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11.
《Vaccine》2020,38(3):570-577
IntroductionPediatric pneumococcal pneumonia complicated by parapneumonic pleural effusion/empyema (PPE/PE) remains a major concern despite general immunization with pneumococcal conjugate vaccines (PCVs).MethodsIn a nationwide pediatric hospital surveillance study in Germany we identified 584 children <18 years of age with bacteriologically confirmed PPE/PE from October 2010 to June 2018. Streptococcus pneumoniae was identified by culture and/or PCR of blood samples and/or pleural fluid and serotyped.ResultsS. pneumoniae was identified in 256 of 584 (43.8%) children by culture (n = 122) and/or PCR (n = 207). The following pneumococcal serotypes were detected in 114 children: serotype 3 (42.1%), 1 (25.4%), 7F (12.3%), 19A (7.9%), other PCV13 serotypes (4.4%) and non-PCV13 serotypes (7.9%). Between October 2010 and June 2014 serotype 1 (38.1%) and serotype 3 (25.4%) were most prevalent, whereas between July 2014 and June 2018 serotype 3 (62.7%) and non-PCV13 serotypes (15.7%) were dominant. Compared to children with other pneumococcal serotypes, children with serotype 3 associated PPE/PE were younger (median 3.2 years [IQR 2.1–4.3 years] vs. median 5.6 years [IQR 3.8–8.2 years]; p < 0.001) and more frequently admitted to intensive care (43 [89.6%] vs. 48 [73.8%]; p = 0.04). Seventy-six of 114 (66.7%) children with pneumococcal PPE/PE had been vaccinated with pneumococcal vaccines. Thirty-nine of 76 (51.3%) had received a vaccine covering the serotype detected. Thirty of these 39 breakthrough cases were age-appropriately vaccinated with PCV13 and considered vaccine failures, including 26 children with serotype 3, three children with serotype 19A and one child with serotype 1.ConclusionFollowing the introduction of PCV13 in general childhood vaccination we observed a strong emergence of serotype 3 associated PPE/PE in the German pediatric population, including a considerable number of younger children with serotype 3 vaccine breakthrough cases and failures. Future PCVs should not only cover newly emerging serotypes, but also include a more effective component against serotype 3. 相似文献
12.
【摘要】 报道临床症状不典型的家族性黑棘皮病1家系。先证者女,4岁,自1周岁时,颈部、腹部出现黑色斑片,近年来逐渐扩大至唇周、躯干前部。腹部皮肤全反式共聚焦显微镜检查可见乳头环下延扭曲及沟壑结构,乳头环内可见中高折光颗粒结构。先证者父亲及祖母既往有类似病史,但随着年龄增长色素沉着自发性消退,仅有局部皮纹增粗。采集先证者及父母、祖母外周血,对先证者外周血DNA行Panel靶向测序,结果显示,先证者存在FGFR3基因14号外显子c.1949A>C(p.Lys650Thr)错义突变,Sanger测序验证证实先证者及其父亲和祖母均存在此突变。诊断:家族性黑棘皮病。 相似文献
13.
《Diagnostic and interventional imaging》2020,101(9):555-564
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%. 相似文献
14.
文题释义:股骨头坏死中日友好医院分型的有限元分析:根据李子荣等提出的中日友好医院分型,建立股骨头坏死三维模型,分为 M型(内侧型)、C型(中央型)和 L型(外侧型),其中 L型包括L1型(次外侧型)、L2型(极外侧型)和 L3型(全头型)。通过对建立的模型进行有限元分析,为该分型的保髋治疗提供了一定力学依据,显示外侧柱的存留是精准预防塌陷的重要因素,为进一步实现个体化治疗提供力学基础。
腓骨支撑坏死股骨头保髋手术:是对于早中期股骨头坏死需要保留股骨头患者进行的一种手术方式。首先需对股骨头进行髓芯减压,清除一定坏死骨,空腔填塞松质骨(髂骨为主),打压结实后植入腓骨(异体或自体)支撑,给坏死区的提供力学支撑及生物学修复,预防股骨头进一步坏死及塌陷。
背景:研究报道股骨头坏死的保髋疗效与外侧柱存留密切相关,中日友好医院分型是根据三柱结构确立的,对股骨头塌陷的预测准确性高。
目的:建立股骨头坏死中日友好医院分型各分型仿真的三维有限元模型,通过有限元分析各分型腓骨植入的力学变化,探讨外侧柱存留对保髋疗效的意义,为该分型的塌陷精准预测提供基础。
方法:建立正常股骨头、中日友好医院分型(M型、C型、L1型、L2型、L3型)股骨头坏死及其腓骨植入3组11种三维有限元模型,运用ANSYS软件进行有限元分析计算,观察各组模型的最大应力值、最大位移值及股骨头内部载荷传递模式。
结果与结论:①坏死组位移最大,应变最大,且因坏死分型不同而位移不同,位移变化如下:M型3型;腓骨植入组位移恢复均低于正常组,且因坏死分型不同而位移恢复不同,位移变化如下:M型3型,修复后的坏死股骨头的位移下降幅度从外侧柱到内侧柱逐级变小,均低于正常股骨头的最大位移。②坏死后的股骨头载荷区表面应力云图呈现的峰值均高于正常组,坏死M型基本接近正常,坏死C型峰值高出正常74.5%,坏死L型峰值均高出正常100%以上;坏死M型术后的峰值不但比术前下降14.2%,也低于正常水平;坏死C型术后的峰值比术前下降5.3%,但高于正常水平;坏死L型术后的峰值比术前下降,但均明显高于正常水平。③正常股骨头内部的载荷传递是连续的,传导路径从股骨头外侧柱到股骨矩。坏死组中M、C型的股骨头内部载荷传递是连续的,M型的传导基本与正常一致,C型的传导到股骨矩的应力减少;L1、L2、L3型的股骨头内部的载荷传递出现中断,应力出现断崖式的变化,无法传导到股骨矩,导致股骨头载荷区应力集中。腓骨植入组中的股骨头内部重建了一定有效的载荷传递模式,所有分型的传导都出现股骨矩处的应力集中,部分载荷通过腓骨传递到股骨矩上,正常载荷传递模式得到部分恢复。④提示中日友好医院分型腓骨植入能在一定程度上预防坏死股骨头的塌陷,坏死区位置及大小至关重要,坏死越靠近外侧柱越容易塌陷,修复越困难,外侧柱的存留是精准预测股骨头塌陷的重要考虑因素。
ORCID: 0000-0001-7981-950X(凌观汉)
中国组织工程研究杂志出版内容重点:人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程 相似文献
15.
《International journal of oral and maxillofacial surgery》2020,49(11):1445-1448
The advent of customized three-dimensional (3D) printing allows the affordable manufacturing of sophisticated medical devices, thereby providing swift and simple solutions to specific needs in modern healthcare. Meanwhile, certain devices such as industrial mandibular external fixators (EFs) have become less and less available from medical device companies because of decreased indications. What is more, their handling is often complex. The authors report, step by step, the original design and uneventful clinical use of a 3D-printed, customized mandibular EF. This device was designed together with a positioning and drilling guide for the fixation of a septic mandibular pseudarthrosis. It provided an adequate and satisfactory balance between lightness and rigidity. A simple, accurate and safe placement of the EF was achieved thanks to the skin-supported positioner and drilling guide, thereby making the procedure minimally invasive and time-efficient. To our knowledge, this is the first reported clinical use of a 3D-printed, customized mandibular EF to date. Because such 3D technology is becoming increasingly available to a large number of surgeons, the authors believe that the present innovation could become an alternative to reusable standard EFs. 相似文献
16.
《Injury》2022,53(2):676-682
Aim3D-printed implants could improve the capture of fracture fragments for improved stability of tibial plateau fracture fixation. The aim of this study was to compare the biomechanical strength of fixation constructs using standard and customised 3D-printed proximal tibial locking plates for fixation of tibial plateau fractures.MethodsThis is a biomechanical study utilising six pairs of cadaveric tibiae. Fractures were created in an identical fashion using an osteotome and mallet, and fixed using either a standard, commercially-available proximal tibia locking plate or a customised 3D-printed plate. Design and production of the customised plates followed a “3D printing at point-of-care” model. Customised stainless steel 316 L plates were produced within a local additive manufacturing laboratory based upon pre-operative CT scans. Determination of implant choice within each cadaver pair was performed via simple randomisation. Following fracture fixation, the tibiae were skeletalised and biomechanically tested using a customised loading jig and a size-matched femoral knee prosthesis. The constructs were loaded cyclically from 100 N to approximately three times the cadaveric body-weight at 5 Hz for 10 000 cycles. Every 1000 cycles, the test was paused and the tibia was physically checked for failure. If failure had not occurred by the end of the testing cycle, the construct was loaded to failure and the load at which the construct failed was noted.ResultsFixation constructs using the 3D-printed plates performed comparably to those using the standard plates. There was no significant difference in the degree of fracture fragment displacement in both constructs. Overall longitudinal construct stiffness and load to failure was higher in the 3D-plates group but this did not reach statistical significance.ConclusionProduction of customised plates for proximal tibia fractures at point-of-care is feasible, however fixation constructs with these plates did not provide any biomechanical advantage over standard plates in terms of axial loading stiffness. 相似文献
17.
18.
Rosario Gulias-Cañizo Anell Lagunes-Guillén Arturo González-Robles Erika Sánchez-Guzmán Federico Castro-Muñozledo 《Burns : journal of the International Society for Burn Injuries》2019,45(2):398-412
19.
20.
目的3a2;讨对先天性33;u32;腔型小33;畸形؊3;者行全扩张法全33;再造术后,利用残33;皮ݎ3;e39;善再造33;颅33;沟的效果3002;方法回顾分析 2012 年 1 月—2017 年 1 月e36;治的 150 例先天性33;u32;腔型小33;畸形؊3;者3002;其中u37; 92 例,֗3; 58 例;年龄 6.5~35.0 岁,ק3;均 11.1 岁3002;采用一期扩张器埋置3001;二期全扩张法全33;再造术后3d1;3b0;上部颅33;沟浅f3e;;于 6~12 个月后行三期再造33;修整3002;将残33;垂通过“Z”字e39;型转移以再造33;垂3002;在残33;上部作蒂在轮屏切迹的残33;上部皮ݎ3;,弧形切开松࢞3;并加深上部颅33;沟,将上部残33;皮ݎ3;向颅33;沟创面旋转3a8;进缝合以覆盖创面;将带皮下组织蒂的残33;软骨组织ݎ3;3d2;入支架底部形成的腔隙内,并缝合固定,以增加支架的高度;33;u32;腔33a;其余残33;皮ݎ3;用以覆盖33;u32;腔创面3002;߭3;果术后拆线时 1 例؊3;Q3f;皮ݎ3;远端出3b0;直径约 0.5 cm 的表皮l34;疱,经362;36f; 2 周后愈合;其余؊3;者皮ݎ3;成m3b;良好3002;؊3;者均3b7;随访,随访时间 6~12 个月,ק3;均 9.6 个月3002;再造33;上部颅33;沟均明f3e;加深,再造33;支架高度不同程度增加,3cc;33;对称性ӷ3;,33;u32;腔无明f3e;31b;缩3d8;小,再造33;外观满意3002;再造33;上部表面毛3d1;明f3e;减少,33;周3d1;际线上移3002;߭3;论采用33;u32;腔型小33;畸形的残33;皮ݎ3;3ca;残33;软骨ݎ3;转移,不仅3ef;加深颅33;沟,而且3ef;增加上部支架的高度,术后颅33;沟3d8;形ࣸ3;轻,再造33;与ڶ3;^38;33;3;的对称性更ӷ3;3002; 相似文献