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BackgroundReverse total shoulder arthroplasty (RSA) primarily varies between 2 implant design options: a 135 humeral stem inclination that closely resembles anatomic orientation, versus the Grammont-style 155 humeral stem inclination that further medializes and distalizes the center of rotation (COR). The purpose of this study was to compare deltoid force, glenoid strain, and simulated glenohumeral range of motion (ROM) between RSA 135 and RSA 155 designs, with a series of standardized permutations of glenosphere offset and rotator cuff pathology.MethodsTwelve fresh-frozen cadaveric shoulder specimens were studied using a shoulder simulator. Native shoulder motion profiles for reproducible abduction range of motion were established using a customized testing device. Optical 3-dimensional tracking and pressure sensors were used to accurately record glenohumeral range of motion (ROM), deltoid force, and glenoid strain for RSA 135 and RSA 155 designs. For each cohort, all combinations of glenosphere offsets and rotator cuff tendon involvement were evaluated.ResultsThere was no significant difference in the overall abduction ROM between the 155 and the 135 humeral stem implants (P = .75). Resting abduction angle and maximum abduction angle were significantly greater with a 155 + STD (standard offset) construct than with a 135 + STD construct (P < .001 and P = .01, respectively). Both stem inclinations decreased combined deltoid force requirements as compared the native shoulder with a massive cuff tear. Effective glenoid strain did not vary significantly between 135 + STD and 155 + STD constructs (P = .66).ConclusionOverall, range of motion between the 135 and the 155 humeral stem inclinations was not significantly different. The cumulative deltoid force was lower in RSA shoulders when compared to native shoulders with massive rotator cuff tears, highlighting the utility of both implant designs. The Grammont-style 155 stem coupled with a 2.5 mm inferior offset glenosphere required less deltoid force to reach maximum abduction than did the more anatomic, lateralized 135 stem coupled with a 4 mm lateral offset glenosphere.Level of EvidenceBasic Science, Biomechanics Controlled Laboratory Study  相似文献   
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目的分析江苏省启东市1972—2016年胃癌死亡流行特征。方法收集启东市1972—2016年恶性肿瘤死亡登记数据库及历年人口资料, 计算死亡率、中国人口标化率(中标率)、世界人口标化率(世标率)、35~64岁截缩率、0~74岁累积死亡率、累积死亡风险、变化百分比、死亡率年均变化百分比。结果 1972—2016年启东市胃癌死亡例数为15 863例, 占全部恶性肿瘤死亡例数的16.04%, 胃癌死亡率为31.37/10万, 中标率为12.97/10万, 世标率为21.39/10万, 35~64岁截缩死亡率为28.86/10万, 0~74岁累积死亡率为2.54%, 胃癌死亡累积风险为2.51%。男性死亡10 114例, 男性死亡率、中标率、世标率分别为40.53/10万、17.98/10万和30.13/10万;女性死亡5 749例, 女性死亡率、中标率、世标率分别为22.45/10万、8.52/10万和13.92/10万。25岁以下各年龄组的死亡率<1/10万, 死亡率随年龄的增长而升高, 50~岁组达到并超过人群的平均死亡率水平, 80~岁组达到死亡高峰。1972—2016年间胃癌死...  相似文献   
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目的 探讨全胸腔镜手术治疗婴幼儿先天性膈疝的临床效果以及安全性、可行性。方法 回顾性研究。纳入2015年4月—2021年3月南京医科大学附属儿童医院小儿心胸外科97例先天性膈疝患儿的临床资料。其中男61例、女36例,年龄2 d~3岁[(3.1 ± 7.2)个月];左侧51例,右侧46例。所有患儿均在胸腔镜下行膈疝修补术,术中观察疝内容物有无坏死、穿孔、损伤等情况,记录胸腔镜手术患儿的手术时间、术中出血量、术后胸腔引流量、引流管拔除时间、手术后住院时间。术后定期随访,观察切口感染、膈膨升、乳糜胸、气胸、肠梗阻等相关并发症发生情况,以及术后膈疝复发情况。结果 97例患儿均在全胸腔镜下顺利完成手术,无一例中转开胸手术。术中见疝囊内容物多为脾脏、胃、大网膜、结肠、小肠等,无肠穿孔坏死、肝脾出血等情况发生。手术时间75~150(90.5 ± 12.1) min,手术出血量6~15(8.3 ± 0.6) mL,术后胸腔引流量30~130(41.2 ± 7.6) mL,引流管拔除时间3~10(6.1 ± 1.3) d,手术后住院时间10~18(11.7 ± 2.1) d。住院期间因缝线脱落导致复发2例,再次行胸腔镜手术治愈;1例患儿术后第1天因左肺严重发育不良死亡。术后96例患儿均获随访,随访时间1个月~3年,平均9.2个月。随访期间无切口感染、乳糜胸、呼吸道感染、肠梗阻、肠穿孔等并发症发生,患儿生长发育良好,无一例复发。结论 全胸腔镜手术治疗婴幼儿先天性膈疝具有手术视野暴露清楚、术中出血量少、术后并发症少、住院时间短等优点,短期疗效可靠,安全可行。  相似文献   
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BackgroundResearch into oral health care for older people has shown that dental care in general decreases with increasing age and frailty and, therefore, oral health care provision may be complex. The aim of this study is to identify the oral health care dentists provide to community-dwelling older people and which barriers they experience in doing this.MethodsIn this cross-sectional study, a representative sample of dentists in the Netherlands was asked to prospectively select one older patient and describe this patient using a specially developed registration form; the patient was requested to fill out a questionnaire. The relationship between experienced barriers in providing oral health care to older patients and characteristics of the dentists and the patients was studied by means univariate and multivariate logistic regression analysis.ResultsIn total, 923 dentists were asked to participate in the study. Data were available for 39.4% dentist–patient pairs. In most cases (87.4%), oral health care was focussed on conservation of the dentition. In all, 14.0% of the dentists experienced barriers in providing oral health care for older people. Some patient factors increase the risk of experiencing barriers, eg, the more difficult behaviour of older patients and the greater disease burden.ConclusionsOral health care was mostly focussed on conservation of the dentition, and dentists especially experience barriers in oral health provision to older patients if they are already frail.  相似文献   
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Bulletin of Experimental Biology and Medicine - We studied the effect of microalgae of various systematic groups added to the ration on the biochemical parameters of blood serum and liver and...  相似文献   
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