, lung, uterus, and prostate. CONCLUSIONS: The analysis revealed a number of cancers with significant spatial patterning of risk. Further work is needed to relate the cancer data to other information on potential life-style and environmental factors. 相似文献
96.
This paper analyses the HIPERLAN channel access mechanism. Both a purely mathematical and a simulation model are built in order to evaluate the two successive phases of the contention scheme. Several optimisations, based on the choice of parametric values, are proposed, evaluated and compared. 相似文献
97.
结合EPC工程项目管理特点,将质量管理的基本要素充分体现在每一个工作环节,确保工程质量符合规程规范和业主质量目标要求,为机组今后正常稳定运行奠定坚实的基础。 相似文献
98.
99.
Spectrally stable Er-fiber laser for application in phase-sensitive optical time-domain reflectometry 总被引:3,自引:0,他引:3
Kyoo Nam Choi H.F. Taylor 《Photonics Technology Letters, IEEE》2003,15(3):386-388
A high degree of frequency stability in an Er-fiber laser with the Fabry-Perot configuration was achieved using a long (25-km) optical-feedback loop. The frequency-drift rate was determined to be <1 MHz/min by observing temporal fringes in an unbalanced Mach-Zehnder interferometer. Instantaneous linewidth measured with a delayed self-heterodyne interferometer was less than the 3-kHz resolution limit. The laser was utilized in an optical time-domain reflectometry experiment to detect and locate a time-varying phase perturbation applied to an optical fiber. 相似文献
100.