Mixed Reality Combined with Three‐Dimensional Printing Technology in Total Hip Arthroplasty: An Updated Review with a Preliminary Case Presentation

Three‐dimensional (3D) printing technology, virtual reality, and augmented reality technology have been used to help surgeons to complete complex total hip arthroplasty, while their respective shortcomings limit their further application. With the development of technology, mixed reality (MR) technology has been applied to improve the success rate of complicated hip arthroplasty because of its unique advantages. We presented a case of a 59‐year‐old man with an intertrochanteric fracture in the left femur, who had received a prior left hip fusion. After admission to our hospital, a left total hip arthroplasty was performed on the patient using a combination of MR technology and 3D printing technology. Before surgery, 3D reconstruction of a certain bony landmark exposed in the surgical area was first performed. Then a veneer part was designed according to the bony landmark and connected to a reference registration landmark outside the body through a connecting rod. After that, the series of parts were made into a holistic reference registration instrument using 3D printing technology, and the patient's data for bone and surrounding tissue, along with digital 3D information of the reference registration instrument, were imported into the head‐mounted display (HMD). During the operation, the disinfected reference registration instrument was installed on the selected bony landmark, and then the automatic real‐time registration was realized by HMD through recognizing the registration landmark on the reference registration instrument, whereby the patient's virtual bone and other anatomical structures were quickly and accurately superimposed on the real body of the patient. To the best of our knowledge, this is the first report to use MR combined with 3D printing technology in total hip arthroplasty.     

Magnesium intake and primary liver cancer incidence and mortality in the Prostate,Lung, Colorectal and Ovarian Cancer Screening Trial

Epidemiological studies on magnesium intake and primary liver cancer (PLC) are scarce, and no prospective studies have examined the associations of magnesium intake with PLC incidence and mortality. We sought to clarify whether higher magnesium intake from diet and supplements was associated with lower risks of PLC incidence and mortality in the US population. Magnesium intake from diet and supplements was evaluated through a food frequency questionnaire in a cohort of 104,025 participants. Cox regression was employed to calculate hazard ratios for PLC incidence and competing risk regression was employed to calculate subdistribution hazard ratios for PLC mortality. Restricted cubic spline regression was employed to test nonlinearity. We documented 116 PLC cases during 1,193,513.5 person-years of follow-up and 100 PLC deaths during 1,198,021.3 person-years of follow-up. Total (diet + supplements) magnesium intake was found to be inversely associated with risks of PLC incidence (hazard ratio_{tertile 3 vs. 1}: 0.44; 95% confidence interval: 0.24, 0.80; p_trend = 0.0065) and mortality (subdistribution hazard ratio_{tertile 3 vs. 1}: 0.37; 95% confidence interval: 0.19, 0.71; p_trend = 0.0008). Similar results were obtained for dietary magnesium intake. Nonlinear inverse dose–response associations with PLC incidence and mortality were observed for both total and dietary magnesium intakes (all p_nonlinearity < 0.05). In summary, in the US population, a high magnesium intake is associated with decreased risks of PLC incidence and mortality in a nonlinear dose–response manner. These findings support that increasing the consumption of foods rich in magnesium may be beneficial in reducing PLC incidence and mortality.     

小儿腹股沟斜疝日间手术与专科住院手术的卫生经济学评价

目的对小儿日间手术模式和专科住院手术模式的卫生经济学进行评价,为小儿腹股沟斜疝手术的优选和决策提供参照依据。方法收集2016年6月至2017年7月间所有在重庆医科大学附属儿童医院治疗且符合纳入标准的单侧腹股沟斜疝患儿的临床资料,其中日间手术患儿324例(日间组),专科住院手术患儿65例(专科组)。比较两种手术模式下的患儿一般资料、治疗指标、容错情况、术后需要留院处理的并发症发生率、复发率、院内的感染等卫生效果指标;比较两种模式的HCAHPS优化星表满意度、住院时间、住院费用等卫生经济学指标。统计分析两种模式的成本-效果:治疗效果权重W、治疗效果指数(EI)、成本-效果比(CER)。结果日间外科组和专科组在性别、区域方面的差异无统计学意义,专科组年龄分布更广。日间组与专科组占用床位时间分别为(23.17±0.49)h和(112.06±19.75)h,差异具有统计学意义(P<0.01);两组的医疗费用分别为(3372±430)元和(6063±2104)元,差异具有统计学意义(P<0.01)。两组麻醉分级ASA比例的差异具有统计学意义,两组术后并发症发生率的差异无统计学意义(P>0.05)。日间组与专科组治疗EI分别为0.98和1.02,CER分别为3305和6184,日间组经济学效益较大。结论日间手术的成本-效果优于专科住院手术模式,患儿满意度和术后复发率与专科住院模式的差异无统计学意义,推荐符合日间手术指征的患儿采用该模式。     

吉林辽宁两省18年来的目标设置对突发公共卫生事件应急工作落实情况的关联研究

目的本研究立足于项目组前期研究的成果上，积极探索吉林辽宁两省目标设置水平的差异，并进一步探究受目标设置影响下的工作落实结果情况，探讨产生差异的原因。 方法以系统穷尽的方式收集吉林辽宁两省2000至2017年有关目标与工作落实情况的指标，利用Spearman相关和线性回归分析吉林辽宁两省目标设置对于突发应急工作落实情况的影响。 结果吉林辽宁两省突发应急领域的目标设置水平与工作落实情况总体均呈现上升趋势，截至2017年，吉林目标设置水平与工作落实情况分别为46%与60%，辽宁为60%与53.3%，且目标设置水平与工作落实呈正相关。 结论有公众需要为依据且定量可考的目标设置对于工作落实、推进、完善具有积极的正反馈作用，建立科学量化的突发应急目标设置评价体系是适宜可行的。     

肝癌患者行肝动脉化疗栓塞术前营养风险筛查的应用研究

目的 探讨肝癌患者行肝动脉化疗栓塞术前营养风险筛查的应用及对手术疗效、生活质量和生存预后的影响。方法 选取2013年1月至2018年12月首都医科大学附属北京世纪坛医院介入治疗科收治的行肝动脉化疗栓塞术治疗的中晚期肝癌患者180例，根据营养风险筛查2002（NRS 2002）将研究人群分为有营养风险组（NRS 2002≥3分）和无营养风险组（NRS 2002<3分），比较两组患者的临床基线特征、反映营养状况的物理和生化指标以及行肝动脉化疗栓塞术（TACE）手术疗效及并发症和生活质量评分，采用Kaplan-Meier方法对两组患者进行生存分析，比较上消化道出血、肝性脑病等临床终点事件的发生率。结果 纳入标准的180例患者中，无营养风险患者有85例，有营养风险患者有95例，营养风险发生率52.8%。两组患者的肱三头肌皮褶厚度、上臂肌围、体质指数、白蛋白之间存在统计学差异（P<0.05）；两组患者的总蛋白和前蛋白之间没有显著的统计学差异（P>0.05）。两组患者的TACE治疗肿瘤的临床有效率和术后并发症没有显著的差异（P>0.05）。无营养风险患者生活质量评分比有营养风险患者评分高（P<0.05）。有营养风险患者3年生存率为54.74%；无营养风险患者3年生存率为68.24%，存在统计学意义（HR=0.61，P=0.05， 95%CI=0.38~0.98）。肝性脑病、低蛋白血症和贫血的发生率两组之间有统计学差异（P<0.05）。上消化道出血和门脉癌栓堵塞的发生率之间没有统计学差异（P>0.05）。结论 营养风险筛查对于行TACE手术患者具有重要意义，营养风险与临床结局密切相关。     

Population Genetics Identifies Challenges in Analyzing Rare Variants

Geneticists have, for years, understood the nature of genome‐wide association studies using common genomic variants. Recently, however, focus has shifted to the analysis of rare variants. This presents potential problems for researchers, as rare variants do not always behave in the same way common variants do, sometimes rendering decades of solid intuition moot. In this paper, we present examples of the differences between common and rare variants. We show why one must be significantly more careful about the origin of rare variants, and how failing to do so can lead to highly inflated type I error. We then explain how to best avoid such concerns with careful understanding and study design. Additionally, we demonstrate that a seemingly low error rate in next‐generation sequencing can dramatically impact the false‐positive rate for rare variants. This is due to the fact that rare variants are, by definition, seen infrequently, making it hard to distinguish between errors and real variants. Compounding this problem is the fact that the proportion of errors is likely to get worse, not better, with increasing sample size. One cannot simply scale their way up in order to solve this problem. Understanding these potential pitfalls is a key step in successfully identifying true associations between rare variants and diseases.