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61.
Anna Krahl Andreas Lipphaus Martin P. Sander Fulvio Maffucci Sandra Hochscheid Ulrich Witzel 《Anatomical record (Hoboken, N.J. : 2007)》2020,303(8):2177-2191
Adaptation of osteology and myology lead to the formation of hydrofoil foreflippers in Cheloniidae (all recent sea turtles except Dermochelys coriacea) which are used mainly for underwater flight. Recent research shows the biomechanical advantages of a complex system of agonistic and antagonistic tension chords that reduce bending stress in bones. Finite element structure analysis (FESA) of a cheloniid humerus is used to provide a better understanding of morphology and microanatomy and to link these with the main flipper function, underwater flight. Dissection of a Caretta caretta gave insights into lines of action, that is, the course that a muscle takes between its origin and insertion, of foreflipper musculature. Lines of action were determined by spanning physical threads on a skeleton of Chelonia mydas. The right humerus of this skeleton was micro-CT scanned. Based on the scans, a finite element (FE) model was built and muscle force vectors were entered. Muscle forces were iteratively approximated until a uniform compressive stress distribution was attained. Two load cases, downstroke and upstroke, were computed. We found that muscle wrappings (m. coracobrachialis magnus and brevis, several extensors, humeral head of m. triceps) are crucial in addition to axial loading to obtain homogenous compressive loading in all bone cross-sections. Detailed knowledge on muscle disposition leads to compressive stress distribution in the FE model which corresponds with the bone microstructure. The FE analysis of the cheloniid humerus shows that bone may be loaded mainly by compression if the bending moments are minimized. 相似文献
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Phoebe Hammer Kevin White Stephanie Mengden Vessy Korcheva Philipp W. Raess 《Journal of cutaneous pathology》2019,46(5):343-346
Cutaneous leiomyomas are rare benign smooth‐muscle tumors. These lesions are distinguished based on their cell of origin and are subclassified as pilar leiomyoma, angioleiomyoma, and genital‐type leiomyoma. Nipple leiomyoma is the least common genital‐type leiomyoma, arising from the dartoic muscle cell of the nipple. Histologic examination of the lesion is necessary for definitive diagnosis, and these uncommon tumors can pose a diagnostic challenge. We describe herein a series of six nipple leiomyomas with a spectrum of histologic appearances. 相似文献
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《Taiwanese journal of obstetrics & gynecology》2020,59(4):481-488
This review aimed to evaluate the short term and long-term outcomes of laparoscopic radical hysterectomy (LRH) versus abdominal radical hysterectomy (ARH) for early-stage cervical cancer. A search of PubMed, Medline and Scopus databased from 2000 to 2018 was conducted. Thirty studies were retrieved including 22 retrospective cohort studies and 8 prospective cohort studies. LRH was comparable with ARH in 5-year overall survival (RR = 1.0. 95%CI 0.98–1.03; p = 0.33) and 5-year disease-free survival (RR = 1.02 95%CI 0.97–1.06; p = 0.98). The majority of included studies reported the negative cancer factors which drive adjuvant therapy were similar between two approaches. LRH was associated with lower blood loss and blood transfusion, less postoperative complication, shorter hospital stays and similar intraoperative complication rate compared to ARH. Our data suggested LRH for early-stage cervical cancer was as safe and effective in terms of long-term outcomes, but with lower surgical morbidities. 相似文献
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Renata Maria Moreira Moraes Furlan Guilherme André Santana Mariana Souza Amaral Andréa Rodrigues Motta Estevam Barbosa de Las Casas 《Journal of oral rehabilitation》2020,47(7):872-879
Oral motor exercises, for recovering tongue strength, can be integrated with computer games to increase motivation, especially for treatments in children. The aim of this study was to investigate the influence of tongue strength on motor performance in computer games reliant on lingual force generation. An observational study was carried out at a speech-language pathology outpatient university clinic. Twenty participants (10 with normal tongue strength and 10 with reduced tongue strength) aged 8-13 years used an intra-oral joystick controlled by the tongue to play six computer games during which they had to reach targets that appeared on the screen. Motor performance was measured by the number of attempts to score and the time during which the target force was maintained. Tongue motor performance was compared between groups and across directions of tongue movement, resistance force levels, order of target appearance, continuous force application time on the target, age and sex. Children with normal tongue strength had a lower number of attempts to score (P = .014) and maintained the target force for longer periods (P = .002) than those with reduced tongue strength. The performance was better for both groups (a) in the downward direction compared with the performance in other directions, (b) in games with the lowest resistive force level (0.5 N) compared to those with other levels of resistive force and (c) in the second and third rounds compared with the first round. There were no gender-related differences in performance. Older participants performed better than younger participants. Tongue strength, direction of movement, force to reach the target, time of continuous force application, order of target appearance and age influenced tongue motor performance. 相似文献
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背景:微创全髋关节置换后难免发生并发症,目前临床常用术后评估的影像学手段多种多样,各有利弊。目的:介绍X射线片、CT、MRI等影像学检查在微创全髋关节置换后疗效评估方面的应用价值及研究进展。方法:由第一作者检索PubMed数据库、中国知网、万方数据库中2000至2020年出版的文献,英文检索词为"surgical injury,MRI,minimally invasive,muscle trauma";中文检索词为"微创全髋关节置换术,影像,评估,肌肉损伤",对微创全髋关节置换过程中不同入路的特点及其对髋周肌群影响的影像检查结果进行总结分析。结果与结论:①X射线片是全髋关节置换后患者复查的首选检查;②骨单光子发射CT不易受到金属伪影的影响,在关节置换患者中显示出更高的敏感性和特异性;③MRI成为评估髋周肌群,特别是肌肉形态学改变的金标准;④血清炎性细胞因子水平作为肌肉损伤的标志物,是评估微创全髋关节置换的一种特异而客观的方法;⑤提示微创全髋关节置换极大地避免了肌肉和肌腱的切开或剥离,减少了术后髋关节脱位及脂肪液化坏死等风险;老年患者因其肌肉修复再生能力减弱,在进行全髋关节置换过程中使用微创术式有着独特的临床价值;影像学检查能够客观准确地评估微创手术的患者获益。 相似文献
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石梅 《内蒙古医科大学学报》2022,44(5)
目的: 探讨育龄、绝经过渡期子宫肌瘤患者异常阴道出血危险因素,为异常阴道出血临床精准诊断、治疗提供理论依据。方法: 选取2017年06月—2020年06月于内蒙古医科大学附属医院住院行手术治疗的子宫肌瘤患者。实验组设为非月经期异常阴道出血的子宫肌瘤患者,对照组为无异常阴道流血子宫肌瘤患者。根据第9版教科书年龄18-43岁定为育龄组;44-54岁定为绝经过渡期组(我国妇女平均绝经年龄为49.5岁,80%在44-54岁之间〔1〕)。 应用Excel双录入,核对无误后进行统计分析。计数资料的比较用R×C列联表卡方检验、四格表卡方检验及两独立样本秩和检验。非条件Logistic回归模型用于子宫肌瘤阴道异常出血危险因素的分析,并分别得到OR值与相应95%的可信区间。在此模型中,OR值>1认为是危险因素,OR值<1认为是保护因素。统计学显著性水平设定为双侧p≤0.05,即认为差异有统计学意义。全部统计分析选用SPSS19.0软件进行统计学分析。结果:1.将与子宫肌瘤阴道异常出血相关的33项临床指标纳入单因素分析得出,月经周期异常、肌瘤位置(子宫颈肌瘤)、肌瘤直径≥9cm、血红蛋白异常、子宫内膜癌、核分裂像>5个差异有统计学意义(P≤0.05),均是子宫肌瘤阴道异常出血的危险因素;2.子宫肌瘤异常阴道出血核分裂像>5个与子宫内膜病理性改变和异常阴道出血差异有统计学意义(P=0.019)。结论:1. 子宫内膜发生病理改变是子宫肌瘤患者引起异常阴道出血的原因之一。2.月经周期异常、子宫颈肌瘤、肌瘤直径≥9cm、血红蛋白异常、子宫内膜病理改变均是子宫肌瘤阴道异常出血的危险因素;子宫肌瘤核分裂像>5个是子宫平滑肌瘤出现异常阴道出血的独立高危因素;3.子宫肌瘤核分裂像>5与阴道出血、子宫内膜病理改变有统计学意义。进行单因素分析后得知,月经周期、肌瘤位置、肌瘤大小、血红蛋白、子宫内膜病理变化均子宫肌瘤阴道异常出血的发生有关。
关键词育龄;绝经过渡期;子宫平滑肌瘤;异常阴道出血;危险因素 相似文献
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