LRA-215 Review Flashcards
___________ is defined as a branch of medical science that deals with the incidence, distribution, and control of disease in a population?
epidemiology
__________ describes radiation damage that increases the probability of causing a late effect but will not increase the severity of the effect?
stochastic
Radiation-induced lung cancer follows which dose-response relationship?
Linear; nonthreshold
Radiation-induced thyroid cancer is judged to be
linear ; nonthreshold
Radiation-induced lung cancer follows which dose-response relationship?
Linear ; nonthreshold
Relative risk is _________________.
observed cases / expected cases
The most radiosensitive period during pregnancy for radiation induced congenital abnormalities is during the ____________________.
first trimester
A __________ effect increases in incidence but not severity as the dose increases
stochastic
Studies of A-bomb survivors indicate that leukemia has a ______________________ dose-response relationship to radiation.
linear; nontreshold
The most radiosensitive cells in the hematopoietic system of the human body are the _________________.
lymphocytes
Immediately following a whole body dose of high levels of radiation the victim would experience (a) _____________________.
prodromal symptoms
The LD50/60 for humans of approximately 3.5 Gy. This refers to the concept that
50% of the population to be killed in 60 days
During the latent period, the radiation victim experiences _____________.
no symptoms
The minimum dose lethal to humans is 2 Gy to the whole body. This is concept known as
threshold
What would be the most likely immediate response to a whole body dose of 2 Gy
diarrhea, nausea, and vomiting
Death from acute radiation exposure follows a __________________ dose-response relationship.
nonlinear; threshold
A single chromosome aberration represents _____________ to the DNA within the chromosome.
severe damage
The central nervous system syndrome occurs following a whole body dose of 50 Gy or more. The chance for a full recovery is
impossible
About half of the population will experience skin erythema following a localized dose of 5 Gy. This is known as
skin erythema deterministic
The law of _________________ states that the radiosensitivity of living tissue is a function of the metabolism and maturation of that tissue.
Bergonie and Tribondeau
Tissue is _______ radiosensitive under high oxygen conditions and _________ radiosensitive under hypoxic conditions.
most; least
_______ is a measure of the capacity of a specific ionizing radiation to produce a specific biological effect, expressed relative to a reference radiation, such as radium, gamma rays or 250 keV X-rays.
relative biologic effectiveness (RBE)
The dose of radiation required per generation to double the spontaneous mutation rate is the definition of
doubling dose
_____ is an average calculated from the gonadal dose received by the entire population.
geneticaly significant dose (GSD)
The annual effective limit for the fetus of an occupational worker is
0.5 rem (5 mSv)
Which is the following is not an early response to radiation?
Breast cancer
Which of the following is not an acute local tissue effect of radiation exposure?
cataracts
When does the greatest radiation hazard to a fetus exist?
1st trimester
What is the annual occupational exposure limit?
50 mSv
Order the response stages to Acute Radiation Syndrome in order from 1st symptom to last.
- Prodromal
- Latent
- Manifest
- Recovery or death
What is a graphical representation of the relationship between radiation dose and observed dose, in which any dose may have a potential effect, and there is a direct relationship between dose and effect?
Linear dose-response curve
