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在冰冻断裂复型技术中,为了保持活组织的生活状态,把人工损伤减小到最低程度,Heuser at al首先用液氦做冷却剂,冷却金属至-268.9℃,然后把活组织样品与低温金属块接触,以达到10~4K/秒的快速冷冻速度,用该法冷冻的材料进行复型,获得了15微米玻璃化冷冻深度的复型面,山田英智等改进了Van Harreveld at al的仪器,首先用液氮冷却金属块,用上述方法亦获得了复型。该法制得的复型面虽比Heuser的方法狭窄,但液氮便宜又容易获得,所以此法值得推广。为什么上述学者不用液体浸渍法而用与低温金属相接触的方法冷冻样品呢?这是由于本方法样品冷冻的速率快,可高于10~4K/秒以上。而液氮或液体氟里昂浸渍法最多只可达2.5×10~3K/秒的冻结速率,不易使细胞质迅速玻璃化。快速冻结法就是基于上述原理而设计的。
In the frozen fracture reconstruction technique, in order to maintain the life status of the living tissue and minimize the artificial damage, Heuser at al firstly uses liquid helium as a coolant to cool the metal to -268.9 ° C, and then compares the living tissue sample with a low temperature Metal block in order to achieve fast freezing speed of 10 ~ 4K / sec, using the method of frozen material complex, access to the 15 micron glass transition depth of the complex surface, Hideyuki Yamada, etc. improved Van Harreveld at al’s instrument First, the metal block is cooled with liquid nitrogen, and the re-type is also obtained by the above method. The complex system made by the law although Heuser narrow, but liquid nitrogen is cheap and easy to get, so this method is worth promoting. Why do the above scholars do not use liquid immersion method with low temperature metal in contact with frozen samples? This is because the method of freezing the sample rate can be higher than 10 ~ 4K / s or more. The liquid nitrogen or liquid Freon immersion method up to only 2.5 × 10 ~ 3K / sec of freezing rate, difficult to quickly cytoplasm vitrification. Fast freezing method is based on the above principles and design.