week 11 xray

Question 1

bergonie and tribondeau

Answer 1

metabolism, maturation and differention will govern which cells are more or less radiosensitive

Question 2

physical factor of linear transfer function

Answer 2

the rate at which energy is transfered through the matter it is going through and it loses energy

Question 3

units of linear energy transfer

Answer 3

keV/micrometer

Question 4

how much energy is being loss per unit distance is defined as

Answer 4

linear energy transfer function

Question 5

REB stands for

Answer 5

Relative biological effectiveness

Question 6

REB is expressed in terms of?

Answer 6

comparison between a “standard” radiation type and some other type of ionizing radiation

Question 7

fractionation is defined as?

Answer 7

breaking the total dose into smaller individual doses separated in time.

Question 8

radio sensitivity physical factors?

Answer 8

fractionation
LET
Protraction

Question 9

Protraction is defined as?

Answer 9

the total dose is continuously administered over an extended the time period

Question 10

Both fractionation and protraction can reduce the biological effects of ionizing radiation- why?

Answer 10

Because cells can repair radiation damage

Question 11

early effects of radiation

Answer 11

Effect manifests within minutes to days of exposure

Question 12

Late =

Answer 12

Effect manifests in months to years

Question 13

biologic effect:

Answer 13

oxygen effect and age
Radiosensitizing and radioprotective agents have been identified
Radiosensitizing agents

Question 14

Oxygen effect

Answer 14

Increased oxygenation increases radiosensitivity of tissues

Oxygen effect is LET dependent- there is more oxygenation effect for low LET radiation.

Question 15

Age biological effects

Answer 15

Sensitivity is greatest in utero birth and decreases until age 30; levels off and increases again in advanced age

Question 16

dose response relationships

Answer 16

how much radiation vs how much response was observed

Question 17

how can a dose response relationship be described as

Answer 17

linear vs non-linear

Question 18

threshold vs nonthreshold relationship is used to describe what about the dose response relationship

Answer 18

place where something starts at a particular set of dose and the nonthreshold is a a response when any amount of dose is given

Question 19

ambient level of response

Answer 19

means level of response present without or prior to any intervention

Question 20

will a curve that goes in to the ambient level be easy to see or hard to see?

Answer 20

hard

Question 21

the government uses radiation safety guidelines and estimating the biological effects of radiation

Answer 21

a linear, non-threshold dose-response model is used.

Question 22

most important macromolecule for radiation exposure?

Answer 22

DNA

Question 23

3 main radiation effects on macromolecules

Answer 23

breaking of main chain
crosslinking
point linking

Question 24

Cross-linking

defined as?

Answer 24

Formation of new chemical bonds that link side-chains with one another

Question 25

crosslinking results in

Answer 25

Results in increased viscosity of a macromolecular solution

Question 26

point lesion is defined as?

Answer 26

Disruption or alteration of single chemical bonds | Changes in the cell may be undetectable to the repair mechanisms of the intracellular environment.

Question 27

DNA and irradiation- 3 effects

Answer 27

Cell death Malignant disease Genetic damage

Question 28

Most likely molecule to interact with a photon is ____?

Answer 28

water

Question 29

Free radicals are

Answer 29

uncharged, highly reactive molecules or atoms with a single electron in their outer valence orbital.

Question 30

____________ also result from combination of free radicals- this is an important component of radiation cell damage

Answer 30

Toxic substances

Question 31

is it the indirect or the direct mechanism that has an effect on humans?

Answer 31

indirect

Question 32

ALARA?

Answer 32

as little as reasonably possible

Question 33

All ______ effects, and most normal tissue _____effects are deterministic.

Answer 33

early, late

Question 34

Deterministic effects are characterized by

Answer 34

A threshold dose below which no effect is seen | Worsening of the effect as dose increases over the threshold

Question 35

Stochastic effects account for the remaining _____ effects

Answer 35

late

Question 36

does stochastic effects have a threshold for dose?

Answer 36

no

Question 37

is the severity of the effects of radiation dose related?

Answer 37

no

Question 38

Stochastic effects include

Answer 38

radiation carcinogenesis and hereditary effects.

Question 39

Stochastic Effects expressed as?

Answer 39

statistically/ likelyhoods

Question 40

early effects of radiation

Answer 40

Acute Radiation Syndrome Local tissue damage Cytogenetic damage

Question 41

Acute Radiation Syndrome

Answer 41

Hematologic effects Gastrointestinal effects Central Nervous system effects

Question 42

Local tissue damage

Answer 42

Skin Gonads Extremities

Question 43

Cytogenetic damage

Answer 43

Observable with DNA analysis

Question 44

Late Effects

Answer 44

Leukemia Other malignant disease Local tissue damage Decreased life span Genetic Damage

Question 45

In utero radiation effects

Answer 45

Prenatal death Neonatal death Congenital malformation Childhood malignancy Decreased growth and developmento

Question 46

early effects general consept of body area and radiation intensity?

Answer 46

For a given level of radiation intensity, the larger the body area exposed, the greater the effect

Question 47

prodromal syndrome and a latent period is seen in

Answer 47

acute radiation syndrome.. which signifies that more symptoms are coming

Question 48

Prodromal period/ Prodromal syndrome | occurs at doses

Answer 48

>100 rads whole body

Question 49

s/s of Prodromal period/ Prodromal syndrome

Answer 49

diarrhea, nausea, vomiting, Leucopenia | Followed quickly by manifest ARS if dose is high

Question 50

Latent period may follow the prodrome

Answer 50

A period of relative recovery from prodromal symptoms | May last from hours to weeks

Question 51

blood count changes as what rem?

Answer 51

50

Question 52

vomitng occurs at twhat rem?

Answer 52

100

Question 53

mortality dose

Answer 53

150 rem

Question 54

LD

Answer 54

320-360

Question 55

100% mortality

Answer 55

800 rem

Question 56

the LD 50/60 is defined as

Answer 56

the dose at thiwch 50% the exposed pop. will die within 60 days

Question 57

for human beings the LD 50/60 is estimated at_____ rads whole body exposure

Answer 57

350

Question 58

early effects on local tissue

Answer 58

Erythema Epilation Desquamation

Question 59

what can happen to the reproductive organs of male around 10 rads

Answer 59

sterility

Question 60

at what level is sterility is temporary?

Answer 60

200

Question 61

at what level is sterility is permenant?

Answer 61

500 rads