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《The Journal of arthroplasty》2019,34(9):2022-2029
BackgroundCementless metaphyseal implant fixation of revision total knee arthroplasty has encouraging early results. We analyzed midterm results and implant survival of osteointegrative augments in Anderson Orthopedic Research Institute (AORI) type 2a, 2b, and 3 defects. Reasons for implant failure were explored and the potential for anatomic joint line reconstruction evaluated.MethodsSixty-seven consecutive patients (68 revision total knee arthroplasties) received cementless metaphyseal sleeves between 2011 and 2014. The mean follow-up was 5.0 years, mean age was 68.5 years, and mean body mass index was 31.4 kg/m2. The clinical and radiographic results were determined using established scoring systems. Additionally, the survival rate was calculated and reasons for failure were analyzed.ResultsIn 2 patients (4.3%), sleeves had to be removed early postoperatively for deep infection after second-stage reimplantation. With continuously functioning remaining implants, the aseptic survival rate was 93.6%. Cleared up for initial technical issues due to poor bone quality, it is as high as 98%. The scores remained to be significantly improved by 64.8 points (Western Ontario and McMaster Universities Osteoarthritis Index) and 25.8 points (Knee Society score) (P < .001). In 10 patients (29.4%), diaphyseal radiolucencies were observed without suspicion of loosening. The mean joint line was noted to be 0.36 mm lower to the anatomic level.ConclusionAt a mean follow-up of 5.0 years, cementless osteointegrative sleeves for metaphyseal fixation in AORI 2a, AORI 2b, and AORI 3 defects yielded continuous implant fixation even in cases with preceding revisions. The cleared up aseptic survival rate was 98% at 5 years. The modular sleeve design allowed joint line reconstruction near the anatomic level.  相似文献   
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《Injury》2019,50(4):1000-1003
AimThe screw length is important to achieve a stable fixation for medial malleoli fractures. We aimed to evaluate the optimal screw length for different age groups in surgically treated medial malleoli fractures. The second aim was to identify the utility of the distance of epiphyseal scar to joint line or joint line to medullary space for assessment of screw length.Material method368 X-rays and computed tomography (CT) images of ankle joints were retrospectively evaluated for optimal screw length, epiphyseal scar to joint line distance, joint to medullary space distance. The mean screw length for each decade was calculated. The correlations of screw length with age, screw length with distance of epiphyseal scar to joint line, and screw length with distance of joint line to medullary space were evaluated.ResultsThe optimal screw length was obviously decreased in patients in 61–70 and >70 years old group (p = 0.002). As the distance of epiphyseal scar from joint line was increased, the optimal length of screw was also increased (p = 0.001). The distance of epiphyseal scar from joint line was decreased by age (p = 0.011).ConclusionThe optimal screw length was decreased by age and the epiphyseal scar to joint line distance could be a clue for optimal screw length in medial malleoli fractures.  相似文献   
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《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity.  相似文献   
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《The Journal of arthroplasty》2022,37(9):1793-1798
BackgroundDespite numerous advances in the implant design and surgical technique, improvement in patient satisfaction following total knee arthroplasty (TKA) has plateaued. Various TKA alignment strategies have been introduced that impact the coronal positioning of the tibial component relative to the native joint line. This study aims to analyze if postoperative variance of the joint line from preoperative native alignment is correlated with changes in patient-reported outcomes following primary TKA.MethodsA retrospective review of an academic center’s patient population identified all primary TKAs between 2013 and 2021 with full-length, standing radiographs and patient-reported outcome measures (PROMs) data. These measures included the Knee injury and Osteoarthritis Outcome Score for Joint Replacement, Patient-Reported Outcome Measurement Information System, and Veterans RAND 12 scores. Preoperative and postoperative radiographic measurements for hip-knee angle, tibia-metaphyseal angle, tibial-axis orientation angle, and joint-line obliquity angle were recorded. Three-month, 1-year, and 2-year PROM scores were correlated with the change in degrees for each of the angles using a Spearman’s correlation. A Mann-Whitney U-test was used to compare angular changes with a change in PROM scores.ResultsOne hundred and ninety nine patients (204 knees) with a mean age of 67 years were included. Average follow-up was 23 months. Three-month, 1-year, and 2-year follow-up rates were 93%, 64%, and 34%, respectively. Improvements were seen across all PROMs regardless of an angular change.ConclusionThere were no clear correlations between PROMs and variation in joint line obliquity in the coronal plane. These data suggest that the magnitude of the variation in coronal tibial alignment from native alignment does not impact PROMs. Further study is indicated to correlate an angular change with functional measures.  相似文献   
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目的:研究体外缺氧对乳腺癌细胞系MCF7浸润能力及其细胞表面黏附分子E-cadherin和细胞骨架蛋白犤细胞角蛋白(cytokeratin)、波形蛋白(vimentin)犦表达的影响。方法:模拟体外缺氧环境,观察缺氧对乳腺癌细胞MCF7浸润穿透Matrigel的能力;以及采用半定量RT-PCR检测细胞表面黏附分子E-cadherin和cytokeratin、vimentin表达情况。结果:缺氧状态下MCF7细胞的浸润能力明显增强;且在缺氧条件下E-cadherin基因表达下降、cytokeratin、vimentin基因表达升高。结论:缺氧状态下MCF7细胞转移能力和其表面的E-cadherin基因、cytokeratin、vimentin基因表达存在一定关系。  相似文献   
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Placement of tunnelled dialysis lines is effective using ultrasoundand fluoroscopic guidance [1] and has a higher success ratethan ‘blind’ insertion [2]. After the ultrasound guided access into a neck vein, wires andcatheters are guided in to a suitable position in the  相似文献   
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