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31.
This article is based on 4 years of data for a cohort of Medicaid enrollees in California and Georgia to determine patterns of enrollment and expenditures. The analyses were developed from the statistical system known as Tape-to-Tape, which is based on Medicaid enrollment and claims files from these and other States. The composition of the cohort changed over times as a result of the differential rates of turnover for subgroups of the Medicaid population. Longitudinal expenditure patterns also varied by health service and eligibility group. These Medicaid expenditure patterns differed from those observed previously in Medicare studies, undoubtedly reflecting differences in service coverage under Medicare and Medicaid. 相似文献
32.
Bilateral ovarian fibromas in children 总被引:1,自引:0,他引:1
The case of bilateral ovarian fibromas occurring in an 8-year-old black girl is reported. These lesions occur rarely in premenarchal females and may be a manifestation of Nevoid Basal Cell Syndrome. Calcifications are reported to occur rarely in ovarian fibromas but seem to occur frequently in fibromas in children. Management is guided by the benignity of the lesion and consists of surgical excision of the fibroma. Preservation of normal ovarian tissue is recommended with the acknowledged risk of recurrence of the fibroma. 相似文献
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This evaluation examined the diffusion of an innovation entitled the Coalition Index: A Guide to School Health Education Materials. After distributing the Index to a sample of school district health coordinators (n = 39), interviews were completed with 92% of coordinators about their perceptions of the Index and their concern for organizing health resources within their professional role. A one-year follow-up interview was conducted to determine levels of implementation and diffusion. Coordinators responded favorably to the Index as an innovation. Concern scores were limited to those relating to self-management and task-management. Moreover, concern scores demonstrated significant, positive associations (p less than .01) with current use of the Index, and 49% of coordinators were users of the innovation one year after introduction. Results are discussed as they relate to diffusion of innovation stages. 相似文献
36.
Altered swelling behavior of femoral cartilage following joint immobilization in a canine model. 总被引:3,自引:0,他引:3
Daria A Narmoneva Herman S Cheung Jean Y Wang David S Howell Lori A Setton 《Journal of orthopaedic research》2002,20(1):83-91
Periods of reduced joint loading have been shown to induce changes in the biochemical composition. metabolism and mechanics of articular cartilage. In this study, changes in cartilage swelling behavior were studied following a 4-week period of joint immobilization, using a recently developed osmotic loading technique [J. Biomech, 32 (1999) 401-408]. The magnitude and distribution of swelling strains were measured in cartilage-bone samples equilibrated in physiological and hypotonic saline, relative to a hypertonic reference NaCl solution. Physicochemical parameters (glycosaminoglycan fixed charge density and water volume fraction) were determined in site-matched cartilage samples. The experimental data for swelling strains, fixed charge density and water volume fraction were used with a triphasic mechano-chemical theory [J. Biomech. Eng. 113 (1991) 245-258] to determine the effect of joint immobilization on the tensile modulus of the cartilage solid matrix. Four weeks of immobilization resulted in a significant increase in the magnitude of swelling-induced strains, and a significant decrease in fixed charge density in cartilage, as compared with the contralateral controls. Joint immobilization also resulted in decreases in values for the modulus of cartilage, as compared with the contralateral controls. Our results suggest that 4 weeks of joint immobilization had a significant effect on cartilage mechanical function that may be linked to collagen changes in the cartilage extracellular matrix. 相似文献
37.
Devices that are pinned to the tibia to tension an anterior cruciate ligament (ACL) graft produce joint reaction loads that in turn can affect the maintenance of graft initial tension after tibial fixation and hence knee anterior-posterior (AP) load-displacement. However, the effect of these devices on AP load-displacement is unknown. Our objectives were to determine whether tensioning by device versus tensioning by hand causes differences in AP load-displacement and intraarticular graft tension for two commonly used tibial fixation devices: a bioresorbable interference screw and a WasherLoc. AP load-displacement and intraarticular graft tension were measured in 20 cadaveric knees using a custom arthrometer. An initial tension of 110 N was applied to a double-looped tendon graft with the knee at extension using a tensioning device pinned to the tibia and a simulated method of tensioning by hand. After inserting the tibial fixation device, the 134 N anterior limit (i.e., anterior position of the tibia with respect to the femur with a 134 N anterior force applied to the tibia) and 0 N posterior limit (i.e., AP position of the tibia relative to the femur with a 0 N force applied to the tibia) were measured with the knee in 25 degrees flexion. Intraarticular graft tension was measured at extension. These limits and intraarticular graft tension were also measured after cyclically loading the knee 300 times. Compared to a simulated method of tensioning by hand, tensioning with a device pinned to the tibia did not decrease the 134 N anterior limit and did not cause posterior tibial translation. However, intraarticular graft tension was maintained better with a tensioning device pinned to the tibia for the Washerloc, but not the interference screw. For two commonly used tibial fixation devices, a tensioning device pinned to the tibia does not improve AP load-displacement at 25 degrees flexion over tensioning by hand when the graft is tensioned at full extension, but does improve the maintenance of intraarticular graft tension for the Washerloc. 相似文献
38.
R D Clifford M Radford J B Howell S T Holgate 《Archives of disease in childhood》1989,64(8):1126-1132
A sample of 397 from 2503 children aged 7 and 11 years, who took part in an earlier questionnaire study of respiratory symptoms in Southampton, was chosen for methacholine bronchial provocation and allergen skin testing. Results were obtained from 330 (84%). A good level of repeatability was achieved for bronchial provocation testing giving a 95% confidence interval equivalent to 1.74 doubling concentrations. The main problem encountered with methacholine was its bitter taste in high concentrations. The proportion of children, in whom the dose of methacholine which produced a fall of 20% in the forced expiratory volume in one second (PD20 methacholine) was less than or equal to 6.4 mumol, fell from 29.1% at 7 years to 16.5% at 11 years. The prevalence of atopy increased from 26% at 7 years to 31.6% at 11 years. A highly significant association was found between bronchial responsiveness to methacholine and atopy, which was independent of symptoms or age group. 相似文献
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40.
The limited amount of evidence available from mortality statistics, mental hospital in-patient admission rates and community surveys appears to indicate that people of African-Caribbean origin resident in Britain have fewer alcohol-related problems than the white population. However, there are no systematic data on the normal drinking habits of random and representative samples of the black population of Britain, or the true extent of alcohol-related problems in the whole population. A survey of the drinking habits and alcohol-related problems of random samples of 200 black men and 170 white men from the Birmingham and Wolverhampton areas is reported. Black men were much less likely to report regular drinking and to report drinking large amounts of alcohol. They were far less likely to have got drunk in the past year, and scored lower on most items of an Alcohol Problems Scale. Age was the only demographic variable associated with drinking levels in both groups, and the link was more tenuous in the black than the white group. There were no generational differences found. Religious observance and belonging to a Pentecostal Church were found to be major differences between the black and white groups, and strongly associated with moderation in relation to aleohol. 相似文献