【作者】 李成；

【导师】 李迎新；

【作者基本信息】 天津医科大学 ， 生物医学工程， 2008， 硕士

【摘要】 创伤是造成人类残疾和死亡的主要原因之一。特别是某些难愈性创伤,如重度烧伤、褥疮等,经常是久治不愈,给病人造成极大的痛苦。全球每年因创伤致死者数百万人,人们一直在寻找能够促进创伤快速无疤痕愈合的治疗方法。基于弱激光生物刺激效应的弱激光创伤疗法以其操作简单,痛苦小,毒副作用低,不接触创面等特点,而成为创伤治疗的新的希望。在对弱激光治疗创伤的四十几年研究中,研究人员对不同波长激光,不同剂量下弱激光对创伤治疗的效果做了大量研究,实验结果不一。为验证和探讨不同波长弱激光在创伤修复中的作用,将32只创伤模型Wistar大鼠随机分为A、B、C、D四组:A组为创伤模型无照射组,B组为630nm红光照射组,C组为808nm近红外光照射组,D组为630nm与808nm激光联合照射组。自创伤模型制备起,使用5mW/cm~2 630nm和10mW/cm~2 808nm弱激光分别照射不同组,每天照射一次,每次10分钟,7次为一个疗程,本实验治疗两个疗程,中间休息2天。每两天测量记录创面面积,并于第3天、第7天和第14天活体取组织制成切片,通过HE染色观察创伤愈合进程中的病理变化;通过免疫组化方法检测创伤组织中TGF-β1的表达情况。在上述剂量下,B组、D组与A组之间具有统计学意义(p＜0.05),表明630nm红光照射和630nm与808nm激光联合照射都能够加速大鼠创面收缩;B组和D组之间的差异无统计学意义(p＞0.05),表明630nm红光照射和630nm红光与808nm近红外光联合照射这两种方法的疗效相当;C组与A组之间无统计学意义(p＞0.05),表明在上述剂量下单独808nm近红外光照射不能加速大鼠创面收缩。结果还显示,不同时间点TGF-β1表达面积差别有统计学意义(p＜0.05),各组TGF-β1表达面积都是随时间先增强再减弱的一个过程;不同波长弱激光对TGF-β1在创伤组织中的表达面积差别没有统计学意义(p＞0.05)。本课题证实了630nm红光照射和630nm红光与808nm近红外光联合照射具有明显的促进创伤愈合作用,两种照射方法的疗效相当;808nm弱激光单独照射并没有观察到对创伤愈合的促进作用。TGF-β1在创伤愈合过程中的表达,是一个先增强后减弱的过程,在炎性渗出物、炎细胞(巨噬细胞等)、成纤维细胞、毛细血管内皮细胞和上皮细胞胞浆中均有阳性表达。本研究并没有观察到弱激光对其表达有明显的影响作用。基于上述实验结果,从整机设计、驱动电路设计到加工制作,再到调试试验,对630nm/808nm双波长半导体激光治疗机样机的关键技术进行了研究,可满足进一步实验研究和双波长弱激光创伤疗法在临床推广的需要。更多还原

【Abstract】 The wound has been one of the main causes of human disability and death, especially some chronic ones which always last for a long term, such as severe burn, bedsore, etc. It brings great suffering to the patients and causes millions of people dead each year in the world. People are still looking for new treatments that can speed up wound healing with less scars left.Low level laser therapy (LLLT) has been the new hope for wound healing because of its characteristics which are easy operation, painless, low toxicity, no contact with the wound surface, etc. During more than forty years’ LLLT study for wound healing, the researchers had done a lot of experiments with different wavelengths and dosages. The results were inconsistent.To verify and explore the effect of different wavelengths of low level laser for wound healing, 32 wound model Wistar rats were randomly divided into A, B, C and D Group. Group A received no laser treatment. Group B received 5mW/cm~2 630nm red laser treatment. Group C received 10mW/cm~2 808nm IR laser treatment. Group B received a combination of both 5mW/cm~2 630nm red laser and 10mW/cm~2 808nm IR laser treatment. After the wound model caused, the treatment groups were exposed to laser irradiation for 10 minutes once a day. The treatment lasted for 14 days with 2 days rest after a 6 days’ constantly irradiation. The wound area was recorded every two days. The pathologic changes of wound tissue were observed by HE staining section. The expression of TGF-β1 in the wound tissue was determined by the immuneohistochemical techniques. Statistical analysis revealed that both of the 630nm red laser treatment and the combination of both 630nm red laser and 808nm IR laser treatment could speed up wound shrinkage (p <0.05). But the 808nm IR laser treatment could not speed up wound shrinkage (p >0.05). The curative effect for wound healing was no statistical significance between the 630nm red laser treatment and the combination of both 630nm red laser and 808nm IR laser treatment (p >0.05). The change of expression area of TGF-β1 was statistical significance on different date (p <0.05). It increased firstly and then reduced. The effect of low level laser of different wavelengths for the TGF-β1 expression in wound tissue was not observed (p>0.05).This study proved that the 630nm red laser treatment and the combination of both 630nm red laser and 808nm IR laser treatment both could speed up wound healing obviously, and the curative effect is equivalence. The 808nm IR laser treatment could not speed up wound healing. TGF-β1 was expressed in the inflammatory exudation, the inflammatory cells, the fibroblast, the endodermis cells of capillary vessel, and the epithelia, etc. The expression increased firstly and then reduced. The effect of low level laser for the expression of TGF-β1 was not observed. Based on the experiment, this thesis studied the key technologies of the 630nm/808nm double-wavelength semiconductor laser instrument for the further research and clinical development.更多还原