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Background: Periprosthetic joint infection (PJI) represents a serious complication following total knee arthroplasty. In the setting of chronic infections, the two-staged approach has traditionally been the preferred treatment method. The aim of this study was to determine the optimal period of rest between the first and second stage. Furthermore, we analyzed potentially outcome-relevant parameters, such as general and local conditions and the presence of difficult-to-treat or unidentified microorganisms, with regard to their impact on successful treatment of PJI.Patients and Methods: We performed a retrospective analysis of prospectively collected data for all patients treated for PJI at our institution. Seventy-seven patients who had undergone two-stage revision arthroplasty for PJI of the knee were included into the study. Antibiotic-loaded cement spacers were used for all patients.Results: After a median follow-up time of 24.5 months, infection had reoccurred in 14 (18.7%) patients. A prolonged spacer-retention period of more than 83 days was related to a significantly higher proportion of reinfections. Furthermore, significant compromising local conditions of the prosthetic tissue and surrounding skin, as well as repeated spacer-exchanges between first- and second-stage surgery, negatively influenced the outcome. Neither the patients'' age nor gender exerted a significant influence on the outcome regarding reinfection rates for patients'' age or gender.Conclusions: We observed the best outcome regarding infection control in patients who had undergone second-stage surgery within 12 weeks after first-stage surgery. Nearly 90% of these patients stayed free from infection until the final follow-up. An increased number of performed spacer-exchanges and a bad local extremity grade also had a negative impact on the outcome.  相似文献   
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In optical coherence tomography (OCT), the axial resolution is directly linked to the coherence length of the employed light source. It is currently unclear if OCT allows measuring thicknesses below its axial resolution value. To investigate spectral-domain OCT imaging in the super-resolution regime, we derived a signal model and compared it with the experiment. Several island thin film samples of known refractive indices and thicknesses in the range 46 – 163 nm were fabricated and imaged. Reference thickness measurements were performed using a commercial atomic force microscope. In vivo measurements of the tear film were performed in 4 healthy subjects. Our results show that quantitative super-resolved thickness measurement can be performed using OCT. In addition, we report repeatable tear film lipid layer visualization. Our results provide a novel interpretation of the OCT axial resolution limit and open a perspective to deeper extraction of the information hidden in the coherence volume.OCIS codes: (170.4500) Optical coherence tomography, (170.4470) Ophthalmology  相似文献   
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In this paper, we demonstrate the possibility to reconstruct the actual blood flow velocity vector field in retinal microvessels from dual-beam bidirectional Doppler optical coherence tomography measurements. First, for a better understanding of measured phase patterns, several flow situations were simulated on the basis of the known dual beam measurement geometry. We were able to extract the vector field parameters that determine the measured phase pattern, allowing for the development of an algorithm to reconstruct the velocity vector field from measured phase data. In a next step, measurements were performed at a straight vessel section and at a venous convergence; the obtained phase data were evaluated by means of the new approach. For the straight vessel section, the reconstructed flow velocity vector field yielded a parabolic flow. For the venous convergence, however, the reconstructed vector field deviated from a parabolic profile, but was in very good accordance with the simulated vector field for the given vessel geometry. The proposed algorithm allows predictions of the velocity vector field. Moreover, the algorithm is also sensitive to directional changes of the flow velocity as small as <1°, thereby offering insight in the flow characteristics of the non-Newtonian fluid blood in microvessels.OCIS codes: (110.4500) Optical coherence tomography, (170.2655) Functional monitoring and imaging, (280.2490) Flow diagnostics  相似文献   
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European Archives of Oto-Rhino-Laryngology - Epistaxis represents the most frequent ear, nose, throat-related emergency symptom. Seasonal variation in epistaxis incidence, with peaks during winter...  相似文献   
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World Journal of Surgery - Complications are common after ostomy surgery. Data from the Berlin OStomy Study were evaluated to determine risk factors for complications. Patients with a bowel ostomy...  相似文献   
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Patients hospitalized for an acute illness or injury are at risk of experiencing a significant loss of functioning as defined by the International Classification of Functioning, Disability and Health (ICF). The risk of a significant loss of functioning is increased in critically ill patients, in patients with complications or long-term intensive care stays, in persons with disabilities or with pre-existing chronic conditions and in the elderly. Early identification of rehabilitation needs and early start of rehabilitation can reduce healthcare costs by reducing dependence and nursing care, length of stay and prevention of disability. Two principles of rehabilitation for acute and early post-acute care can be distinguished. First, the provision of rehabilitation by health professionals who are generally not specialized in rehabilitation in the acute hospital. And second, specialized rehabilitation care provided by an interdisciplinary team. There is large variation how this specialized, typically post-acute rehabilitation care is organized, provided, and reimbursed in different countries, regions, and settings. For instance, it may be provided either in the acute hospital or in a rehabilitation or nursing setting. Most in-patients do not receive specialized rehabilitation at all during their whole stay in the acute hospital. But, it is important to point out that health professionals working in acute hospitals and who are not specialized in rehabilitation need to be able to recognize patients' needs for rehabilitation care and to perform rehabilitation interventions themselves or to assign patients to appropriate rehabilitation care settings. The principles outlined in this paper can serve as a basis for the development of clinical assessment instruments to describe and classify functioning, health and disability of patients receiving acute or early post-acute rehabilitation care.  相似文献   
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