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Since the beginning of history, man has been fascinated by the idea of living for ever, of winning the fight against death and disease. So far, this has only remained a dream, though a very powerful one. Many people have wondered whether it would be possible to find a way to preserve human bodies, and what would be the best way to preserve human bodies.It has long been known that meat or fruit can be kept fresh for long periods by freezing; in ancient China, for example, food was stored with ice to keep it fresh. This method could also be useful for preserving humans, and in fact many people have explored this possibility.However, most living beings that exist under warm conditions die when frozen. This is because of the harmful effects of freezing ice crystals (晶体), which are not only larger than the volume of the water originally in the cells, but also form sharp cutting shapes that harm the cells.In the 1940s, Dr. B.J. Luyet and a group of scientists in England were working on the problem of freezing cells without damaging them. Since the harm caused by ice crystals was the main cause of the damage, Luyet suggested removing some or all of the water from the cells before freezing them.Using living cells from chicken, Luyet and his assistants discovered that they could partly dry the chicken cells, using a mixture of the white part of an egg and glycerin (丙三醇), a clear, thick liquid made chiefly from fats and oils. Some success was obtained. The chicken cells were dried, frozen for a period of time, and then carefully unfrozen. Almost all the cells recovered when they reached normal temperatures.Since then, the cooling of whole animals to a temperature very much below freezing point for later unfreezing has become more of a possibility, and the glycerin method would probably be used to accomplish this. When this can be done completely and successfully, science will have moved much closer to its aim of freezing and storing incurable patients until the day they can be cured. The passage is mainly about ______.
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My husband and I took off to Bafflo to help Mum move out of her apartment in Bafflo, New York. The plan was to pack everything into her van so that she could drive around visiting families and friends for the next ten days before heading back to her home in Florida.After dinner we headed back onto the road, Mum in the van with us behind in our rental car. The next moment changed everything: a deer jumped out in front of the van and Mum ran right into it. There was nothing she could do. It was awful. Police arrived. Calls were placed. The tow truck arrived. We moved essentials into our car and made plans to get Morn to a hotel near the garage. Everything fell into place in a mechanical way. And I worried about Mum, of course, but what troubled me most was the deer because it wasn"t dead. When the police officer shone his light around the accident scene, two beautiful brown eyes were frozen in the beam of light. It was lying down on someone"s front lawn, still, shocked, but very alive.I couldn"t even look at it. I asked the police officer if he could shoot it, but because it was a residential area, other methods were needed. The officers felt its legs to confirm that they were not broken, and gently pushed it, hoping that the push would inspire the poor animal to turn. But it sat there, probably suffering from internal injuries. And that caused me to feel a deep and powerful sadness. If that was a person lying in the ditch, there would be ambulances and doctors busily working to relieve pain and save life. But no, it was an animal, and there is no justice for animals. Why did the author and her husband move essentials from the van into their own
Speaker A: Let"s go back to our talk. Speaker B: You were talking about your trip to Africa. Speaker A: Oh, yeah.
Speaker A: This is Peter Jackson calling. Is Bob in, please Speaker B: I"m afraid he"s out at the moment. Speaker A: Yeah, could you ask him to call Peter at 8964523
Jack: Hey, Jane, let"s go and get a bite to eat. Jane: ______ Jack: How about McDonald"s Jane: Great.
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