E2
What is: dose of radiation that is delivered continuously but at a lower absorbed dose.
Protraction.
what dose is required to cause Cerebrovascular syndrome, and what is the cause of death?
5000 RAD. broken vessels leading to fluid in brain. multi system failure, failure to CNS and CVS.
what is recovery or death?
may recover within 2-3 months or result in death.
What is LD 50/30?
dose that produces death in 50% of subjects within 30 days.
What is a Chromatid?
1. one of the two identical threadlike strands into which a chromosome divides during cell division.
2. contains a double helix of DNA
What are the results of radiation damage to DNA?
cell death, malignant disease, genetic changes.
What are the 4 response stages?
1. prodromal syndrome
2. latent period
3. manifest illness
4. recovery or death
What is the Radiosensitivity of living tissue?
1. immature cells highly radiosensitive.
2. more generalized, not specified.
3. cells that divide more are more radiosensitive.
What is: multi-stage process effect produced by free radicals that are created by interaction of radiation with water molecules (radiolysis) in which cell death can occur?
Indirect effect.
What are the early tissue reactions?
1. erythema
2. intestinal disorders
3. desquamation
4. radiodermatitis
5. nausea
6. fatigue/fever
7. hair loss
8. blood disorders.
what are the forms of Acute Radiation Syndrome (ARS)?
1. hematopoietic
2. Gastrointestinal
3. cerebrovascular (full body dose)
what is prodromal syndrome?
acute clinical symptoms, occur within hours after exposure and continue up to 2 days.
What is: solitary atoms or a combination of atoms that behave as single entities and are chemically reactive as a result of the presence of unpaired valance electrons.
free radicals.
is Direct effect or Indirect more harmful?
Indirect effect.
what is the most radiosensitive molecule?
DNA
What dose is required to cause Hematopoietic syndrome, and what is the cause of death?
1-10 gray, infection or bleeding.
what is latent period?
last about a week. depending on amount of radiation, could lead to recovery or death.
Free radicals are_______, and caused by ________?
1. high unstable and reactive ions.
2. indirect effect.
Which effect is more likely to happen, and why?
Indirect effect, because our body is made up of 80% water.
What are the effects that radiation has on DNA?
1. single strand break (Common)
2. double strand break (difficult to repair).
3. Mutations
4. Cross linking.
what is the dose required to cause Gastrointestinal syndrome, and what is the cause of death?
6-10 gray. loss of fluid, high risk of infection, electrolyte imbalance.
what is manifest illness?
moves into hematopoietic syndrome, affects blood system.
What is: biologic damage that occurs as a result of ionization of atoms on essential molecules which may cause molecules to become inactive or functionally altered. Photon hits DNA directly and potentially causes damage.
Direct Effect.
What is: giving a dose with time in between to recover?
Fractionation.
What is the target molecule?
DNA