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91.
《Respiratory investigation》2022,60(2):300-308
BackgroundIn obstructive sleep apnea (OSA), the upper airway is obstructed during sleep due to obesity and/or posterior collapse of the tongue root. Maxillofacial morphological abnormalities increase the risk of OSA in the Asian population. This study sought to elucidate whether three-dimensional (3D) photogrammetry measurements correlate with the severity of OSA irrespective of sex and degree of obesity.MethodsA prospective pilot study was performed, in which 37 consecutive adult patients (M/F = 28/9) underwent polysomnography and 3D photogrammetry in the supine position for the diagnosis of OSA. Measurements obtained from 3D photogrammetry included mandibular width (Mw), mandibular length (Ml), mandibular depth (Md), mandibular width–length angle (Mwla), and mandibular area (Ma). The effects of sex and body mass index (BMI) on the measurements and their association with the apnea–hypopnea index (AHI) were statistically analyzed. The inter-rater reliability of the measurements was evaluated using intraclass correlation coefficients (ICC).ResultsMwla (R = 0.73, p < 0.01), Mw (R = 0.39, p < 0.05), and Md (R = ?0.34, p < 0.05) were significantly correlated with the severity of OSA. On multivariate analysis, Mwla (p < 0.01) and Md (p < 0.05) remained independent factors for AHI after adjusting for sex, age, BMI, and neck circumference. In addition, diagnosability analysis revealed that Mwla was useful for identifying the presence of OSA (AHI ≥5) (cutoff: 78.6°, sensitivity: 0.938, specificity: 0.800, area under the curve: 0.931). The ICC was >0.9, showing high reliability.ConclusionsThis study suggests that Mwla measured using 3D photogrammetry can predict the presence of OSA and correlates with the severity of OSA, independent of obesity and sex. 相似文献
92.
Human vascular endothelial cells with extended life spans: in vitro cell response,protein expression,and angiogenesis 总被引:4,自引:0,他引:4
Gagnon E Cattaruzzi P Griffith M Muzakare L LeFlao K Faure R Béliveau R Hussain SN Koutsilieris M Doillon CJ 《Angiogenesis》2002,5(1-2):21-33
An in vitro angiogenesis system was designed for screening angiogenic agonists and antagonists. In order to obtain large quantities of cells and reproducibility, human endothelial cells with extended life spans were developed by retroviral transfection. The resulting cells grown in a serum-free medium containing endothelial cell growth supplement (ECGS) have a telomerase activity, extended life spans of at least 21 passages, and an endothelial cell phenotype (diI-acetylated-LDL upake, factor VIII-related antigen, VEGFR-1 and R-2, and tissue-type plasminogen activator (tPA)) that resembled that of unaltered primary endothelial cells. Exceptions were (i) a higher expression of tPA, and (ii) a non-significant growth response to FGF-2 or VEGF stimulation. Within three-dimensional fibrin gels, specific cell clones rapidly formed tubular structures in a more reproducible manner than those observed with low-passage primary cells. Tube formation by primary endothelial cells and those with extended life spans was dependent upon FGF-2 and ECGS, respectively. Both cell types produced FGF-2 and VEGF cytokines. Increasing doses of suramin significantly decreased the size of microvessels formed by both cell lines. These functional results indicate that a vascular matrix system containing human cells with extended life spans can be successfully utilized as an in vitro assay for antiangiogenic compounds. 相似文献
93.
Reddy VK Nanda S Bandarupalli N Pothineni KR Nanda NC 《Echocardiography (Mount Kisco, N.Y.)》2008,25(6):653-657
We describe a patient with blunt traumatic chest injury in whom three-dimensional transthoracic echocardiography (3DTTE) confirmed the findings of a flail anterior tricuspid valve leaflet and ruptured anterior papillary muscle seen on two-dimensional transthoracic echocardiography, and in addition identified multiple chordae tendinae rupture of the posterior leaflet. Open heart surgery confirmed the findings. The emerging role of 3DTTE in defining the true extent of traumatic tricuspid valvular injury is highlighted . 相似文献
94.
Assessment of atrial septal defect size with 3D-transesophageal echocardiography: comparison with balloon method 总被引:4,自引:0,他引:4
Abdel-Massih T Dulac Y Taktak A Aggoun Y Massabuau P Elbaz M Carrié D Acar P 《Echocardiography (Mount Kisco, N.Y.)》2005,22(2):121-127
BACKGROUND: Transcatheter closure of atrial septal defect (ASD) is an alternative approach to surgery in selected patients. Balloon stretched diameter (BSD) is considered as the standard way of measuring ASD size. Three-dimensional transesophageal echocardiography (3D-TEE) provides views of the ASD allowing its measurement and identifying its spatial relation with neighboring structures. Our aim was to compare the BSD and 3D-TEE methods to measure the ASD size before transcatheter closure. METHODS AND RESULTS: Seventy-six consecutive patients were enrolled for ASD device closure. Three-dimensional transesophageal echocardiography and balloon sizing were adequately performed in 70 patients before the defect closure. The mean maximal diameter measured by 3D-TEE was 20 +/- 15 mm (range 10-28) while the mean BSD was 22 +/- 4.8 mm (range 9-31). When comparing the 3D-TEE and transcatheter measurements, there was a good correlation between the two methods (y = 3.15 + 0.77x; r = 0.8). The defect as viewed by 3D-TEE was unique in 54 patients and multiple in 16 patients. In patients with a single defect, the correlation between the two methods was high (y = 1.74 + 0.84x; r = 0.85) while patients with multiple ASDs, the correlation was poor (y = 12.4 + 0.4x; r = 0.45). Transcatheter closure was performed successfully in 86%. The mean size of the Amplatzer device was 23 +/- 4.8 mm (range 4-32). The reference to choose the size of the device was the BSD in single defects and the 3D-TEE maximal diameter in multiple defects. CONCLUSION: Three-dimensional transesophageal echocardiography and transcatheter methods are two complementary techniques for the success of transcatheter ASDs closure. 相似文献
95.
We propose a spinning-assisted layer-by-layer method for simple fabrication of a multilayered polymer hydrogel membrane that contains living cells. Hydrogel formation occurred based on the spontaneous cross-linking reaction between two polymers in aqueous solution. A water-soluble 2-methacryloyloxyethyl phosphorylcholine polymer bearing phenylboronic acid groups (PMBV) and poly(vinyl alcohol) (PVA) were used as polymers for hydrogel membrane formation. Changing the number of hydrogel membrane layers, polymer concentration, spinning rate, and processing time for diffusion-dependent gelation of PMBV and PVA facilitated the regulation of the multilayered polymer hydrogel membrane thickness and morphology. We concluded that a multilayered polymer hydrogel membrane prepared using 5.0 wt% PMBV and 5.0 wt% PVA at a spinning rate of 2000 rpm was suitable for precise spatial control of cells in single layers. This multilayered polymer hydrogel membrane was used to prepare a single cell-laden layer to minimize barriers to the diffusion of bioactive compounds while preserving the three-dimensional (3-D) context. The pharmaceutical effects of one of the anticancer agents, paclitaxel, on a human cervical cancer line, HeLa cells, were evaluated in vitro, and the usability of this culture model was demonstrated. 相似文献
96.
Zhen-Yu Wu Young Joo Lee Yungil Shin Soojeong Choi Soo Yeon Baek Jung Whan Chun Loai Saleh Albinsaad Woo Jung Choi Namkug Kim BeomSeok Ko 《JOURNAL OF BREAST CANCER》2021,24(3):349
Tumor localization is challenging in the context of ductal carcinoma in situ (DCIS) treated with breast-conserving surgery. Conventional localization methods are generally performed under the guidance of ultrasonography or mammography and are rarely performed with magnetic resonance imaging (MRI), which is more sensitive than the aforementioned modalities in detecting DCIS. Here, we report the application of MRI-based individualized 3-dimensional (3D)-printed breast surgical guides (BSGs) for patients with breast cancer. We successfully resected indeterminate and suspicious lesions that were only detected using preoperative MRI, and the final histopathologic results confirmed DCIS with clear resection margins. MRI guidance combined with 3D-printed BSGs can be used for DCIS localization, especially for lesions easily detectable using MRI only. 相似文献
97.
98.
目的 应用三维有限元法分析不同修复方法对深型楔状缺损牙应力分布的影响。方法 选择上海市口腔病防治院门诊患者因正畸拔除的下颌第一前磨牙1颗作为研究样本,通过Micro-CT扫描并联合应用4种软件模拟重建下颌第一前磨牙深型楔状缺损模型,模型分别用复合树脂和瓷嵌体两种材料修复,洞形制备分为有倒凹和无倒凹两种方法。加载200 N垂直载荷后应用有限元分析软件进行应力分析。结果 牙颈部楔状缺损修复后其颈部牙体组织等效应力显著降低,其中采用全瓷嵌体修复缺损的模型颈部牙体组织等效应力降低最多。各模型修复体位移和颊尖位移均无明显差异。Ⅲ度楔状缺损各修复模型中,单纯采用树脂修复模型的修复体等效应力和最大应力均低于其他两种模型。Ⅳ度楔状缺损各修复模型中,采用全瓷嵌体修复模型的修复体等效应力和最大应力均显著低于其他两种模型,采用树脂修复的两个模型其修复体等效应力之间无明显差异。结论 修复治疗可缓解楔状缺损牙缺损区的牙体硬组织应力集中。Ⅲ度楔状缺损可采用树脂修复;Ⅳ度楔状缺损推荐优先选择全瓷嵌体修复,树脂修复则建议增加固位倒凹。 相似文献
99.
目的应用3dMD?面部三维成像系统研究拔牙矫治对青少年骨性Ⅰ类错
畸形面部软组织三维特征的影响,为正畸矫治提供参考。
方法选取2016—2019年期间于中山大学附属口腔医院正畸科就诊的青少年骨性Ⅰ类患者50例,其中拔牙组25例,非拔牙组25例为对照组,应用3dMD?收集正畸治疗前后的面部三维图像数据,通过3dMD? vultus软件测量线距、角度、体积变化,应用SPSS 20.0统计分析软件对各项测量指标的比较采用独立样本t检验。
结果正畸治疗后,在线距方面,拔牙组、非拔牙组前下面高变化量分别为(0.28 ± 2.28)、(1.85 ± 2.18)mm,差异有统计学意义(t = -2.238,P = 0.031);拔牙组下颌高、颏高、唇宽变化量分别为(-0.52 ± 2.31)、(-1.14 ± 2.64)、(-1.33 ± 3.62)mm,非拔牙组则分别为(1.64 ± 2.42)、(0.93 ± 2.51)、(1.40 ± 2.16)mm,差异有统计学意义(t下颌高 = -2.878,P下颌高 = 0.007;t颏高 = -2.506,P颏高 = 0.017;t唇宽 = -2.942,P唇宽 = 0.006)。在角度方面,拔牙组、非拔牙组鼻唇角变化量分别为4.91° ± 3.12°、1.50° ± 4.26°,差异有统计学意义(t = 2.692,P = 0.011);拔牙组、非拔牙组颏唇角变化量分别为-0.24° ± 6.83°、4.82° ± 6.50°,差异有统计学意义(t = -2.373,P = 0.023);拔牙组、非拔牙组唇角变化量分别为-16.80° ± 12.65°、-1.04° ± 11.24°,差异有统计学意义(t = -4.171,P<0.001)。在体积方面,拔牙组、非拔牙组唇部变化量分别为(-0.66 ± 1.24)、(0.46 ± 1.43)cm3,差异有统计学意义(t = -2.584,P = 0.014);拔牙组、非拔牙组颏部变化量分别为(-0.16 ± 0.94)、(0.65 ± 0.91)cm3,差异有统计学意义(t = -2.766,P = 0.009)。
结论(1)拔牙与非拔牙矫治对患者面下1/3水平向无明显影响,但对面下1/3的垂直向影响有差异,非拔牙较拔牙矫治更易导致面部高度的增加;(2)开唇露齿的青少年患者经拔牙矫治可有效改善颏、唇部形态;(3)对于面部消瘦、颧部凸出的患者,应慎重拔牙矫治。 相似文献
100.