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BackgroundSteep inclination and excessive anteversion angles of acetabular cups could result in adverse edge-loading. This, in turn, increases contact pressure and impingement risk for traditional artificial hip joints. However, the influence of high inclination and anteversion angles on both the kinematics and contact mechanics of dual mobility hip implants has rarely been examined.MethodsThis study focuses on investigating both the kinematics and contact mechanics of a dual mobility hip implant under different inclination and anteversion angles using a dynamic explicit finite element method developed in a previous study.FindingsThe results showed that an inclination angle of both the back shell and liner ranging from 30° to 70° had little influence on the maximum contact pressure and the accumulated sliding distance of inner and outer surfaces of the liner under normal walking gait. The same results were obtained for an anteversion angle of the liner varying between −20° and +20°. However, when the anteversion angle of the liner was beyond this range, the contact between the femoral neck and the inner rim of the liner occurred. Consequently, this caused a relative rotation at the outer articulation.InterpretationsThis suggests that both inclination and modest anteversion angles have little influence on the kinematics and contact mechanics of dual mobility hip implants. However, too excessive anteversion angle could result in a rotation for this kind of hip implant at both articulations. 相似文献
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Juan Manuel Guzmán González 《PM & R》2012,4(10):770-772
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《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(12):3314-3321
Background and aimsHigh sodium intake is associated with a higher risk of a wide range of diseases. We aimed to estimate the pattern and trend of the global disease burden associated with high sodium intake from 1990 to 2019.Methods and resultsWe obtained numbers and rates of death and disability-adjusted life year (DALY) attributable to high sodium intake by sex, socio-demographic index, and country from the Global Burden of Disease Study 2019. We calculated the estimated annual percentage change to evaluate the age-standardized rate (ASR) of the burden attributable to high sodium intake between 1990 and 2019. We further calculated the contribution of population growth, population aging, and age-specific rates of death and DALY to the net change in the total number of deaths and DALYs attributable to high sodium intake. From 1990 to 2019, global age-standardized rates of death and DALY attributable to high sodium intake substantially decreased for both sexes. However, there were significant increases in the total numbers of deaths and DALYs attributable to high sodium intake, which were driven by population growth and population aging. The attribution of population growth and population aging varied widely across countries, with a higher contribution of population growth in most developing countries and a higher contribution of population aging in countries with slow population growth.ConclusionsAlthough the global burden attributable to high sodium intake in terms of age-standardized rate declined from 1990 to 2019, the absolute burden increased significantly, which was driven by population growth and population aging. 相似文献
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《Vaccine》2015,33(16):1941-1947
Nontypeable Haemophilus influenzae (NTHi), a typical mucosal pathogen largely responsible for respiratory infections and pediatric otitis media, has been increasingly recognized as a significant cause of invasive disease, especially in immunocompromised individuals. Lipooligosaccharide (LOS) is a conserved molecule with an important role in H. influenzae virulence and immune evasion, and it may be considered as a vaccine candidate. However, abilities of H. influenzae LOS to induce protective immune response are poorly understood. The goal of this study was to determine whether antibodies against LOS isolated from H. influenzae strains Eagan, Rd and NTHi 375 are present in the sera of normal individuals. Antigen specific IgG and IgM were studied in sera of 71 and 30 healthy adults, respectively. IgG specific for LOS of all three strains was ubiquitously present in our sample population while IgM specific for Eagan, Rd and NTHi 375 LOS compounds was detected in 37%, 63%, and 40% of samples, respectively. All tested serum samples exhibited bactericidal activity against all three H. influenzae strains; the removal of anti-LOS antibodies from the sera resulted in significant increases in bacterial survival of the corresponding strain. NTHi 375 exhibited the highest serum resistance, whereas the Rd strain was the least resistant. Serum bactericidal activity of anti-LOS antibody was mediated via the classical complement pathway. These findings suggest that in healthy adults, naturally acquired complement-activating anti-LOS antibodies significantly contribute to the overall serum bactericidal activity against both encapsulated and non-encapsulated strains of H. influenzae. 相似文献
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《Health policy (Amsterdam, Netherlands)》2015,119(3):307-315
The Great Recession started in Portugal in 2009, coupled with severe austerity. This study examines its impact on hospital care utilization, interpreted as caused by demand-side effects (related to variations in population income and health) and supply-side effects (related to hospitals’ tighter budgets and reduced capacity).The database included all in-patient stays at all Portuguese NHS hospitals over the 2001–2012 period (n = 17.7 millions). We analyzed changes in discharge rates, casemix index, and length of stay (LOS), using a before–after methodology. We additionally measured the association of health care indicators to unemployment.A 3.2% higher rate of discharges was observed after 2009. Urgent stays increased by 2.5%, while elective in-patient stays decreased by 1.4% after 2011. The LOS was 2.8% shorter after the crisis onset, essentially driven by the 4.5% decrease among non-elective stays. A one percentage point increase in unemployment rate was associated to a 0.4% increase in total volume, a 2.3% decrease in day cases, and a 0.1% decrease in LOS.The increase in total and urgent cases may reflect delayed out-patient care and health deterioration; the reduced volume of elective stays possibly signal a reduced capacity; finally, the shorter stays may indicate either efficiency-enhancing measures or reduced quality. 相似文献
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针对医院护理人员知识层次较低、工作强度大、碎片时间多和信息素养低的特征,结合医院图书馆的服务现状,建立了借助开源软件Drupal的护理学学科信息服务平台。通过整合医院图书馆现有馆藏资源,包括纸质、电子文献资源及网络资源等,为护理人员提供文献资源推送、标签云揭示、个性化定制等Web2.0信息服务;充分利用护理人员的碎片时间,提高护理人员信息素养及科研能力,进而最大化利用图书馆资源;探索了Web2.0环境下医院图书馆的新型服务模式。 相似文献