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51.
Background:The purpose of this study was to evaluate the clinical outcomes and complications of displaced proximal humeral fractures treated with proximal humeral internal locking system (PHILOS) plate fixation via a deltoid interfascicular (DI) vs a deltopectoral (DP) approach.Methods:This prospective case-control study was conducted with patients admitted to our hospital from May 2015 to June 2018 who suffered from unilateral displaced proximal humerus fractures. Patients were treated with PHILOS plate fixation via a DI (DI group) or DP approach (DP group). The clinical outcomes and complication data were collected for comparison between the 2 groups. The patients were followed up at 3, 6, and 12 months; and every 6 months thereafter. The patients’ functional recoveries were evaluated according to the normalized Constant-Murley score, range of motion of the shoulder (flexion, abduction, external/internal rotation) and disabilities of the arm, shoulder and hand score.Results:A total of 77 patients, followed for an average of 15 ± 2.2months (range, 12–21), were enrolled (36 in DI group and 41 in DP group) for final analysis. No significant differences in age, sex, affected side, fracture type, injury mechanism or time from injury to operation were found between the 2 groups (all P > .05). The incision length, intra-operative blood loss, and duration of operation in the DI group were significantly less than those in the DP group, respectively (all P < .05). The functional outcomes assessed by the normalized Constant-Murley score and range of motion of flexion and internal rotation in the DI group were superior to those in the DP group at 3 and 6months after the operation (P < .05); however, no significant differences were observed at the 12-month and subsequent follow-ups (all P > .05). There was no significant difference in the range of shoulder external rotation and abduction during the postoperative follow-ups (P > .05). At the last follow-up, the mean disabilities of the arm, shoulder, and hand score was 14.0 (6.6) points in the DI group and 14.4 (6.9) points in the DP group (P = .793). Complications occurred in 1 patient in the DI group and 8 patients in the DP group (P = .049).Conclusion:The current study demonstrates that DI approach is a safe and effective alternative for the treatment displaced proximal humerus fractures. The DI approach rather than DP approach was recommended when lateral and posterior exposure of the proximal humerus is required, especially when fixed with PHILOS plate. 相似文献
52.
目的 探讨在全程分娩管理模式下,为孕产妇提供促宫颈成熟与引产服务的可行性。方法 选择2018年1月1日至2020年12月31日,在南京大学医学院附属鼓楼医院接受待产、分娩到产后康复(LDRP)一体化全程分娩管理模式(以下简称为LDRP管理)的848例孕产妇为研究对象。根据孕产妇进入产房时是否进入自然产程,将其分为自然临产组(n=441)和引产组(n=407)。采用回顾性分析法,对2组孕产妇的一般临床资料,如分娩年龄、孕次、孕龄、妊娠并发症,以及母儿结局进行比较。本研究遵循的程序符合2013年修订的《世界医学协会赫尔辛基宣言》的要求,并经过南京大学医学院附属鼓楼医院伦理委员会审核批准(审批文号:201702001)。结果 (1)2组孕产妇分娩年龄、孕次和高龄孕产妇所占比例比较,差异无统计学意义(P>0.05)。2组孕产妇分娩孕龄、经产妇占比、早产率、缩宫素使用率、分娩时长比较,差异有统计学意义(P<0.05)。(2)引产组孕产妇均使用前列腺素类药物促宫颈成熟或缩宫素进行引产,其中使用地诺前列酮栓、米索前列醇、缩宫素、地诺前列酮栓+米索前列醇分别为26.5%(108/407)、... 相似文献
53.
54.
Photocatalytic water splitting has garnered tremendous attention for its capability to produce clean and renewable H2 fuel from inexhaustible solar energy. Until now, most research has focused on scarce pure water as the source of H2, which is not consistent with the concept of sustainable energy. Hence, the importance of photocatalytic splitting of abundant seawater in alleviating the issue of pure water shortages. However, seawater contains a wide variety of ionic components which have unknown effects on photocatalytic H2 production. This work investigates photocatalytic seawater splitting conditions using environmentally friendly amorphous carbon nitride (ACN) as the photocatalyst. The individual effects of catalyst loading (X1), sacrificial reagent concentration (X2), salinity (X3), and their interactive effects were studied via the Box–Behnken design in response surface modeling towards the H2 evolution reaction (HER) from photocatalytic artificial seawater splitting. A second-order polynomial regression model is predicted from experimental data where the variance analysis of the regressions shows that the linear term (X1, X2), the two-way interaction term X1X2, and all the quadratic terms (X12, X22, X23) pose significant effects towards the response of the HER rate. Numerical optimization suggests that the highest HER rate is 7.16 µmol/h, achievable by dosing 2.55 g/L of ACN in 45.06 g sea salt/L aqueous solution containing 17.46 vol% of triethanolamine. Based on the outcome of our findings, an apparent effect of salt ions on the adsorption behavior of the photocatalyst in seawater splitting with a sacrificial reagent has been postulated. 相似文献
55.
Dongtong Yang Sen Tang Yongtao Hu Alexander Nikitin Qingyuan Wang Yongjie Liu Lang Li Chao He Yan Li Bo Xu Chong Wang 《Materials》2022,15(14)
The very high cycle fatigue (VHCF) failure of in-service components is mainly caused by the vibration of thin-wall elements at a high frequency. In this work, a novel model of ultrasonic fatigue test was developed to test thin-wall material in bending up to VHCF with an accelerated frequency. The theoretical principle and finite element analysis were introduced for designing a sample that resonated at the frequency of 20 kHz in flexural vibration. In the advantage of the second-order flexural vibration, the gauge section of the sample was in the pure bending condition which prevented the intricate stress condition for thin-wall material as in the root of cantilever or the contact point of three points bending. Moreover, combining the constraint and the loading contact in one small section significantly reduced heating that originated from the friction at an ultrasonic frequency. Both strain gauge and deflection angle methods were applied to verify the controlling of stress amplitude. The fractography observation on Ti6Al4V samples indicated that the characterized fracture obtained from the novel model was the same as that from the conventional bending test. 相似文献
56.
Jadwiga Kryczyk-Kozio Ewelina Prochownik Anna Baewska-Gruszczyk Marian Sowiaczek Qian Sun Lutz Schomburg Ewa Ochab Mirosaw Bartyzel Pawe Zagrodzki 《Nutrients》2022,14(14)
The impact of selenium on the course of Hashimoto’s thyroiditis (HT) was mainly assessed by monitoring the titer of antithyroid autoantibodies in most of the studies conducted hitherto. On the other hand, the imbalance in activity of T cells such as Th1, Th2, Th17, and Treg may be relevant in the pathogenesis of this disease. Hence, the assessment of changes in the secretion of cytokines by these cells during selenium supplementation in patients with HT seems to be an important issue and was the main goal of this study. A further aim was to search for correlations among these cytokines, as well as markers of thyroid function, selenium/iodine status in the body, and other biochemical parameters. The group of 29 women with newly diagnosed Hashimoto’s thyroiditis was supplemented with selenium in a dose of 100 µg/day for 6 months. Immunological parameters: interferon γ, tumor necrosis factor α, chemokine CXCL10, interleukin 4, interleukin 1β, interleukin 17, transforming growth factor β, and C-reactive protein, as well as selenium status parameters were determined in serum twice, i.e., before and after supplementation. Selenium supplementation was associated with a change in the production of two cytokines: interferon γ and interleukin 1β, for which a decrease and an increase in concentration were observed, respectively. The partial least squares (PLS) model revealed the presence of many relevant correlations among analyzed parameters. The stage of HT development, degree of thyroid dysfunction, and selenium supplementation of diet are interdependent factors which shape the profile of some cytokines secreted by cells participating in the autoimmunity process. 相似文献
57.
58.
目的 探讨尿道下裂患儿尿道板组织和尿道部皮肤组织中雌激素受体(ER)和微血管密度(MVD)的表达及意义.方法 选取2013年6月-2015年1月天津儿童医院收治的尿道下裂手术患儿30例,术中分别取部分尿道板和尿道部皮肤组织,检测不同组织中ER及MVD的表达及分布情况.结果 2组均检测到ER及MVD的表达.尿道板组织与尿道部皮肤组织中ER表达水平比较差异无统计学意义(P>0.05),尿道板组织中MVD低于尿道部皮肤组织(P<0.05).结论 尿道板组织和尿道部皮肤组织ER含量接近,可能与尿道发育异常有关;尿道板组织中存在微血管分布,为保留尿道板的尿道成形术提供了理论依据;尿道板组织内MVD显著降低,可能为术后发生尿瘘的原因之一. 相似文献
59.
我科20ll-12-2012-11对32例经鼻内镜和鼻窦冠状位CT检查确诊为慢性鼻一鼻窦炎伴(或不伴)鼻息肉患者行低温等离子辅助下重塑钩突的内镜鼻窦手术,疗效满意,报告如下。 相似文献
60.
目的设计一种骨骺生长滑动钢板,在有效固定骨折的同时,又能减轻对骨骼纵向生长的抑制,减少肢体畸形的发生,并通过动物实验进行评估。方法根据青少年股骨髁部的解剖特点设计出适用于青少年儿童股骨髁部骨折的内固定滑动钢板。动物实验选24只健康幼年山羊,8只山羊为正常对照组,余16只为钢板内固定组,其中右后肢采用普通钢板固定,左后肢采用滑动钢板固定。术后1 d,1、2、3、6个月5个时相点对所有山羊双侧股骨进行X线摄片检查,并通过fPAX系统测量左右股骨的长度进行统计学分析。结果正常对照组山羊双侧股骨在5个时相点长度统计学均无显著性差异,钢板内固定组,在术后1 d、1个月双侧股骨长度统计学均无显著性差异,在术后3、6个月双侧股骨长度统计学存在显著性差异,滑动钢板侧股骨长度明显长于普通钢板侧,股骨长度术后1、2、3、6个月分别与术后1 d增长的数值进行比较分析,普通钢板侧和正常对照组右侧股骨长度存有显著性差异,滑动钢板侧和正常对照组左侧股骨长度无显著性差异。结论本组实验证实滑动钢板在动物体内随骨骺的生长过程中可自动延长,符合发育期青少年儿童骨骺生长的生理特点,可进行进一步的研究。 相似文献