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101.
目的:探讨以赝复体为指导的义耳种植术前设计与修复.方法:采用螺旋CT对1名右侧先天性小耳畸形患者进行颅颌面三维重建,Geomagic软件中行虚拟残耳切除,获得种植导板并确定赝复体的位置.利用导板定位行残耳切除术及种植体植入术,制作卡杆附着体及树脂支架.采用三维光学扫描仪进行面部的三维成像,将CT数据和三维数据拟合,获得最终义耳赝复体的三维模型数据,通过选域激光烧结技术制作义耳蜡型,并翻制成硅胶义耳.结果:最终完成的义耳赝复体与种植修复前的赝复体形态位置完全一致,组织面与缺损区表面完全贴合,其形态、高度与对侧完全一致,患者对颜色、外观非常满意.结论:基于赝复体指导的义耳种植术前设计与修复是一种行之有效的办法和理念,值得在颜面部缺损赝复治疗中推广应用.  相似文献   
102.

Objectives

Successful reconstruction of palatomaxillary defects following cancer ablation represents a formidable challenge for surgeons to achieve consistently favorable outcomes. The purpose of this article is to present our experience in oncologic palatomaxillary repair with temporalis muscle flap (TMF) for medically compromised patients who are not ideal candidates for microvascular reconstruction at a Chinese tertiary referral hospital over a 15-year period (1998–2012).

Method

A retrospective chart review was performed to identify patients with compromised medical conditions who underwent oncologic palatomaxillary reconstruction using TMF. Patients’ demographics, clinicopathological variables, and surgical techniques were presented. Postoperative functional and aesthetic outcomes were assessed by measurements and patients self-evaluations.

Results

Sixty-nine TMFs were successfully harvested and used for immediate oncologic palatomaxillary reconstruction in 67 patients (31 males and 36 females, mean age 60.4 years) with diverse primary malignancies. These patients’ co-morbidities included systemic diseases, preoperative chemotherapy/radiotherapy, and elder over 65 years which precluded the ideal utility of free flaps. Fifty-one patients remained alive without disease, while nine had recurrences/metastases and seven died during the follow-up (0.5–10.4 years, mean 3.7 years). All flaps survived with only partial necroses in four cases. Complications and donor-site morbidities were minimal with five transient facial paralysis and four mild diplopia and enophthalmos. Unrestricted diet and mouth opening, intelligible speech, and satisfactory temporal aesthetics were obtained in most patients.

Conclusion

The TMF is a reliable, versatile, and alternative option for oncologic palatomaxillary reconstruction with satisfactory functional and aesthetic outcomes and minimal complications, especially when appropriately selected for those medically compromised patients.  相似文献   
103.

Objectives

CD4+ CD25+ FoxP3+ T cells (Tregs) play an essential role in sustaining self-tolerance by negatively regulating immune responses. Increased frequencies of Tregs have been reported in a variety of human cancers. The aim of this study was to evaluate the prevalence of Tregs infiltration in the peripheral blood and regional lymph nodes during rat tongue carcinogenesis induced by 4-nitroquinoline-1-oxide (4NQO).

Materials and methods

Forty-eight Sprague–Dawley rats were divided into the control (n?=?16) and experimental groups (n?=?32) to which 4NQO in drinking water was administered. Flow cytometry was used to analyze the prevalence of Tregs in lymphocytes of peripheral blood and regional lymph nodes during 4NQO-induced rat tongue carcinogenesis. CD4+ CD25+ FoxP3+ cells were expressed as a percentage of the total CD4+ cells.

Results

The frequency of Tregs in peripheral blood from squamous cell carcinoma rats was significantly higher than controls (3.82?±?0.62 versus 1.40?±?0.31 %, P?P?Conclusion and clinical relevance Tregs in peripheral blood and lymph nodes were associated with disease progression during 4NQO-induced rat tongue carcinogenesis. This study indicated that the upregulation of Tregs might play important role during oral mucosa malignant transformation.  相似文献   
104.
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   
105.
颌骨结核作为肺外结核的少见病近年呈增多趋势,其发病形式、临床表现也有了较大的变化,容易被误诊为炎症或良恶性肿瘤。本文就近期收治的1例发生于下颌升支骨结核的临床表征、病理表现及相关实验室特点作一阐述,并通过文献复习,分析颌骨结核的临床特征,以期引起重视,提高对疾病的认识。  相似文献   
106.

Objective

To study the effect of Lactobacillus sp. A-2 metabolites on viability of CAL-27 cells and apoptosis in CAL-27 cells.

Methods

Lactobacillus sp. A-2 metabolites 1 and 2 (LM1 and LM2) were obtained by culturing Lactobacillus sp. A-2 in reconstituted whey medium and whey-inulin medium; the cultured CAL-27 cells were treated with different concentrations of LM1 and LM2 (0, 3, 6, 12, 24, 48 mg/mL) and assayed by methyl thiazolyltetrazolium (MTT) method; morphological changes of apoptotic cell were observed under fluorescence microscopy by acridine orange (Ao) fluorescent staining; flow cytometry method (FCM) and agarose gel electrophoresis were used to detect the apoptosis of CAL-27 cells treated LM1 and LM2.

Results

The different concentrations of LM1 and LM2 could restrain the growth of CAL-27 cells, and in a dose-dependent manner; the apoptosis of CAL-27 cells was obviously induced and was time-dependent.

Conclusions

Viability of CAL-27 cells was inhibited by Lactobacillus sp. A-2 metabolites; Lactobacillus sp. A-2 metabolites could induce CAL-27 cells apoptosis; study on the bioactive compounds in the Lactobacillus sp. A-2 metabolites and their molecular mechanism is in progress.  相似文献   
107.
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   
108.
109.
目的研究海口地区少年儿童的骨密度(bone mineral density,BMD)及其影响因素,为了解本地区少年儿童的骨骼发育状况提供参考依据,同时为国家研究此方面的课题提供资料数据对比,对今后研究青少年儿童的骨骼发育情况具有重要的意义。方法对海口市112例少年,年龄12~14岁,其中男生61例,女生51例儿童行问卷调查,并使用双能X线骨密度测定仪检测其左手桡骨远端的BMD。每次测量前进行仪器性能校正检测,并由同一人负责测量。测量对象取坐位,左臂平放,测量其左手桡骨远端1/3BMD,测量时保持标准体位。结果随着年龄的增长,少年儿童的BMD也随之增长;但其运动时间、睡眠时间及营养状况的重视程度却逐年下降。结论运动、睡眠及营养状况是少年儿童骨密度的重要影响因素;应加大对海口地区少年儿童生长发育期提高骨密度的重视度。  相似文献   
110.
表皮生长因子受体(EGFR)是erbB(neu)家族成员之一,与乳腺癌的发生发展密切相关。综述近年来对EGFR的研究进展和它对乳腺癌的预测和预后价值。  相似文献   
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