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51.
P Schuman L Capps G Peng J Vazquez W el-Sadr AI Goldman B Alston CL Besch A Vaughn MA Thompson MN Cobb T Kerkering JD Sobel 《Canadian Metallurgical Quarterly》1997,126(9):689-696
BACKGROUND: Candidiasis is a frequent complication of infection with the human immunodeficiency virus (HIV); however, few data exist about the natural history, prevention, and treatment of mucosal candidiasis in women. OBJECTIVE: To evaluate the safety and effectiveness of weekly fluconazole prophylaxis for mucosal candidiasis in women infected with HIV. DESIGN: Randomized, double-blind, placebo-controlled trial. SETTING: 14 sites participating in the Community Programs for Clinical Research on AIDS (CPCRA). PATIENTS: 323 women with HIV infection and CD4+ cell counts of 300 cells/mm3 or less. INTERVENTION: 200 mg of fluconazole per week or placebo. Open-label fluconazole for candidiasis prophylaxis was permitted after two oropharyngeal or vaginal episodes or one esophageal episode. MEASUREMENTS: Development of mucosal candidiasis, clinical and in vitro resistance of Candida species to fluconazole, survival, and adverse events. RESULTS: After a median follow-up of 29 months, 72 of 162 patients receiving fluconazole and 93 of 161 patients receiving placebo had at least one episode of candidiasis (relative risk [RR], 0.56 [95% Cl, 0.41 to 0.77); P < 0.001). Weekly fluconazole was effective in preventing oropharyngeal candidiasis (RR, 0.50 [Cl, 0.33 to 0.74]; P < 0.001) and vaginal candidiasis (RR, 0.64 [Cl, 0.40 to 1.00]; P = 0.05) but not esophageal candidiasis (RR, 0.91 [Cl, 0.48 to 1.72]; P > 0.2). Relative risks were similar for women who had a history of mucosal candidiasis (RR, 0.5 [Cl, 0.35 to 0.75]) and those who did not (RR, 0.69 [Cl, 0.35 to 1.34]). Absolute risk reduction for patients with a history of infection was 25.6 per 100 person-years, which is more than twice the reduction of 11.2 per 100 person-years seen in patients with no history of infection. This difference reflects the higher risk of patients who previously had an infection. Candida albicans was not usually resistant to fluconazole in vaginal specimens in clinical or in vitro settings; such resistance occurred in less than 5% of patients in each group. CONCLUSIONS: Weekly fluconazole (200 mg) seems to be safe and effective in preventing oropharyngeal and vaginal candidiasis. This regimen has a useful role in the management of HIV-infected women who are at risk for recurrent mucosal candidiasis. 相似文献
52.
It is now widely recognized that sulfur dioxide pollution of the atmosphere can no longer be tolerated. Thus, widespread attention has been given to removing sulfur from the fuels that we now burn. Solution of this problem is quite simple for natural gas; at the opposite extreme, for the case of coal, the problem has not yet been solved. This review describes efforts to desulfurize petroleum products, efforts which have been successful to a large extent but which have not achieved the degree of success ultimately required by society. As will be seen, such success presents a catalysis problem which is by no means simple and on which only evolutionary developments have been made to date. Here, then, is an excellent opportunity to exploit years of effort on catalytic theory in a way which will benefit mankind. 相似文献
53.
MR Hee CA Puliafito JS Duker E Reichel JG Coker JR Wilkins JS Schuman EA Swanson JG Fujimoto 《Canadian Metallurgical Quarterly》1998,105(2):360-370
OBJECTIVE: This study aimed to develop a protocol to screen and monitor patients with diabetic macular thickening using optical coherence tomography (OCT), a technique for high-resolution cross-sectional imaging of the retina. DESIGN: A cross-sectional pilot study was conducted. PARTICIPANTS: A total of 182 eyes of 107 patients with diabetic retinopathy, 55 eyes from 31 patients with diabetes but no ophthalmoscopic evidence of retinopathy, and 73 eyes from 41 healthy volunteers were studied. INTERVENTION: Six optical coherence tomograms were obtained in a radial spoke pattern centered on the fovea. Retinal thickness was computed automatically from each tomogram at a total of 600 locations throughout the macula. Macular thickness was displayed geographically as a false-color topographic map and was reported numerically as averages in each of nine regions. MAIN OUTCOME MEASURES: Correlation of OCT with slit-lamp biomicroscopy, fluorescein angiography, and visual acuity was measured. RESULTS: Optical coherence tomography was able to quantify the development and resolution of both foveal and extrafoveal macular thickening. The mean +/- standard deviation foveal thickness was 174 +/- 18 microns in normal eyes, 179 +/- 17 microns in diabetic eyes without retinopathy, and 256 +/- 114 microns in eyes with nonproliferative diabetic retinopathy. Foveal thickness was highly correlated among left and right eyes of normal eyes (mean +/- standard deviation difference of 6 +/- 9 microns). Foveal thickness measured by OCT correlated with visual acuity (r2 = 0.79). A single diabetic eye with no slit-lamp evidence of retinopathy showed abnormal foveal thickening on OCT. CONCLUSIONS: Optical coherence tomography was a useful technique for quantifying macular thickness in patients with diabetic macular edema. The topographic mapping protocol provided geographic information on macular thickness that was intuitive and objective. 相似文献
54.
J Schuman 《Canadian Metallurgical Quarterly》1998,(92):5-14
This article comments on statistics recently published by ONS relating to infant and childhood mortality in 1996. Several factors--birthweight, mother's age, marital status of parents, father's social class, mother's country of birth, multiple birth status, and sex--are known to be associated with the risk of mortality in infants under one year of age. For the first time, ONS is now able to analyse the deaths of 1 and 2 year-old children according to these same factors. The results indicate that these factors are also associated with mortality rates in these older children. 相似文献
55.
We develop an abstract model for our case-study: software to support a “video rental service.” This illustrates how a visual formalism, constraint diagrams, may be used in order to specify such systems precisely. 相似文献
56.
Venkatagireesh Menta Ramabhadraraju Vuppalapati K Chandrashekhara Thomas Schuman Jilun Sha 《Polymer International》2013,62(10):1465-1476
Vacuum‐assisted resin transfer molding (VARTM) is commonly used for general temperature applications (<150 °C) such as boat hulls and secondary aircraft structures. With growing demands for applications of composites in elevated temperature environments, significant cost savings can be achieved by employing the VARTM process. However, implementation of the VARTM process for fabricating elevated temperature composites presents unique challenges such as high porosity and low fiber volume contents. In the present work, a low cost and reliable VARTM process is developed to manufacture elevated temperature composites for aerospace applications. Modified single vacuum bagging infusion and double vacuum bagging infusion processes were evaluated. Details of the method to obtain high quality composite parts and the challenging issues related to the manufacturing process are presented. Density and fiber volume fraction testing of manufactured panels showed that high quality composite parts with void content less than 1% have been consistently manufactured. A property database of the resin system and the composites was developed. A three‐dimensional mathematical model has also been developed for flow simulation and implemented in the ABAQUS finite element package code to predict the resin flow front during the infusion process and to optimize the flow parameters. The results of the present study indicate that aircraft grade composite parts with high fiber volume fractions can be manufactured using the developed elevated temperature VARTM process. © 2013 Society of Chemical Industry 相似文献
57.
S. Wang C. Schuman L. Bao J.S. Lecomte Y. Zhang J.M. Raulot M.J. Philippe X. Zhao C. Esling 《Acta Materialia》2012,60(9):3912-3919
A new selection criterion to explain the activation of the twinning variant is proposed based on the calculation of the deformation energy to create a primary twin. The calculation takes into account the effect of the grain size using a Hall–Petch-type relation. This criterion allows very good prediction for the variant selection to be obtained. The calculations are compared with the experimental results obtained on T40 deformed by rolling. 相似文献
58.
Circumferential distribution of scattering current and small hole coupling for thin finite cylinders
The scattering current induced on a thin finite conducting cylinder immersed in a"theta" -polarizedE -field is studied. Particular attention is paid to the circumferentially nonuniform mode as theE -field angle of incidence varies. This nonuniformity is shown significant (peak-to-average ratio of 3 dB at cylinder midlength) at certain incidence angles for wavelength long cylinders with diameters as small as0.067lambda . Also investigated is the relationship between scattering current and cavity response patterns for narrow thin-walled cylindrical cavities with small holes through which energy is coupled. It is demonstrated theoretically, with experimental verification, that the circumferential variation of scattering current strongly affects the fields within thin cylindrical cavities having apertures with small circumferential extents. It is noted, however, that for most thin-body radiation and scattering problems (in contrast with aperature coupling) only the uniform current mode is significant. 相似文献
59.
Antonia D. Schuman 《Journal of Systems and Software》1981,2(4):329-336
Under the aegis of the Joint Logistics Commanders, the Computer Software Management Subgroup organized two workshops of combined industry and military personnel to review, revise, and recommend new standards for the acquisition and documentation of embedded computer systems. This paper describes the superset of documents which will be required under the new MIL-STD-SDS. The relationship of each document to the acquisition cycle, particularly the design reviews, and to each other, is emphasized. 相似文献
60.
A method for predicting the field penetrating a circumferential opening in a body of revolution is described here. This method employs the method of moments and an aperture equivalence theorem. The former permits rotationally symmetric cavities with otherwise arbitrary contours. The latter improves the sensitivity of field computation when the aperture height is tiny and/or points deep within the cavity are sought. This method is evaluated with comparison to classical theory and experiment via application to spherical and cylindrical cavities. Results for a missile-like cavity irradiated by an obliquely incident plane wave are given. A computer program and user manual is available. 相似文献