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1.
BackgroundAnteriorly-loaded walking is common in many occupations and may increase fall risk. Dynamic gait stability, defined by the Feasible Stability Region (FSR) theory, quantifies the kinematic relationship between the body’s center of mass (COM) and base of support (BOS). FSR-based dynamic gait stability has been used to evaluate the fall risk.Research questionHow does front load carriage affect dynamic gait stability, step length, and trunk angle among young adults during treadmill walking?MethodsIn this between-subject design study, 30 healthy young adults were evenly randomized into three load groups (0%, 10%, or 20% of body weight). Participants carried their assigned load while walking on a treadmill at a speed of 1.2 m/s. Body kinematics were collected during treadmill walking. Dynamic gait stability (the primary variable) was calculated for two gait events: touchdown and liftoff. Step length and trunk angle were measured as secondary variables. One-way analysis of variance was conducted to detect any group-related differences for all variables. Post-hoc analysis with Bonferroni correction was performed when main group differences were found.ResultsNo significant differences but medium to large effect sizes were found between groups for dynamic gait stability at touchdown (p = 0.194, η2 = 0.114) and liftoff (p = 0.122, η2 = 0.139). Trunk angle significantly increased (indicating backward lean) with the front load at touchdown (p < 0.001, η2 = 0.648) and liftoff (p < 0.001, η2 = 0.543). No significant between-group difference was found related to the step length (p = 0.344, η2 = 0.076).SignificanceCarrying a front load during walking significantly alters the trunk orientation and may change the COM-BOS kinematic relationship and, therefore, fall risk. The findings could inform the design of future studies focusing on the impact of anterior load carriage on fall risk during different locomotion.  相似文献   
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目的  探讨Hsa-miR-4282在肝癌细胞系SMMC-7721中的表达及其对细胞生长的影响。方法 采用实时荧光定量PCR法检测Hsa-miR-4282在人正常肝上皮细胞系HL-7702和人肝癌细胞系MHCC97-H、SMMC-7721,以及 20例肝癌组织及其相应癌旁组织中的表达。采用瞬时转染法将Hsa-miR-4282 mimics(上调组)和Hsa-miR-4282 inhibitor(下调组)分别转染肝癌SMMC-7721细胞,上调组和下调组分别设置相应阴性对照组。转染后采用MTT法检测细胞增殖能力,平板克隆形成实验检测细胞克隆形成能力,流式细胞仪检测细胞凋亡能力。结果 Hsa-miR-4282在肝癌组织、肝癌细胞MHCC97-H及肝癌细胞SMMC-7721中的表达均低于癌旁组织及正常肝细胞HL-7702(P<0.05)。MTT实验结果显示,Hsa-miR-4282上调后肝癌SMMC-7721细胞的OD值低于其阴性对照组,而下调后OD值高于其阴性对照组 (P<0.05)。平板克隆形成实验显示,下调组的细胞克隆数高于其阴性对照组[(240±7) 个 vs (191±10) 个,P=0.005)],而上调组细胞克隆数低于基阴性对照组[(146±10) 个 vs (193±12) 个,P=0.013)]。流式细胞仪检测结果显示,Hsa-miR-4282上调组细胞凋亡率较其阴性对照组升高[(23.89±1.89)% vs(16.6±1.14)%,P=0.009)],下调组细胞凋亡率较期阴性对照组降低[(14.98±0.46)% vs (17.79±0.73)%,P=0.010]。结论 Hsa-miR-4282上调可抑制肝癌SMMC-7721细胞增殖,促进细胞凋亡,可能与肝癌的发病机制有关。  相似文献   
3.
BackgroundRocker sole (RS) shoes have been linked to impaired postural control. However, which features of RS design affect balance is unclear.Research questionWhich RS design features affect standing balance and gait stability?MethodsThis study utilized an intervention and cross-over design. Twenty healthy young adults (10 males and 10 females) participated in this study. Standing balance and gait stability were measured using a single force platform and three-dimensional motion analysis system, respectively. The experimental conditions included the control shoe and five RS shoes in the combination of apex position (%) and apex angle (degree) for RS50-95, RS60-95, RS70-95, RS60-70, and RS60-110. The main outcome measures were the area surrounding the maximal rectangular amplitude, mean path length, average displacement of the center of pressure along the lateral and anterior/posterior directions, and maximal center of pressure excursion as the standing balance and lateral margin of stability as the gait stability. Statistical analyses were conducted using a two-way split-plot analysis of variance with repeated measures (with RS design as the within-subject factor and sex as the between-subject factor) and the Bonferroni post hoc test (α = .05).ResultsRegarding the mean path length, RS60-70 was significantly longer than the control shoe, and it showed a significantly increased lateral margin of stability. Thus, RS60-70 was shown to affect standing balance, limit of stability, and gait stability of the frontal plane during gait.SignificanceThese results suggest that the apex angle of the RS design feature affects standing balance and gait stability, and RS60-70 is detrimental to stability. Therefore, when RS with a small apex angle is prescribed, it is necessary to consider the patient’s balance ability.  相似文献   
4.
《Foot and Ankle Surgery》2020,26(2):193-197
BackgroundThe aim of this study was to compare the radiographic and functional results between fixation and non-fixation in the Cotton osteotomy for the treatment of adult acquired flatfoot.MethodsA retrospective, case-controlled study of consecutive stage IIB posterior tibial tendon dysfunction (PTTD) patients treated with the same bony reconstructive surgery including cotton osteotomy between 2013 and 2017. Meary’s angle, the medial arch sag angle (MASA), and medial cuneiform cobb angle (MCCA) were evaluated pre-operation, at first weight bearing after surgery, and 12 months post operation.ResultsForty feet were included in the study. The cotton osteotomy utilized screw fixation (n = 20) or non-fixation technique (n = 20). No significant differences between groups were found in pre-operative and follow-up radiographic parameters, union rate, and functional results.ConclusionThe non-fixation with press fit technique is a reliable procedure for Cotton osteotomy and as effective as screw fixation.Level of evidenceLevel III, case control study  相似文献   
5.
目的:探讨负压创面治疗技术(Vacuum assisted closure,VAC)结合游离植皮治疗儿童大面积皮肤缺损疗效及对患儿生活质量的影响。方法:选取2015年2月-2019年2月笔者医院收治的60例大面积皮肤缺损患儿作为研究对象,按照随机数表法分为干预组和对照组,每组30例。对照组采用游离植皮术治疗,干预组在对照组的基础上结合VAC治疗,以皮片成活时间、皮片成活率、换药次数及住院天数评估疗效,以长海痛尺分级法评估患儿疼痛等级,以抑郁自评量表(Self-rating depression scale,SDS)、焦虑自评量表(Self-rating anxiety scale,SAS)评估患儿心理状态,以术后不良反应发生率评估患儿预后情况,以自制生活质量表评估患儿生活质量水平。结果:干预组患儿皮片成活时间、换药次数与住院天数均小于对照组,差异有统计学意义(P<0.05)。干预组患儿皮片成活率为93.33%高于对照组的76.67%,差异有统计学意义(P<0.05)。干预组治疗后疼痛感、SDS与SAS评分低于治疗前,且低于对照组,差异有统计学意义(P<0.05)。干预组患儿术后不良反应发生率为6.67%显著低于对照组23.33%,差异有统计学意义(P<0.05)。两组治疗前活动能力、心理健康及社交能力均低于治疗后,干预组治疗后活动能力、心理健康及社交能力均高于对照组(P<0.05)。结论:VAC结合游离植皮治疗儿童大面积皮肤缺损疗效显著,能有效降低患儿生理疼痛与心理焦虑,减少伤口感染等不良反应的发生,提高患儿生活质量,具有推广价值。  相似文献   
6.
目的对治疗前原发性骶尾部脊索瘤(PSC)CT图像分型,并分析其CT征象,为诊断和个性化治疗提供依据。方法回顾性分析101例PSC患者治疗前的CT图像,包括肿瘤的部位、范围、大小、密度、肿瘤与邻近结构的关系。按照肿瘤的部位由上及下分为Ⅰ~Ⅳ型,并根据肿瘤侵犯的范围从小到大分为a^d亚型。采用Kruskal-Wallis H检验比较PSC各亚型的占比,并对各亚型之间进行两两比较。采用R×C列联表精确概率检验比较分型和亚型肿瘤钙化的发生率。采用单因素方差分析及LSD-t检验对各分型和亚型肿瘤的大小和密度进行分析、比较。结果101例PSC中,Ⅰ~Ⅳ型的发生率分别为17.8%、30.7%、36.6%、14.9%,a^d亚型的占比分别为9.9%、25.7%、58.4%、5.9%。各亚型的占比差异具有统计学意义(P=0.012)。c亚型明显高于a亚型(P=0.039),d亚型明显低于a亚型(P=0.036),其余各型之间无明显差异。各分型肿瘤内钙化的差异无统计学意义(P=0.233);各亚型肿瘤内钙化的差异有统计学意义(P=0.003),a^d亚型肿瘤钙化的比率逐渐增加。Ⅰ型肿瘤的左右径及上下径明显大于Ⅱ~Ⅳ型(P<0.05)。a亚型与b亚型肿瘤之间前后径的差异无统计学意义(P=0.102),b^d亚型之间前后径的差异均有统计学意义(P<0.05);不同亚型肿瘤之间的左右径、上下径之间的差异均有统计学意义(P<0.05),a亚型径线最小,d亚型径线最大。结论101例PSC中,Ⅱ、Ⅲ型最多见,肿瘤较少累及第一骶骨;各亚型中,a型较少见,c亚型最多见,d亚型最少见。肿瘤的密度与分型无关,肿瘤内钙化与亚型有关。Ⅰ型肿瘤侵犯的范围较Ⅱ~Ⅳ型广泛,a^d亚型肿瘤的径线逐渐增大,CT分型有利于判断肿瘤的范围。PSC诊断延迟现象比较明显,但很少发生远处侵犯和转移。CT图像可对治疗前PSC分型,为诊断和个性化治疗提供依据。  相似文献   
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Endoscopic gastroplasty (EG) has been used in clinical practice to treat obesity. This systematic review has the objective of assessing if there is an acceptable level of scientific evidence on the safety and effectiveness of EG. A thorough search strategy was used up to October 2018, including the 2 most common techniques: endoscopic suturing and the primary obesity surgery endolumenal procedure. The quality of the studies was evaluated through the Joanna Briggs Institute Critical Appraisal tools for use in Systematic Reviews—“Checklist for Case Series”—and summarized using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach. Only 1 randomized controlled trial (moderate GRADE evidence) was found, and the remaining were case reports or small case series (very low GRADE evidence). The literature has low scientific quality. All studies, with 1 exception, are small case series with short follow-up. One of the randomized controlled trials did not meet the primary endpoint for weight loss in both groups (EG × sham) after 1-year follow-up. The case series reported from 16% to 19% total weight loss, but few had more than 6 months of follow-up. Serious adverse events ranged from 2% to 10%. Based on current literature, there is not enough quality scientific evidence regarding long-term weight loss and the procedure’s safety to recommend the use of EG in current clinical practice.  相似文献   
10.
目的 评价调整光学切削直径及Kappa角后对准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后效果的影响。方法 选取2017年1月至12月在我院行LASIK手术的高度近视患者313例(626眼),根据切削直径分成两组,试验组157例314眼,切削直径设定为6.0 mm,对照组156例312眼,切削直径设定为6.5 mm。试验组患者激光切削前修正Kappa角,对照组不做修正。患者术前进行裸眼视力、主视眼确定、验光、眼压、暗室下瞳孔直径、泪液分泌试验、裂隙灯、散瞳验光、眼底检查、pentacam测量角膜厚度、角膜地形图测量角膜前后表面及Kappa角等检查。术后1 d、1周、1个月随访,并检查裸眼视力、角膜厚度、波前像差及夜间视力、光晕、眩光等情况。比较两组患者角膜厚度变化、手术所用时间以及两组患者术后的高阶像差的差异。结果 试验组与对照组患者年龄分别为18~44(24.19±5.33)岁、18~42(25.08±4.91)岁,屈光度分别为(-7.47±1.04)D、(-7.61±1.12)D。两组年龄、屈光度比较差异均无统计学意义(均为P>0.05)。试验组与对照组患者术前Kappa角分别为,X轴:(210±40)μm、(200±30)μm,Y轴:(190±30)μm、(220±40)μm,差异无统计学意义(P=0.210)。两组手术前后的角膜厚度及术后角膜基质床的厚度差异均无统计学意义(均为P>0.05)。试验组与对照组的手术时间分别为(15.56±1.89)s和(20.83±3.03)s,差异有统计学意义(P=0.000)。试验组的总高阶像差和垂直慧差的变化均明显低于对照组(均为 P<0.01),但两组间的水平慧差差异无统计学意义(P>0.05),对照组的球差低于试验组(P<0.01)。结论 LASIK手术中科学合理地调整Kappa角可有助于提高患者术后的视觉质量。  相似文献   
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