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71.
Background:Vertical pelvic ring displacement (VPRD) is a serious injury and needs assessment. Pelvic outlet radiographs are routinely taken. However, relationship of radiographic and actual VPRD is still in question. Thus, measurement of VPRD from pelvic radiographs was studied.Results:Radiographic VPRD from outlet and anteroposterior pelvic views at 10 mm actual displacement were 20.12 ± 1.98 and 4.08 ± 3.76 mm, at 20 mm were 40.31 ± 1.97 and 9.94 ± 7.27 mm and at 30 mm were 58.56 ± 2.53 and 11.29 ± 2.89 mm. Statistical analyses showed that radiographic VPRD from pelvic outlet view is 1.95 times of actual displacement with strong correlation at 0.992 coefficient and strongly significant regression analysis (P < 0.001) with 0.984 of R2 value. Whereas, the measurement from anteroposterior pelvic radiograph was not strongly significant.Conclusion:Pelvic outlet radiograph provides efficient measurement of VPRD with 2 times of actual displacement.  相似文献   
72.
Patients with obstructed total anomalous pulmonary venous connection (TAPVC) usually present critically ill and continue to be extremely challenging with presurgical stabilization. We present an extra corporeal membrane oxygenation (ECMO)-dependent neonate with obstructed TAPVC that was successfully palliated with transvenous stent placement in the obstructed vertical vein.  相似文献   
73.
目的 观察α相与β相主牙胶尖在热垂直加压充填法中对根尖区的三维封闭作用.方法 实验筛选出根尖区4mm具有侧支根管或根尖分歧的下颌第一前磨牙20颗,以镍钛根管锉ProtaPer冠向下法预备至F3,将20例样本随机分为2组,分别采用α相牙胶与β相牙胶,以热垂直加压根管充填技术进行根管充填.充填完成前、后采用微计算机断层扫描技术对根尖区4mm容积进行扫描及三维重建,计算根尖区4mm充填程度即充填后容积与充填前容积之比,观察2种不同相的主牙胶尖对根尖区的封闭效果.结果 2种牙胶的根尖区充填程度均在81%以上,α相牙胶组在根尖区的充填程度与β相牙胶组差异无统计学意义.结论 α相牙胶组与β相牙胶组均对根尖区有良好的三维封闭效果,二者无显著性差异.  相似文献   
74.

Objectives

The aim of the present study was to evaluate whether extracellular volume fraction (ECV) can reliably inform on the extent of diffuse fibrosis in the simultaneous presence of myocardial inflammation, which has not been verified to date.

Background

Diffuse myocardial fibrosis is associated with unfavorable outcome in patients with cardiomyopathy, and is of prognostic relevance. Assessment of ECV bears promise for being a noninvasive surrogate parameter, but it may be altered by other pathologies.

Methods

In this prospective study, 107 consecutive patients with clinical suspicion of inflammatory cardiomyopathy were included. All patients underwent left ventricular (LV) endomyocardial biopsy (EMB) and cardiac magnetic resonance imaging on a 1.5-T scanner. T1 mapping was obtained with the modified Look-Locker inversion recovery sequence, and ECV was calculated.

Results

Myocardial inflammation was present in 66 patients. Patients with and without inflammation were of similar age and had comparable LV ejection fraction (37 ± 17% vs. 36 ± 18%; p = 0.9) and symptom duration (median 14 days [interquartile range: 5 to 36 days] vs. median 14 days [interquartile range: 7 to 30 days]; p = 0.73). Although LV collagen volume percentage was comparable between groups (inflammation 12.3 ± 17.8% vs. noninflammation 11.4 ± 7.9%; p = 0.577), ECV was significantly higher in patients with inflammation (0.37 ± 0.06%) than in those without inflammation (0.33 ± 0.08%; p = 0.02). Importantly, ECV adequately estimated the degree of LV fibrosis percentage only in patients without inflammation (r = 0.72; p < 0.0001) and not in those with inflammation (r = 0.24; p = 0.06).

Conclusions

These findings prove the theoretical concept of ECV as an estimate for diffuse myocardial fibrosis, but only in the absence of significant myocardial inflammation. Assuming that various degrees of myocardial inflammation and fibrosis coexist in such a scenario, the measured ECV will reflect a sum of these different pathologies but will not inform solely on the extent of diffuse fibrosis.  相似文献   
75.
Direct‐acting antivirals (DAAs) for HCV treatment have improved tolerance and efficacy among adults, but experience in vertical transmission is scarce. In our vertically HIV/HCV co‐infected youth cohort of 58 patients, DAA achieved excellent rates of cure among naïve and pretreated individuals. Treating vertically infected seems important as 29.6% displayed advanced fibrosis at treatment initiation.  相似文献   
76.
The synthesis of high‐aspect‐ratio (AR) CdSe (NRs) nanorods and their ordered assembly over large areas are reported. Long‐range ordering of hexagonal arrays of high‐AR NRs is achieved by a combination of controlled solvent evaporation and the use of an applied electric field. Vertically oriented assemblies of CdSe NRs functionalized with oligo‐ and polythiophene are also obtained. Aligned and oriented polythiophene CdSe NRs have potential applications in organic–inorganic hybrid bulk‐heterojunction photovoltaic devices.

  相似文献   

77.
根管预备的工作宽度是指根管应该被扩大的程度。适宜的工作宽度是在尽可能保存牙体组织的前提下,彻底去除根管内的感染源,达到最佳的清理和成形效果。由于根管解剖形态的多样性以及根管内感染的复杂性,对于根管预备的工作宽度尚无明确定论,文章就根管预备的工作宽度做一介绍。  相似文献   
78.
随着种植外科的进展,大量垂直向和水平向骨增量技术得到了发展。许多种植患者存在垂直向骨量不足的问题,需要增加垂直向骨量;但垂直向骨增量相对于水平向骨增量难度比较大,预见性较差,往往易致较多的并发症;因此,垂直向骨增量技术受到了越来越多的关注。引导骨再生技术和牵张成骨术是2类较常用的垂直向骨增量技术,在临床上已得到一定的应用,本文对其在垂直向骨增量上的研究进展作一综述。  相似文献   
79.
Abstract – Root fracture diagnosis is a clinical difficulty that in most cases can only be detected through radiography. The objective of this study was to compare the diagnostic accuracy of two types of digitally enhanced images (reverse‐contrast and colorization) with original digital radiographies in detecting experimental root fractures. Two hundred extracted single‐rooted human teeth were endodontically instrumented and then divided in two groups, one control group and one test group, including fractured teeth. Vertical root fractures were experimentally made in the fractured group. The digital image of each tooth was taken, using the paralleling technique. There were three groups of images: (i) original, (ii) reverse contrast, and (iii) colorized. Three experienced dental specialists examined the images with no prior knowledge of the distribution of the root fractures. Two‐way analysis of variance was used to assess the differences in accuracy, sensitivity, and specificity of each technique in detecting root fractures. Cohen’s kappa coefficients were calculated to investigate the degree of interobserver agreement. The accuracy, sensitivity, and specificity of original images were 67.4%, 66.7%, and 68%, respectively; these amounts were 61.5%, 61%, and 65.5% in reverse contrast images and 66.4%, 70.7%, and 62% in colorized digital radiography. The original images had the best inter observer kappa coefficients (between 0.45 and 0.55). The results showed that the accuracy of original images is better than reverse contrast and colorized images. Use of reverse‐contrast and colorization digital images in root fracture detection should be regarded as an adjunct to other diagnostic methods not as a highly critical diagnostic aid.  相似文献   
80.
目的研究垂直生长型安氏Ⅱ类1分类青少年与成人硬组织在矫治前后的变化,以期为正畸临床治疗方案的制定和治疗方法提供参考。方法选择38例垂直生长型安氏Ⅱ类1分类拔牙病例,在矫治前后拍摄X线头颅侧位片,对39个硬组织测量指标进行测量,并对青少年与成人矫治前后的变化量进行比较。结果研究对象矫治后ANB角、NA-PA、U1-FH、U1-NA、U1-Ptm、Spr-Ptm、Id-Go等青少年组与成人组的变化差异有统计学意义;Pog-Go、Cd-Go、S-Go、N-Me等都分别有所增加;与青少年组的OP-FH在正畸治疗后的减小相比较,成人组的OP-FH有所增加,成人组的平面发生了顺时针旋转。结论青少年在正畸治疗中表达更多的骨效应,即青少年通过正畸治疗能够更大程度地改善其Ⅱ类骨面型,更有利于其侧貌美观的改善;青少年上颌磨牙的伸长量基本是在有益的范围内,结合下颌升支等后面高的发育,能够使下颌平面、平面发生逆时针旋转,这对于垂直生长型Ⅱ类1分类病例的正畸治疗和面型改善以及治疗效果的稳定是有利的,同时也提示了垂直生长型Ⅱ类1分类错畸形的正畸治疗最佳时间为生长发育时期。  相似文献   
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