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排序方式: 共有180条查询结果,搜索用时 250 毫秒
1.
N Lurie J Slater P McGovern J Ekstrum L Quam K Margolis 《Canadian Metallurgical Quarterly》1993,329(7):478-482
BACKGROUND: Emphasis on ensuring women's access to preventive health services has increased over the past decade. Relatively little attention has been paid to whether the sex of the physician affects the rates of cancer screening among women. We examined differences between male and female physicians in the frequency of screening mammograms and Pap smears among women patients enrolled in a large Midwestern health plan. METHODS: We identified claims for mammography and Pap tests submitted by primary care physicians for 97,962 women, 18 to 75 years of age, who were enrolled in the health plan in 1990. The sex of the physician was manually coded, and the physician's age was obtained from the state licensing board. After identifying a principal physician for each woman, we calculated the frequency of mammography and Pap smears for each physician, using the number of women in his or her practice during 1990 as the denominator. Using unconditional logistic regression, we also calculated the odds ratio of having a Pap smear or mammogram for women patients with female physicians as compared with those with male physicians, controlling for the physician's and the patient's age. RESULTS: Crude rates for Pap smears and mammography were higher for the patients of female than male physicians in most age groups of physicians. The largest differences between female and male physicians were in the rates of Pap smears among the youngest physicians. For the subgroup of women enrolled in the health plan for a year who saw only one physician, after adjustment for the patient's age and the physician's age and specialty, the odds ratio for having a Pap smear was 1.99 (95 percent confidence interval, 1.72 to 2.30) for the patients of female physicians as compared with those of male physicians. For women 40 years old and older, the odds ratio for having a mammogram was 1.41 (95 percent confidence interval, 1.22 to 1.63). For both Pap smears and mammography, the differences between female and male physicians in screening rates were much more pronounced in internal medicine and family practice than in obstetrics and gynecology. CONCLUSIONS: Women are more likely to undergo screening with Pap smears and mammograms if they see female rather than male physicians, particularly if the physician is an internist or family practitioner. 相似文献
2.
Margolis Ronald B.; Duckro Paul N.; Merkel William T. 《Canadian Metallurgical Quarterly》1992,23(4):293
Describes a unique multidisciplinary division in which 8 clinical programs are all administered by psychologists working in a university medical center setting. The increasingly complex environment of a university medical center is discussed in terms of academic mission, competitiveness of health care, and professional roles. The development of this division is reviewed in relation to a number of critical issues, such as organizational structure, academic vs clinical demands, business operations, and 1 version of a scientist–practitioner model in practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
The efficacy and cost effectiveness of vaccination against influenza among elderly persons living in the community 总被引:1,自引:0,他引:1
KL Nichol KL Margolis J Wuorenma T Von Sternberg 《Canadian Metallurgical Quarterly》1994,331(12):778-784
BACKGROUND: Despite recommendations for annual vaccination against influenza, more than half of elderly Americans do not receive this vaccine. In a serial cohort study, we assessed the efficacy and cost effectiveness of influenza vaccine administered to older persons living in the community. METHODS: Using administrative data bases, we studied men and women over 64 years of age who were enrolled in a large health maintenance organization in the Minneapolis-St. Paul area. We examined the rate of vaccination and the occurrence of influenza and its complications in each of three seasons: 1990-1991, 1991-1992, and 1992-1993. Outcomes were adjusted for age, sex, diagnoses indicating a high risk, use of medications, and previous use of health care services. RESULTS: Each cohort included more than 25,000 persons 65 years of age or older. Immunization rates ranged from 45 percent to 58 percent. Although the vaccine recipients had more coexisting illnesses at base line than those who did not receive the vaccine, during each influenza season vaccination was associated with a reduction in the rate of hospitalization for pneumonia and influenza (by 48 to 57 percent, P < or = 0.002) and for all acute and chronic respiratory conditions (by 27 to 39 percent, P < or = 0.01). Vaccination was also associated with a 37 percent reduction (P = 0.04) in the rate of hospitalization for congestive heart failure during the 1991-1992 season, when influenza A was epidemic. The costs of hospitalization for all types of illness studied were lower in the vaccinated group during 1991-1992 (range of reduction, 47 to 66 percent; P < 0.005) and for acute and chronic respiratory conditions and congestive heart failure in 1990-1991 (reductions of 37 percent and 43 percent, respectively; P < or = 0.05). Direct savings per year averaged $117 per person vaccinated (range, $21 to $235), with cumulative savings of nearly $5 million. Vaccination was also associated with reductions of 39 to 54 percent in mortality from all causes during the three influenza seasons (P < 0.001). CONCLUSIONS: For elderly citizens living in the community, vaccination against influenza is associated with reductions in the rate of hospitalization and in deaths from influenza and its complications, as compared with the rates in unvaccinated elderly persons, and vaccination produces direct dollar savings. 相似文献
4.
Many school systems, in both the developed and developing world, are implementing educational technology to assist in student learning. However, there is no clear consensus on how to evaluate these new technologies. This paper proposes a comprehensive methodology for estimating the value of a new educational technology in three steps: benefit analysis, through the administration of a well-designed experiment; cost analysis, which incorporates costs to weigh against the benefits; and feasibility analysis, which introduces real-world concerns that may affect the ability to actually implement the technology. To illustrate the methodology, a case study from Chile is used where portable educational video games were introduced into first and second grade classrooms with the aim of improving learning in mathematics and language. This paper demonstrates the importance of all three steps in the evaluation process and provides a framework for future analyses. 相似文献
5.
KL Margolis N Lurie PG McGovern M Tyrrell JS Slater 《Canadian Metallurgical Quarterly》1998,13(8):515-521
Active cytomegalovirus (CMV) retinitis in patients with acquired immunodeficiency syndrome (AIDS) was treated with an intraocular sustained-release ganciclovir implant. A total number of 19 implants were performed in 15 eyes of 9 AIDS patients. The intraocular sustained-release ganciclovir was effective in preventing reactivation of CMV retinitis in 15 of the 19 implants, ineffective in 3, and undetermined in 1. All ineffective cases had been resistant to ganciclovir therapy before the implants. Vision after the therapy was maintained at better than 0.5 except for one eye. There were no serious ocular complications caused by the therapy. Among 5 patients with unilateral CMV retinitis, 2 unaffected eyes developed CMV retinitis during this therapy. In addition, another patient developed presumed CMV infection in other systemic organs. Based on these data, the intraocular sustained-release ganciclovir implant was considered to be useful for the treatment of CMV retinitis in AIDS. 相似文献
6.
Jonathan Boudreau Ross F. Nelson Hank A. Margolis André Beaudoin Luc Guindon Daniel S. Kimes 《Remote sensing of environment》2008,112(10):3876-3890
Aboveground dry biomass was estimated for the 1.3 M km2 forested area south of the treeline in the eastern Canadian province of Québec by combining data from an airborne and spaceborne LiDAR, a Landsat ETM+ land cover map, a Shuttle Radar Topographic Mission (SRTM) digital elevation model, ground inventory plots, and vegetation zone maps. Plot-level biomass was calculated using allometric relationships between tree attributes and biomass. A small footprint portable laser profiler then flew over these inventory plots to develop a generic airborne LiDAR-based biomass equation (R2 = 0.65, n = 207). The same airborne LiDAR system flew along four portions of orbits of the ICESat Geoscience Laser Altimeter System (GLAS). A square-root transformed equation was developed to predict airborne profiling LiDAR estimates of aboveground dry biomass from GLAS waveform parameters combined with an SRTM slope index (R2 = 0.59, n = 1325).Using the 104,044 quality-filtered GLAS pulses obtained during autumn 2003 from 97 orbits over the study area, we then predicted aboveground dry biomass for the main vegetation areas of Québec as well as for the entire Province south of the treeline. Including cover type covariances both within and between GLAS orbits increased standard errors of the estimates by two to five times at the vegetation zone level and as much as threefold at the provincial level. Aboveground biomass for the whole study area averaged 39.0 ± 2.2 (standard error) Mg ha? 1 and totalled 4.9 ± 0.3 Pg. Biomass distributions were 12.6% northern hardwoods, 12.6% northern mixedwood, 38.4% commercial boreal, 13% non-commercial boreal, 14.2% taiga, and 9.2% treed tundra. Non-commercial forests represented 36% of the estimated aboveground biomass, thus highlighting the importance of remote northern forests to C sequestration. This study has shown that space-based forest inventories of northern forests could be an efficient way of estimating the amount, distribution, and uncertainty of aboveground biomass and carbon stocks at large spatial scales. 相似文献
7.
8.
Chaoyang Wu Jing M. Chen Ankur R. Desai David Y. Hollinger M. Altaf Arain Hank A. Margolis Christopher M. Gough Ralf M. Staebler 《Remote sensing of environment》2012
Light use efficiency (LUE) is an important variable characterizing plant eco-physiological functions and refers to the efficiency at which absorbed solar radiation is converted into photosynthates. The estimation of LUE at regional to global scales would be a significant advantage for global carbon cycle research. Traditional methods for canopy level LUE determination require meteorological inputs which cannot be easily obtained by remote sensing. Here we propose a new algorithm that incorporates the enhanced vegetation index (EVI) and a modified form of land surface temperature (Tm) for the estimation of monthly forest LUE based on Moderate Resolution Imaging Spectroradiometer (MODIS) imagery. Results demonstrate that a model based on EVI × Tm parameterized from ten forest sites can provide reasonable estimates of monthly LUE for temperate and boreal forest ecosystems in North America with an R2 of 0.51 (p < 0.001) for the overall dataset. The regression coefficients (a, b) of the LUE–EVI × Tm correlation for these ten sites have been found to be closely correlated with the average EVI (EVI_ave, R2 = 0.68, p = 0.003) and the minimum land surface temperature (LST_min, R2 = 0.81, p = 0.009), providing a possible approach for model calibration. The calibrated model shows comparably good estimates of LUE for another ten independent forest ecosystems with an overall root mean square error (RMSE) of 0.055 g C per mol photosynthetically active radiation. These results are especially important for the evergreen species due to their limited variability in canopy greenness. The usefulness of this new LUE algorithm is further validated for the estimation of gross primary production (GPP) at these sites with an RMSE of 37.6 g C m? 2 month? 1 for all observations, which reflects a 28% improvement over the standard MODIS GPP products. These analyses should be helpful in the further development of ecosystem remote sensing methods and improving our understanding of the responses of various ecosystems to climate change. 相似文献
9.
Margolis SA 《Analytical chemistry》1999,71(9):1728-1732
The disparity between the volumetric and coulometric Karl Fischer methods for the measurement of water in hydrocarbons and hydrocarbon mixtures (oils) has been resolved. The amount of water detected by the volumetric method when the titration vessel solution is homogeneous is higher than that measured coulometrically or volumetrically when the titration vessel solution is heterogeneous. Water in oil that is not measured by the coulometric method when the oil is incompletely dissolved has been shown to reside in the oil phase of the heterogeneous (multiphasic) coulometric vessel suspension. Water that is not measured volumetrically under relatively low chloroform concentrations after the point of transition to a heterogeneous titration vessel solution is reached also appears to reside in the nonaqueous phase of the titration vessel solution. It appears that this water is retained in the hydrocarbon phase in a manner such that it is completely inaccessible to the volumetric or coulometric Karl Fischer reagents. 相似文献
10.
Although one in three women in the United States will die of heart disease, traditionally coronary artery disease (CAD) in women has received less recognition as a public health problem than has the disease in men. To assist practicing physicians in recognizing CAD in women, this article reviews sex differences in risk factors and manifestations of CAD as well as strengths and weaknesses of various diagnostic tests in women. 相似文献