Ch 8,9 Flashcards
Which type of curve is used for most types of cancers?
A linear nonthreshold (LNT)
The curve used for low level radiation(non cancer inducing) is
Linear-quadratic nonthreshold (LQNT)
Late tissue reactions may be demonstrated on which type of curve?
Linear Threshokd (LT)
Stochastic effects are what type of biologic damage?
Genetic mutations
Cancer
Effects that have no threshold; they occur more months or years after exposure are called
Stochastic effects
Biologic effects that occur soon after exposure of ionizing radiation are referred to as
Early effects
Cell killing and are directly related to dose of radiation received
Somatic tissue reactions
4 stages of ARS:
Prodromal, latent period, manifest illness, and recovery/death
Lethal Dose of Gray
LD 50/30
Will Kill 50% of people in 30 days.
Estimated 3-4 gy w/out medical support
90% of radiation induced damage may be repaired; ______ is irreparable.
10%
Mapping of chromosomes
This is done at what phase??
Karyotyping
Metaphase
Radiation doses of ____ will depress sperm and also delay menstruation
0.1 Gy
A single dose of —
2 Gy
The most radiosensitive follicles and least radiosensitive.
Intermediate
Small
In th hematopoietic system, cells all develop from a single precursor : called
The pluripotential stem cell
Study of cell genetics with emphasis on cell chromosomes
Cytogenetics
Shedding of outer layer of skin
Hair loss also called alopecia
Desquamation
Epilation
Skin diseases such as ringworm, used to be treated with irradiation the area with
Grenz rays (range from 10-20kvp)
Hematopoietic occurs at which dose of grays?
And death will occur at what amount of time?
1-10gray
6-8 weeks
Cerebrovascular syndrome occurs at what dose of gray??
How soon does d drug occur?
50gy or more
2-3hrs TO 2-3days
Causes fluid leakage in the brain
GI syndrome occurs at what dose of gray??
A patient may die how soon after?
6-10Gy
3-10days
Late tissue reactants are
Cataracts
Non random
Stochastic effects are??
Genetic mutations
Cancer
Somatic effects are:
Late tissue effects
Stochastic effects
Repair and recovery of cells are ____% irreparable. And the cells that are _________ are easier to repair themselves but destroyed more.
10
Easier
Early tissue reactions result in what? Within minutes, hours, days after exposure??
Cell death!
Early tissue reactions is also known as??
Acute radiation syndrome (ARS)
Exposure of 6gy or more
Atrophy is?
Organ shrinkage/cell death
3 layers of skin
Epidermis (outer)
Dermis(middle)
Hypodermis (subcaneous)
Skeletal abnormalities most frequently occur at how many weeks of conception?
3-20weeks
Congenital abnormalities occurs at what conception?
10days to 12 weeks
For humans the double dose is estimated to have a value of ;
1.56Sv
Forecasts that a specific # of malignancies will occur as a result of over exposure
Absolute Risk model
Predicts # of excess cancers will increase as natural incidence increases
Relative risk model
A late tissue reaction that is not random?
Cataracts
The gas that manatee through tiny gaps in the rocks that was a hazard for uranium mine workers?
Radon
Group of female who provide strong evidence that ionizing radiation causes breastfeeding cancer?
Th female women of atomic bomb in Japan
Genetic mutations at the molecular level?
Point mutations
Mutations expressed in offspring ?
Mutations not expressed in generative?
Dominant mutations
Recessive mutations
Production or origin of cancer
Carcinogenesis
Measures ionizing radiation in causes mutations ?
Doubling dose
Most radiation induced genetic mutations are
Recessive mutations
*Both parents need same genetic defects
