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11.
目的:探讨3D打印导航模板辅助椎弓根螺钉在脊柱侧弯矫形术中的置钉效果.方法:回顾性分析2018年1月至2020年6月间采用椎弓根螺钉置钉法治疗的39例脊柱侧弯患者的病例资料,其中采用3D打印导航模板辅助置钉(3D组)18例,常规徒手置钉方法置钉(徒手组)21例.记录并比较2组的置钉时间、置钉出血量、置钉透视次数、置钉等...  相似文献   
12.
目的:评估国家药品监督管理局(NMPA)官网中非处方药说明书范本关于妊娠期和哺乳期女性用药信息标示的完整性和准确性。方法:收集截止到2018年11月11日NMPA官网中,非处方药化学药品说明书范本和非处方药中成药说明书范本,对范本的【禁忌】和【注意事项】中关于妊娠期和哺乳期女性用药信息标示情况进行统计分析。结果:我国非处方药说明书范本对妊娠期和哺乳期女性用药信息的标示情况仍存在较大空缺。非处方药化学药品说明书范本的用药信息标示率低于中成药(P<0.05),但其对妊娠期和哺乳期女性有指导意义的用药信息标示率明显高于中成药(P<0.01);对妊娠期女性有指导意义的用药信息标示率明显高于哺乳期女性(P<0.01)。结论:保障妊娠期和哺乳期女性用药的安全和有效,需要不断完善和规范说明书范本的用药信息,建立妊娠期和哺乳期女性用药信息数据库等措施。  相似文献   
13.
目的: 利用数字化印模技术建立种植导板精度的非放射学评价方法,评估体外全程导航手术的种植精度。方法: 利用3Shape Implant Studio软件,在15个相同的缺牙树脂模型中设计2颗平行种植体位点,生成并打印相应的数字化种植导板并在导板全程导航下植入2颗种植体。术后分别以传统放射学方法及数字化印模杆、口内扫描仪、通用逆向工程软件构成的数字化评价方法检测每组种植体偏移情况,采用SPSS 23.0软件包进行数据分析。结果: 以数字化评价方法得到的全程种植导板平均精度为肩部偏差0.447 mm,根尖部偏差0.557 mm, 角度平均偏差1.134°。与传统放射学评价方法相比,2种评价方法在距离偏差方面无统计学差异(P>0.05);在角度偏差分析中,数字化评价方法更优(P<0.05)。种植体偏差多集中在冠根方向,且根尖偏移较颈部偏移更明显。结论: 与放射学评价手段相比,数字化非放射学评价方法可准确评价种植精度,有效减少患者辐射暴露。  相似文献   
14.
One fundamental challenge in diffusion magnetic resonance imaging (dMRI) harmonization is to disentangle the contributions of scanner-related effects from the variable brain anatomy for the observed imaging signals. Conventional harmonization methods rely on establishing an atlas space to resolve anatomical variability and generate a unified inter-site mapping function. However, this approach is limited in accounting for the misalignment of neuroanatomy that still widely persists even after registration, especially in regions close to cortical boundaries. To overcome this challenge, we propose a personalized framework in this paper to more effectively address the confounding from the misalignment of neuroanatomy in dMRI harmonization. Instead of using a common template representing site-effects for all subjects, the main novelty of our method is the adaptive computation of personalized templates for both source and target scanning sites to estimate the inter-site mapping function. We integrate our method with the rotation invariant spherical harmonics (RISH) features to achieve the harmonization of dMRI signals between sites. In our experiments, the proposed approach is applied to harmonize the dMRI data acquired from two scanning platforms: Siemens Prisma and GE MR750 from the Adolescent Brain Cognitive Development dataset and compared with a state-of-the-art method based on RISH features. Our results indicate that the proposed harmonization framework achieves superior performance not only in reducing inter-site variations due to scanner differences but also in preserving sex-related biological variability in original cohorts. Moreover, we assess the impact of harmonization on the estimation of fiber orientation distributions and show the robustness of the personalized harmonization procedure in preserving the fiber orientation of original dMRI signals.  相似文献   
15.
近年来计算机断层扫描技术、种植三维修复设计软件、数字化种植外科手术导板加工技术在口腔种植学领域的应用得到了很快发展,计算机辅助设计种植手术导板在临床中已有较多临床病例报道。本文就种植手术导板的数字化加工的技术发展、数字化手术导板的分类、临床实际操作流程、适应证选择进行分析总结,为临床实际应用提供参考依据。  相似文献   
16.
In iris recognition, feature extraction can be influenced by factors such as illumination and contrast, and thus the features extracted may be unreliable, which can cause a high rate of false results in iris pattern recognition. In order to obtain stable features, an algorithm was proposed in this paper to extract key features of a pattern from multiple images. The proposed algorithm built an iris feature template by extracting key features and performed iris identity enrolment. Simulation results showed that the selected key features have high recognition accuracy on the CASIA Iris Set, where both contrast and illumination variance exist.  相似文献   
17.
Some advanced methods for DNA profile interpretation require a probability for the event of dropout. Methods have been suggested based on logistic regression. Two of these respectively use a proxy for template that is constant across loci and one that is modelled using an exponential curve. Both of these methods allow different modelling constants from each locus. A variant of the model using an exponential curve is discussed. This variant constrains the constants to be the same for every locus. We test these two methods and the variant by developing the constants (training) on one set of data and testing them on another. This mimics the likely use in casework. We find that the new variant appears to be the most useful in that it performs better than the other two options when trained on one data set and used on another. The hypothesised reason for this is that locus to locus variation in amplification efficiency varies with time, multimix batch, or from sample to sample.  相似文献   
18.
PurposeThe aim of this study was to assess the impact of a structured reporting template on adherence to the Prostate Imaging Reporting and Data System (PI-RADS) version 2 lexicon and on the diagnostic performance of prostate MRI to detect clinically significant prostate cancer (CS-PCa).MethodsAn imaging database was searched for consecutive patients who underwent prostate MRI followed by MRI-ultrasound fusion biopsy from October 2015 through October 2017. The initial MRI reporting template used included only subheadings. In July 2016, the template was changed to a standardized PI-RADS-compliant structured template incorporating dropdown menus. Lesion, patient characteristics, pathology, and adherence to the PI-RADS lexicon were extracted from MRI reports and patient charts. Diagnostic performance of prostate MRI to detect CS-PCa using combined ultrasound-MRI fusion and systematic biopsy as a reference standard was assessed.ResultsThree hundred twenty-four lesions in 202 patients (average age, 67 years; average prostate-specific antigen level, 5.9 ng/mL) were analyzed, including 217 MRI peripheral zone (PZ) lesions, 84 MRI non-PZ lesions, and 23 additional PZ lesions found on systematic biopsy but missed on MRI. Thirty-three percent (106 of 324) were CS-PCa. Adherence to the PI-RADS lexicon improved from 32.9% (50 of 152) to 88.4% (152 of 172) (P < .0001) after introduction of the structured template. The sensitivity of prostate MRI for CS-PCa in the PZ increased from 53% to 70% (P = .011). There was no significant change in specificity (60% versus 55%, P = .458).ConclusionsA structured template with dropdown menus incorporating the PI-RADS lexicon and classification rules improves adherence to PI-RADS and may increase the diagnostic performance of prostate MRI for CS-PCa.  相似文献   
19.
在前期提出超分子化学对中药四性理论特殊影响的基础上,进一步分析中药升降浮沉的历史沿革、研究概况,并运用超分子"印迹模板"理论对中药"升降浮沉"理论进行解析,提出对中药"升降浮沉"的评价方法。人体与中药均是印迹模板印迹作用的聚集体,在印迹模板作用规律下,不同类型的中药成分与人体的靶点通过"锁-钥"关系以非共价键结合,中药客体超分子通过键的作用可纠正人体主体超分子在自识别、自组织、自组装、自复制过程时发生的寒热、气机失调。人体具备抵抗外界病邪侵袭的能力,有赖于其气机"升降出入"的正常;中药具有"升降浮沉"的性能并能祛除病疾,有赖于其能调整人体气机紊乱,或顺应气机、祛邪外出以增强机体免疫的能力。基于此,在分析中药"升降浮沉"药理作用的基础上,探究其物质基础,并建立中药"升降浮沉"的评价方法,通过超分子印迹模板理论对中药升降浮沉进行剖析,揭示其科学内涵,推动中药药性理论不断创新。  相似文献   
20.
Suspicious radiological findings in the jaw bone require histopathological examination for the confirmation of a diagnosis. As pathologies in this region are difficult to reach or are in close proximity to relevant anatomical structures, e.g. tooth roots or nerves, they often represent a challenge. Such factors may adversely affect the predictability of the surgical outcome of a biopsy of the osseous tissues. This technical note introduces a novel method for performing a digitally planned, guided biopsy. For this purpose, a cone beam computed tomography scan and an intraoral scan are superimposed using specific planning software. The resulting three-dimensionally printed, tooth-supported drilling template is designed for a trephine biopsy. It allows a precise, minimally invasive approach, with an exact three-dimensional determination of the biopsy location prior to surgery. The risk of devitalization of the neighbouring teeth or possible damage to the nerve structures can be minimized. Furthermore, a small access flap can be sufficient. In summary, the method of bone biopsy presented here allows high precision and greater predictability for biopsy sampling and is minimally invasive for the patient.  相似文献   
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