激光在我国兽医领域及畜牧生产中的应用

本文概述了激光在我国兽医外科,产科、内科、传染病及畜牧生产等方面的应用情况,以及有关激光的基础理论研究进展。     

生物组织激光消融阈值的光谱特性

在一个宽光谱范围内研究不同激光作用下生物组织的消融,对理解激光与组织间相互作用及开发激光在外科的新应用有着极其重要的意义。其中消融阈值及其与激光波长的函数依赖关系是激光外科研究的重点。阐述了消融阈值的物理描述,并对消融阈值的波长依赖关系进行了初步探讨。     

激光技术在肿瘤治疗中的研究进展

本文就激光治疗肿瘤的三种途径：激光外科疗法,光动力疗法和低能激光照射抗肿瘤免疫抑制效应作了简要的综述。     

半导体激光在口腔临床医疗中的应用和研究进展

激光在口腔领域中的应用越来越多。半导体激光以其诸多的优点,在口腔领域的应用也越来越广泛,现就半导体激光在口腔内科、口腔正畸学、口腔修复学、口腔种植学以及颌面外科等领域的临床应用现状及目前的研究进展加以综述。     

激光在普外的现状与展望：文献综述

自1960年 Maiman 研制成第一台红宝石激光器以后,由于激光以强大集中的能量,不同波长对组织作用的特性及光导纤维的传输等等,赋予了医学一种潜在的革命,因而,六十年代从眼科、皮肤科、外科、妇科及肿瘤科扩展到医学各个领域,包括基础及诊断预防医学.近十余年来由于激光器迅速发展,光纤传输的方便,以及激光——组织间关系的研究成果,使得激光医学更是突飞猛进,加之激光工程技术人员与医务人员紧密合作,为发展激光医学做出了更大的贡献。由于激光医疗极为广泛,这里仅就激光在普外的应用作一文献复习,综述如下:激光应用于普外科在外科领域为最早之学科.1963年开始用较大功率脉冲激光来汔化和烧灼表浅肿瘤,由于存在“飞溅”现象和压力效应而暂停.     

外科新三联疗法治疗糖尿病足的临床观察

目的:观察外科新三联疗法(外科换药-威伐激光-成纤维细胞生长因子)治疗糖尿病足溃疡的临床疗效和安全性。方法:将57例糖尿病足溃疡患者随机分为2组。对照组28例,采用外科换药辅以成纤维细胞生长因子外敷治疗;治疗组29例,在对照组治疗的基础上配合威伐激光照射治疗。疗程为8周,观察两组患者的治疗有效率、愈合时间和不良反应的发生情况。结果:治疗组和对照组的有效率分别为86.21%、57.14%,治疗组显著高于对照组(P0.05);且治疗组溃疡的愈合时间(39.40±2.24天)较对照组(50.67±2.31天)明显缩短(P0.01)。此外,两组患者均无明显的不良反应发生。结论:外科新三联疗法(外科换药-威伐激光-成纤维细胞生长因子)是治疗糖尿病足溃疡的有效方法,且安全性好。     

前言

激光是上个世纪三大发明之一,具有划时代的意义.而激光生物医学是随着它的问世而产生的一门新兴学科.60年代第一台红宝石激光器问世,70年代即应用于医学.激光的应用涉及医学领域的多个学科,在治疗方面可分为强激光治疗、弱激光治疗和光动力疗法.强激光治疗是应用激光作为能量载体的特性,方法成熟、机制清楚,是外科治疗的有力手段.弱激光的治疗则是临床应用较早和较普及的治疗方法,但其治疗机制尚不清楚,疗效不确切.目前,弱激光的治疗主要是体表局部照射,或作为针灸的替代方法,用以照射穴位.光动力疗法是激光、光敏剂二者的结合,是应用光敏剂的光化学作用和组织的高度选择性来达到治疗目的的一种方法,其应用范围已从肿瘤治疗扩展到如鲜红斑痣、类风湿关节炎等,是激光医学最为活跃的一个领域.在诊断方面,应用光敏剂+单克隆抗体+时间分辨成像技术可望提高早期肿瘤诊断的准确率,用激光的方法检测血糖以实现完全无创检测.又如OCT、共聚焦显微镜和流氏细胞仪的应用可能对提高某些疾病的诊断率提供帮助,应用前景广阔.     

CO2激光在拔牙创止血作用的临床观察

拔牙术后出血是一种最常见的并发症。在如何减少病人术后出血以及促进伤口愈合方面,仍是齿槽外科的研究课题。我科应用CO_2激光烧灼拔牙创及牙槽窝内渗血的方法,经临床观察,止血作用明显,效果良好。故报道如下。 资料与方法     

有限元法分析人体皮肤热效应的空间分布

研究了He—Ne激光辐照下人体皮肤组织传热过程温度场空间分布的动态规律。利用有限元法实现皮肤组织非稳态传热方程的模拟计算,获得了人体皮肤组织光致热效应的径向和轴向分布行为及时间变化关系。研究结果对于激光外科临床应用中激光参数的合理确定有一定的指导意义。     

激光在外科应用的新进展

随着激光技术的发展,一门崭新的应用学科——激光医学已逐步形成。国际上最早应用CO_2激光刀施行外科手术是Kaplam博士,他参加研制Sharplan 791型激光刀,用它作过乳房、整形、面颊部良、恶性肿瘤切除、臂部多发性瘤切除、皮肤癌手术等,到1981年已做了552例手术。目前CO_2激光刀和Nd—YAG激光器已广泛应用于外科各个领域,日本Nimsakul应用CO_2激光进行     

Laser surgery: using the carbon dioxide laser.

In 1917 Einstein theorized tha through an atomic process a unique kind of electromagnetic radiation could be produced by stimulated emission. When such radiation is in the optical or infrared spectrum it is termed laser (light amplification by stimulated emission of radiation) light. A laser, a high-intensity light source, emits a nearly parallel electromagnetic beam of energy at a given wavelength that can be captured by a lens and concentrated in the focal spot. The wavelength determines how the laser will be used. The carbon dioxide laser is now successfully employed for some surgical procedures in gynecology, otorhinolaryngology, neurosurgery, and plastic and general surgery. The CO2 laser beam is directed through the viewing system of an operating microscope or through a hand-held laser component. Its basic action in tissue is thermal vaporization; it causes minimal damage to adjacent tissues. Surgeons require special training in the basic methods and techniques of laser surgery, as well as in the safety standards that must be observed.     

Development of head and neck surgery at the end of the XXth century

The development of the surgery of the head and neck tumors seemed to be completed for the end of the seventies by the widespread acceptance of the basic technologies. However, the discovery of two techniques, medical laser and PM-lobe initiated major developments in the surgical oncology of head and neck cancer. Based on our studies, the benefits of use of medical laser in oncology are its fine-tuned topological preciseness, tissue-protection and the lack of bleeding disorders. A special benefit of the medical laser is its ablasticity and the support of tissue repair. The wide-spread use of PM-lobe technique in head and neck surgery was made it possible by the development of various modifications such as the cutan-myocutan and the osteomyocutan ones. By the application of the developed variants we were able to correct the consequences of radical resections and achieved acceptable functional and esthetic status in cancer patients.     

飞秒激光与生物细胞作用机理及应用

飞秒激光是自1960年第一台激光器诞生以来,过去20年间由激光科学发展起来的最强有力的新工具之一。飞秒激光由于脉冲持续时间短、瞬时功率大、聚焦尺寸小的特点,使得其在超快、超强和超精细领域有着广阔的应用前景。其中最重要的一个方向是飞秒激光在生物细胞方面的应用。细胞是生命活动的基本单位。所有的病源微观上都体现在细胞中细胞器的工作,所以用飞秒激光作用在病体的细胞器上达到治疗的目的,是一个很有前景的领域。由于生物大分子和水几乎不吸收近红外光,故应用近红外飞秒激光对细胞进行手术,同时可在不损伤细胞活性的前提下对细胞进行实验。这种激光手术技术已被用于对细胞内结构进行切割和蚀除。介绍了该技术在细胞领域中的一些应用,如纳米手术、基因转染和染色体切割等;还介绍了飞秒激光技术与生物细胞中主要细胞器的祛除的原理、飞秒激光细胞操作与手术系统和实验中荧光成像、多光子成像显微镜等手段。     

飞秒激光在白内障手术中的应用新进展

飞秒激光辅助的白内障手术是目前最热门的白内障手术之一。即在计算机系统引导下利用飞秒激光进行透明角膜切口的制作,晶状体核裂解和晶状体前囊膜的切开,明显降低了传统超声乳化手术中的并发症,具有十分广阔的临床应用前景。然而飞秒激光辅助的白内障手术目前仍然处于临床应用初级阶段,其昂贵的价格是影响其研究和应用的主要原因,手术安全性及远期屈光效果仍然需要长期的随访观察。本文根据文献资料,就飞秒激光在白内障手术中的优势及临床应用的局限性进行综述。     

Analysis of the reasons for not undergoing laser corneal refractive surgery in 611 patients

To determine and analyze the reasons for patients not undergoing laser corneal refractive surgery. A retrospective observational study was conducted to analyze the reasons for not undergoing laser corneal refractive surgery in 611 patients. In this study, 611 (14.34%) among 4,262 enrolled patients did not undergo laser corneal refractive surgery. Among these 611 patients, the common reasons for not undergoing laser corneal refractive surgery were concern about the surgery (366 patients, 59.90%), insufficient corneal thickness (72 patients, 11.78%), too high corneal refractive power (36 patients, 5.89%), dry eye (33 patients, 5.40%), high intraocular pressure (22 patients, 3.60%), poor corrected visual acuity (25 patients, 4.09%), retinal diseases (23 patients, 3.76%) and others (34 patients, 5.56%). The concern about surgery is the primary factor for the patients not undergoing laser corneal refractive surgery.     

Teaching medical physics to general audiences.

By judiciously selecting topics and reading materials, one can teach a full semester course on medical physics appropriate for college students not majoring in the natural sciences. This interdisciplinary field offers an opportunity to teach a great deal of basic physics at the freshman level in the context of explaining modern medical technologies such as ultrasound imaging, laser surgery, and positron emission tomography. This article describes one such course which combines lectures, outside visitors, varied readings, and laboratories to convey a select subset of physical principles and quantitative problem-solving skills. These resources are also valuable for enriching the standard freshman physics sequence for premedical students.     

Microsurgery and laser surgery in conservative operations on the ovary. Experimental research]

In this study we compared two different conservative surgery techniques performed on 12 ovaries of female rabbits: microsurgery and CO2 Laser surgery. After the surgical procedure all the animals were investigated by a Laparotomy to evaluate the post-operative adhesion formation. Histological examinations were performed on 6 ovaries, to evaluate the possible damage to the ovarian parenchyma. We did not find significant differences between the two methods employed, particularly for the adherence formation and the parenchymal thermic damages: no post-operative adhesions were detected respectively in 3 ovaries operated on by microsurgery and 5 by laser surgery; slight adhesions were present in 2 ovaries treated with microsurgery and in 3 with laser surgery; 3 ovaries treated with microsurgery and 2 with laser surgery showed moderate adhesions. Only 2 ovaries treated with microsurgery presented severe adhesions.     

激光医疗的进展：低功率激光治疗在中国

激光医学尤其是低功率激光治疗在中国已成为发展极为迅速的领域之一。低功率激光照射的光生物效应与传统中医针刺穴位经络相结合在中国低功率激光治疗中开辟了广阔的领域,並已广泛应用于临床各专科如内科、皮肤科、眼科、耳鼻喉科、口腔科、妇产科、整形外科、激光针灸及兽医学,成功地治疗了数百种疾病,效果显著。作者近10年来已成功应用激光穴位麻醉拔牙与施行面部整容小手术。1985～1990年以来开创了激光美容外科。低功率激光治疗已被证实在保证激光美容效果的重要性。     

Surgical applications of femtosecond lasers

Femtosecond laser ablation permits non‐invasive surgeries in the bulk of a sample with submicrometer resolution. We briefly review the history of optical surgery techniques and the experimental background of femtosecond laser ablation. Next, we present several clinical applications, including dental surgery and eye surgery. We then summarize research applications, encompassing cell and tissue studies, research on C. elegans, and studies in zebrafish. We conclude by discussing future trends of femtosecond laser systems and some possible application directions. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Laser nanosurgery in cell biology

Since their first use in the early 60's, pulsed lasers have become increasingly popular for their ability to ablate biological tissue. Short laser pulses allow high precision surgery for biological and medical applications with minimal invasiveness. Performing highly targeted manipulation and ablation allows experiments impossible so far in development biology, cellular biology or even assisted reproductive technologies and laser surgery has been increasingly used over the last five years to answer key questions in Biology. Recently, picosecond UV and femtosecond IR laser pulses have been used to cleave microtubules and to severe actin stress fibers in vivo with a spatial precision in the submicrometer range to study their dynamics without affecting cell viability. We review recent findings on the underlying principles of pulsed laser nanosurgery mechanisms showing how the use of ultra short laser pulses increases precision and non-invasiveness of laser surgery. We show how the understanding of the surgical process allows one to distinguish between single cell ablation in living organisms or intracellular nanosurgery in living cells and we review recent applications to the study of forces and the quantification of cytoskeleton dynamics.