linear measurements

线性测量
  • 文章类型: Journal Article
    目的:评估上埃及不同骨骼畸形个体的蝶鞍(ST)形态。
    方法:300位成年男女患者的侧位头颅X光片,年龄从18岁到30岁不等,被选择并分为三个相等的组,组(1):骨骼I类(对照组),组(2):骨骼II类,和组(3):骨骼III类。治疗前侧位脑电图取自正畸科的档案,牙科学院,米尼亚大学。结节和背蝶鞍,ST的地板,并绘制后前斜突(ACPs)。直接测量,如直径(APD),深度(D),使用Silverman和Kisling方法测量蝶鞍的长度(L)。
    结果:在深度(D)方面发现了I类和II类之间的显着差异,II类具有更大的深度。此外,最大直径(APD)在III类组中发现。两个年龄组(18至24岁和25至30岁)之间的直径(APD)存在显着差异。结论:在骨骼III类受试者中看到较大的直径值,而在II类受试者中观察到较大的深度值。年龄较大的年龄组(25-30岁)的直径比年龄较小的年龄组大。两性之间在长度和深度上发现了非常显着的差异。
    OBJECTIVE: To evaluate the morphology of sella turcica (ST) in individuals with different skeletal malocclusions in upper Egypt.
    METHODS: 300 lateral cephalometric radiographs of adult patients of both sexes, varying ages from 18 to 30 years, were selected and divided into three equal groups, group (1): skeletal class I (control group), group (2): skeletal class II, and group (3): skeletal class III. Pre-treatment lateral cephalograms were taken from the archives of the Department of Orthodontics, Faculty of Dentistry, Minia University. The tuberculum and dorsum sella, the floor of ST, and posterior and anterior clinoid processes (ACPs) were drawn. The direct measurements such as diameter (APD), depth (D), and length(L) of sella were measured using Silverman and Kisling methods.
    RESULTS: A significant difference was found in depth (D) between class I and class II, with class II having a greater depth. Also, the largest diameter (APD) was found in the class III group. A significant difference was found in diameter (APD) between the two age groups (from 18 to 24 years and from 25 to 30 years) Conclusion: The larger diameter values were seen in the skeletal class III subjects, while the larger depth values were observed in the class II subjects. The older age group (25-30 years) has a greater diameter than the younger one. Highly significant differences were found in length and depth between the sexes.
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  • 文章类型: Journal Article
    单峰骆驼(Camelusdromedarius)胎膜,通常被称为“胎盘”,是上皮神经,弥漫,和微子叶,类似于母马的胎盘。胎盘的评估是马种新生儿评估的重要组成部分。然而,不幸的是,单峰骆驼的产后或流产后胎盘评估经常被忽视,据作者所知,单峰骆驼缺乏对正常胎盘总体形态的全面描述。为了促进其实地评估,本研究描述了足月妊娠和自然分娩后单峰骆驼胎盘的宏观特征。
    The dromedary camel (Camelus dromedarius) fetal membranes, commonly referred to as \"the placenta\", are epitheliochorial, diffuse, and microcotyledonary, similarly to the mare\'s placenta. The evaluation of the placenta is an essential component of the neonatal evaluation in the equine species. However, post-partum or post-abortion placental assessment in dromedary camels is unfortunately too frequently neglected and, to the best of the authors\' knowledge, the dromedary camel species lacks a comprehensive description of the normal placenta\'s gross morphology. In order to facilitate its on-field evaluation, the current study describes the macroscopic features of the placenta of the dromedary camel after full-term pregnancy and spontaneous parturition.
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  • 文章类型: Journal Article
    在三叶草中,查加斯病的媒介,主动扩散是通过步行和飞行进行的。飞行比步行受到更多的关注,尽管最后一种是若虫由于缺少翅膀而使用的散布方式,也被成年人使用,这将有助于在病媒控制措施后对房屋进行定殖和再侵扰。本工作研究了Triatoma感染腿的形态计量学变化,南美南锥体锥虫病的主要病媒。我们描述了形态特征和每个腿段的自然变异。不同的线性,使用形态计量学工具分析了T.infestans第五龄若虫的三条右腿的每个组成部分的大小和形状变量。我们分析了差异,整个前段的变化和相关性,使用不同的统计方法,如一般线性模型,规范变量分析,变异系数的相等性检验和偏最小二乘分析。我们还通过偏最小二乘和形态差异分析分析了每条腿内各段之间的变化和相关性。我们的结果表明,两腿之间的节段不同,作为总趋势,尺寸(长度,宽度和/或大小)在后腿中更大,前腿较小,中间腿较小。股骨和胫骨(长度和/或宽度)显示出腿部之间的形态变化差异,股骨和胫骨显示出腿部之间的最高相关性。另一方面,在前腿和中腿,股骨(长度或宽度)表现出类似的变化与胫骨和关节的长度,但在后腿上,股骨显示所有节段相似的变化,而不是胫骨长度,并且每条腿内的线性测量之间存在很强的相关性。我们的结果表明,股骨和胫骨可以在决定行走方式的双腿之间的协调中起决定性作用。考虑到这些段也将与每条腿具有的特定功能相关联,这项研究表明,股骨和胫骨在T.infestans的步行运动中起着重要作用。
    In triatomines, vectors of Chagas disease, active dispersal takes place by walking and flying. Flight has received more attention than walking although the last is the dispersal modality used by nymphs due to their lack of wings and also used by adults, which would facilitate the colonization and reinfestation of houses after vector control actions. The present work studied the morphometrical variation of Triatoma infestans legs, the main vector of Chagas disease the Southern Cone of South America. We described morphometric traits and the natural variation of each leg segment. Different linear, size and shape variables of each component of the three right legs of fifth instar nymphs of T. infestans were analyzed using morphometric tools. We analyzed differentiation, variation and correlation for each segment across the fore-, mid and hind legs using different statistical approaches such as general linear model, canonical variates analysis, test of equality of coefficient of variation and partial least square analysis. We also analyzed variation and correlation between segments within each leg with partial least square and morphometric disparity analyses. Our results showed that the segments differed between legs, as general trends, the dimensions (length, width and/or size) were greater in the hind legs, smaller in the forelegs and intermediate in the mid ones. The femur and tibia (length and/or width) showed differences in morphometric variation between legs and the femur and tibia showed the highest levels of correlation between legs. On the other hand, in the fore- and mid legs, the femur (length or width) showed similar variation with tibia and tarsus lengths, but in the hind legs, the femur showed similar variation with all segments and not with the tibia length, and there were strong correlations between linear measurement within each leg. Our results suggest that the femur and tibia could play a determining role in the coordination between the legs that determines the walking pattern. Considering that these segments would also be linked to the specific function that each leg has, this study suggests a preponderant role of the femur and tibia in the walking locomotion of T. infestans.
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  • 文章类型: Review
    背景:前庭神经鞘瘤(VS)的大小是指导最初决定治疗以及肿瘤控制或失败定义的主要因素。准确的测量和标准化的定义是强制性的,但没有标准存在。已经报道了使用线性测量或分段体积的各种近似方法。我们回顾了不同的容量测量方法,并使用我们自己的历史队列评估了它们的相关性和一致性。
    方法:我们选择了在我们部门通过伽玛克尼夫放射外科(GKRS)治疗散发性VS的患者。在GKRS当天使用立体定向3DT1增强MRI,4种使用线性测量的容积测量方法(5轴,3轴,3轴平均,和1轴)和分段容量相互比较。使用组内相关性检验(ICC3,1)评估相关性程度。使用Bland-Altman图评估了不同方法之间的一致性。
    结果:共纳入2,188例患者。我们观察到5轴容量(0.98)之间有一个很好的ICC,3轴容积测量(0.96),和3轴平均容积(0.96)和分段容积,分别,无论Koos等级或Ohata分类。单轴容量的ICC较低(0.72),并且根据Koos和Ohata亚组的不同而变化。这些方法都不是可替代的。
    结论:虽然节段容积法被认为是最准确的方法,与使用线性测量的体积法相比,它需要更多的努力,并且需要复杂的计算系统。在评估的所有方法中,5轴容积法提供了分段容积法的最佳充分性,无论肿瘤的形状如何。不应使用单轴容积法。
    The size of vestibular schwannomas (VS) is a major factor guiding the initial decision of treatment and the definition of tumor control or failure. Accurate measurement and standardized definition are mandatory; yet no standard exist. Various approximation methods using linear measures or segmental volumetry have been reported. We reviewed different methods of volumetry and evaluated their correlation and agreement using our own historical cohort.
    We selected patients treated for sporadic VS by Gammaknife radiosurgery (GKRS) in our department. Using the stereotactic 3D T1 enhancing MRI on the day of GKRS, 4 methods of volumetry using linear measurements (5-axis, 3-axis, 3-axis-averaged, and 1-axis) and segmental volumetry were compared to each other. The degree of correlation was evaluated using an intraclass correlation test (ICC 3,1). The agreement between the different methods was evaluated using Bland-Altman diagrams.
    A total of 2,188 patients were included. We observed an excellent ICC between 5-axis volumetry (0.98), 3-axis volumetry (0.96), and 3-axis-averaged volumetry (0.96) and segmental volumetry, respectively, irrespective of the Koos grade or Ohata classification. The ICC for 1-axis volumetry was lower (0.72) and varied depending on the Koos and Ohata subgroups. None of these methods were substitutable.
    Although segmental volumetry is deemed the most accurate method, it takes more effort and requires sophisticated computation systems compared to methods of volumetry using linear measurements. 5-axis volumetry affords the best adequacy with segmental volumetry among all methods under assessment, irrespective of the shape of the tumor. 1-axis volumetry should not be used.
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  • 文章类型: Journal Article
    使用基于火腿横截面的数字图像分析来测量248个火腿中的两个瘦肌肉和三个皮下脂肪位置。使用两个选定脂肪位置的线性测量来预测双能X射线(DXA)脂肪或瘦肉百分比,逐步回归公式中的预测精度(R2)为0.7。基于预测方程建立了分类系统,线性测量旨在对DXA脂肪百分比(>32.0%)和瘦肉百分比(<60.2%)的第10百分位数阈值处的极端情况进行分类。当使用DXA脂肪或瘦肉百分比时,瘦火腿预测准确率下降了18%,但是当阈值从第10百分位数更改为第30百分位数时,脂肪火腿的预测准确性提高了60%。这种分类方法有可能转化为手动工具,并具有多种有用的应用,可用于商业猪肉加工者。
    Digital image analysis based on the ham cross-sectional face was used to measure two lean muscle and three subcutaneous fat locations from 248 bone-in hams. Linear measurements of the two selected fat locations were used to predict dual-energy X-ray (DXA) fat or lean percentages with prediction accuracies (R2) of 0.7 in a stepwise regression eq. A classification system was built based on the prediction equations, and the linear measurements aimed to classify extremes at the threshold of the 10th percentile of DXA fat percentage (> 32.0%) and lean percentage (< 60.2%). When using either DXA fat or lean percentage, lean ham prediction accuracy dropped by 18%, but fat ham prediction accuracy increased by 60% when the threshold was changed from the 10th percentile to the 30th percentile. This classification approach has the potential to be converted into a manual tool with several useful applications for commercial pork processors.
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  • 文章类型: Journal Article
    马的形态特征的测量对于确定品种资格很重要,并且是该物种的主要选择标准之一。由加性遗传值加权的主成分组成的指数(HPC)的开发允许使用减少数量的变量来探索最相关的关系,这些变量解释了数据中最大的变化量。使用HPC的全基因组关联研究(GWAS)是一种相对较新的方法,可以识别与一组性状相关的区域。这项研究的目的是使用HPC进行15个线性测量作为解释变量的GWAS,以识别相关的基因组区域并阐明与Campolina马中该指数相关的生物学机制。对于GWAS,加权单步GBLUP应用于HPC。确定了解释加性遗传变异比例最高的八个基因组窗口。由八个窗口解释的加性方差的总和为95.89%。确定了参与骨骼和软骨发育的基因(SPRY2,COL9A2,MIR30C,HEYL,BMP8B,LTBP1,FAM98A,和CRIM1)。它们代表所评估的线性测量的HPC的潜在位置候选。HPC是减少Campolina马中通常测量的15种性状的有效替代品。此外,在解释HPC高加性方差的区域中插入的候选基因被鉴定,并且可能被精细定位以搜索推定的突变/标记。
    The measurement of morphometric traits in horses is important for determining breed qualification and is one of the main selection criteria for the species. The development of an index (HPC) that consists of principal components weighted by additive genetic values allows to explore the most relevant relationships using a reduced number of variables that explain the greatest amount of variation in the data. Genome-wide association studies (GWAS) using HPC are a relatively new approach that permits to identify regions related to a set of traits. The aim of this study was to perform GWAS using HPC for 15 linear measurements as the explanatory variable in order to identify associated genomic regions and to elucidate the biological mechanisms linked to this index in Campolina horses. For GWAS, weighted single-step GBLUP was applied to HPC. The eight genomic windows that explained the highest proportion of additive genetic variance were identified. The sum of the additive variance explained by the eight windows was 95.89%. Genes involved in bone and cartilage development were identified (SPRY2, COL9A2, MIR30C, HEYL, BMP8B, LTBP1, FAM98A, and CRIM1). They represent potential positional candidates for the HPC of the linear measurements evaluated. The HPC is an efficient alternative to reduce the 15 usually measured traits in Campolina horses. Moreover, candidate genes inserted in region that explained high additive variance of the HPC were identified and might be fine-mapped for searching putative mutation/markers.
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  • 文章类型: Journal Article
    尽管锥形束计算机断层扫描(CBCT)在牙科种植计划中很受欢迎,无牙脊的水平近端空间仍然是传统的测量用手持滑动卡尺在口腔或石膏模型。在种植计划中的临床应用,我们的目的是评估CBCT水平近端线测量的准确性,与传统的直接测量石膏模型相比.在一项前瞻性临床研究中,分析了27例邻近下颌骨后部植入物的术后CBCT采集和石膏模型。在CBCT图像上,两名观察者在轴向和矢状视图上评估了植入物之间的距离。在石膏模型上,植入物间距用数字卡尺测量.CBCT测量轴向和矢状视图,平均而言,比石膏模型上的测量值大0.2mm。观察者在CBCT图像和石膏模型上进行的相同植入物间距离的测量之间的相关性是完美的。与传统的直接测量石膏模型相比,CBCT将两个植入物之间的水平近端测量值略微高估(平均0.2mm)作为参考点。CBCT成像足够准确,可以评估轴向和矢状视图上的近远端距离,以在临床实践中进行牙种植计划。
    Althouh cone beam computed tomography (CBCT) is popular for dental implant planning, the horizontal mesiodistal space of the edentulous ridge is still conventionally measured with a handheld sliding caliper in the oral cavity or on a plaster cast. For clinical application in implant planning, our aim was to evaluate the accuracy of CBCT horizontal mesiodistal linear measurements in comparison with conventionally obtained direct measurements on plaster casts. Postoperative CBCT acquisitions and plaster casts of 27 patients with adjacent posterior mandibular implants were analyzed in a prospective clinical study. On CBCT images, two observers assessed the inter-implant distances on axial and sagittal views. On plaster casts, the inter-implant distances were measured with a digital caliper. CBCT measurements on axial and sagittal views were, on average, 0.2 mm larger than measurements on plaster casts. Correlation was perfect between measurements of the same inter-implant distance performed by the observers on CBCT images and on plaster casts. When compared with conventionally obtained direct measurements on plaster casts, CBCT views slightly overestimated (mean 0.2 mm) the horizontal mesiodistal measurements between two implants as reference points. CBCT imaging is sufficiently accurate to evaluate mesiodistal distances on axial and sagittal views for dental implant planning in clinical practice.
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  • 文章类型: Journal Article
    Purpose: Our study aimed to determine the possible differences in linear measurements and linear indices values of intracranial fluid spaces (IFS) between right- and left-handed adults.Methods: This work has been carried out on 148 subjects (72 men and 76 women). In the study, 88 right-handers and 60 left-handers were included. Forty of the right-handers were male, 48 were female, and 32 of the left-handers were male, and 28 were female. The ages were between 20 and 50 years. Linear measurements were obtained based on magnetic resonance imaging (MRI) studies. A 1.5-T MRI scanner was used to obtain axial images. The ten parameters were estimated from MRI scans.Results: There was no correlation between parameters and age. In our study, interestingly, as can be seen from the tables, most of the parameters with statistically significant differences were higher in favour of left-handed subjects. In most of the linear measurement results, IFS values of the right hemisphere in right-handers, and the left hemisphere in left-handers were higher. Similar results were found in favour of the left-handed in most of the linear ventricular indices.Conclusion: Linear measurements and linear indices values of IFS were mostly higher in left-handers than in right-handed individuals.
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  • 文章类型: Journal Article
    背景:评估从缝合锥形束计算机断层扫描(CBCT)图像获得的线性测量结果是否与直接颅骨测量结果一样准确。方法:在参考点处用gutta-percha标记9个干燥的人类头骨,以在每个头骨上获得22个线性测量值。颅尾平面的十次测量,前后平面的两次测量,在中侧面进行十次测量。测量使用缝合软件获得的CBCT线性测量值,并与直接颅骨测量值进行比较。结果:直接线性测量和拼接CBCT图像上的线性测量之间的绝对Dahlberg误差范围为(0.07mm至0.41mm)。相对Dahlberg误差范围为(0.2%至1.8%)。此外,类内相关系数(ICC)范围为(0.97至1.0),表明一致性很好。结论:缝合CBCT线性测量与使用数字卡尺的直接颅骨测量高度可比。
    Background: To assess whether the linear measurements obtained from stitched cone beam computed tomography (CBCT) images were as accurate as the direct skull measurements. Methods: Nine dry human skulls were marked with gutta-percha at reference points to obtain Twenty-two linear measurements on each skull. Ten measurements in the cranio-caudal plane, two measurements in the antero-posterior plane, and ten measurements in the medio-lateral plane. CBCT linear measurements obtained using stitching software were measured and compared with direct skull measurements. Results: The absolute Dahlberg error between direct linear measurements and linear measurements on stitched CBCT images ranged from (0.07 mm to 0.41 mm). The relative Dahlberg error ranged from (0.2% to 1.8%). Moreover, Intra-class Correlation Coefficient (ICC) ranged from (0.97 to 1.0) indicating excellent agreement. Conclusion: Stitched CBCT linear measurements were highly comparable to the direct skull measurements using a digital caliper.
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  • 文章类型: Journal Article
    OBJECTIVE: To evaluate the linear and volumetric dimensional changes that occur throughout the fabrication process of monolithic 4.5-6% yttria-stabilized zirconia copings under the influence of different preparation designs and two sintering protocols.
    METHODS: A titanium master die was fabricated using Atlantis core file implant-abutment. Six copings were designed virtually according to different finish line offsets and coping thicknesses, with four equidistant occlusal posts for linear measurements. Zirconia copings were milled using IPS e.max ZirCAD LT zirconia blanks. The experimental groups according to the coping designs were the following: G1: 0.5 mm finish line offset, 0.5 mm thickness; G2: 0.5 mm finish line offset, 1.0 mm thickness; G3: 0.5 mm finish line offset, 1.5 mm thickness; G4: 1.2 mm finish line offset, 0.5 mm thickness; G5: 1.2 mm finish line offset, 1.0 mm thickness; G6: 1.2 mm finish line offset, 1.5 mm thickness. Six samples per group were sintered by standard sintering (SS) and the other six by fast sintering (FS). Linear and volumetric measurements were taken at the three fabrication stages (virtual design, milling stage, and sintering) by using an intraoral scanner and imported as the .stl file to Meshmixer software for analysis. Statistical analysis was performed by a linear mixed effect model via statistical software R (R Core team, 2018).
    RESULTS: There was a significant interaction between the coping design group, stage of fabrication and sintering protocol on the linear (F = 4.451, p < 0.001) and volumetric (F = 2.716; p < 0.001) dimensional changes. Standard sintering G1 showed the smallest linear and dimensional changes among the groups compared to the reference design. Sintered copings had shrunk on average 1.32% within SS and 1.54% within FS linearly and 3.82% within SS and 3.90% within FS volumetrically compared to the initial design parameters.
    CONCLUSIONS: The linear and volumetric dimensional changes did not differ significantly between standard and fast sintering protocols, and the preparation designs had more influence on the dimensional changes compared to sintering protocols.
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