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31.

Objectives

Using finite element analysis and biomechanical tests, the biomechanical behaviors of Medial Sustainable Nail (MSN) and Proximal Femoral Nail Antirotation (PFNA) were compared for the fixation of fracture type of AO/OTA 31-A2.3.

Methods

Finite element software Abaqus 6.14 was used to conduct axial loading of 2100?N and we analyzed the von Mises stress distribution and the model displacement of two implant models. Biomechanical tests were separately conducted in the axial stiffness test and axial cyclical loading test on a mechanical testing machine.

Results

The results indicate that von Mises stress of MSN was lower than that of PFNA, and the model displacement in the MSN group was lower than that in the PFNA group. In the axial stiffness tests, MSN group was stiffer than PFNA construct. With respect to the axial load to ultimate failure, the PFNA construct exhibited higher loads exceeding 4000?N while the MSN construct withstood 3313.8?±?92.8?N. Specifically, F10mm was 2178.6?±?133.2?N of the MSN group and 1822.6?±?93.1?N of the PFNA group (P?=?0.001). Additionally, X2100N was 9.8?±?0.5?mm of the MSN group and 11.7?±?0.7?mm of the PFNA group (P?=?0.002). The MSN group exhibited superior performances in terms of the mean value of the vertical displacement, frontal rotation angle, and lateral rotation angle.

Conclusions

The results indicated that the MSN construct might exhibit a better biomechanical performance when compared with that of the PFNA in reducing displacement and anti-varus in fracture type of AO/OTA 31-A2.3.  相似文献   
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Felbamate is an anticonvulsant used in the treatment of epilepsy. In this study, we investigated the antidepressant‐like actions of felbamate in mice. The effects of felbamate were first assessed using the forced swimming test (FST) and tail suspension test (TST), and then investigated in the chronic unpredictable mild stress (CUMS) and chronic social defeat stress (CSDS) models of depression. The changes in the hippocampal brain‐derived neurotrophic factor (BDNF) signaling cascade after chronic stress and felbamate treatment were also examined. It was found that felbamate exhibited antidepressant‐like activities in the FST and TST without affecting the locomotor activity of mice. Felbamate was also effective in both the CUMS and CSDS models of depression. Moreover, felbamate administration fully restored the decreased hippocampal BDNF signaling pathway in both the CUMS‐stressed and CSDS‐stressed mice. Collectively, felbamate has antidepressant‐like actions in mice involving the hippocampal BDNF system.  相似文献   
34.
Although patients with rosacea often consult dermatologists for dietary factors that might be related to their skin disorders, few studies have been conducted to research the relationship between rosacea and dietary factors. The purpose of this study was to evaluate the potential relationship between rosacea and diet among the large Chinese population with rosacea, which would provide dietary guidelines for patients with rosacea. A multicenter case–control study was conducted. The feeding frequency 2 years before the occurrence of rosacea was collected by standardized questionnaires. Multiple logistic regression analysis was used to calculate risks related to the diet. One thousand three hundred and forty‐seven patients with rosacea and 1290 controls were enrolled in our study. We found that high‐frequency intake of fatty food and tea presented a positive correlation with rosacea, while high‐frequency dairy product intake showed significant negative correlation with rosacea. Sweet food, coffee and spicy food appeared to be independent of any subset of rosacea in our study. However, high‐frequency dairy product intake showed a borderline beneficial effect on rosacea severity. We further analyzed the correlation between diet and the subtype of rosacea. We found that high‐frequency fatty intake was associated with erythematotelangiectatic rosacea (ETR) and phymatous rosacea, while high‐frequency tea intake was only associated with ETR. In addition, high‐frequency dairy product intake showed negative correlations with ETR and papulopustular rosacea. Rosacea is associated with some dietary factors, and our study is valuable in establishing dietary guidelines to prevent and improve rosacea.  相似文献   
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Colorectal cancer (CRC) is one of the top three most deadly cancers despite using chemotherapy based on oxaliplatin or irinotecan combined with targeted therapy. Chiauranib has recently been identified to be a promising anticancer candidate with impressive efficacy and safety. However, the role and molecular mechanisms of Chiauranib in the treatment of CRC remain to be elucidated. Our study shows that Chiauranib inhibits cell proliferation and induces apoptosis in KRAS wild-type CRC cells in a dose- and time-dependent manner, but not mutation ones. Meanwhile, Chiauranib increases ROS production in KRAS wild-type CRC cells. Moreover, Chiauranib selectively suppresses KRAS wild-type CRC cells growth in vivo. Mechanistically, Chiauranib inhibits KRAS wild-type CRC cells by triggering ROS production via activating the p53 signaling pathway. Further, KRAS mutation CRC cells are resistant to Chiauranib by increasing Nrf2 to stably elevate the basal antioxidant program and thereby lower intracellular ROS induced by Chiauranib. Our findings provide the rationale for further clinical evaluation of Chiauranib as a therapeutic agent in treating KRAS wild-type CRC.  相似文献   
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目的 探讨综合医院发热门诊应对新型冠状病毒感染肺炎的应急管理方法及效果。 方法 加强发热门诊的管理,包括优化发热预检分诊工作流程、合理布局发热门诊、修订发热门诊工作职责与流程指引、合理调配人力资源、加强相关人员培训、严格落实院感防控措施、提供后勤保障、加强健康宣教与管理。 结果 接诊患者13 761例次,采集咽拭子591例次,静脉输液11 973例次,氧气吸入998例次。 结论 加强综合医院发热门诊管理,能有效提高护理人员对新型冠状病毒肺炎疫情的应对能力,保障护理安全。  相似文献   
40.
目的 分析山西营养与慢性病家庭队列人群BMI与总死亡率的关系。方法 以"2002年中国居民营养与健康状况调查"山西省调查人群为基线建立队列,于2015年12月至2016年3月对研究对象进行随访调查,对逝者进行死因回顾调查。2002年基线信息完整的≥ 18岁研究对象7 007人,随访到5 360人,随访率为76.5%。将研究对象按BMI分为8组,计算死亡率,以死亡率最低组作为参照,采用Cox比例风险回归模型估计全人群、分性别、年龄(≥ 60岁、<60岁)的各组死亡风险比(HR)及95% CI,模型调整基线年龄、性别、吸烟、饮酒、文化程度等因素,并进行敏感性分析。结果 共随访67 129人年,平均随访12.5年,死亡615人,队列总死亡率为916/10万人年。BMI为26.0~27.9 kg/m2组死亡率最低,以该组为参照组,多因素调整后,BMI<18.5、18.5~19.9、22.0~23.9和≥ 30.0 kg/m2组的死亡风险明显升高,调整HR值(95% CI)分别为1.90(1.26~2.86)、1.68(1.15~2.45)、1.49(1.08~2.06)和1.72(1.07~2.76)。对于≥ 60岁老年人,BMI<18.5 kg/m2组的死亡风险明显升高,调整HR值(95% CI)为1.94(1.20~3.15)。结论 BMI ≤ 19.9、22.0~23.9及≥ 30.0 kg/m2均会增加全因死亡风险。除关注肥胖外,低体重营养不良造成的老年人高死亡风险应特别引起重视。  相似文献   
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