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31.
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   
32.
目的探讨阻塞性睡眠呼吸暂停低通气综合征(OSAHS)CYP3A4基因的多态性,了解其对芬太尼类药物的敏感性及不同基因型的人群分布特征,指导临床个体化用药。方法对50例OSAHS患者进行CYP3A4基因的多态性检测,采静脉血,通过DNA抽提-PCR扩增-焦磷酸测序方法检测CYP3A4基因。结果野生纯合型型34例(68%),突变杂合型15例(30%),突变纯合型型1例(2%)。结论OSAHS患者中约2%为AA型,该型对芬太尼类药物极其敏感,术后有易发生窒息的风险,应高度警惕芬太尼类药物呼吸抑制的潜在风险。  相似文献   
33.
Responsive feeding (RF) has been recognized as necessary to prevent all forms of malnutrition including stunting and childhood obesity. Specific RF guidelines have been developed, but it is unclear how RF behaviours can be monitored systematically. Therefore, developing valid and reliable abbreviated and pragmatic RF scales is an important global priority. This is challenging, as RF is a construct with multiple dimensions including recognizing and responding to hunger and satiety cues, providing a nurturing environment during feeding episodes, and understanding how feeding needs evolve as a function of the developmental stage of the young child. Further, RF is embedded within the responsive parenting framework that in addition to RF includes sleep, soothing and play routines and the interconnections between them. A recent pioneer study conducted in a rural area of Cambodia validated an 8‐item RF scale through direct feeding observations of 6‐ to 23‐month‐old infants at home, as part of two cross‐sectional surveys conducted before and after a complementary feeding intervention. It is important for similar research to be conducted elsewhere to find out if it is possible or not to develop a core RF scale that is valid and reliable and that has adequate specificity and sensitivity for application in community studies and population surveys globally. As highlighted in this article, different definitions of RF have been used in the field; thus, it is important to reach consensus on a single definition to help move this research area forward.  相似文献   
34.
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型相似文献   
35.

Purpose

Chest wall pain is an uncommon but bothersome late complication following lung stereotactic body radiation therapy. Despite numerous studies investigating predictors of chest wall pain, no clear consensus has been established for a chest wall constraint. The aim of our study was to investigate factors related to chest wall pain in a homogeneous group of patients treated at our institution.

Patients and methods

All 122 patients were treated with the same stereotactic body radiation therapy regimen of 48 Gy in three fractions, seen for at least 6 months of follow-up, and planned with heterogeneity correction. Chest wall pain was scored according to the Common Terminology Criteria for Adverse Events classification v3.0. Patient (age, sex, diabetes, osteoporosis), tumour (planning target volume, volume of the overlapping region between planning target volume and chest wall) and chest wall dosimetric parameters (volumes receiving at least 30, 40, and 50 Gy, the minimal doses received by the highest irradiated 1, 2, and 5 cm3, and maximum dose) were collected. The correlation between chest wall pain (grade 2 or higher) and the different parameters was evaluated using univariate and multivariate logistic regression.

Results

Median follow-up was 18 months (range: 6–56 months). Twelve patients out of 122 developed chest wall pain of any grade (seven with grade 1, three with grade 2 and two with grade 3 pain). In univariate analysis, only the volume receiving 30 Gy or more (P = 0.034) and the volume of the overlapping region between the planning target volume and chest wall (P = 0.038) significantly predicted chest wall pain, but these variables were later proved non-significant in multivariate regression.

Conclusion

Our analysis could not find any correlation between the studied parameters and chest wall pain. Considering our present study and the wide range of differing results from the literature, a reasonable conclusion is that a constraint for chest wall pain is yet to be defined.  相似文献   
36.
37.
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   
38.
《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   
39.
目的探讨基因间长链非编码RNA 152(LINC00152)靶向调控微小RNA-103a-3p(miR-103a-3p)表达及对非小细胞肺癌(NSCLC)细胞增殖和侵袭迁移的影响。方法采用实时定量PCR(QPCR)检测正常肺上皮细胞BEAS-2B及NSCLC细胞(ANIP-973、NCI-H157、A549和NCI-H1975)的LINC00152水平。选取LINC00152水平最高的细胞分别转染LINC00152特异性小干扰RNA(si-LINC00152组)或无关序列(si-NC组),另设未转染细胞为对照组。QPCR检测LINC00152水平,活细胞计数CCK-8法、Transwell小室和划痕实验测定细胞增殖、侵袭和迁移能力,Western blotting检测基质金属蛋白酶(MMP)-2、MMP-9和第10号染色体缺失的磷酸酶及张力蛋白同源基因(PTEN)的水平;荧光素酶报告实验验证LINC00152靶向结合miR-103a-3p的能力。结果NSCLC细胞的LINC00152水平均高于BEAS-2B细胞(P<0.05),尤其是NCI-H1975细胞的最高。si-LINC00152组的LINC00152水平为0.352±0.087,低于对照组的1.058±0.219和si-NC组的1.126±0.139(P<0.05)。与si-NC组和对照组相比,si-LINC00152组NCI-H1975细胞转染48、72 h的增殖活力下降(P<0.05);si-LINC00152组的划痕愈合率和穿膜细胞数分别为(27.386±2.428)%和(78.840±5.031)个,低于si-NC组的(77.675±4.803)%和(179.208±13.264)个及对照组的(76.371±5.385)%和(174.003±15.678)个(P<0.05);与si-NC组和对照组相比,si-LINC00152组的MMP-2和MMP-9水平均降低,而PTEN水平升高(P<0.05)。对照组和si-NC组上述指标的差异无统计学意义(P>0.05)。双荧光素酶报告分析证实,miR-103a-3p模拟物降低了野生型LINC00152的荧光素酶活性(P<0.05),但对突变型无影响(P>0.05)。结论LINC00152在NSCLC细胞中高表达并发挥促癌作用,与NSCLC的迁移侵袭密切相关,LINC00152与miR-103a-3p间的相互作用在NSCLC靶向治疗中有一定潜能。  相似文献   
40.
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