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111.
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The aim of this study was to apply biomechanical analysis model to evaluate the effects of bioabsorbable internal fixation devices on maxillary Lefort Ι fracture. CT scan technology and the finite element software (ansys ) were used to establish three‐dimensional finite element models of five resorbable internal fixation devices in maxillary Lefort Ι fractures. We used the model to calculate the stress of the upper jaw and internal fixation. We further analyzed the stability of fixation under four occlusions. The fixation using two bioabsorbable plates was not stable. The zygomaticomaxillary pillars fixation is more stable than other fixations. The stability of fracture fixation was influenced with the molar occlusion. The current study developed a functional three‐dimensional finite element model of bioabsorbable internal fixation and compared the stability of five fixation methods for maxillary Lefort Ι fractures. The results would facilitate the application of bioabsorbable materials in dental clinic.  相似文献   
113.
Objectives: Mandibular resection for oral cancer is often necessary to achieve an adequate margin of tumor clearance. Mandibular resection has been associated with a poor health-related quality of life (HRQOL), particularly before free fibula flap to reconstruct the defect. The aim of this study was to evaluate health-related quality of life in patients who have had mandibular resections of oral cancer and reconstruction with free fibula flap. Study Designs: There were 115 consecutive patients between 2008 and 2011 who were treated by primary surgery for oral squamous cell carcinoma, 34 patients had a mandibular resection. HRQOL was assessed by means of the 14-item Oral Health Impact Profile (OHIP-14) and University of Washington Quality of Life (UW-QOL) questionnaires after 12 months postoperatively. Results: In the UW-QOL the best-scoring domain was mood, whereas the lowest scores were for chewing and saliva. In the OHIP-14 the lowest-scoring domain was social disability, followed by handicap, and psychological disability. Conclusions: Mandible reconstruction with free fibula flap would have significantly influenced on patients’quality of life and oral functions. The socio-cultural data show a fairly low level of education for the majority of patients. Key words:Health-related quality of life, free fibula flap, mandibulectomy, UW-QOL, OHIP-14.  相似文献   
114.

Purpose

The use of three-dimensional (3D) photography for anthropometric measurements is of increasing interest, especially in the cranio-maxillofacial field. Before standard implementation, accurate determination of the precision and accuracy of each system is mandatory.

Methods

A mannequin head was labelled with 52 landmarks, and 28 three-dimensional images were taken using a commercially available five-pod 3D photosystem (3D VECTRA; Canfield, Fairfield, NJ) in different head positions. Distances between the landmarks were measured manually using a conventional calliper and compared with the digitally calculated distances acquired from labelling by two independent observers. The experimental set-up accounted for clinical circumstances by varying the positioning (vertical, horizontal, sagittal) of the phantom.

Results

In the entire calliper measurement data set (n?=?410), a significant difference (p?=?0.02) between the directly measured and corresponding virtually calculated distances was found. The mean aberration between both modalities covering all data was 7.96 mm. No differences (p?=?0.94) between the two groups were found using a cut-off of 10 % (leaving n?=?369 distances) due to considerable errors in direct measurements and the necessary manual data translation. The mean diversity of both measurement modalities after cut-off was 1.33 mm (maximum, 6.70 mm). Inter-observer analysis of all 1,326 distances showed no difference (p?=?0.99; maximal difference, 0.58 mm) in the digital measurements.

Conclusion

The precision and accuracy of this five-pod 3D photosystem suggests its suitability for clinical applications, particularly anthropometric studies. Three-hundred-and-sixty degree surface-contour mapping of the craniofacial region within milliseconds is particularly useful in paediatric patients. Proper patient positioning is essential for high-quality imaging.  相似文献   
115.
目的 :探讨肺癌组织层黏连蛋白 (LN)及其受体 (LN -R)的表达和肿瘤转移及预后关系。方法 :采用免疫组织化学技术在 4 2例肺癌患者中研究LN和LN -R的表达。结果 :Ⅰ期患者LN(5 8.30 % )表达高于Ⅱ期 (14 .30 % )及Ⅲ~Ⅳ期 (37.5 2 % )患者 ;无淋巴结肺癌转移患者LN表达率 (6 6 .6 6 % )明显高于有淋巴结转移患者 (2 4 .2 0 % )。有淋巴结肺癌转移患者LN -R表达率 (84 .80 % )明显高于无淋巴结转移患者 (2 2 .2 2 % ) ,这些差异均有统计学意义 (P <0 .0 1)。结论 :LN及其受体 (LN -R)表达在肺癌组织的恶性生物学行为相关 ,可能是临床治疗和预后估计的有用指标。  相似文献   
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118.
Cutaneous histoplasmosis is a rare entity, although it can be seen in a substantial portion of renal transplant recipients with disseminated disease. The prognosis of disseminated disease is worse than isolated cutaneous involvement, and significant delays in diagnosis are reported. We reviewed reports of cutaneous histoplasmosis with and without dissemination in the setting of renal transplantation to examine incidence, timing of diagnosis, clinical features, and prognosis. Remarkable morphologic variability and the non‐specific appearance of skin findings suggest that tissue culture is required for definitive diagnosis. Cutaneous lesions represent an easily accessible source for early diagnosis.  相似文献   
119.
120.

Background

Gastric submucosal tumors are often treated by laparoscopic wedge resection. This study aimed to examine the feasibility of gastric full-thickness resection through a totally endoscopic approach using the master and slave transluminal endoscopic robot (MASTER), and closure of the luminal defect with an endoscopic suturing device.

Methods

The operation was performed in two live porcine models under general anesthesia. First, the anterior wall of the stomach was slung to the abdominal wall using a percutaneous suturing device. An imaginary 5-cm lesion was marked using a needle knife. After the initial mucosal incision was made using an IT knife, the MASTER was introduced through a long overtube. A circumferential mucosal incision was completed with the MASTER to expose the muscularis propria which was grasped and incised to the serosal layer by electrocautery applied through the hook of the MASTER. The full-thickness resection of the gastric wall was completed with retraction using the grasper and dissection using the hook. While the defect was being created, the luminal space was maintained with traction of the percutaneous sutures. The defect was closed with suture plication using an Apollo Overstitch device.

Results

Two full-thickness gastric resections were performed in two nonsurvival porcine models (body weight = 30 and 35 kg, respectively) using the MASTER. The total procedure time was 56 min for the first model and 70 min for the second model. The luminal view was maintained during the whole procedure, and there was no damage to surrounding organs throughout the whole procedure. The gastric defects were closed successfully using Overstitch, with satisfactory gastric distension and no gas leakage afterward.

Conclusion

The current experiment demonstrated the feasibility and safety of a totally endoscopic approach for the treatment of gastric submucosal tumors: full-thickness resection with the MASTER and successful closure of the defect using Overstitch.  相似文献   
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