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91.
The effects of combined use of earthworm extract(912)and HpD-laser on the produc-tion of reactive oxygen and the biosynthesis of DNA in S_(180) tumor cells were studied throughchemiluminescence measurement and[~3H]-TdR incorporation assay.The results showed that as com-pared with the control,the intensity of chemiluminescence emitted by tumor cells treatedsimultaneously with 912 and HpD-laser was enhanced more than ten-folds,while that treated with912 or HpD-laser alone was increased only 2~4 folds.The[~3H]-TdR incorporation into tumorcells of the former group was inhibited upto 74.1%,and that of the latter groups decreased onlyby 42.2% and 40.0%,respectively.In accordance with these biochemical changes,the ultrastructuraldamage of tumor cells of the former,combinedly treated group appeared to be the most serious.This suggests an additive effect of 912 with HpD-laser on tumor cells.In addition,if free radicalscavengers,such as catalase and superoxide dismutase,were added to the reaction systembefore chemiluminescence assay,the luminescent enhancement effect mentioned above was dramaticallyalleviated,implying the presence of O_2~ and H_2O_2 in the system.Therefore,as to the toxic effecton tumor cells,912 and HpD-laser are not only additive in efficiency,but also similar in theunderlying mechanism of action.  相似文献   
92.
用YAG、CO_2激光按不同功率照射家兔眼,观察对角膜、虹膜、晶状体的损伤和修复过程,探索两种激光对角膜的最小损伤和使其穿孔的有效功率。结果发现:YAG激光用230~250mW(1~2秒)时,可使角膜上皮呈灰白色混浊,1~2W(5~6秒)时角膜穿孔;CO_2激光用340~380mW(0.2~2秒)时,同样使角膜上皮灰白色混浊,1.3~1.4W(1秒)时角膜穿孔,在功率、照射时间、光斑相同的条件下,CO_2激光对角膜损伤重,YAG激光则对虹膜、晶状体损伤重。  相似文献   
93.
本文报道19例外伤或手术后膜性白内障行后房型人工晶体植入联合囊膜切开术或Nd:YAG激光囊膜切开,收到较好的效果,12例视力≥0.3,9例≥0.5。对手术及YAG激光治疗的并发症及预防措施作简要论述。  相似文献   
94.
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   
95.
Erb:YAG and Hol:YAG laser ablation rates of fibrocartilage and nucleus pulposus were measured in vitro simulating clinical conditions. After ablation macroscopic and microscopic appearance of the ablation site was investigated. Hol:YAG and Erb:YAG laser mean ablation rates increased almost linearly with rising energies, showing higher total ablation rates for the Hol:YAG laser due to its higher achievable energy density. At comparable energy densities the Erb:YAG laser appears to be more effective with respect to the corresponding ablation rates. Consequently, the ablational threshold proved to be lower for the Erb:YAG laser. Whereas during Hol:YAG laser ablation, some smoke formation and considerable tissue shrinking occurred, these effects could not be observed during Erb:YAG laser ablation. Consequently macroscopic and microscopic inspection showed some thermal damage after Hol:YAG and only minimal alterations after Erb:YAG laser ablation. Adjacent thermal damage was determined and proved to be lower for the Erb:YAG laser. In our opinion the characteristics of each laser system provide certain advantages for special clinical indications.  相似文献   
96.
Summary To characterize and compare the pathologic, hemodynamic and electrocardiographic changes of both transeatheter laser and electrical energy on ventricle, 33 subendocardial myocardium lesions were induced at energy 60, 120 and 240 Joules by either transcatheter laser irradiation or electrical shock in 7 anesthetized dogs. The following results were observed: 1) Both laser and electrical ablation on myocardium created nonhomogeneous myocardium injury, but laser ablation caused mainly focal tissue vaporization and necrosis, while electrical shock induced widespread tissue degenerations; 2) Both laser and electrical induced-lesion dimensions increased parallel to the total dosage of energy; 3) Laser ablation caused mainly (90%) single ventricular premature beats and 86 % of them occurred within the first minute after energy discharged, while ventricular tachycardias were found in any electrical energy groups; ventricular fibrillations occurring during laser and electrical ablation were 5 % and 13 % respectively (P< 0.01): 4) A decrease in aortic blood pressure and an increase in central verous pressure induced by laser ablation were significantly less than that produced by the same amount of electrical energy (P<0.0l). Our preliminary results have shown that transeatheter laser ablation has great potential for becoming a practical method in the management of refractory tachycardias.  相似文献   
97.
准分子激光原位角膜磨镶术后界面性角膜炎的临床观察   总被引:6,自引:4,他引:2  
目的 :动态观察准分子激光原位角膜磨镶术 (LASIK)后界面性角膜炎 (DLK)的临床变化 ,同时对其角膜瓣下临床特点及处理方法进行分析。 方法 :对 35 0 0例行LASIK后 1 0例 (1 8只眼 )发生DLK患者进行观察。按3、7、1 4天和 1、2、6个月不同时间进行视力、裂隙灯显微镜检查。 结果 :局部用激素、抗生素治疗 1周 ,症状控制 ,1~ 2个月全部吸收。视力恢复至 1 .0~ 1 .5 (1 6只眼 ) ,0 .8~ 1 .0 (2只眼 )。 结论 :LASIK后DLK常发生在术后 1~ 7天内 ,迟发者偶见 ,男性多于女性 ,以局部激素治疗为主 ,严重患者需全身激素加抗生素治疗。DLK早期须与角膜上皮植入、层间感染鉴别  相似文献   
98.
弱激光血疗法的发展及展望   总被引:3,自引:1,他引:2  
本文主要介绍了弱激光血疗的机制及其在我国的发展过程.弱激光血疗法起源于前苏联的紫外光量子疗法,传入我国后经历了静脉内照射疗法,离体血液激光照射回输疗法,口咽部照射伴吸氧疗法,鼻腔内照射疗法等.本文对各种疗法的特点及临床应用进行了详细叙述.有些学者认为,中医的观点也能揭示激光血疗的机制.从中医辨证的角度,人的体质分为虚证和实证.结合中医针灸的虚则补之,实则泻之的原理,根据患者的虚实状况,采用含有中医补泻信息的调制激光照射血液,同时加照相关敏感穴位,促进疗效,以体现中医的辨证施治的原则可取得更好的疗效.  相似文献   
99.
595nm激光对兔耳瘢痕成纤维细胞增殖与凋亡的影响   总被引:2,自引:2,他引:0  
目的:探讨595nmVbeam激光照射对增生性瘢痕动物模型伤口愈合过程中成纤维细胞增殖与凋亡的影响。方法:成年大耳白兔20只,建立兔耳腹侧面增生性瘢痕模型,对比研究在瘢痕形成过程中595nmVbeam激光照射对兔耳瘢痕成纤维细胞的影响,采用免疫组化方法检测增殖细胞核抗原(PCNA)蛋白表达和细胞凋亡的原位检测。结果:兔耳增生性瘢痕经595nmVbeam激光照射后,按不同时间段取材进行免疫组化染色并与对照组比较,高倍镜下观察结果,显示PCNA蛋白表达明显减弱,细胞凋亡增加。结论:595nmVbeam激光照射可抑制兔耳增生性瘢痕成纤维细胞的增殖过程,诱导细胞凋亡。应用595nmVbeam激光预防和治疗瘢痕是可行的。  相似文献   
100.
目的:通过基因微阵列分析,研究经显微切割后的前列腺上皮内瘤变(PIN)的基因表达谱,并将其与前列腺良性增生(BPH)及前列腺癌的mRNA基因表达谱进行对比,探讨前列腺癌的发生、发展,检测PIN及前列腺癌的肿瘤标志物。方法:采用美国Affymetrix公司的HG-U133A基因芯片,检测了16例人的前列腺组织标本,包括5例良性标本,6例PIN以及5例前列腺癌标本,均为新鲜冰冻组织。为了精确获得上皮细胞基因表达谱,避免周围间质细胞及单核细胞的RNA 对结果的影响,我们采用了激光捕获显微切割技术,分别得到了3组纯的上皮细胞群进行研究。结果:有些基因的表达强度在从良性增生到PIN到癌的转化过程中,呈逐渐改变的趋势,但笔者发现3组间基因表达谱存在非常显著的差异。与BPH及前列腺癌相比,PIN有其独特的基因表达谱。结论:基因表达谱中显著上调及下调的特异性基因,可以将PIN 和BPH及前列腺癌中区分开来;基因微阵列分析也有助于揭示代谢通路及信号转导途径的变化,有利于靶基因治疗。  相似文献   
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