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David M. Seaman 《Rocks & Minerals》2013,88(5):325-329
Visitors to the November Munich Show will want to allow extra days to see these notable collections in Norway and Denmark. 相似文献
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EK Lang 《Canadian Metallurgical Quarterly》1997,204(3):63A-65A; discussion 66A
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It is pointed out that only the second dielectric wall of an irradiation chamber determines the voltage standing wave ratio within the chamber. Extension of the general method to more complex models is easily accomplished using numerical methods. 相似文献
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The method of determination of the gamma-radiation absorption distribution in microstructures of a biosystem is proposed. The absorption capacity and energy absorption distribution of some biomolecules, mass coefficients and optical density of blood and thyroid gland are calculated. Influence of the pollution of biosystem microstructures (liver, blood, thyroid, gland) by hard elements on the energy absorption distribution is demonstrated. 相似文献
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AL Schwartz PC Van Veldhuisen DE Gaasterland F Ederer EK Sullivan MN Cyrlin 《Canadian Metallurgical Quarterly》1999,127(1):8-19
PURPOSE: To compare the incidence of encapsulated bleb after trabeculectomy in eyes with and without previous argon laser trabeculoplasty and to assess other risk factors for encapsulated bleb development. METHODS: After medical treatment failure, eyes enrolled in the Advanced Glaucoma Intervention Study (AGIS) were randomly assigned to sequences of interventions starting with either argon laser trabeculoplasty or trabeculectomy. In the present study we compared the clinical course for 1 year after trabeculectomy in 119 eyes with failed argon laser trabeculoplasty with that of 379 eyes without previous argon laser trabeculoplasty. Data on bleb encapsulation were collected at the time that the encapsulation was diagnosed, and 3 and 6 months later. RESULTS: Of multiple factors examined in the AGIS data for the risk of developing encapsulated bleb, only male gender and high school graduation without further formal education were statistically significant. Encapsulation occurred in 18.5% of eyes with previous argon laser trabeculoplasty failure and 14.5% of eyes without previous argon laser trabeculoplasty (unadjusted relative risk, 1.27; 95% confidence limits = 0.81, 2.00; P = .23). After adjusting for age, gender, educational achievement, prescribed systemic beta-blockers, diabetes, visual field score, and years since glaucoma diagnosis, this difference remains statistically not significant. Four weeks after trabeculectomy, mean intraocular pressure was 7.5 mm Hg higher in eyes with (22.5 mm Hg) than without (15.0 mm Hg) encapsulated bleb; at 1 year after trabeculectomy and the resumption of medical therapy when needed, this excess was reduced to 1.4 mm Hg. CONCLUSIONS: This study, as did two previous studies, found male gender to be a risk factor for bleb encapsulation. Four studies, including the present study, have reported a higher rate of encapsulation in eyes with previous argon laser trabeculoplasty; in two of the studies, one of which was the present study, the rate was not statistically significantly higher; in the other two studies the rate was significantly higher. The 4-week postoperative mean intraocular pressure was higher in eyes with than without encapsulated bleb; with the resumption of medical treatment the two means converged after 1 year. 相似文献
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