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1.
目的:分析子野个数限值对宫颈癌固定野调强放疗(fixed-field intensity-modulated radiotherapy,ff-IMRT)计划的影响,寻求最优的子野个数限值。方法:选取10例接受ff-IMRT的宫颈癌患者,基于Monaco 5.11.03计划系统,以45 Gy/25 f处方剂量分别对同一患者设计8种ff-IMRT计划(ff-IMRT计划依据子野个数限值命名,子野个数限值分别为40、60、70、80、100、120、130、150),采用SPSS 20.0软件比较除plan100之外7个ff-IMRT计划与plan100剂量学参数、优化时间和治疗参数的差异。结果:8种ff-IMRT计划归一化后,plan40和plan60的D2%、Dmin、CI和HI均劣于plan100(P<0.05)。8种ff-IMRT计划均能较好保护危及器官(organ at risk,OAR)和正常组织。plan40小肠V45;plan40和plan60小肠D2cc,直肠、膀胱V45、D40%,两侧股骨头V40和正常组织 V35、V40均高于plan100(P<0.05)。plan40和plan60优化时间、治疗参数均优于plan100(P<0.05);plan120、plan130和plan150子野面积、子野个数(51~150 cm2和>150 cm2)和出束时间均劣于plan100(P<0.05)。结论:子野个数限值为70~100时,ff-IMRT计划能兼顾剂量学参数满足临床要求、优化时间和治疗参数最优化,建议在设计宫颈癌ff-IMRT计划时在该范围内设置子野个数限值。  相似文献   
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PurposeTo study, from a U.S. payer’s perspective, the economic consequences of drug-coated balloon (DCB) versus standard percutaneous transluminal angioplasty (PTA) use for the treatment of stenotic lesions in dysfunctional hemodialysis arteriovenous fistulae.Materials and MethodsCost differences between DCBs and PTA at year 1 and beyond were calculated via 2 methods. The first approach used the mean absolute number of trial-observed access circuit reinterventions through 12 months (0.65 ± 1.05 vs 1.05 ± 1.18 events per patient for DCBs and PTA, respectively) and projected treatment outcomes to 3 years. The second approach was based on the trial-observed access circuit primary patency rates at 12 months (53.8% vs 32.4%) and calculated the cost difference on the basis of previously published Medicare cost for patients who maintained or did not maintain primary patency. Assumptions regarding DCB device prices were tested in sensitivity analyses, and the numbers needed to treat were calculated.ResultsUsing the absolute number of access circuit reinterventions approach, the DCB strategy resulted in an estimated per-patient savings of $1,632 at 1 year and $4,263 at 3 years before considering the DCB device cost. The access circuit primary patency approach was associated with a per-patient cost savings of $2,152 at 1 year and $3,894 at 2.5 years of follow-up. At the theoretical DCB device reimbursement of $1,800, savings were $1,680 and $2,049 at 2.5 and 3 years, respectively. The one-year NNT of DCB compared to PTA was 2.48.ConclusionsEndovascular therapy for arteriovenous access stenosis with the IN.PACT AV DCB can be expected to be cost-saving if longer follow-up data confirm its clinical effectiveness.  相似文献   
3.
BackgroundAnteriorly-loaded walking is common in many occupations and may increase fall risk. Dynamic gait stability, defined by the Feasible Stability Region (FSR) theory, quantifies the kinematic relationship between the body’s center of mass (COM) and base of support (BOS). FSR-based dynamic gait stability has been used to evaluate the fall risk.Research questionHow does front load carriage affect dynamic gait stability, step length, and trunk angle among young adults during treadmill walking?MethodsIn this between-subject design study, 30 healthy young adults were evenly randomized into three load groups (0%, 10%, or 20% of body weight). Participants carried their assigned load while walking on a treadmill at a speed of 1.2 m/s. Body kinematics were collected during treadmill walking. Dynamic gait stability (the primary variable) was calculated for two gait events: touchdown and liftoff. Step length and trunk angle were measured as secondary variables. One-way analysis of variance was conducted to detect any group-related differences for all variables. Post-hoc analysis with Bonferroni correction was performed when main group differences were found.ResultsNo significant differences but medium to large effect sizes were found between groups for dynamic gait stability at touchdown (p = 0.194, η2 = 0.114) and liftoff (p = 0.122, η2 = 0.139). Trunk angle significantly increased (indicating backward lean) with the front load at touchdown (p < 0.001, η2 = 0.648) and liftoff (p < 0.001, η2 = 0.543). No significant between-group difference was found related to the step length (p = 0.344, η2 = 0.076).SignificanceCarrying a front load during walking significantly alters the trunk orientation and may change the COM-BOS kinematic relationship and, therefore, fall risk. The findings could inform the design of future studies focusing on the impact of anterior load carriage on fall risk during different locomotion.  相似文献   
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目的 探讨滋肾育胎丸加减方预防抗磷脂抗体(ACA)阳性者不良妊娠结局的效果及机制研究。方法 选取2016年2月至2019年2月我院收治的89例ACA阳性,先兆性流产或有习惯性流产(RSA)史患者,将采用西医治疗的40例作为对照组,将采用西医联合滋肾育胎丸加减方治疗的49例作为观察组,比较两组中医证候疗效、中医证候积分、ACA-IgA、ACA-IgM、ACA-IgG、凝血指标[血小板聚集功能(PAF)、活化蛋白C(PC)、抗凝血酶(AT)、纤溶酶原激活抑制物-1(PAI-1)]、Th1/Th2细胞因子[干扰素γ(IFN-γ)、白介素-2(IL-2)、白介素-4(IL-4)、白介素-10(IL-10)]、妊娠结局、安全性。结果 治疗2周后检测ACA,观察组2例未降低,对照组11例未降低,观察组未降低患者占比低于对照组(P<0.05);观察组总有效率100.00%高于对照组85.00%(P<0.05);观察组治疗4周、7周后中医证候积分低于对照组(P<0.05);观察组治疗4周、7周后ACA-IgA、ACA-IgM、ACA-IgG低于对照组(P<0.05);观察组治疗4周、7周后PAF、PAI-1低于对照组,PC、AT高于对照组(P<0.05);观察组治疗4周、7周后IFN-γ、IL-2低于对照组,IL-4、IL-10高于对照组(P<0.05);观察组活产率95.92%高于对照组80.00%(P<0.05);组间不良反应总发生率比较,差异无统计学意义(P>0.05)。结论 动态监测ACA对滋肾育胎丸加减方精准应用具有指导意义,指导滋肾育胎丸加减方通过调理脏腑、气血、经络功能,改善先兆性流产或有RSA史患者临床症状及凝血因子指标,降低ACA水平,并可改善患者免疫耐受功能,提高胎儿活产率,且安全性高。  相似文献   
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BackgroundPassive and hybrid passive ankle foot orthoses (AFOs) are often prescribed in post stroke drop foot; however, the effects of these AFOs on balance related parameters in these patients seem unclear. Accordingly, the aim of current study was to evaluate the role of the newly designed hybrid passive and Posterior Leaf Spring (PLS) AFOs on balance related parameters including: self-reported balance confidence (ABC), Timed Up and Go Test (TUG) and Berg Balance Scale (BBS) in post stroke drop foot patients.MethodsFifteen post stroke drop foot patients were recruited in current study. Then, ABC, TUG and BBS were assessed with newly designed AFO and PLS AFO.ResultsThe results of this study were shown a significant improvement in ABC, TUG and BBS scores with the newly designed AFO than PLS AFO (p < 0.05).ConclusionThis study suggested that the newly designed AFO was improved the balance related parameters than PLS AFO.  相似文献   
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《Clinical neurophysiology》2021,132(1):157-164
ObjectiveEarly EEG contains reliable information for outcome prediction of comatose patients after cardiac arrest. We introduce dynamic functional connectivity measures and estimate additional predictive values.MethodsWe performed a prospective multicenter cohort study on continuous EEG for outcome prediction of comatose patients after cardiac arrest. We calculated Link Rates (LR) and Link Durations (LD) in the α, δ, and θ band, based on similarity of instantaneous frequencies in five-minute EEG epochs, hourly, during 3 days after cardiac arrest. We studied associations of LR and LD with good (Cerebral Performance Category (CPC) 1–2) or poor outcome (CPC 3–5) with univariate analyses. With random forest classification, we established EEG-based predictive models. We used receiver operating characteristics to estimate additional values of dynamic connectivity measures for outcome prediction.ResultsOf 683 patients, 369 (54%) had poor outcome. Patients with poor outcome had significantly lower LR and longer LD, with largest differences 12 h after cardiac arrest (LRθ 1.87 vs. 1.95 Hz and LDα 91 vs. 82 ms). Adding these measures to a model with classical EEG features increased sensitivity for reliable prediction of poor outcome from 34% to 38% at 12 h after cardiac arrest.ConclusionPoor outcome is associated with lower dynamics of connectivity after cardiac arrest.SignificanceDynamic functional connectivity analysis may improve EEG based outcome prediction.  相似文献   
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Zygomatic implants (ZIs) are used for the oral rehabilitation of patients with maxillectomy defects as an alternative to extensive bone grafting surgeries. New technologies such as computer-assisted navigation systems can improve the accuracy and safety of ZI placement. The intraoral anchorage of fiducial markers necessary for navigation registration is not possible in the case of a severe maxillary defect and lack of residual bone. This technical note presents a novel extraoral registration method for a dynamic navigation system guiding ZI placement in patients with maxillectomy defects. Titanium microscrews were inserted in the mastoid process, supraorbital ridge, and posterior zygomatic arch as registration markers. The mean fiducial registration error (FRE) was 0.53 ± 0.20 and the deviations between the planned and placed ZIs were 1.56 ± 0.54 mm (entry point), 1.87 ± 0.63 mm (exit point), and 2.52 ± 0.84° (angulation). The study results indicate that the placement of fiducial markers at extraoral sites can be used as a registration technique to overcome anatomical limitations in patients after maxillectomy, with a clinically acceptable registration accuracy.  相似文献   
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