倍频Nd：YAG激光对钝顶螺旋藻的诱变效应

利用倍频 Nd:YAG激光 (波长 53 2 nm,功率 50 0 m W,功率密度 1 60 m W/cm2 )诱变钝顶螺旋藻 ,辐照时间为 1 5min、1 0 min、5min通过测定藻丝形态参数、叶绿素 a、β 胡萝卜素、生长速度 ,比较倍频 Nd:YAG激光对钝顶螺旋藻生长的影响。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 ;1 5min,1 0 min辐照组出现螺旋变松驰 ;1 0 min,5min辐照组促进藻的生长和叶绿素 a含量提高 ,使生长速度提高。三个诱变时间剂量都有利于 β 胡萝卡素积累 ,含量增幅最高达 2 2 .3 %。     

半导体激光对紫球藻生物学效应的影响

采用波长650nm,功率40mW,功率密度13W／cm^2的半导体激光,对紫球藻（Porphyridium cruentum)进行诱变,辐照时间分别为5min、10min、20min。通过对紫球藻每天细胞数、叶绿素a、第7d细胞干重和胞外多糖产量的测定可知：与对照组比较,3个处理对紫球藻生长及胞外多糖产生影响,5min、10min均有不同程度的促进作用,其中5min作用最明显,而20min则有抑制作用。     

Ar+激光、Nd:YAG激光辐照亚心形扁藻生物学效应初探

采用Ar^＋激光（488 nm,照射时间分别为10 min、20 min、30 min）、Nd：YAG（1064 nm,照射时间为1 min、2 min、3 min）辐照扁藻,通过细胞计数以及扫描色素的吸收光谱研究激光辐照扁藻的生物效应.研究结果表明：非色素吸收峰的激光可以产生激光生物效应;不同波长,不同剂量的激光辐照扁藻可以表现出相类似的生物效应;Ar＋辐照20 min、Nd：YAG辐照2 min可以刺激扁藻生长,明显提高色素吸收光密度值,促进光合作用的进行.文中对不同激光辐照扁藻所产生的生物效应进行了比较和探讨.     

倍频Nd：YAG激光对钝项螺旋藻的诱变效应

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     

自然和热凝固的人肝组织对KTP/YAG激光的光学特性的比较研究

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%。     

532 nm波段连续激光对视网膜和脉络膜生物学作用的观察

目的：探讨532nm波段激光不同光剂量参数对眼底组织的损伤特点及损伤阈值。方法：以新西兰兔为实验对象,532nm连续激光照射眼底,眼底光斑直径1．5mm～2．5mm,功率密度从500mW／cm^2：～2400mW／cm^2,照射时间100s～300s,每组参数10个光斑。在照射后1h和24h进行眼底观察和荧光眼底造影,计算三种照射时间情况下视网膜的损伤阈值。结果：在照射后第1h,功率密度为902mW／crn2,照射时间300s开始出现视网膜灰色改变,病灶范围接近照光面积,在24h后颜色微加重。随着照光剂量的增加,在功率密度达1479mW／cm2,照射时间300s,照射后1h出现视网膜灰白色改变,在24h后出现脉络膜出血;而且随着照光剂量的增加,病灶范围扩大越明显。出血量越多。随着照光剂量的减少,当功率密度1003mW／cm^2,照射时间200s时,在照光后1h眼底没有改变,24h出现视网膜灰白色改变,面积接近照光面积;光剂量降低到1002mW／cm^2,照射时间100s时,在24h才出现视网膜灰白色改变,变化的视网膜范围小于照光面积。统计学计算在照射时间为300s、200s和100s,照光后1h视网膜损伤阈值分别为911．15628mW／cm^2,1167．64770mW／cm^2,1513．89832mW／cm^2,24h视网膜损伤阈值分别为827．09664mW／cm^2。1003．73143mW／cm^2,1154．17863mW／cm^2。结论：在光线照射后24h之内,视网膜损伤是一个逐渐增强的过程。从视网膜没有明显可见改变到视网膜出现灰白色可见损伤,变化范围从小于照光面积到接近照光面积,甚至超过照光面积,并出现脉络膜出血,出血面积随着照光剂量的增加而范围变大。相同能量密度的光剂量对视网膜损伤轻重取决于激光的功率密度。     

不同激光辐照对盐生杜氏藻生长及β-胡萝卜素累积的影响研究

用YAG、LD和Ar 三种不同激光辐照处理盐生杜氏藻(Dunaliella salina)细胞,通过对辐照前后盐生杜氏藻的生长速率和色素含量进行测定比较,研究不同激光处理对盐生杜氏藻的生理刺激效果。实验结果表明:当YAG激光辐照剂量超过1min时,对盐生杜氏藻细胞的增殖有明显的抑制作用,并抑制其胡萝卜素的合成;LD激光在辐照剂量为3min~5min能促进细胞增殖,其中5min剂量的处理组,生长速率较对照组提高190%,叶绿素和类胡萝卜素的含量,分别提高27.2%和24.4%;Ar 激光在辐照剂量为5min~30min范围内能促进类胡萝卜素的积累,与对照组相比,分别提高18.5%~130.9%,但在这剂量范围内,Ar 激光抑制其生长,同时对不同激光辐照对盐生杜氏藻所产生的生物学效应机理进行了初步探讨。     

不同激光不同能量对红色毛癣菌的体外抑制评估及部分机制的探讨

目的探讨多种激光在不同的能量下对红色毛癣菌的体外抑制作用以及可能的作用机制。方法将Q开关Nd:YAG 532nm激光、Q开关Nd:YAG 1064nm激光、长脉宽Nd:YAG1064nm激光和强脉冲光分为不同能量组及未照光组,体外照射红色毛癣菌的菌落,观察第0、1、3、7天时菌落直径的变化差异,用酶联免疫吸附测定激光照射后红色毛癣菌产生角蛋白酶的活性。结果与未照光组相比,上述激光在低能量时对红色毛癣菌的菌落直径与角蛋白酶活性无明显影响。2～4J/cm~2能量Q开关Nd:YAG 532nm激光、4～8J/cm~2能量Q开关Nd:YAG 1064nm激光、4J/cm~2长脉宽Nd:YAG 1064nm激光能显著抑制菌落的生长,红色毛癣菌角蛋白酶的活性出现明显下降。结论 2～4J/cm~2能量Q开关Nd:YAG 532nm激光、4～8J/cm~2能量Q开关Nd:YAG 1064nm激光、4J/cm~2长脉宽Nd:YAG 1064nm激光能抑制红色毛癣菌生长及角蛋白酶的活性。     

倍频Nd：YAG激光对紫球藻生长与胞外多糖产量的影响

紫球藻经Nd:YAG激光（波长1060nm)照射,以不同时间设置处理剂量,比较紫球藻细胞活力,生长速率,生物量,胞外多糖产量等方面的变化。高剂量处理组（Y-20、Y-30和Y-40）致死率为17-44%,继代培养后生长迅速,K值分别比对照组提高18%、23.4%和15.3%,各处理组培养10天后收获的生物量与对照组无显著差异,但胞外多糖产量均有较大幅度提高,增幅达50-150%。此外,YAG激光照射对藻细胞叶绿素含量也有影响,YAG激光有望成为紫球藻优良藻株选育的较佳诱变剂。     

倍频Nd∶YAG激光对紫球藻生长与胞外多糖产量的影响

紫球藻经Nd:YAG激光(波长1060 nm)照射,以不同时间设置处理剂量,比较紫球藻细胞活力、生长速率、生物量、胞外多糖产量等方面的变化.高剂量处理组(Y-20、Y-30和Y-40)致死率为17～44%,继代培养后生长迅速,K值分别比对照组提高18%、23.4%和15.3%.各处理组培养10天后收获的生物量与对照组无显著差别,但胞外多糖产量均有较大幅度提高,增幅达50～150%.此外,YAG激光照射对藻细胞叶绿素含量也有影响.YAG激光有望成为紫球藻优良藻株选育的较佳诱变剂.     

激光及激光生物学发展概况

本文介绍了激光、激光应用和激光生物学发展概况     

A quantitative evaluation of the use of medical lasers in German hospitals

The laser has become an integral part of modern medicine, procedures based on this technique have found their way into a multitude of medical disciplines. There is, however, no data available on the detailed quantitative development of laser use in the medical sector. This fact gave rise to the idea of the present study, which analyzed the raw data of the quality report of German hospitals with respect to this subject. Over the 9 years of report, a steady increase in the cumulative number of cases was evident, although not all body regions in which the medical laser is used followed this trend. The CO₂ laser was found to be the most commonly applied laser, even though a large spectrum of different laser types is used. Based on the present study, the importance of the laser for medical purposes can be confirmed.     

Comparative analysis of two laser wavelengths in the stimulation of acupuncture points for analgesic effects in an animal model

This study compares the effectiveness of two laser wavelengths for stimulating acupoints in an experimental model of acute postoperative pain. Forty-five Wistar rats were randomly assigned to receive treatment on their left hind paw, contralateral to a surgical procedure. Laser treatments were performed with Green Laser—GL (532 nm, 70 mW and 7 J/cm² of energy), Red Laser—RL (660 nm, 100 mW and 7 J/cm² of energy), or with Laser Off—LO. After each application, the animals were evaluated with a Von Frey analgesiometer to check for painful sensitivity on their right (with surgery) and left (without surgery) hind paws. Neuropeptides and cytokine levels in the incision site tissue of the right paw were measured by ELISA after 1, 6 and 24 hours. It was possible to observe that, in this pain model, both lasers promoted analgesia and that the GL altered the levels of TNF-α and IL-1β.     

Development of a dual joystick‐controlled laser trapping and cutting system for optical micromanipulation of chromosomes inside living cells

A multi‐joystick robotic laser microscope system used to control two optical traps (tweezers) and one laser scissors has been developed for subcellular organelle manipulation. The use of joysticks has provided a “user‐friendly” method for both trapping and cutting of organelles such as chromosomes in live cells. This innovative design has enabled the clean severing of chromosome arms using the laser scissors as well as the ability to easily hold and pull the severed arm using the laser tweezers. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

准分子激光眼科治疗机中激光器控制实现

准分子激光眼科治疗机可以用来进行近视、远视、散光等屈光不正的矫正手术。其中激光器的控制为手术提供能量稳定的激光脉冲,是对手术安全性、可靠性的重要保证。本文简述了一准分子激光眼科治疗机的整体组成部分,并详细描述了激光器的控制部分:计算机与激光器的通信控制、激光发射停止控制、充换气流程控制。目前,这种准分子激光治疗机已经应用于临床,并取得了良好的效果。     

308nm准分子激光治疗白癜风进展

白癜风是一种常见的后天色素脱失性皮肤黏膜疾病。虽然传统治疗方法很多,但是大多数疗法疗效欠佳,且有一定副作用,因而,白癜风的治疗成为一个临床治疗难题。近年来,308 nm准分子激光,一种治疗白癜风的新型激光治疗手段,以其显效快速、治疗次数少、累计剂量低、不累及正常皮肤、副作用少、缓解期相对长等特点在临床上得到广泛应用且被多数患者所接受。本文就308 nm准分子激光治疗白癜风的作用机制、临床应用优势、临床疗效、不良反应、影响因素及联合治疗疗效简单作一综述,并分析影响疗效的相关因素:病人年龄、病程、皮肤类型、皮损部位、大小及治疗次数等,以供临床治疗参考。     

CO2激光、LD激光联合治疗牙龈瘤46例疗效观察

目的：研究CO2激光、LD激光联合治疗牙龈瘤及保存牙体组织的临床疗效。方法：对46例口腔牙龈瘤患者发病的年龄,性别,好发部位进行分析,采用CO2激光、LD激光联合治疗机,先用CO2激光束切割肿瘤,而后CO2激光气化肿瘤波及牙齿的牙周膜,术后第二天用LD激光,每日一次,每次15分钟,连续5天照射手术创面。结果：46列牙龈瘤患者,42例一次治疗痊愈,4例复发,二次手术后无复发,手术疗效、治愈率100％。结论：CO2激光、LD激光联合切除牙龈瘤与传统的手术方法,治疗疗效机理进行了对照,其特点是保存了肿瘤波及的牙齿,不造成组织缺损,还具有手术时间短,出血少,愈合快等优点。     

HeNe激光对瘢痕组织影响的实验研究

目的 :寻求瘢痕组织的康复疗法。方法 :家兔 2 0只 ,在臀部一侧人工形成瘢痕。随机分为激光治疗组和对照组 ,每组 1 0只。对激光治疗组家兔于术后第 3天开始用低能量 He Ne激光照射治疗 ,每天一次 ,每次1 5分钟 ,连续照射 1 0天。于术后第 2 0天 ,将家兔全部处死 ,对每只做过实验的臀部 ,均整块地切其软组织做病理检查。结果 :激光治疗组感染消失和切口愈合平均天数分别为 4 .2天和 5.9天。对照组感染消失和切口愈合平均天数分别为 1 2 .9天和 1 4 .8天。显微镜下可见表皮增厚 ,瘢痕及横纹肌退变等异常改变。这些变化以激光治疗组为最轻 ,与对照组比 P<0 .0 1 ,有非常显著差异。结论 :早期应用 He Ne激光照射治疗 ,有防治瘢痕形成及促进瘢痕软化的作用。     

A comparative study of thermal effects of 3 types of laser in eye: 3D simulation with bioheat equation

The application of laser in ophthalmology and eye surgery is so widespread that hardly can anyone deny its importance. On the other hand, since the human eye is an organ susceptible to external factors such as heat waves, laser radiation rapidly increases the temperature of the eye and therefore the study of temperature distribution inside the eye under laser irradiation is crucial; but the use of experimental and invasive methods for measuring the temperature inside the eye is typically high-risk and hazardous. In this paper, using the three-dimensional finite element method, the distribution of heat transfer inside the eye under transient condition was studied through three different lasers named Nd:Yag, Nd:Yap and ArF. Considering the metabolic heat and blood perfusion rate in various regions of the eye, numerical solution of space–time dependant Pennes bioheat transfer equation has been applied in this study. Lambert–Beer's law has been used to model the absorption of laser energy inside the eye tissues. It should also be mentioned that the effect of the ambient temperature, tear evaporation rate, laser power and the pupil diameter on the temperature distribution have been studied. Also, temperature distribution inside the eye after applying each laser and temperature variations of six optional regions as functions of time have been investigated. The results show that these radiations cause temperature rise in various regions, which will in turn causes serious damages to the eye tissues. Investigating the temperature distribution inside the eye under the laser irradiation can be a useful tool to study and predict the thermal effects of laser radiation on the human eye and evaluate the risk involved in performing laser surgery.     

Nd:YAG激光治疗特殊部位尖锐湿疣的疗效观察

目的：观察Nd：YAG激光治疗位于尿道口、阴道口、肛门及肛周的难治性尖锐湿疣的疗效。方法：将61例特殊部位的尖锐湿疣的患者随机分为实验组（31例）和对照组（30例）,实验组采用Nd：YAG激光机治疗,对照组采用普通CO2激光治疗机,随访半年观察两组的创面愈合情况、治愈率及复发率。结果：采用Nd：YAG激光治疗的实验组一次治愈率为80．64％,高于对照组的一次治愈率56．67％（x^2=4．087,P〈0．05）,但两组的总治愈率无显著性差异（x^2=1．198,P〉0．05）。实验组复发率为22．58％,低于对照组的复发率46．67％。两者有显著性差异（x^2=3．918,P〈0．05）。激光术后第5天实验组的愈合率45．16％高于对照组的愈合率20．00％,两者有显著性差异（x^2=4．380,P〈0．05）;第7天实验组的愈合率为87．09％高于对照组的愈合率60．00％,两者有显著性差别（x^2=4．469,P〈0．05）;第10天实验组的患者全部愈合,愈合率为100％,高于对照组的愈合率83．33％（P=0．024〈0．05）。结论：Nd：YAG激光治疗特殊部位尖锐湿疣效果好,创面愈合快,复发率低。