Biomaterial Database

Demonstration of a biological effect of natural ionizing radiations. 1983

A Conter, and D Dupouy, and H Planel

The blue-green alga, Synechococcus lividus, was grown under various levels of radiations. Shielding of cultures with lead resulted in a lower cell growth rate: the reduction disappeared when a normal radiation level was restored in the lead chamber. Irradiations from a thorium source at a dose-rate 14 times higher than that of natural irradiation stimulated the growth of the algae. These results are a new demonstration of a biological effect of background radiations.

UI	MeSH Term	Description	Entries
D004307	Dose-Response Relationship, Radiation	The relationship between the dose of administered radiation and the response of the organism or tissue to the radiation.	Dose Response Relationship, Radiation,Dose-Response Relationships, Radiation,Radiation Dose-Response Relationship,Radiation Dose-Response Relationships,Relationship, Radiation Dose-Response,Relationships, Radiation Dose-Response
D000458	Cyanobacteria	A phylum of oxygenic photosynthetic bacteria comprised of unicellular to multicellular bacteria possessing CHLOROPHYLL a and carrying out oxygenic PHOTOSYNTHESIS. Cyanobacteria are the only known organisms capable of fixing both CARBON DIOXIDE (in the presence of light) and NITROGEN. Cell morphology can include nitrogen-fixing heterocysts and/or resting cells called akinetes. Formerly called blue-green algae, cyanobacteria were traditionally treated as ALGAE.	Algae, Blue-Green,Blue-Green Bacteria,Cyanophyceae,Algae, Blue Green,Bacteria, Blue Green,Bacteria, Blue-Green,Blue Green Algae,Blue Green Bacteria,Blue-Green Algae
D001417	Background Radiation	Radiation from sources other than the source of interest. It is due to cosmic rays and natural radioactivity in the environment.	Natural Radiation,Radiation, Background,Radiation, Natural,Background Radiations,Natural Radiations,Radiations, Background,Radiations, Natural
D013910	Thorium	A radioactive element of the actinide series of metals. It has an atomic symbol Th, atomic number 90, and atomic weight 232.04. It is used as fuel in nuclear reactors to produce fissionable uranium isotopes. Because of its radioopacity, various thorium compounds are used to facilitate visualization in roentgenography.