It woula sanoreir uudec

most experimental conaittons

the niuiine dose,

aredict viological effect.

Om

this assurztion,

multipliec by approximately 1.5 in orcer
of a yviven air dose from a

“point source”

obilateraily.

tne:

Furthermore,

sources

larce anical body

Lean yeenetry delivered

§

a:

However,

the

total

f

delivers

a

raziatiin

Situation iS teCtet

than by plene geometry.

the airtterence

ia aoserption of enersy

taroughout a

thus injury (in the letnal raaze) to the important tarr2t

the hernatopoletic stem cell,

Will regenerate.

which ceteraines whethec

the bone farr.~<

These eepth-dose curves are determined in uait density

using small Sievert charters

phantons.

thes

hn ar
shows depth-dose curves for siffercent types of radiation tz

provide an idea of

material

te

the

larpely at a prazing angle.

call,

their effects

‘1

spherically distributed

to conpare

r

to

Sivure 9

than dose

air dose value should be

o

is not identical either

approximated by solid

cather

in

the better cemmon parsueter in terns of wrich 2

eo

measuteu in air, would be

that

these circumstances ana

}-

clinic vor laboratory.

implanrea at 9 cm intervals

Y
The doses are @xprassea
aS percent of

Curve A represents

the

depth-dose curve

ecmmonly used energy of

in

tne

thie entrance air dose.

frye 250 «vp x ray.

radiation in aninel studies.

Note,

This

is a

the surcace

dese is #59uf 405 zgreater tran the entrances air dose and this talls off
very

ri iilv with Septna

an

lac

tlesue

4s

corresponcing to waa it woula be Su. of
target ceil,

the

regeneration.
bones,

Since

2000 <Yp x ray.
covalt-50 gamma

bene Marrow was
energy Geposites

factor.

The

cucvs

L

im the 1ici.--

tne entrance to the important

hemopotetic stem call,

the amceunt of

by a very larga

lant aporearuately

ich determines bone marrow

cistribeted
in

throuphout the bouy

tre henopoteric stem cell

Shows 2a

in 2:

vwsrie:

similar cepth-vose curve fur

Curve C is the initiil beth janma radiation and curve 2D is
radiation.

It Ls evizent

that tor

the

same air douse,

Jury to Reratopoletic stem cells scattered throughout the bone marrow
wacie.
lethal

sag ted

onsi erably and
dose

curves.

thus would be

expected

to result ia different

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