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1.
QS激光治疗面部雀斑临床疗效观察   总被引:2,自引:0,他引:2  
用QSND YAG倍频532nm及QS翠绿宝石755nm波长激光一次治疗面部雀斑。研究:观察哪些波长组合及用何方法在临床应用既能达到美容效果、又能缩短疗程、节约费用。在将近选患者面部色素密度均匀部位分左、中、右区域进行治疗观察后,发现:(1)QS532nm治疗组6个月疗效达40.5%(P〈0.05),(2)QS755nm治疗组6个月疗效达12%(P〈0.05),(3)QS532nm+QS75nm治疗组疗效达72%(P〈0.01)。说明采用两种波长激光同时复合治疗疗效好,而且起到了美容效果,临床值得推广。  相似文献   

2.
倍频Nd:YAG激光对钝项螺旋藻的诱变效应   总被引:3,自引:0,他引:3  
利用倍频Nd:YAG激光(波长532nm,功率500mW,功率密度160mW/cm^2)诱变钝项螺旋藻,辐照时间为15min、10min、5min通过测定藻丝形态参数、叶绿素α、β-胡萝卜素、生长速度,比较倍频Nd:YAG激光对钝项螺旋藻生长的影响。实验结果表明:与出发株相比,经倍频Nd:YAG激光辐照后,藻丝形态发生变化,藻丝长、螺旋数、螺旋长变小;15min,10min辐照组出现螺旋变松驰;1  相似文献   

3.
不同波长激光辐照花生种子的生物学效应   总被引:9,自引:0,他引:9  
本实验考察了K+r、Ar+、Nd:YAG、HeNe和LD等不同波长的激光辐照对花生种子产生的生物学效应。结果显示,适当剂量不同波长的激光辐照都能促进花生种子生长。在辐照剂量为0.128w/cm2×180s的条件下,较短波长激光对花生幼苗的促进作用比长波长激光显著;在辐照剂量为1.28w/cm2×18s的条件下,短波长激光对花生种子的萌发及胚的生长有抑制作用,而长波长激光有促进效应。在相同辐照剂量条件下,不同功率密度与时间的组合其辐照效果不同。1.28w/cm2功率密度的Nd:YAG(532nm)激光脉冲输出辐照对花生种子的生长产生显著的抑制作用。实验结果提示,要得到相同的辐照效果,长波长激光与短波长激光相比,必须提高辐照功率密度或加大辐照输出剂量。  相似文献   

4.
激光照射血液荧光光谱的初步研究   总被引:12,自引:2,他引:12  
采用OMA—II微弱信号检测系统研究了人血液荧光光谱在激光照射下的变化情况。结果表明:在632.8nmHeNe激光诱导下,不同血液在670nm,730nm,981nm附近出现三个荧光峰;荧光强度在一定范围内与照射激光功率呈线性变化关系;随着激光照射时间的增加,三个峰位上的荧光强度下降,8分钟后趋于稳定值;在激光照射过程中,三个峰位出现不同数值的移动,同时在670nm和730nm两个荧光峰之间出现了竞争。  相似文献   

5.
XeCl准分子激光消融几种生物组织的实验结果   总被引:2,自引:2,他引:0  
本文报道了308nmXeCl准分子激光对人牙硬组织和猪肉软组织消融的实验研究结果,在国内首次开展了XeCl准分子激光牙科应用的基础研究,为准分子激光在牙科的临床应用提供了实验依据。  相似文献   

6.
本文通过半导体激光等辐照源对DNA辐照,研究激光、紫外、普通红光对DNA吸收光谱的影响。发现激光(660nm)与紫外(峰值波长254nm)均能使DNA吸收峰值改变,表明它们均能被DNA吸收,与DNA发生作用,从而使DNA构型发生变化,但激光、紫外与DNA作用机理是不同的。而普通红光(峰值波长660nm)对DNA光谱无甚影响,这说明了激光与DNA作用的非线性共振吸收存在。并发现在激光辐照DNA时,激光剂量不同以及DNA溶液浓度不同,对DNA光谱的影响也不同。这些结果对激光育种和激光生物学实验有一定参考价值。  相似文献   

7.
本文根据数理统计的原理和方法,初步讨论了农业激光生物效应可比性实验的问题。  相似文献   

8.
用紫外可见分光光度计,对受He-Ne激光辐照过的DNA溶液进行扫描。发现209nm吸收峰降低了10%,表明632.8nmHe-Ne激光波DNA吸收而引起其构象变化。He-Ne激光波长632.8nm,约为209nm的3倍,恰好为我们理论研究的激光与DNA相互作用非线性系统的超谐波共振波长。因此该实验结果使我们的理论结果得到了初步验证。  相似文献   

9.
激光的生物学效应研究   总被引:4,自引:0,他引:4  
本文通过分析多种激光(十五种激光器,波长从266nm—447.2×l03nm)对生物体(九十多种生物,如果把品种计算在内,则大约200多种)的生物学效应研究发现:①不同波长激光都能对生物体产生作用;②激光对动物、植物、微生物均能产生生物学效应;③低剂量辐照对生物体主要是刺激作用,随着剂量增加则产生抑制、损伤,以及诱变和致死作用;④激光对60Co—γ射线的辐射损伤有一定的修复作用;⑤低功率激光对生物体的作用主要在于其电效应和电磁场效应(关于这个方面,将另文详细讨论)。  相似文献   

10.
应用可变脉宽YAG倍频532nm波长激光治疗81例血管性皮肤病患者。每两个月重复一次,观察疗效。发现皮损表浅、婴幼儿、血管扩张程度轻者疗效好。81例患者经过1~3次治疗,痊愈38例,显效28例,有效率81.5%。说明YAG倍频激光治疗血管性皮肤病有明显疗效,副反应少,是一种行之有效的方法。  相似文献   

11.
目的:利用532 nm脉冲激光、532 nm连续激光和氙灯对K562细胞进行基于5-氨基乙酰丙酸的光动力疗法(ALA-PDT),研究在不同光照条件下细胞抑制率的变化情况,为实现体外ALA-PDT的高效率选择合适的光源。方法:在其他条件相同的情况下,采用不同的光源、不同的光剂量对ALA-PDT组细胞进行辐照,利用O-LYMPUS倒置荧光显微镜和显微镜数码相机系统观察细胞的形态学变化并拍照,利用光学显微镜进行台盼兰拒染法检测细胞的抑制率变化情况。结果:532 nm连续激光和脉冲激光对K562细胞的ALA-PDT抑制率均较低,增加光剂量也不能有效提高ALA-PDT的抑制率;氙灯在功率密度为350 mW/cm2、光照5 min时就能达到最佳的光剂量,此时单纯光照对K562细胞的光损伤作用很小且ALA-PDT效率很高。结论:宽光谱、高功率的氙灯对K562细胞的ALA-PDT效果远优于532 nm激光,对体外ALA-PDT实验比较适用。  相似文献   

12.
目的 :研究 10 64nm和 53 2nm波长激光在激光能量为 14 0mJ/pulse(脉冲 )时对犬心肌切割效率。方法 :用Q开关Nd :YAG 10 64和 53 2nm波长脉冲激光分别照射犬离体和在体心肌组织 ,光学显微镜和偏振光学显微镜行组织学分析 ,观察不同条件下激光切割组织的深度和光热对组织的损伤。结果 :离体和在体实验 ,10 64nm波长激光的切割效率高于 53 2nm(p <0 .0 1)。在体和离体实验显示 10 64nm激光能量和重复率相同时 ,所致的切割效率无明显差异 (p >0 .0 5) ,血液对 10 64nm激光的切割效率影响较小。相反 ,在 53 2nm时血液对其影响较大 ,相同的激光能量和重复率 ,离体实验切割效率高于在体 (p <0 .0 1)。 10 64nm激光所致的光热和机械损伤均轻于 53 2nm激光。结论 :在切割效率方面 ,10 64nm激光比 53 2nm更适用于TMLR。 10 64nmQ开关Nd :YAG激光可通过光导纤维传输 ,是TMLR的一个有潜力的激光源  相似文献   

13.
低强度532nm与633nm激光血管内照射生物效应比较   总被引:5,自引:1,他引:5  
目的:研究同等照射条件的低强度532nm与633nm激光血管内照射对家兔白细胞计数与淋巴细胞凋亡的影响,比较两种激光生物效应的特点。方法:用532nm和633nm激光对健康日本大耳白家兔血管内照射,平均照射功率均设在5mW左右,照射总能量约12J。两组家兔均于照前及照后1d、4d、7d、11d进行外周血白细胞计数,于照前及照后1d、5d进行淋巴细胞凋亡分析。结果:532nm激光照射后,家兔外周血白细胞计数表现为先显著升高后趋向恢复,633nm激光照射后白细胞计数变化类似,但与照前相比升高不明显;与照前相比,两组家免外周血淋巴细胞凋亡比例于照后1d均明显降低,照后5d均显著升高;两组家兔相比,照射后白细胞计数差别明显,但淋巴细胞凋亡比例差异不显著。结论:同等照射条件下,低强度532nm与633nm激光照射血液的生物效应相似,都可以促进白细胞的代谢更新,只是532nm激光的效应略强一些。  相似文献   

14.
本文采用双积分球测量系统和Inverse Add ing-Doub ling方法,研究了自然和热凝固的人肝组织对532nm的KTP激光和1 064 nm的Nd:YAG激光的光学特性。结果表明:热凝固的人肝组织对532 nm的KTP激光的吸收系数较自然的肝组织的吸收系数增大了23.5%(P<0.05),热凝固的肝组织对1 064 nm的Nd:YAG激光的吸收系数较自然的肝组织的吸收系数减小了34.3%(P<0.05)。热凝固的人肝组织对532 nm的KTP激光的散射系数较自然的肝组织的散射系数增大了4.50倍(P<0.05),热凝固的肝组织对1 064 nm的Nd:YAG激光的散射系数较自然的肝组织的散射系数增大了6.41倍(P<0.05)。热凝固的人肝组织对532 nm的KTP激光的各向异性因子较自然的肝组织的各向异性因子减小了5.47%,热凝固的肝组织对1 064 nm的Nd:YAG激光的各向异性因子较自然的肝组织的各向异性因子减小了1.95%。  相似文献   

15.
OBJECTIVE: We evaluated the use of a high power, diode pulsed solid-state laser emitting 532 nm light for immunofluorescence applications. We compared the sensitivity and utility of this laser with the standard 488 nm excitation. METHODS: A flow cytometer was equipped with both a 488 nm and a 532 nm laser; fluorescence emissions from each laser were collected using the same filters and the same detector system. Cells or compensation beads (e.g. latex beads coated with anti-kappa antibodies) were stained with monoclonal antibodies conjugated to phycoerythrin (PE) as well as the PE tandem dyes TRPE, Cy5PE, Cy5.5PE, and Cy7PE. The sensitivity of detection of these reagents as well as those in heavily compensated channels was quantified by measuring the spreading error for a primary detector into a secondary detector. RESULTS: Measurement of the fluorescence emission of PE and PE-tandem dyes was considerably more sensitive when using 532 nm excitation (150 mW) as compared with 488 nm excitation (20 mW). In addition, as the absolute number of photoelectrons collected was greater, there was less measurement-error-induced spread into the compensated channels. As an example, when comparing the spreading error of PE labeled cells into the TRPE detector, the green laser was found to be 15-fold more sensitive as compared with the blue laser. In addition, the blue laser produced more autofluoresent signal from cells as compared with the green laser. Together, these advantages of the 532 nm excitation line provides for a significantly improved detection of immunofluorescence staining.  相似文献   

16.
The overall objective of this paper is to develop a more sensitive and less costly technique of laser irradiation of spermatozoa at certain wavelengths and exposure times suitable for improvement of buffalo semen quality. A 532 nm continuous wave (CW) DPSS laser light has been used to irradiate buffalo semen for different time intervals. Three semen pools from three different bulls (Bubalus bubalis) were used in the experiment, each pool was divided into six groups : control (not irradiated), and the other five were exposed to laser light for 1, 2, 3, 4 and 5 minutes with fluencies of 0.076, 0.15, 0.23, 0.31, and 0.38 Joule/cm2 respectively at an output power 1mW. The results show that the semen quality parameters increase under the effect of laser irradiation. Maximum improvement in the semen quality has been reached after 4 minutes of exposure. Such results indicate the possibility of adopting laser irradiation as an easy and straightforward technique for in situ improvement of the semen quality to optimize the artificial insemination conditions.  相似文献   

17.
Flow cytometers typically incorporate expensive lasers with high-quality (TEM00) output beam structure and very stable output power, significantly increasing system cost and power requirements. Red diode lasers minimize power consumption and cost, but limit fluorophore selection. Low-cost DPSS laser pointer modules could possibly offer increased wavelength selection but presumed emission instability has limited their use. A $160 DPSS 532 nm laser pointer module was first evaluated for noise characteristics and then used as the excitation light source in a custom-built flow cytometer for the analysis of fluorescent calibration and alignment microspheres. Eight of ten modules tested were very quiet (RMS noise < or = 0.6% between 0 and 5 MHz). With a quiet laser pointer module as the light source in a slow-flow system, fluorescence measurements from alignment microspheres produced CVs of about 3.3%. Furthermore, the use of extended transit times and < or =1 mW of laser power produced both baseline resolution of all 8 peaks in a set of Rainbow microspheres, and a detection limit of <20 phycoerythrin molecules per particle. Data collected with the transit time reduced to 25 micros (in the same instrument but at 2.4 mW laser output) demonstrated a detection limit of approximately 75 phycoerythrin molecules and CVs of about 2.7%. The performance, cost, size, and power consumption of the tested laser pointer module suggests that it may be suitable for use in conventional flow cytometry, particularly if it were coupled with cytometers that support extended transit times.  相似文献   

18.
采用双积分球系统和光辐射测量技术的基本原理 ,以及运用生物组织的光学模型 ,研究了 5 32nm和80 8nm激光及其线偏振激光辐照人正常膀胱和膀胱癌组织的光学特性 .结果表明 :膀胱癌组织对同一波长的激光或其线偏振激光的衰减明显较正常膀胱组织的要大 ,膀胱癌组织对 5 32nm和 80 8nm激光的衰减均较其线偏振激光的要略大一些 .膀胱癌组织对 5 32nm和 80 8nm激光及其线偏振激光的衰减明显较正常膀胱组织的要大 .正常膀胱或膀胱癌组织对同一波长的激光及其线偏振激光的折射率均没有明显的差异 ,膀胱癌组织对 5 32nm和80 8nm激光的折射率比正常膀胱的明显要大 .Kubelka Munk二流模型下 ,两种组织对同一波长的激光或其线偏振激光的光学特性均有显著性差异 (P <0 0 1) .同一组织对不同波长的激光及其线偏振激光的光学特性也有显著性差异 (P <0 0 1) ,正常膀胱组织对同一波长的激光及其线偏振激光的光学性有明显差异 ,而膀胱癌组织对同一波长的激光及其线偏振激光的光学特性则没有明显差异 .膀胱癌组织对 5 32nm和 80 8nm激光及其线偏振激光的前向散射通量i (x)、后向散射通量 j (x)、总散射通量I (x)的衰减均较正常膀胱组织的明显要大得多 ,且其i (x)均明显较j (x)要强  相似文献   

19.

The impact of pulsed laser irradiation on the marine biofilm forming bacterium Pseudoalteromonas carrageenovora was investigated in the laboratory by monitoring mortality and the post-irradiation growth pattern. The impact of laser irradiation on bacterial mortality increased with the duration of irradiation. Laser irradiation at 532 nm (0.1 J cm m 2 ) for 15 min resulted in a 53% cell mortality immediately after irradiation. However, the impact after a period of 5 h (delayed impact) was more severe. The growth pattern of irradiated samples showed a prolonged lag phase compared to the reference, due to a reduction in total viable counts (TVC) in the irradiated samples. Nucleic acid staining is suggested to be a promising technique for monitoring laser inflicted bacterial mortality. Thus, the results suggest that laser irradiation could be considered as an alternative technique to reduce the number of biofilm forming bacteria and thereby biofilm formation on hard surfaces.  相似文献   

20.
We discuss fluorescence as a method to detect polycyclic aromatic hydrocarbons and other organic molecules, as well as minerals on the surface of Mars. We present an instrument design that is adapted from the ChemCam instrument which is currently on the Mars Science Lander Rover Curiosity and thus most of the primary components are currently flight qualified for Mars surface operations, significantly reducing development costs. The major change compared to ChemCam is the frequency multipliers of the 1064 nm laser to wavelengths suitable for fluorescence excitation (266 nm, 355 nm, and 532 nm). We present fluorescence spectrum for a variety of organics and minerals relevant to the surface of Mars. Preliminary results show minerals already known on Mars, such as perchlorate, fluoresce strongest when excited by 355 nm. Also we demonstrate that polycyclic aromatic hydrocarbons, such as those present in Martian meteorites, are highly fluorescent at wavelengths in the ultraviolet (266 nm, 355 nm), but not as much in the visible (532 nm). We conclude that fluorescence can be an important method for Mars applications and standoff detection of organics and minerals. The instrument approach described in this paper builds on existing hardware and offers high scientific return for minimal cost for future missions.  相似文献   

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