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ionizing radiation, it also has e most remarkable regenerative and
reparative capacity.
It takes doses of well over a thousand roentgens
to permanently damage the gut in most mammals studied, and it is capable
of rapid, dramatic recovery of anatomical and functional integrity with
doses in the lethal range.”
.
10
Evaluating the data fram dogs exposed to
whole-body X-radiation the authors said, "--- it is suggested that doses
of approximately 1,100 to 1,500 r may represent the upper limit of the
possible efficacy of supportive measures in the treatment of the syndrome
of acute radiation injury.
With greater doses the damage to the in-
testinal mucosa appears irreparable and of an extent incompatible with
lite ."+ At the same time, it has been repeatedly indicated that the
‘irradiation of the gastrointestinal tract plays a major role in gross
whole-body effects associated with beady221324h21316, 17,18, 19
In fact one author“summarizes several experimental findings, "In
producing acute intestinal radiation death, irradiation of any major
portion of the exteriorized small intestine alone is almost equivalent
to whole-body irradiation---."
Graph Five suggests that the large
intestine may receive significantly greater doses than the small intestine
or stomach, and available data does not make clear what would be the
whole~body effects versus doses delivered in such ratios.
Most of these
experiments deal with the more violent criteria of death, but they do
suggest that the major contributory factor to recognized whole-body
effects such as nausea and vomiting associated with whole-body exposures
of 100-200 roentgens, may be the result of the gastrointestinal reaction.
This, then further suggests that Beveral hundred rads to the lower liarge
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