纸本与数字的交互：手机阅读的最佳效果

随着全球3G商用的推进和拥有大容量存储能力的智能终端的日益普及,手机正逐步演变成为一个新型的数字阅读终端。利用手机进行电子阅读的全新模式,正以前所未有的普及速度冲击着人们的阅读习惯。而这趋势也逐渐为"阅读"进行重新的定义。对于每一个读者而言,在这样一个信息化的时代里,手机阅读和纸本阅读的交互使用、取长补短,才是获得最佳阅读效果的最有效方式。     

试论岳甫嘉医案中不育的诊治思维

岳甫嘉诊病重视脉症合参,尤以诊脉见长;处方多用中和之剂,收固真阴,反对过用热药,耗散精血。诊治思维贯穿其著作《妙一斋医学正印种子编》上卷所载验案。此卷专门论述男性不育的诊治,虽仅载验案八则,但八者皆奇,诊治结合,涵盖多法,可归纳为“先清热毒,再施温补”“药用滑涩,当辨标本”“先治脾,后治肾”“脾肾同治”“先祛痰火,再滋肾阴”及“交通心肾”6类,诸法之中的诊治思维,蕴含奥妙,颇具特色,特作探析。     

Custom 3-Dimensional Printed Ultrasound-Compatible Vascular Access Models: Training Medical Students for Vascular Access

PurposeTo generate 3-dimensional (3D) printed ultrasound (US)-compatible vascular models (3DPVAM) and test them for noninferiority in training medical students in femoral artery access.Materials and MethodsA 3DPVAM of normal femoral artery (FA) anatomy was developed from an anonymized computerized tomography (CT) examination. Students were randomized to a 3DPVAM or a commercial model (CM) simulation experience (SE) for US-guided FA access. Students completed a pre-SE questionnaire ranking their self-confidence in accessing the artery on a 5-point Likert scale. A standardized SE was administered by interventional radiology faculty or trainees. Students completed a post-SE questionnaire ranking comfort with FA access on a Likert scale. Student questionnaire results from the 3DPVAM group were compared with those from the CM group by using chi-square, Wilcoxon signed-rank, and noninferiority analyses.ResultsTwenty-six and twenty-three students were randomized to 3DPVAM and commercial model training, respectively. A total of 76.9% of 3DPVAM trainees and 82.6% of CM trainees did not feel confident performing FA access prior to the SE. In both groups, training increased student confidence by 2 Likert points (3DPVAM: P < 0.001; CM P < 0.001). The confidence increase in 3DPVAM trainees was noninferior to that in CM trainees (P < 0.001).ConclusionsGeneration of a custom-made 3DPVAM is feasible, producing comparable subjective training outcomes to those of CM. Custom-made 3D-printed training models, including incorporation of more complex anatomical configurations, could be used to instruct medical students in procedural skills.     

ACR Neck Imaging Reporting and Data Systems (NI-RADS): A White Paper of the ACR NI-RADS Committee

Imaging surveillance after treatment for head and neck cancer is challenging because of complicated resection and reconstruction surgery, in addition to posttreatment changes from radiation and chemotherapy. The posttreatment neck is often a source of anxiety for diagnostic radiologists, leading to suboptimal reporting and no standardized guidance for next management steps. Nevertheless, imaging is critical for detecting submucosal recurrences in a timely manner, so that patients remain candidates for salvage surgery. In 2016, the ACR convened the Neck Imaging Reporting and Data Systems (NI-RADS) Committee with the goals to (1) provide recommendations for surveillance imaging; (2) produce a lexicon to distinguish between benign posttreatment change and residual or recurrent tumor in the posttreatment neck; and (3) propose a NI-RADS template for reporting on the basis of this lexicon with defined levels of suspicion and management recommendations. In this article, the authors present the ACR NI-RADS Committee’s recommendations, which provide guidance regarding the management of patients after treatment for head and neck cancer.     

Characterization of Printed Circuit Boards for Metal and Energy Recovery after Milling and Mechanical Separation

The proper disposal of electrical and electronic waste is currently a concern of researchers and environmental managers not only because of the large volume of such waste generated, but also because of the heavy metals and toxic substances it contains. This study analyzed printed circuit boards (PCBs) from discarded computers to determine their metal content and characterized them as solid waste and fuel. The analysis showed that PCBs consist of approximately 26% metal, made up mainly of copper, lead, aluminum, iron and tin, as well as other heavy metals such as cadmium and nickel. Comparison with the results of other studies indicated that the concentration of precious metals (gold and silver) has declined over time. Analysis of the leachate revealed high concentrations of cadmium and lead, giving the residue the characteristics of hazardous waste. After milling the PCBs, we found that larger amounts of metal were concentrated in smaller fractions, while the lightest fraction, obtained by density separation, had a gross calorific value of approximately 11 MJ/kg, although with a high ash content. Milling followed by density separation proved potentially useful for recovery of metals and energy-rich fractions.     

基于乌斯坦因模式的心肺复苏研究报告

目的 心肺复苏Utstein评价模式已被许多国家广泛用于心肺复苏评价研究.本文以心肺复苏结果Utstein评价模式设计心肺复苏注册登记表,以评价中国海南海南省人民医院心搏骤停患者流行病学特征、心肺复苏效果与影响因素.方法 应用心肺复苏Utstein模式注册登记表,对海南省人民医院急诊科511例心肺复苏患者进行前瞻性观察研究,评价本组患者心搏骤停流行病学特征及心肺复苏结果.结果 注册登记的511例心肺复苏患者纳入研究.本研究患者以40 ～ 70岁等年龄段心搏骤停发生率较高.既往史中,心血管系统疾病(190例,37.2％)、脑血管疾病(48例,9.4％)及呼吸系统疾病(39例,7.6％)等慢性疾病较为常见.173例(33.9％)为心源性心搏骤停,其中109例(21.3％)为急性心肌梗死.80例(15.7％)患者首次监测心律为心室纤颤.院内心搏骤停患者自主循环恢复率及成活出院率分别为47.0％和13.5％,院外心搏骤停患者为16.7％和4.7％.结论 本研究表明心血管系统疾病、脑血管疾病及呼吸系统疾病为最常见慢性疾病.急性心肌梗死、中风及创伤为最常见心搏骤停病因.院内心搏骤停组自主循环恢复率及成活出院率均高于院外心搏骤停组,两组差异具有统计学意义.     

Bone regeneration by means of a three‐dimensional printed scaffold in a rat cranial defect

Recently, computer‐designed three‐dimensional (3D) printing techniques have emerged as an active research area with almost unlimited possibilities. In this study, we used a computer‐designed 3D scaffold to drive new bone formation in a bone defect. Poly‐L‐lactide (PLLA) and bioactive β‐tricalcium phosphate (TCP) were simply mixed to prepare ink. PLLA + TCP showed good printability from the micronozzle and solidification within few seconds, indicating that it was indeed printable ink for layer‐by‐layer printing. In the images, TCP on the surface of (and/or inside) PLLA in the printed PLLA + TCP scaffold looked dispersed. MG‐63 cells (human osteoblastoma) adhered to and proliferated well on the printed PLLA + TCP scaffold. To assess new bone formation in vivo, the printed PLLA + TCP scaffold was implanted into a full‐thickness cranial bone defect in rats. The new bone formation was monitored by microcomputed tomography and histological analysis of the in vivo PLLA + TCP scaffold with or without MG‐63 cells. The bone defect was gradually spontaneously replaced with new bone tissues when we used both bioactive TCP and MG‐63 cells in the PLLA scaffold. Bone formation driven by the PLLA + TCP30 scaffold with MG‐63 cells was significantly greater than that in other experimental groups. Furthermore, the PLLA + TCP scaffold gradually degraded and matched well the extent of the gradual new bone formation on microcomputed tomography. In conclusion, the printed PLLA + TCP scaffold effectively supports new bone formation in a cranial bone defect.     

两种3D打印导板在托槽间接粘接中的准确性比较

目的:评估两种3D打印导板在辅助托槽间接粘接时准确性的差异。方法:利用离体牙按照牙弓形态排牙,标记测量点建立实验模型备用。通过数字化扫描仪获取数字化模型,利用计算机软件设计3D打印整段式和单牙位导板。通过制作的间接粘接导板将托槽转移定位到实验模型,测量标记点与托槽特定位点间距离,对转移前后距离的变化进行统计学分析。结果:通过配对t检验分析,整段式和单牙式两种3D打印导板在托槽转移前后位置变化差值分别为（0.21±0.05） mm、（0.22±0.05） mm,两者无统计学差异（P>0.05）。结论:在上述实验条件下,两种3D打印导板在辅助托槽间接粘接过程中准确性无明显差异。     

Optimisation of a guided endodontics protocol for removal of fibre‐reinforced posts

This paper demonstrates the usefulness of endodontic guides for the removal of fibre posts. A 36‐year‐old man consulted for retreatment of a maxillary first molar presenting a periapical pathology. This tooth revealed a composite reconstruction together with a glass‐fibre post in the palatal root canal. To assist removal, use of an endodontic 3D‐printed guide was indicated. A cone beam computed tomography examination and an optical impression were made to produce a tooth‐supported guide by means of implant planning software (Blue Sky Plan, Blue Sky Bio^®). The software enabled definition of a drilling pathway, which was transferred clinically using a resin template together with a sleeve and a 0.75‐mm drill. The drill was guided as far as the gutta‐percha situated in the apical third, limiting any risk of impairment or perforation.