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51.
Extranodal presentation in Hodgkin's disease is uncommon and bone involvement is rare at diagnosis. However, late in the course of this disease, bone involvement may occur in 9% to 35% of the cases. The mandible is very rarely involved even in advanced stages with only seven such cases reported in the literature. Of these only one had primary Hodgkin's disease of the mandible. A second case is described in this report.  相似文献   
52.

Introduction

The aim of this study was to evaluate the radiographic features of permanent three-rooted mandibular first molars with radix entomolaris (RE), investigate the correlation between anatomical classification and radiographic type of RE, and to determine the most effective horizontal beam angulation for the diagnosis of RE.

Methods

Twenty-five extracted mandibular first permanent molars with RE were selected for taking radiographs in 7 horizontal angulations. By using set criteria, 3 evaluators assessed morphologic and radiographic features of the RE and optimum beam angulation for RE diagnosis. Intraexaminer variability was analyzed with Cohen kappa test.

Results

Three types of curvature of RE presented with 3 distinct types of typical radiographic appearance on orthoradial radiographs. We classified the radiographic features of RE into 3 types, as follows: type i, type ii, and type iii. Seven teeth showed type i radiographic features. Zero-degree, 5-degree, 15-degree, and 25-degree radiographs were significantly better than the mesially angulated -15-degree and -25-degree images for detecting the type i RE images (P < .05). Fifteen-degree, 25-degree, and -25-degree horizontal beam angulations showed significantly more accurate diagnoses of RE in 8 type ii images (P < .05). Only 25-degree-angled radiographs were found to have a high diagnostic yield of type iii RE images (P < .05). A significant correlation was found between morphologic and radiographic types of RE (P < .05, contingency coefficient = 0.473). Intraexaminer variability was low, with kappa = 0.68 (P < .05).

Conclusions

RE presents 3 types of typical radiographic features on orthoradial radiographs. Additional 25-degree mesial horizontal-angled radiographs are essential for preoperative identification and evaluation of RE, especially types ii and iii.  相似文献   
53.
Huang M  Meng L  Fan M  Hu P  Bian Z 《Archives of oral biology》2008,53(12):1179-1185

Objectives

To investigate the role of SecA in protein secretion, and to evaluate the effect of biofilm formation on protein secretion in Streptococcus mutans.

Design

S. mutans strains UA159 and GS-5 were used in this study. Cells grown in biofilm and planktonic conditions were observed using immunogold electron microscopy. The mRNA levels of ftf, gtfB, gtfC, gtfD, Pac and secA were analysed in different growth conditions using real-time quantitative polymerase chain reaction. The levels of wall proteins and whole-cell protein extracts were examined using Western blot analysis.

Results

A microdomain colocalised with SecA and virulence factors such as Pac (AgI/II) and glucosyltransferase (GTF) was observed. The mRNA level of secA was upregulated in the biofilm condition. The level of protein expression of SecA and wall protein levels of GTF, fructosyltransferase (FTF) and Pac (AgI/II) in the biofilm condition were significantly higher than in the planktonic condition.

Conclusions

These data suggest that S. mutans utilises the Sec pathway to secrete virulence factor proteins such as Pac (AgI/II), GTF and FTF, and protein secretion occurred at a distinct microdomain. The level of SecA, the key factor in the Sec pathway, was influenced significantly by biofilm formation in S. mutans.  相似文献   
54.
55.
PURPOSE: This study compares measurement of the condylar translation by sonography or axiography in preoperative assessment and follow-up of orthognathic surgery patients. PATIENTS AND METHODS: Forty-seven moderately dysgnathic patients had consecutive examinations by axiography and sonography in a blind fashion at a single time point by 2 observers. Thirty-nine different dysgnathic patients, scheduled for isolated Le Fort I osteotomy, had preoperative condylar translation and 24-month follow-up measured randomized by either axiography (25 patients as control group) or sonography (14 patients as study group). RESULTS: The examination time for axiography was 20 minutes average versus 2 minutes for sonography. The mean differences were 1.7 mm in opening, 2.1 mm in protrusion, and 3.3 mm for mediotrusion. Pearson's proportionality quotient was r = 0.75, analysis of variance (P <.95, F = 3.9, alpha =.05 significance level) was not significant. The 24-month longitudinal follow-up showed a Pearson's proportionality quotient of r = 0.7 between study and control group, and no significant difference in analysis of variance (P <.075, F = 2.81, alpha =.05 significance level). CONCLUSION: Sonography proved adequate for assessment and follow-up of condylar translation compared with axiography in orthognathic surgery patients. Temporomandibular joint sonography was faster and more comfortable, allowed 1-week postoperative examination and reexaminations, and was equally exact. Anatomic details like joint degeneration and disc displacement could be assessed. However, sonography did not measure the inclination of the condylar track.  相似文献   
56.
口腔颌面部肿瘤化疗方案药物敏感性试验   总被引:1,自引:0,他引:1  
尊文以人舌鳞癌细胞系Tca8113为对象,利用MTT法对口腔颌面部肿瘤化疗常用的八种药物和七种方案进行了药敏试验,ADM、5-Fu、CDDP等抗肿瘤作用较强;而PYM、MTX、VCR单用对Tca8113细胞无明显作用。化疗方案中以MMBD、PF、PVP方案为佳,卡铂与顺铂在此疗方案中的作用无明显差异。实验结果提示:肿瘤化疗不能只凭经验用药,应注意化疗的耐药性问题。  相似文献   
57.
58.
A total of 40 patients with 46 fractures of the mandibular condylar process were examined an average of 47 months after the injury. The conventional radiologic examination consisted of panoramic radiography and lateral transcranial view of the fracture in the mouth-open and mouth-closed positions. Sixteen patients with 21 fractures of the condylar process were examined additionally by computed tomography (CT) because of temporomandibular joint problems in the sagittal and coronal projection. Computed tomography revealed bony changes in the fractured mandibular condyle and its position in the mandibular fossa more exactly than conventional radiographic examinations. Furthermore, the results showed that disturbances in the position and function of the articular disc may be more common than was earlier anticipated, suggesting the more frequent use of CT examinations to evaluate temporomandibular joint changes after condylar process fractures.  相似文献   
59.
由于刊名缩写简明,达意,节省籍幅,故而在国内外口腔医学及相关学科专业期刊参考文献中广泛采纳。通常在临床,教学及科研中,因某种目的常需从一篇原始文章或综述的参考文献中查找引用文献,无疑需要具备辨认参考文献中的刊名缩写,理解其全意的能力,  相似文献   
60.
Fatal subarachnoid haemorrhage associated with dental local anaesthesia   总被引:3,自引:0,他引:3  
A case is described of sudden death occurring after the use of a noradrenaline-containing local anaesthetic. Autopsy revealed a massive subarachnoid haemorrhage following a ruptured cerebral aneurysm. The noradrenaline in the local anaesthetic is thought to be an important factor in the cause of the rupture. It is recommended that preparations containing 1:25,000 noradrenaline not be used.  相似文献   
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