scholarly journals STUDIES ON X-RAY EFFECTS

1921 ◽  
Vol 33 (4) ◽  
pp. 433-439 ◽  
Author(s):  
Waro Nakahara ◽  
James B. Murphy
Keyword(s):  
The State ◽  
X Rays ◽  
X Ray ◽  
Small Doses ◽  
Ray Effects ◽  
Lymphoid Proliferation ◽  
Marked Suppression

Mice treated with small doses of x-rays and inoculated with cancer immediately afterwards, show a marked suppression of lymphoid proliferation. If, however, the cancer inoculation is made 7 days after the exposure to x-rays, thus permitting the primary lymphoid stimulation known to occur soon after the x-ray treatment to arise, a second stimulation takes place in a large proportion of mice thus inoculated. Changes in the blood of mice x-rayed and inoculated with cancer 7 days afterwards show that the state of resistance to cancer inoculation is attended by blood lymphocytosis, as is the case in all other varieties of immunity to transplanted cancer so far studied.

scholarly journals STUDIES ON X-RAY EFFECTS

1921 ◽  
Vol 33 (4) ◽  
pp. 429-432
Author(s):  
Waro Nakahara ◽  
James B. Murphy
Keyword(s):  
Lymphoid Tissue ◽  
X Rays ◽  
X Ray ◽  
Small Doses ◽  
Refractory State ◽  
Ray Effects

A relatively increased degree of resistance in mice to a certain strain of transplantable cancer was demonstrated after treatment of animals with small doses of x-rays capable of stimulating lymphoid tissue. The refractory state induced was determinable 3 to 7 days after the dose of x-rays was given.

scholarly journals STUDIES ON X-RAY EFFECTS

1922 ◽  
Vol 35 (4) ◽  
pp. 475-485 ◽  
Author(s):  
Waro Nakahara ◽  
James B. Murphy
Keyword(s):  
Small Dose ◽  
Biological Effect ◽  
Lymphoid Organs ◽  
X Rays ◽  
Thin Glass ◽  
X Ray ◽  
Spark Gap ◽  
Mitotic Figures ◽  
High Degree ◽  
Ray Effects

A study has been made of the biological effect of a small dose of soft x-rays given off by a special water-cooled tube with a window of thin glass, operated at ½ inch spark-gap and 11 milliamperes. Mice exposed for 1 minute show 2 days later in the blood an increase in the number of lymphocytes and in the lymphoid organs an increased number of mitotic figures. There occurs also a marked dilatation of the vessels of the suprarenals, particularly between the cortex and medulla. The latter condition did not appear until after 24 hours and was still present 14 days after the treatment. No change was detected in other organs. Mice treated in this way showed a high degree of resistance to cancer transplants. The amount of resistance varied with the time of the inoculation after the treatment. The resistance was not increased before 3 days after and was at its highest point 10 days after the treatment.

scholarly journals STUDIES ON THE MECHANISM OF ACTION OF IONIZING RADIATIONS

1952 ◽  
Vol 35 (6) ◽  
pp. 865-871 ◽  
Author(s):  
E. S. Guzman Barron ◽  
S. Louise Seki
Keyword(s):  
Cell Division ◽  
Sperm Cells ◽  
X Rays ◽  
Thiol Compounds ◽  
X Ray ◽  
Arbacia Punctulata ◽  
Inhibiting Effect ◽  
Small Doses ◽  
X Irradiation ◽  
Ionizing Radiations

On x-irradiation of the eggs and sperm of Arbacia punctulata there was inhibition of respiration with relatively large doses, whereas there was an increase with small doses. The dose required to produce an increase of respiration depended on the degree of sensitivity of the cell to the effect of ionizing radiation. Sperm cells were more sensitive; then came fertilized eggs; unfertilized eggs were the least sensitive. The inhibiting effect of x-rays on cell division was observed even on irradiation with x-ray doses which produced an increase of respiration. These results are compared to similar effects produced by thiol reagents and are attributed to oxidation of the thiol compounds in the cell.

scholarly journals STUDIES ON X-RAY EFFECTS

1920 ◽  
Vol 31 (1) ◽  
pp. 13-29 ◽  
Author(s):  
Waro Nakahara ◽  
James B. Murphy
Keyword(s):  
Lymphoid Tissue ◽  
Proliferative Activity ◽  
X Rays ◽  
X Ray ◽  
Lymph Glands ◽  
Spark Gap ◽  
Mitotic Figures ◽  
Ray Effects ◽  
Stimulation Of

A dose of x-rays governed by the following factors induces a stimulation of lymphoid tissue in mice: spark-gap ⅞ inch, milliamperage 25, distance 8 inches, time of exposure 10 minutes. Within 4 days after this dose there appeared an abnormally large number of mitotic figures in the lymphoid tissue of spleen and lymph glands, indicating an acceleration of the proliferative activity of the tissue.

scholarly journals Factors that Govern the Sensitivity of Oat Seed to X-rays

1969 ◽  
Vol 43 (3) ◽  
pp. 194-211
Author(s):  
C. L. González-Molina
Keyword(s):  
X Rays ◽  
Seedling Vigor ◽  
X Ray ◽  
Large Seed ◽  
Relative Damage ◽  
Small Seed ◽  
Series Of Experiments ◽  
Ray Effects ◽  
The Relationship ◽  
Proportional Decrease

A series of experiments was performed designed to determine the relationship between hull covering and seed and germ size to X-ray sensitivity of oat seed of three varieties: Mo. 0-205, Simcoe, and Bonham. The seed contained approximately 14 and 20 percent of moisture and X-ray dosages of 40,000 and 30,000 r were used. The data indicated that: 1. Hull-coverings may or may not afford protection to the seed from X-rays. Both varieties and moisture content produced differential reactions. 2. Large seed were more affected by high X-ray dosages than were small ones. Larger seed have larger germs, exposing more area to X-ray effects. A decrease of germination and seedling vigor was obtained when large seed were exposed to radiation, although there was no indication of a proportional decrease between germ size and relative damage to seedlings from large and small seed. 3. Germination percentages of oat-seed lots receiving up to 40,000 r of X-rays were as good as those of the checks, when measured on blotters in a plant germinator, but seedling vigor was materially reduced. Lowered germination percentages noted in greenhouse experiments were probably due to insufficient vigor to grow through the soil on the part of many seedlings. Probably all of the X-ray effects at the dosages used were caused by decreases in seedling vigor. 4. Radicals and plumules of the seed were equally damaged by X-ray treatment.

scholarly journals STUDIES ON X-RAY EFFECTS

1922 ◽  
Vol 35 (4) ◽  
pp. 487-492
Author(s):  
J. Heng Liu ◽  
Ernest Sturm ◽  
James B. Murphy
Keyword(s):  
Histological Examination ◽  
Subcutaneous Tissue ◽  
X Rays ◽  
Intact Skin ◽  
Exposed Area ◽  
X Ray ◽  
Lymphoid Infiltration ◽  
Ray Effects

An erythema dose of x-rays given direct to the exposed subcutaneous tissue and muscle greatly diminishes the susceptibility of the exposed area to transplanted cancer. The same dose given over the intact skin does not affect the resisting power of the underlying subcutaneous tissue. Histological examination shows that a few days after the exposure of the subcutaneous tissue there is a lymphoid infiltration of this tissue, which infiltration sometimes includes the muscle layers as well.

scholarly journals THE MECHANISMS OF X-RAY EFFECTS ON CELLS

1942 ◽  
Vol 25 (4) ◽  
pp. 533-537 ◽  
Author(s):  
Karl Sax
Keyword(s):  
Chromosomal Aberrations ◽  
Minor Importance ◽  
Physiological Effects ◽  
X Rays ◽  
Chromosomal Alterations ◽  
X Ray ◽  
Nuclear Cycle ◽  
Ray Effects

Irradiation of Tradescantia microspores does not increase subsequent sensitivity to x-rays as measured by the frequency of induced chromosomal aberrations curing the nuclear cycle. The slight decrease in sensitivity is to be expected because acentric fragments are less sensitive than the centric chromosomes. The physiological effects of x-rays appear to be of minor importance in causing injury or death of individual cells, and most of the deleterious effects can be attributed to "direct hits" which produce chromosomal alterations. In the reaction of tissues to x-rays the physiological effects may play a more important part.

scholarly journals STUDIES ON X-RAY EFFECTS

1919 ◽  
Vol 29 (1) ◽  
pp. 75-82 ◽  
Author(s):  
Marguerite M. Thomas ◽  
Herbert D. Taylor ◽  
William D. Witherbee
Keyword(s):  
The Other ◽  
X Rays ◽  
X Ray ◽  
Spark Gap ◽  
Before And After ◽  
Circulating Lymphocytes ◽  
Ray Effects

This study consists of blood counts on nine rabbits after an exposure to x-rays of a 7/8 inch spark-gap, milliamperage 25, distance from the target 8 inches, and time of exposure 20 minutes. In seven of the nine animals there resulted an increase of the circulating lymphocytes. In five of these the increase was marked and in two others definite but not striking. Of the two animals which showed no stimulation one showed marked fluctuation of counts both before and after x-rays and the other little or no change. The higher penetrating dose (6 inch spark-gap, milliamperage 5, distance from the target 10 inches, time 26 minutes and 57 seconds) given to two animals produced no appreciable stimulation.

scholarly journals ROENTGEN RAY INTOXICATION

1923 ◽  
Vol 38 (6) ◽  
pp. 725-730 ◽  
Author(s):  
S. L. Warren ◽  
G. H. Whipple
Keyword(s):  
Small Intestine ◽  
Single Dose ◽  
Cell Injury ◽  
Cumulative Effect ◽  
X Rays ◽  
Epithelial Injury ◽  
X Ray ◽  
Tumor Tissues ◽  
Small Doses ◽  
Repeated Doses

A single large dose of x-rays over the abdomen will cause a definite injury of the mucosa of the small intestine and the severity of the clinical intoxication seems to parallel this recognizable epithelial injury. This clinical intoxication lasts 4 to 6 days if the x-ray dose is sublethal. Subsequent doses of radiation given within this period of clinical intoxication give recognizable evidence of summation or a cumulative effect. Small but repeated doses of radiation given within a 5 or 6 day period will cause practically the same cell injury and clinical intoxication as will a single dose representing the sum of the small doses expressed in milliampere minutes. Doses of radiation given at 6 day or longer intervals show no evidence of summation. The reaction of this relatively sensitive intestinal epithelium to radiation may be similar to the reaction of certain deep lying tumor tissues to x-ray therapy and our experiments may give information of value to physicians concerned with x-ray or radium therapy.

scholarly journals STUDIES ON X-RAY EFFECTS

1919 ◽  
Vol 29 (1) ◽  
pp. 83-87 ◽  
Author(s):  
Waro Nakahara
Keyword(s):  
Small Dose ◽  
Lymphoid Tissue ◽  
X Rays ◽  
Destructive Effect ◽  
Slight Degree ◽  
X Ray ◽  
Lymph Glands ◽  
Ray Effects ◽  
Stimulation Of

1. The small dose of x-rays applied to the rabbit has no appreciable destructive effect on the lymphoid tissue. 2. Indications of stimulation of the lymphoid tissue appear immediately after the treatment, become most pronounced in 2 (in lymph glands) to 4 (in the spleen) days, and persist, in a slight degree, up to the 14th day. 3. These facts suggest that the lymphocytosis induced by the small dose of x-rays is due to a primary stimulative effect upon the lymphoid tissue of the animal.

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