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61.
M Buchelt H P Kutschera T Katterschafka H Kiss B Schneider R Ullrich 《Lasers in surgery and medicine》1992,12(4):375-381
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
62.
采用双波长薄层扫描法测定新疆雪莲芦丁含量。以乙酸乙酯一甲酸一水(67:13:20)为展开剂,硅胶GF254薄层析分离;测定波长λs为263nm,参比波长λR为235nm。样品回收率为97.3%;相对标准偏差为2.8%。在芦T0.5~6.0μg范围内有良好的线性,相关系数为0.999。本法简便、快速、灵敏度高。 相似文献
63.
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
64.
65.
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
66.
大鼠肺微血管和肺泡铸型的扫描电镜观察 总被引:2,自引:0,他引:2
用扫描电镜观察以甲基丙烯酸甲酯灌注鼠的肺微血管和肺泡。胸膜下毛细血管较稀疏,网孔粗大。毛细血管部分成锐角折返,亦可见毛细血管盲端。肺泡隔毛细血管均成扁平状膨大,且相互吻合成单层密集网。肺泡铸型为大小不等、不规则的多面体,表面可见肺泡Ⅱ型细胞核之压迹。两肺泡之间可见呈桥式连接的肺泡孔,亦可见部分呈三通管样相连。 相似文献
67.
Tobias Forschner Stefan Buchholtz Eggert Stockfleth 《Journal der Deutschen Dermatologischen Gesellschaft》2007,5(6):467-475
Vitiligo is a skin disease with a worldwide prevalence ranging from 0.5% to 4%. Conservative therapies include photochemotherapy, phototherapy with UVB radiation (broadband UVB 290–320 nm, narrow band UVB 311 nm), systemic steroids and pseudocatalase. Modern therapeutic options include treatment with topical immunomodulators (tacrolimus, pimecrolimus), analogues of vitamin D3, excimer laser and surgery/transplantation. Our analysis compares these therapies for vitiligo and the evidence levels supporting their effectiveness. Conclusions: The face and neck respond best to all therapeutic approaches, while the acral areas are least responsive. For generalized vitiligo, phototherapy with UVB radiation is most effective with the fewest side effects; PUVA is the second best choice.Topical corticosteroids are the preferred drugs for localized vitiligo. They may be replaced by topical immunomodulators which display comparable effectiveness and fewer side effects.The effectiveness of vitamin D analogues is controversial with limited data. Surgical therapy can be very successful, but requires an experienced surgeon and is very demanding of time and facilities, thus limiting its widespread use. L-phenylalanine therapy appears effective on the face but enjoys neither widespread use nor extensive data support. No single therapy for vitiligo can be regarded as the most effective as the success of each treatment modality depends on the type and location of vitiligo. 相似文献
68.
CO2激光治疗宫颈糜烂2412例疗效观察 总被引:2,自引:0,他引:2
李杰 《中华中西医学杂志》2005,3(10):2-4
目的 探讨CO2激光治疗宫颈糜烂的疗效。方法 采用CO2激光输出功率20-40w,波长10.6μm,针对轻、中、重不同糜烂程度采用不同光束强度,光斑直径约0.3-0.5的连续波治疗宫颈糜烂2412例。结果 术后三个月复查,总有效率100%。结论 CO2激光治疗术简单、安全、疗效满意,适用于治疗I-Ⅲ0宫颈糜烂。 相似文献
69.
The aim of this study was to evaluate corneal innervation in soft contact lens wearers using the Tomey Confoscan confocal microscope (40x/0.75 objective lens). Three distinct age- and sex-matched subject groups were involved, including extended soft (hydrogel and silicone-hydrogel) contact lens wearers, overnight soft (hydrogel) contact lens wearers, and non contact lens wearers. A number of variables were objectively measured, subjectively evaluated, or graded in order to investigate the distribution and morphology of corneal nerves. For most of the evaluated parameters, no statistically significant differences were found. However, qualitative observations showed noticeable differences in corneal nerve appearance among the different subject groups; the degree of corneal oedema was suggested as the main causative factor. In conclusion, neither the short-term (overnight wear) nor the long-term (12-month extended wear) soft contact lens wear appeared to affect the morphology and/or distribution of corneal nerves as viewed with confocal microscopy. 相似文献
70.
Kenji Yamao Atsushi Irisawa Hiroyuki Inoue Koji Matsuda Mitsuhiro Kida Shomei Ryozawa Yoshiki Hirooka Teruo Kozu 《Digestive endoscopy》2007,19(Z1):S180-S205
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented. 相似文献