论文部分内容阅读
试图用更方便而精确的方法代替手工制作生化研究所需要的组织标本时,可以利用激光束作为显微解剖刀。微激光束系统由一架显微镜和一个激光装置组成,后者包括一台氮脉冲激光器(输出功率达40千瓦)和一台氦氖连续波激光器(输出功率为0.5毫瓦)。氮激光器用以产生紫外辐射能,可供组织解剖的需要,而氦氖激光器能发射光谱中的红光,用来对目标作标记,并对该系统作光学调整。用微激光束系统与显微镜的步进台自动控制相结合,能以手工无法达到的精度和速度制作标本。扫描电子显微照片表明,在用紫外激光作的显微制备物的切口边缘只有微小的结构变化,但还是能显示出老鼠的肝、心脏和大脑的各种酶明显减活(deactivation)。用非相干光源和液体染料激光器所作的研究表明,在用长波(比如590毫微米)切割时有可能避免使酶的活性减弱。激光显微解剖比用手工的显微制备具有明显的优点,因为它可重复,很精确,化费的时间相当短。
When trying to replace the hand-made tissue samples needed for biochemical research with more convenient and precise methods, the laser beam can be used as a microsurgical scalpel. The micro-laser system consists of a microscope and a laser unit. The latter includes a nitrogen pulsed laser (output of 40 kW) and a helium-neon continuous wave laser (output of 0.5 mW). Nitrogen lasers are used to generate ultraviolet radiation for anatomical purposes. HeNe lasers emit red light in the spectrum to mark targets and make optical adjustments to the system. Using a combination of a micro-laser beam system with a microscope step-by-step automatic control, specimens can be made with precision and speed that can not be achieved by hand. Scanning electron micrographs show that there is only slight structural change at the nicked margin of the microtrude made with UV laser but still showing significant deactivation of various enzymes in rat liver, heart and brain. Studies using incoherent light sources and liquid dye lasers have shown that it is possible to avoid diminishing enzyme activity when cutting with longwaves (such as 590 nm). Laser microdissection has significant advantages over manual microdissection because it is reproducible, accurate and costly to implement.