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41.
笔者用Na3+-YAG激光治疗耳鼻咽喉常见疾病286例,疗效满意。激光手术较常规手术操作简便,术中出血少,反应轻,并发症少,病人痛苦少,值得推广。  相似文献   
42.
43.
Pulsed Nd-YAG laser irradiation of bacteria has been suggested as a possible means of treating contaminated intra-oral sites although relatively few studies have been conducted. In this investigation, the antimicrobial activity of a pulsed Nd-YAG laser was assessed in vitro for a range of oral bacteria using several pulse energies and exposure durations. Pure cultures of each organism were lased in saline suspensions followed by standard colony counting techniques for test and control samples. Microbial inhibition was found to be organism-dependent and varied with energy dose and pulse energy. For all nine test species 120-mJ laser pulses proved more efficient than 80-mJ pulses, with 99.9% kills compared with around 90% kills after exposure to 1800 pulses. These killing activity levels compare favourably with those achieved with other lasers in vitro.  相似文献   
44.
李雪  程立  胡德瑜 《现代预防医学》2006,33(7):1102-1104
目的:定量分析乳牙合面的龋病敏感点位,为指导临床预防和治疗龋病提供依据。方法:采用激光荧光检测仪(DIAGNOdent)检测156名5~6岁儿童共561颗患龋的乳磨牙合面,记录合面龋坏最严重的位点。结果:在上颌第2乳磨牙中,龋坏最严重的位点有60.1%发生在远中窝。在下颌第2乳磨牙中,龋坏最严重的位点有51.2%发生在舌沟;而在下颌第1乳磨牙中,龋坏最严重的位点则易发生在远中窝,占该牙记录位点的34.9%。结论:不同的牙合面患龋严重部位具有统计学规律,提示这些位点是龋坏容易发生和发展的地方,是临床上预防和治疗不可忽略的重要部位。  相似文献   
45.
The human foot is a complex mechanical structure consisting of bones, ligaments and joints. They act together to provide a robust system capable of absorbing and dissipating the intermitted pressure that is subjected to its plantar surface during walking to prevent soft tissue breakdown. Current studies suggest that plantar foot pressure may lead to soft tissue breakdown (e.g. neuropathic ulceration) and hence research has so far concentrated on investigating the mechanical effects of plantar foot pressure on the foot’s integrity. This has been possible through the widely available pressure and force platforms as well as in-shoe pressure systems. However, to understand how plantar foot pressure causes soft tissue breakdown it is vital to investigate both the physiological–mechanical interactions between the skin and plantar foot pressure. This review suggests that with the current advances in technology, the physiological response of skin blood flow to mechanical plantar foot pressure should be investigated and correlated further, both during static and dynamic loading, by developing a new system capable of either measuring both variables simultaneously or by synchronising two systems in real time.  相似文献   
46.
In this study we have investigated the negative influence of CO2 and Nd-YAG laser irradiation on rapid cranial regeneration and whether it has any use in certain types of craniosynostosis. Twenty-two newborn rats were used in the study. Both CO2 and Nd-YAG laser irradiation, which was applied to free bony edges after, suturectomies, resulted in a significant decrease in skull regeneration. Histopathological examinations revealed severe degeneration caused by both types of laser energies.  相似文献   
47.
The Laser Microprobe Mass Analyzer (LAMMA) is a sensitive instrument for identifying and localizing trace elements in tissue samples. Using LAMMA, we have examined melanin-containing neurons of the substantia nigra in patients with Parkinson's disease (PD) and controls. We found that iron significantly accumulates within neuromelanin granules of patients with PD compared to controls. Increased aluminum was found in the neuromelanin granules of 2 of 3 PD cases but in no controls. The accumulation of iron and aluminum, which are known to promote oxidant stress, may account for the selective degeneration of neuromelanin-containing neurons in PD.  相似文献   
48.
The chemical warfare agent, sulphur mustard (SM), is a potent blistering agent in man. Skin exposure can produce partial-thickness burns which take up to three months to heal. The aim of this study was to investigate the use of early laser ablation as a means of accelerating this exceptionally slow rate of healing. Four circular partial-thickness SM burns were induced on the dorsum of nine large white pigs (under general anaesthesia). At 72 h post-exposure, three burns per animal were ablated with a single pass of an UltraPulse 5000C CO(2) laser, at a fluence of 5-6 J cm(-2). All the burns were dressed with silver sulphadiazine and a semi-occlusive dressing. At one, two and three weeks post-surgery three animals were culled and all lesions excised for histological analysis. Burn depth was confirmed and measurements of the radii of regenerative epithelium were performed allowing the area of the zone of re-epithelialisation in each lesion to be calculated. Laser-treated lesions showed a significant increase (350%) in healing rates compared to controls (p<0.005). At two weeks, the laser-treated sites were 95% healed in comparison with control sites (28% healed). These data suggest that laser ablation may be effective in the treatment of partial-thickness SM-induced skin injury.  相似文献   
49.
慢传输型便秘模型的建立及其机制探讨   总被引:13,自引:0,他引:13  
目的 :建立实验型慢传输型便秘模型。 方法 :实验组小鼠皮下注射吗啡建立慢传输型便秘模型 ,记录小鼠粪便重量 ,利用炭沫推进试验比较实验组与对照组小鼠结肠传输功能 ;利用免疫组化技术比较两组小鼠结肠组织中Cajal细胞数量。 结果 :实验组小鼠粪便重量减轻 (P <0 .0 1) ,结肠推进率较对照组明显延长 (P <0 .0 1) ,Ca jal细胞数量较对照组明显减少 (P <0 .0 1)。 结论 :吗啡皮下注射诱导小鼠结肠慢传输型便秘模型符合疾病的基本特点 ,其发病机制可能与内源性阿片肽增多和 (或 )肠道Cajal细胞异常改变有关  相似文献   
50.
光-电一体化技术在美容医学领域的兴起与发展   总被引:9,自引:9,他引:0  
目的介绍光-电一体化技术的机理、适应证的选择、疗效、及并发症和注意事项。方法经文献复习,此项技术的产品有两种类型:①射频与强脉冲光;②射频与激光联合。两种技术发出的能量,分别作用于真皮深层和浅层以及筋膜层,使真皮胶原增厚,以达到皮肤年轻化,并可用于治疗色素沉着、血管病灶、脱毛和痤疮等。电能(RF)40~100J/cm^3,光能15~50J/cm^2。结果根据Fzpatrick皮肤分类和Glogau皱纹分类,选用不同的参数,才能取得好的结果。Bitter和Mulholland报道的Aurora SR设备,皮肤年轻化效果达92%~98%,仅有2%~8%不满意;脱毛效果达80%~85%,20%轻度红斑,24h消失,有8%暂时性色素沉着;下肢静脉扩张最后一次治疗1~6个月,约77%治疗区中有75%~100%扩张血管消失,对桔皮症也取得了较好的效果。结论此项技术的疗效是肯定的,并发症和不良反应少而轻,无不可治愈的不良反应。不同肤色和皱纹选用恰当的治疗参数,是取得满意疗效的保证。  相似文献   
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