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排序方式: 共有1727条查询结果,搜索用时 31 毫秒
1.
《Revista brasileira de otorrinolaringologia (English ed.)》2022,88(5):663-668
IntroductionThe impact of the nasal septum morphology on the severity of obstruction symptoms has not been fully explored.ObjectiveThis study aimed to investigate whether the morphology of the deviated nasal septum assessed by computed tomography may explain nasal obstruction severity.MethodsThe study included 386 patients who were referred to the computed tomography examination of the paranasal sinuses. Patient selection criteria were the absence of facial anomalies, facial trauma, nasal surgery, and sinonasal tumors. Computed tomography images were used to estimate deviated nasal septum prevalence, the prevalence of Mladina's seven types of deviated nasal septum, and to measure the deviated nasal septum angle. Nasal obstruction severity was assessed by the nasal obstruction symptom evaluation, NOSE scale. The relationship between NOSE score, deviated nasal septum morphology, and deviated nasal septum angle was performed by a statistical regression model on the reduced sample of 225 patients.ResultsThe prevalence of deviated nasal septum was 92.7%. Type 7 deviated nasal septum was the most frequent (34.2%) followed by type 5 (26.2%) and type 3 (23.6%). The worst NOSE scores were recorded in the type 2 deviated nasal septum (45.00 ± 28.28). The mean deviated nasal septum angle in patients with nasal obstruction was 8.5° ± 3.24. NOSE scores were not significantly associated with deviated nasal septum types and angles.ConclusionPatients with different types of deviated nasal septum have different NOSE scores. Computed tomography morphology of the deviated nasal septum could not fully explain the severity of nasal obstruction. 相似文献
2.
《Gait & posture》2022
BackgroundMedical and surgical interventions to prevent or reduce bone deformities and improve gait in children with cerebral palsy (CP) are based on empirical evidence that there is a relationship between bone deformities and gait deviations.Research questionWhat is the relationship between tibial-femoral bone morphology and kinematic gait variables in ambulant children with CP?MethodsA retrospective analysis was conducted on data from 121 children with uni- (n = 64, mean age 9.9 (SD 3.4) years) and bi- lateral (n = 57, mean age 10.4 (SD 3.6) years) CP who had undergone 3D gait analysis and biplanar X-rays (EOS® system). The limbs were split as DIP (the more impaired limb of children with bilateral CP), HEMI (the impaired limb of unilateral CP) and REF (the unimpaired limb of unilateral CP). Multi-variable Linear Regressions were performed between 23 kinematic variables, the Gait Deviation Index (GDI) and a model composed of nine 3D bone variables for each limb type.ResultsWhen the whole sample was pooled, 72% of R2 values were poor, 16% were fair, and 12% were moderate. Lower limb bone morphology models explained less than 1% of GDI variability. Correlations between tibial-femoral rotational parameters and hip rotation were mostly poor. Mean foot progression angle was the only kinematic parameter that was fairly to moderately correlated with bone variables in the 3 limb types. A tibial-femoral bone model explained 48% of the variability of mean foot progression angle in the REF limbs, 31% in the HEMI limbs and 25% in the DIP limbs.SignificanceTibial-femoral bone morphology was only weakly related to kinematic gait variables, in contrast with common clinical assumptions. These results suggest that factors other than bone morphology influence gait quality and thus a thorough clinical examination and gait analysis is required prior to making treatment decisions. 相似文献
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《The Knee》2021
BackgroundMedial meniscus (MM) translates and extrudes posteriorly during knee flexion in MM posterior root tear (MMPRT) knees, and transtibial pullout repair of MMPRT has been performed to regulate the MM extrusion. This study aimed to calculate each suture translation during knee flexion in transtibial pullout repair of MMPRT, and to investigate the morphologic features of the MM that lead to longer suture translations during knee flexion.MethodsThirty patients with MMPRT who met the operative indication of pullout repair were enrolled and investigated prospectively. Pullout repair was performed by using two simple stitches (outer and inner sutures) and an all-inside suture in the posteromedial part of the MM. Each suture’s translation from 0° to 90° of knee flexion was measured intraoperatively. The MM morphologic features, including MM medial extrusion (MMME) and MM posterior height (MMPH), were measured using preoperative magnetic resonance imaging, and the correlation between these values and each suture translation was evaluated.ResultsThe average outer, inner, and all-inside suture translations were 4.8 mm, 3.9 mm, and 1.3 mm, respectively. Significant correlations were observed between the outer suture translation and MMME, and MMPH (p < 0.001 and <0.01, respectively). The thresholds for preoperative MMME and MMPH for longer outer suture translations (≥6 mm) were 2.1 mm and 5.4 mm, respectively.ConclusionsPreoperative longer MMME and higher MMPH were associated with longer meniscus translations during knee flexion during MMPRT repair. 相似文献
6.
《The Knee》2021
BackgroundWhether the distal femur and the proximal tibia have narrower aspect ratios in smaller knees has not been clarified. The purpose of this study was to confirm the dimensional characteristics of the distal femur and the proximal tibia using a novel method for consistently determining knee size.MethodsA total of 220 Japanese osteoarthritic knees (160 female and 60 male knees) were analyzed using computed tomography. The mediolateral (ML) and the anteroposterior (AP) dimensions of the distal femur (fML, fAP) and the proximal tibia (tML, tAP) were measured. The aspect ratios (ML/AP) of the distal femur (fML/fAP) and the proximal tibia (tML/tAP) were assessed against the product of AP × ML as a consistent determination of knee size.ResultsThe fML/fAP ratios positively correlated with knee size (fAP × fML) (r = 0.420, p < 0.001), only in the combined cohort, attributable to the narrower aspect ratios of female knees. No correlations were found between the tML/tAP ratios and knee size (tAP × tML) among females, males, nor all subjects (p = 0.299, 0.994, and 0.996, respectively). Aspect ratio correlations to knee size diverged between the three knee size indices, AP, ML, and AP × ML.ConclusionsAP × ML was the meaningful option for knee size indexing in our morphological analyses. The distal femur, but not the proximal tibia, was found to have a narrower aspect ratio in female knees in the Japanese population. 相似文献
7.
Fatalities attributed to powered circular saws appear to be vanishingly rare events with highly wounding and rapidly incapacitating effects. When they do occur, they are mainly self-inflicted in nature. We report the suicide committed by a 79-year-old man using a self-made circular table saw. Autopsy confirmed that the man received multiple heterogeneously distributed saw-type impacts to the head and neck resulting in complete amputation of the upper skull and partial beheading. Homemade or modified commercial sawing instruments and the resultant injuries pose a number of forensic challenges starting from the death scene investigation, continuing with technical examinations, and concluding with determining the manner of death. As with all deaths due to sharp force injuries, fatalities involving power tools such as chainsaws, circular, and band saws warrant a high degree of suspicion of criminal activity and require diligence during all phases of the death investigation. 相似文献
8.
《Surgical pathology clinics》2014,7(4):543-557
Seventy percent of parasympathetic paragangliomas arise in the head and neck and are nonsecretory. Awareness of the differential diagnosis based on location, overlapping morphology, and immunohistochemical profiles aids in the correct diagnosis, particularly on limited tissue samples. Moreover, 30% to 40% of head and neck paragangliomas are known to be associated with hereditary syndromes, with the succinate dehydrogenase enzyme family comprising the most frequent association. The pathologist’s role is becoming increasing critical for facilitating optimal patient care beyond the initial tissue diagnosis of paraganglioma to include screening and documenting potential hereditary tumors requiring further patient counseling and testing. 相似文献
9.
目的:研究熔附温度和熔附时间对多微孔纳米二氧化硅粒子(SP1 SiO2)表面结构及形态的影响。方法:将SP1SiO2以250℃/h的升温速度分别升至500、650、800、950、1100℃,并分别保持10、30min和3h制作试样,进行表面结构及形态测试。结果:随烧结温度的增高和时间的延长,SP1 SiO2颗粒表面的Si-OH键特征峰值逐渐减弱,条件为950℃、10min和30min,650℃、3h时完全消失;随着熔附温度的升高和熔附时间的延长颗粒增大、粒度分布变窄。结论:熔附温度和熔附时间影响SP1 SiO2颗粒表面的Si-OH含量和颗粒大小、粒度分布。 相似文献
10.
先天缺牙与牙形态、大小异常相互关系的研究 总被引:6,自引:0,他引:6
目的 探讨先天缺牙与牙形态异常及牙大小异常的相互关系。方法 对79例先天缺牙患者的缺牙部位、缺牙数目,余留牙异常的牙体形态进行分析。并按缺牙程度及部位分成4组,测量其牙冠宽度。结果 (1)上颌侧切牙、下颌中切牙为临床最常见牙先天缺失部位,上颌中切牙,上下颌第一磨牙为牙列中最不易先天缺失的牙齿,但上颌中切牙在先天缺牙患者中常呈轻度的锥形牙冠。(2)先天缺牙常伴牙齿形态异常,以上颌侧切牙,下颌尖牙、上颌第二前磨牙,上下颌第二磨牙多见。(3)轻度先天缺牙患者余留牙大小无异常,随着先天缺牙严重程度增加,前牙有逐渐减小趋势而后牙大小较稳定。结论 (1)上颌侧切牙为牙列中最不稳定的牙齿:(2)牙齿形态、大小、数目异常可能是一个连续的变异过程,可能为同一机制的不同表现。 相似文献