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81.
朱国献  徐梁 《中国美容医学》2007,16(11):1511-1512
目的:探求上唇外侧组织瓣在修复较大面积下唇缺损中的作用。方法:根据患者下唇缺损情况,设计上唇外侧组织瓣,旋转后插入缺损组织,同时在缺损吻合处,将上层外侧旋转瓣内侧粘膜肌肉向外牵拉形成部分新的红唇,然后逐层相对缝合,修复缺损。结果:自2003年1月应用此方法修复患者6例,术后随访1~2年,唇部外形好,无流涎,无口闭合不全,效果满意。  相似文献   
82.
目的 通过临床与实验研究选择合适的皮片游离移植手术包扎材料.方法 实验分别以软质聚氨酯泡沫塑料、层叠干纱布、松散干沙团和干棉花团为测试包扎材料.分别在测试包扎材料上加压,记录血浆袋所受到的压力和包扎材料厚度压缩比例的变化;临床常规方法片皮移植,以软质聚氨酯泡沫塑料块加压包扎皮片.结果 软质聚氨酯泡沫塑料当外加压力使其压缩至原厚度的90%~34%时,可使皮片受到25 cmH2O~54.4 cmH2O的压力;此压力范围足以使皮片与创面密切接触,保证皮片成活,又避免过大的压力影响皮片血供重建.以软质聚氨酯泡沫塑料为包扎材料植皮,皮片成活率明显提高.结论 软质聚氨酯泡沫塑料是一种良好的植皮包装材料.  相似文献   
83.
Abstract Background and Aim: The prediction of soft tissue esthetics is important for achieving an optimal esthetic outcome in orthodontic treatment planning. Applicable procedures have so far been restricted to two-dimensional profile predictions that have not proven to be very reliable. The goal of this investigation was therefore to develop a novel finite element-based procedure that allows a three-dimensional, easily visualized, quantitative analysis and prediction of soft tissue behavior for the clinician. The procedure to be developed should be easy to handle and not entail any additional radiation exposure for the patient. Material and Methods: Using a three-dimensional scanner, the facial surfaces of 20 probands were digitalized and individual FEM models were generated. Results: After reduction of data redundancy via several conversion steps, a patient-specific simulation model was prepared consisting of 20,000 to 40,000 individual elements to which specific physical properties could be assigned. The average time required for generating a virtual model was 50 minutes. Problems occurring during model generation were rare (mainly shadowing phenomena and movement artifacts). Conclusion: The procedure outlined herein makes the reliable generation of patient-specific simulation models possible for facial soft tissue prediction in orthodontics.  相似文献   
84.
BACKGROUND: Moderate hypothermia is one of the effective therapeutic methods for head injury in recent years, there are many mechanisms of moderate hypothermia for brain protection, and its influence on cerebral oxygenation is also one of them. OBJECTIVE: To observe the influence of moderate hypothermia on cerebral oxygenation of animals with acute intracranial hypertension, and further investigate the protective mechanism of moderate hypothermia. DESIGN: A randomized controlled trial. SETTING: Department of Neurosurgery, Renji Hospital affiliated to the Medical College of Shanghai Jiao Tong University. MATERIALS: Twenty healthy little pigs, either male or female, weighing 4.5–5.5 kg, were used. Neurotrend-typed multiparameter monitoring system (Diametrics Company, British); CMA/100 micro-injection pump (Carnegie Company, Sweden). METHODS: The experiment was conducted in the Changzheng Hospital affiliated to the Second Military Medical University of Chinese PLA in November, 2001. The pigs were randomized into two groups: the normothermia group (control group, n =10) and moderate hypothermia group (n =10). ① Bilateral femoral arteries were separated, one was connected to pressometer for monitoring mean arterial pressure (MEP), and the other for analysis of blood gases [including peripheral blood pH value, arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of carbon dioxide (PaCO2), HCO3–]. ② Rectal temperature was monitored with mercurial thermometer. ③ Intracranial pressure was monitored using Camino optic ICP probe placed in the subdural space. ④ Neurotrend multiparameter monitoring sensor was inserted into the white matter for about 4 cm to determine cerebral perfusion pressure (CPP, CPP=MAP(ICP), brain tissue partial oxygen pressure (PO2), partial pressure of carbon dioxide (PCO2), HCO3– and brain temperature. The rectal temperature of animals in the moderate hypothermia group was lowered to 34 ℃ using ice bags, and the body temperature was maintained at 33–35 ℃ for 2 hours. The changes of the parameters were observed continuously, and the pigs in the normothermia group were not treated with cooling. MAIN OUTCOME MEASURES: ① MAP, ICP, rectal temperature, CCP; Indexes of cerebral oxygenation detected with Neurotrend-typed multiparameter monitoring system; ② Results of blood gases analysis in the moderate hypothermia group. RESULTS: All the 20 pigs were involved in the analysis of results. ① MAP, ICP, rectal temperature, CCP and indexes of cerebral oxygenation: In the moderate hypothermia group, the ICP after cooling was obviously lower than that before cooling [(3.31±1.19), (5.33±0.95) kPa, P < 0.05], CCP was higher, brain tissue PCO2 [(12.03±1.73), (10.59±2.01) kPa, P < 0.05], and brain tissue pH value was higher [(7.03±1.63), (9.40±1.30) kPa, P < 0.05], whereas the brain temperature was decreased as compared with that before cooling [(34.9±0.3), (37.2±0.2) ℃, P < 0.05]. ② Results of blood gases analysis in the moderate hypothermia group: There were no significant differences in the parameters of peripheral arterial blood gases analysis before and after cooling in the moderate hypothermia group (P > 0.05) CONCLUSION: Moderate hypothermia will not impair the cerebral oxygenation, and it can reduce brain tissue CO2 and decrease brain tissue acidosis.  相似文献   
85.
Introduction Iniencephaly, a neural tube defect involving occiput and inion and combined with rachischisis of the cervical, thoracic spine, and retroflexion position of the head is a very rare congenital abnormality of the fetus–newborn with a 0.1–10 of 10,000 prevalence. This abnormality’s prognosis is thought to be dismal. This abnormality can be associated with other abnormalities such as anencephaly, encephalocele, hydrocephalus, cyclopia, absence of the mandible, cleft lip and palate, cardiovascular disorders, diaphragmatic hernia, renal abnormalities, overgrowth of the arms compared to the legs, and club food and gastrointestinal atresia. Discussion Most of the patients are dead born, and the others die in a few hours. There are only six previously documented long-term survivors. In our case, our patient with iniencephalic signs and findings is still living. She is 2 years old now. We think that this patient presents a mild form of iniencephaly.  相似文献   
86.
面颊部扩张皮瓣的设计和转移   总被引:7,自引:0,他引:7  
目的探讨利用扩张皮瓣修复面颊不同部位皮肤缺损的扩张皮瓣设计。方法269例面颊部血管瘤、瘢痕、色素痣患者,依不同的皮肤缺损位置,在邻近部位放置大小适度的1~3个50~400ml容积的扩张器,扩张充分后采用推进皮瓣法、旋转推进皮瓣法和易位皮瓣法修复。结果269例中共形成305个扩张皮瓣,利用推进皮瓣121个,旋转推进皮瓣145个,易位皮瓣39个;共出现并发症52例,分别为扩张皮瓣远端血运障碍、血肿形成、感染、注水壶渗漏、扩张器外露、睑外翻和包囊挛缩,这些并发症基本未影响最终的手术效果,术后面颊部形态正常。结论我们提出的扩张皮瓣的设计和转移原则,对于面颊部的皮肤缺损组织扩张术治疗有非常重要的参考价值。  相似文献   
87.
封闭式负压引流治疗软组织感染   总被引:3,自引:0,他引:3  
目的探讨封闭式负压引流治疗软组织感染的疗效。方法应用封闭式负压引流治疗开放性骨折发生软组织感染18例。结果18例均获随访,时间6个月-1年6个月。软组织感染均愈合,骨折正常愈合12例,延迟愈合6例,无慢性骨感染发生。结论封闭式负压引流治疗软组织感染,可短期控制感染,为进一步治疗创造条件,尤其适用于深部软组织感染患者。手术简单,疗效可靠,适合基层医院应用。  相似文献   
88.
包含颈外静脉的颈阔肌肌皮瓣修复口腔癌切除后缺损   总被引:1,自引:0,他引:1  
目的探讨将颈外静脉包含在颈阔肌肌皮瓣内修复口腔癌切除后缺损的手术方法。方法先形成蒂在颌缘下包含颈外静脉的颈阔肌肌皮瓣,待口腔肿瘤切除后,将肌皮瓣经口底隧道引入口腔修复缺损。结果临床应用17例,肌皮瓣均无血运障碍,100%存活,其中有2例发生口面痿,经换药后痿口完全闭合。结论将颈外静脉包含在颈阔肌肌皮瓣内有助于肌皮瓣血循环的改善和存活率的提高。  相似文献   
89.
目的应用重组人骨形态发生蛋白4基因腺相关病毒载体(AAV-hBMP4)转染兔骨髓基质干细胞(BMSCs),观察其对BMSCs生物学行为的影响,从而为骨组织工程寻找理想的病毒载体及种子细胞。方法全骨髓法培养兔BMSCs,按感染复数(MOI)值不同设定为四组,分别转染兔BMSCs,观察病毒量对细胞形态的影响。选取影响最小的MOI值,进行后续实验。转染兔BMSCs,MTT法描记细胞生长曲线,观察AAV对细胞增殖活性的影响。以重组增强型绿色荧光蛋白基因的腺相关病毒载体(AAV-EGFP)为参照,行流式细胞仪检测,计算转染效率。AAV-hBMP4与对照病毒AAV-EGFP分别转染细胞,观察细胞形态,行碱性磷酸酶(ALP)染色、Von Kossa染色及ALP含量测定,观察成骨活性。兔肌袋实验观察异位成骨情况。结果MOI值为5×10~4 vg/cell时,AAV对细胞形态影响最小,以此值进行后续实验。AAV转染后,细胞增殖活性良好,转染效率为55%~65%。AAV-hBMP4转染后,细胞形态呈现典型的成骨改变,ALP染色及Von Kossa染色均出现成骨的特征性改变,而AAV-EGFP组无上述改变。细胞上清ALP含量测定显示,实验组ALP含量显著增高,与对照组比较差异有统计学意义(t=218.65,P<0.01)。兔肌袋实验术后4周组织学检测可见大量钙盐沉积,矿化结节形成。结论AAV-hBMP4转染效率高,对BMSCs的增殖活性影响小,AAV-hBMP4转染的BMSCs可望成为组织工程化骨的理想种子细胞。  相似文献   
90.
Mesenchymal stem cells (MSC), easily culture-expanded from bone marrow, can significantly enhance bone defect healing. Several proteins, such as the bone morphogenetic proteins (BMPs) and in particular BMP-7, are involved in bone formation in vitro and in vivo. In this preclinical study, we evaluated if the association of human MSC (hMSC) with BMP-7 had synergic action on bone healing. Rat femoral defects (n=12) were treated with: autoclaved bone and mononucleated cells (MNC) as control group G1; bone and hMSC, group G2; bone with BMP-7, group G3; bone and hMSC plus BMP-7, group G4. Defect regeneration was evaluated with plain radiographs after 2, 4, 8 and 12 weeks and with histological analysis. We observed organized trabeculae bridging between the osteotomic ends of the host bone in rats treated with the association of hMSC and rhBMP-7. These trabeculae, formed by a core of devitalized tissue surrounded by osteoblasts, osteocytes and osteoclasts, were continuous with a cortical-like structure of bony tissue. Such new bone formation of the group treated with the association of hMSC and rhBMP-7 (G4) was clearly superior compared to rats treated with rhBMP-7 (G2) or hMSC (G3) alone, as shown by radiographic analysis and histological study. The present study suggests that the association of hMSC and BMP-7 is more effective than hMSC or BMP-7 alone in the healing of femoral defects in rats. Further studies with larger samples are required to confirm these results and to evaluate the best dosage.  相似文献   
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