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《The Knee》2021
BackgroundIt remains unknown how biomechanics change in posterior lateral knee using different fixation techniques in lateral meniscal allograft transplantation (MAT) during simulated toe-touch partial weight-bearing. This study aimed to compare the biomechanical effects on posterior knee between bridge and bone plug fixation in lateral MAT.MethodsIntact knee, bone bridge fixation, and bone plug fixation were tested with 500 N of axial load during knee flexion at 0°, 30°, and 60°, which simulated toe-touch partial weight-bearing. Contact area and peak pressure were assessed on posterior knee and the shift of peak pressure position were measured.ResultsOn the posterior lateral compartment, the contact mechanics of bone bridge fixation were similar to those of the intact knee (all P-values > 0.05), but its peak pressure was higher than that of intact knee at 60° (P = 0.002). For bone plug fixation, the contact area of the posterior lateral knee was significantly lower than those of intact knee and bone bridge fixation at 30° and 60° (all P-values < 0.05). The peak pressure of the posterior lateral knee was higher than that of the intact knee at all flexions and higher than that of bone bridge fixation at 30° and 60° (all P-values < 0.05). The peak pressure position of bone plug fixation shifted more laterally and posteriorly compared with intact knee and bone bridge fixation during knee flexion.ConclusionBone bridges could maintain posterior knee biomechanics better than bone plug fixation during knee bending during partial weight-bearing. 相似文献
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目的探讨以指南为依据的肿瘤放疗患者营养教育咨询方案 在降低质子重离子治疗期间显著体重下降发生率方面的有效性。方法以质子重离子治疗期间的肿瘤放疗患者为研究对象 采用历史对照研究设计 方案实施前以年月至月收治的患者为对照组 方案实施后以年月至月收治的患者为试验组。对照组在方案实施前仍实行原有的常规护理 试验组给予以指南为依据的营养教育咨询方案。结果本研究共纳入例肿瘤患者 其中对照组例 试验组例 两组平均年龄为岁和岁 %和%为头颈部肿瘤患者。放疗期间对照组平均体重下降. kg 平均体重丢失.% 显著体重下降发生率为.% 《肿瘤代谢与营养电子杂志》2021,8(1):54-57
目的探讨以指南为依据的肿瘤放疗患者营养教育咨询方案,在降低质子重离子治疗期间显著体重下降发生率方面
的有效性。方法以质子重离子治疗期间的肿瘤放疗患者为研究对象,采用历史对照研究设计,方案实施前以2016年1月至12月
收治的患者为对照组,方案实施后以2018年1月至8月收治的患者为试验组。对照组在方案实施前仍实行原有的常规护理,试验
组给予以指南为依据的营养教育咨询方案。结果本研究共纳入713例肿瘤患者,其中对照组374例,试验组339例,两组平均年
龄为54岁和53岁,45%和49%为头颈部肿瘤患者。放疗期间对照组平均体重下降0.51 kg,平均体重丢失0.75%,显著体重下降
发生率为11.2%(42例);试验组体重下降0.66 kg,平均体重丢失0.90%,显著体重下降发生率为9.4%(32例)。在控制放疗总剂量、
射线类型、肿瘤部位、同期化疗和性别的混杂因素影响后,试验组显著体重下降的风险下降了34%(OR=0.66,95%CI=0.48~0.91)。
结论以指南为依据的肿瘤放疗患者营养教咨询方案能够帮助改善质子重离子治疗期间的患者营养状态,有效降低显著体重下
降的风险。 相似文献
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Edward L. Giovannucci Leandro F. M. Rezende Dong Hoon Lee 《Journal of internal medicine》2021,290(4):789-805
The benefits of aerobic moderate-to-vigorous physical activity (MVPA) on major non-communicable diseases (NCDs) are well established. However, much less is known whether muscle-strengthening activities (i.e., resistance/weight/strength training) confer similar benefits. Herein, we conducted a narrative literature review and summarized the existing evidence from large prospective cohort studies on muscle strengthening activities and risk of major chronic diseases and mortality in adults generally free of major NCDs at baseline. Current epidemiologic evidence suggests that engagement in muscle-strengthening activities over 1–2 sessions (or approximately 60–150 min) per week was associated with reduced risk of cardiovascular disease (seven studies; approximately 20%–25% reduction), type 2 diabetes (four studies; approximately 30% reduction), cancer mortality (four studies; approximately 15%–20% reduction) as well as all-cause mortality (six studies; approximately 20%–25% reduction). For diabetes, the risk appears to lower further with even higher levels of muscle-strengthening activities, but some studies for cardiovascular and all-cause mortality suggest a reversal whereby higher levels (≥2.5 h/week) have less benefit, or are even harmful, relative to lower levels of activity. The likely mechanisms contributing to a benefit include improvement in body composition, lipid profile, insulin resistance and inflammation. The evidence supports engaging in 1–2 sessions (up to 2.5 h) per week, preferably performed complementary to the recommended levels of aerobic MVPA. Although data are limited, caution is suggested for training exceeding 2.5 h per week. Further studies are required to better understand the influence of frequency, duration and intensity of muscle-strengthening activities on major NCDs and mortality in diverse populations. 相似文献
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B. Kowall N. Lehmann A.A. Mahabadi S. Moebus R. Erbel K.H. Jöckel A. Stang 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(3):228-235
Background and aims
There is controversy on the potentially benign nature of metabolically healthy obesity (MHO), i.e., obese persons with few or no metabolic abnormalities. So far, associations between MHO and coronary artery calcification (CAC), a measure of subclinical atherosclerosis, have mainly been studied cross-sectionally in Asian populations. We assessed cross-sectional and longitudinal MHO CAC associations in a Caucasian population.Methods and results
In the Heinz Nixdorf Recall Study, a population-based cohort study in Germany, CAC was assessed by electron-beam tomography at baseline and at 5-year follow-up. For cross-sectional and longitudinal analyses, we included 1585 participants free of coronary heart disease at baseline, with CAC measurements at baseline and at follow-up, and with either normal weight (BMI 18.5–24.9 kg/m2) or obesity (BMI ≥30.0 kg/m2) at baseline. We used four definitions of MHO. In our main analysis, we defined obese persons as metabolically healthy if they met ≤1 of the NCEP ATP III criteria for the definition of the metabolic syndrome – waist circumference was not taken into account because of collinearity with BMI.Persons with MHO had a higher prevalence of CAC than metabolically healthy normal weight (MHNW) persons (prevalence ratio = 1.59 (95% confidence interval 1.38–1.84) for the main analysis). Persons with MHO had slightly larger odds of CAC progression than persons with MHNW (odds ratios ranged from 1.17 (0.69–1.99) to 1.48 (1.02–2.13) depending on MHO definition and statistical approach).Conclusion
Our analyses on MHO CAC associations add to the evidence that MHO is not a purely benign health condition. 相似文献18.
Ramya C. Mosarla Muthiah Vaduganathan Arman Qamar Javid Moslehi Gregory Piazza Robert P. Giugliano 《Journal of the American College of Cardiology》2019,73(11):1336-1349
Patients with active cancer are at an increased risk of arterial and venous thromboembolism (VTE) and bleeding events. Historically, in patients with cancer, low molecular weight heparins have been preferred for treatment of VTE, whereas warfarin has been the standard anticoagulant for stroke prevention in patients with atrial fibrillation (AF). More recently, direct oral anticoagulants (DOACs) have been demonstrated to reduce the risk of venous and arterial thromboembolism in large randomized clinical trials of patients with VTE and AF, respectively, thus providing an attractive oral dosing option that does not require routine laboratory monitoring. In this review, we summarize available clinical trial data and guideline recommendations, and outline a practical approach to anticoagulation management of VTE and AF in cancer. 相似文献
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X.‐X. Shi H. Zhang M. Chen Y.‐D. Zhang M.‐F. Zhu M.‐J. Zhang F.‐Q. Li S. Wratten W.‐W. Zhou C. Mao Z.‐R. Zhu 《Insect molecular biology》2019,28(2):253-263
Although sphingomyelins known to be are lipid constituents of the plasma membrane in vertebrates, much remains obscure about the metabolism of sphingomyelins in insects. With ultra performance liquid chromatography‐time‐of‐flight‐tandem mass spectrometry analysis, we revealed for the first time that sphingomyelins are abundant in Nilaparvata lugens (Stål), the brown planthopper (BPH), and their biosynthesis is carried out by sphingomyelin synthase‐like protein 2 (SMSL2), which is homologous to sphingomyelin synthase‐related protein (SMSr). Unlike other insect species, high concentrations of sphingomyelins rather than ceramide phosphoethanolamines exist in the BPH. Two putative genes, which are homologous to SMSr, are named Nilaparvata lugens SMS‐like 1 (NlSMSL1) and 2 (NlSMSL2). Knockdowns of both NlSMSL2 and NlSMSL1 were conducted but only the first decreased concentrations of sphingomyelins in the BPH, indicating that NlSMSL2 plays a role in the biosynthesis of sphingomyelins. Real‐time quantitative PCR analysis revealed both NlSMSL1 and NlSMSL2 are highly expressed in BPH adults, with NlSMSL1 specifically highly expressed in reproductive organs (ovaries and testes) whereas NlSMSL2 was highly expressed in the malpighian tubules. The knockdown of NlSMSL1 or NlSMSL2 increased BPH female body weight but not that of males, suggesting sex‐specific roles for SMSLs in influencing BPH body weight. The results suggest that NlSMSL2 catalyses the synthesis of sphingomyelins and maintains female BPH body weight through alteration of sphingolipid content. 相似文献
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