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Obesity Surgery - Previous studies have shown that bariatric surgery reduces the risk of cardiovascular outcomes. Less is known about the effects of bariatric surgery on psychiatric disorders. This...  相似文献   
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Background

Torsional malalignment syndrome (TMS) is a well defined condition consisting of a combination of femoral antetorsion and tibial lateral torsion. The axis of knee motion is medially rotated. This may lead to patellofemoral malalignment with an increased Q angle and chondromalacia, patellar subluxation and dislocation. Conservative management is recommended in all but the most rare and severest cases. In these cases deformity correction requires osteotomies at two levels per limb.

Materials and methods

From 1987 to 2002 in our institution three patients underwent double femoral and tibial osteotomy for TMS bilateral correction (12 osteotomies). All patients were reviewed at mean follow-up of 16 years.

Results

At final follow-up no patients reported persistence of knee or hip pain. At clinical examination both lower limbs showed a normal axis and a normal patella anterior position. Pre-operative femoral version measurement showed an average hip internal rotation of 81.5° (range 80°–85°) and average hip external rotation of 27.2° (10°–40°). Thigh–foot angle measurement showed an average value of 38.6° (32°–45°). At final follow-up femoral version measurement showed an average hip internal rotation of 49° (range 45°–55°) and average hip internal rotation of 44.3° (20°–48°) (Figs. 1, 2, 3, 4, 5, 6). Thigh–foot angles measurement showed an average value of 21.6° (18°–24°) outward.

Conclusion

We recommend a clinical, radiographical and CT scan evaluation of all torsional deformity. In cases of significant deformity, internally rotating the tibia alone is not sufficient. Ipsilateral outward femoral and inward tibial osteotomies are our current recommendation for TMS, both performed at the same surgical setting.  相似文献   
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The environmental condition in which the Royal Malaysian Airforce is currently operating its aircraft is prone to corrosion. This is due to the high relative humidity and temperature. With most of its aircraft being in the legacy aircraft era, the aircraft’s main construction consists of the aluminium 2024 material. However, this material is prone to corrosion, thus reducing fatigue life and leading to fatigue failure. Using the concept of either Safe Life or Damage Tolerance as its fatigue design philosophy, the RMAF adopts the Aircraft Structure Integrity Program (ASIP) to monitor its structural integrity. With the current problem of not having the structural limitation on corrosion-damaged structure, the RMAF has embarked on its fatigue testing method. Finite Element (FE) studies and flight tests were conducted, and the outcome is summarized. The conclusion is that the longeron tested on the aircraft can withstand the operational load, and its yield strength is below the ultimate yield strength of the material. These research outcomes will also enhance the ASIP for other aircraft platforms in the RMAF fleet for its structure life assessment or service life extension program.  相似文献   
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SARS-CoV-2 (Severe Acute Respiratory Syndrome-Coronavirus 2) has accumulated multiple mutations during its global circulation. Recently, three SARS-CoV-2 lineages, B.1.1.7 (501Y.V1), B.1.351 (501Y.V2) and B.1.1.28.1 (P.1), have emerged in the United Kingdom, South Africa and Brazil, respectively. Here, we have presented global viewpoint on implications of emerging SARS-CoV-2 variants based on structural–function impact of crucial mutations occurring in its spike (S), ORF8 and nucleocapsid (N) proteins. While the N501Y mutation was observed in all three lineages, the 501Y.V1 and P.1 accumulated a different set of mutations in the S protein. The missense mutational effects were predicted through a COVID-19 dedicated resource followed by atomistic molecular dynamics simulations. Current findings indicate that some mutations in the S protein might lead to higher affinity with host receptors and resistance against antibodies, but not all are due to different antibody binding (epitope) regions. Mutations may, however, result in diagnostic tests failures and possible interference with binding of newly identified anti-viral candidates against SARS-CoV-2, likely necessitating roll out of recurring “flu-like shots” annually for tackling COVID-19. The functional relevance of these mutations has been described in terms of modulation of host tropism, antibody resistance, diagnostic sensitivity and therapeutic candidates. Besides global economic losses, post-vaccine reinfections with emerging variants can have significant clinical, therapeutic and public health impacts.  相似文献   
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