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013 - Dose and Consequence Radiation Sickness · Percheron horse

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  Speaker 1: Section twelve of the Genetic Effects of radiation. This is
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  Speaker 1: a LibriVox recording. All liberyvox recordings are in the public domain.
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  Speaker 1: For more information or to volunteer, please visit LibriVox dot org.
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  Speaker 1: Read by Yoganan The Genetic Effects of Radiation by Isaac
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  Speaker 1: Asimov and Theodosius Dubzanski. Dose and consequence radiation sickness, The
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  Speaker 1: danger of the individual as a result of overexposure to
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  Speaker 1: high energy radiation was understood fairly soon, but not before
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  Speaker 1: some tragic experiences were recorded. One of the early workers
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  Speaker 1: with radiactive materials, Preach Curie, deliberately exposed a patch of
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  Speaker 1: the skin to the action of radioactive radiations and obtained
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  Speaker 1: a serious and slow healing burn. His wife, Marie Curie,
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  Speaker 1: and their daughter Iran Juliot Curie, who spent their lives
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  Speaker 1: working with radiactive materials, both died of leukemia, very possibly
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  Speaker 1: as a result of cumulative exposure to radiation. Other research
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  Speaker 1: workers in the field died of cancer. Before the full
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  Speaker 1: necessity of extreme caution was understood. The damage done to
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  Speaker 1: human beings for radiation could first be studied on a
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  Speaker 1: large scale. Among the survivors of the nuclear bombings of
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  Speaker 1: Hiroshima and Nagasaki in nineteen forty five. Here marked symptoms
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  Speaker 1: of radiation sickness were observed. This sickness often leads to death,
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  Speaker 1: though a slow recovery is sometimes possible. In general, high
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  Speaker 1: energy radiation damage is a complex molecules within a cell
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  Speaker 1: interfering with its chemical missionary to the point in extreme
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  Speaker 1: cases of killing it. Thus, cancers which cannot safely be
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  Speaker 1: reached with surgeon's knife are sometimes exposed to high energy
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  Speaker 1: radiation in the hope that the cancer cells would be
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  Speaker 1: effectively killed. In that manner, the delicate structure of the
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  Speaker 1: genes and chromosomes is particularly vulnerable to the impact of
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  Speaker 1: high energy radiation. Chromosomes can be broken by such variation,
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  Speaker 1: and this is the main cause of actual cell death.
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  Speaker 1: A cell that is not killed outright by radiation may
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  Speaker 1: nevertheless be so damaged as to be unable to undergo
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  Speaker 1: replication and mitosis. If a cell is of a type
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  Speaker 1: that will not, in the codes of nature, undergo division,
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  Speaker 1: the destruction of the mitosis missionary is not in itself
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  Speaker 1: fatal to the organism. A creature like drosophilia, which in
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  Speaker 1: its adult stage has very few cell divisions going on
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  Speaker 1: among the ordinary cells of its body can survive radiation
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  Speaker 1: doses a hundred times as great ass would suffice to
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  Speaker 1: kill a man. In a human being, However, even in
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  Speaker 1: an adult who is no longer experiencing overall growth, there
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  Speaker 1: are many tissues whose cells must undergo division throughout life.
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  Speaker 1: Hair and fingernails grow constantly as a result of cell
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  Speaker 1: division at their roots. The outer layers of skin are
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  Speaker 1: steadily lost through abrasion and are replaced through constant cell
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  Speaker 1: division in the deeper layers. The same is true of
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  Speaker 1: the lining of the mouth, throat, stomach, and interstines. Two
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  Speaker 1: blood cells are continually breaking up and must be replaced
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  Speaker 1: in vast numbers. If radiation kills the mechanism of division
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  Speaker 1: in only some of these cells, it is possible that
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  Speaker 1: those that remain reasonably intact can divide and eventually replace
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  Speaker 1: do the work of those that can no longer divide.
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  Speaker 1: In that case, the symptoms of radiation sickness are relatively
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  Speaker 1: mild in the first place, and eventually disappear past a
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  Speaker 1: certain critical point. When too many cells are made incapable
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  Speaker 1: of division, this is no longer possible. The symptoms which
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  Speaker 1: show up in the growing tissues, particularly as in the
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  Speaker 1: loss of hair, the misshaping or loss of fingernails, the
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  Speaker 1: reddening and hemorrhaging of skin, the alteration of the mouth,
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  Speaker 1: and the lowering of the blood cell count grow steadily
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  Speaker 1: more severe and death follows. End of Section twelve. Radiation
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  Speaker 1: sickness