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C. Edwin Polk DDS MSD David Buchanan PhD 《American journal of orthodontics and dentofacial orthopedics》2003,124(6):663-669
The cephalometric measurement known as Wits appraisal (AOBO) was studied to determine its importance in diagnosis, treatment, and prediction of treatment success. The Wits appraisal is used primarily to identify unreliable ANB values (those that do not accurately reflect the degree of horizontal jaw discrepancy, ie, those that differ greatly from the AOBO value). Therefore, differences between AOBO and ANB also were evaluated. Because neither measurement alone can assess jaw discrepancies with total accuracy, they were combined, plotted on a scattergram, and divided into equal zones to create a new index of horizontal skeletal discrepancies and treatment predictability. Pretreatment values correspond to treatment difficulty, and posttreatment values correspond to the effectiveness of treatment. Treatment time for each zone also was evaluated. We were able to draw several conclusions from this study. First, combining AOBO and ANB values results in a more accurate measurement of treatment difficulty. These combined values also can be used to predict both treatment time and the success of treatment for horizontal discrepancies. Second, the AOBO value predicts variations in treatment time at each ANB value. Finally, adding ANB and AOBO values and then dividing the total yields zones that represent statistically significant differences in treatment times and percentages of success. The zones also correlate with the difference between AOBO and ANB measurements. 相似文献
124.
成虹 《世界核心医学期刊文摘》2006,2(3):59-62
颈部食管的异位胃黏膜:是否参与了后壁喉炎患咽喉部反流的发病机制;结肠直肠癌手术联合放疗与单纯手术治疗后的大便失禁患,在盆底运动/生物反馈训练的短期和远期疗效方面的比较:一项临床、功能性及内镜/超声内镜检查的前瞻性对照研究。 相似文献
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Hirschsprung disease (HSCR) is a congenital disorder characterized by an absence of ganglion cells in the nerve plexuses of the lower digestive tract. Although mutations in eight different genes (EDNRB, EDN3, ECE1, SOX10, RET, GDNF, NTN, SIP1) have been identified in affected individuals, it is now clear that RET and EDNRB are the primary genes implicated in the etiology of HSCR. All eight genes are involved in the early development of the enteric nervous system, and most act through two distinct biochemical pathways mediated by RET and EDNRB. Mutations in RET and EDNRB account for up to 50% and 5% of HSCR cases in the general population, respectively. Interaction between these two signaling pathways could modify RET expression and, therefore, HSCR phenotype. Here, we report the case of a 1-year-old Taiwanese boy who presented with abdominal distension since birth and bilious vomiting after feeding. HSCR (short-segment type) was diagnosed based on X-ray, lower gastrointestinal series and biopsy findings. Mutation analysis revealed a heterozygous T>C missense mutation in exon 1 of the EDNRB gene, that substitutes the highly conserved cysteine-90 residue in the extracellular domain of the G protein-coupled receptor with an arginine residue (C90R). No RET gene mutation was detected in this patient. 相似文献
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Mandibular prognathism (MP) or skeletal Class III malocclusion with a prognathic mandible is one of the most severe maxillofacial deformities. Facial growth modification can be an effective method of resolving skeletal Class III jaw discrepancies in growing children with dentofacial orthopedic appliances including the chincup, face mask, maxillary protraction combined with chincup traction and the Fr?nkel functional regulator III appliance. Orthognathic surgery in conjunction with orthodontic treatment is required for the correction of adult MP. The two most commonly applied surgical procedures to correct MP are sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy. Both procedures are suitable for patients in whom a desirable occlusal relationship can be obtained with a setback of the mandible, and each has its own advantages and disadvantages. In bilateral SSRO, the intentional ostectomy of the posterior part of the distal segment can offer long-term positioned stability. This may be attributable to reduction of tension in the pterygomasseteric sling that applies force in the posterior mandible. While various environmental factors have been found to contribute to the development of MP, heredity plays a substantial role. The relative contributions of genetic and environmental components in the etiology of MP are unclear. The recent identification of the genetic susceptibilities to MP constitutes the first step toward understanding the molecular pathogenesis of MP. Further studies in molecular biology are needed to identify the gene-environment interactions associated with the phenotypic diversity of MP and the heterogenic developmental mechanisms thought to be responsible for them. 相似文献
130.
The aim of this study was to design a new intravenous blood–gas exchange device and to estimate the design characteristics
of the device with a dimensionless function by using a substance that can be used instead of bovine blood. In addition, the
characteristics of oxygen transfer were estimated using empirical formulas and the reliability of the equations was ascertained
by comparing their output with an experiment performed using bovine blood. The dimensionless function was derived using distilled
water and bovine blood to estimate the oxygen transfer rate. Using the derived equations, the calculated oxygen transfer rates
for bovine blood and distilled water were similar for Reynolds numbers ranging from 0.7 to 7.0. Therefore, it is possible
to estimate the oxygen transfer rate in bovine blood, which is a non-Newtonian fluid, using distilled water, which is a Newtonian
fluid. Moreover, it was possible to verify the related equations because the oxygen transfer rate could be estimated using
the derived equations, according to the diameters of the various device modules. 相似文献