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 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.

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 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 (3) ◽  
pp. 373-384 ◽  
Author(s):  
James B. Murphy ◽  
J. Heng Liu ◽  
Ernest Sturm
Keyword(s):  
Guinea Pigs ◽  
Normal Serum ◽  
Lymphoid Cells ◽  
Mitotic Figure ◽  
X Ray ◽  
Lymph Glands ◽  
Large Numbers ◽  
Mitotic Figures ◽  
Ray Effects

Lymphoid cells, prepared from the thymus and lymph glands of rats, when suspended in the serum of x-rayed rats and incubated for 2 hours, increase in number from 15 to 30 per cent, and mitotic figures are found among these cells in fairly large numbers. A like suspension of cells in normal serum undergoes rapid disintegration and in only one instance among a large number of films examined was a mitotic figure found. The stimulative effect of the serum from x-rayed rats endures from 1 to 2 hours after the exposure but is not detectable in the serum taken 17 hours or later after the treatment. Serum x-rayed in vitro is devoid of stimulative action. The lymphoid cells of rabbits and guinea pigs are so fragile as to make impossible the obtaining of counts accurate enough for experimental purposes. The serum of one species caused such rapid disintegration of the cells of another that it was impossible to determine the specificity of the reaction.

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 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.

INVESTIGATION OF HORMETIC STIMULATION IN STRAWBERRY PLANTS USING IONIZING RADIATION

1987 ◽  
Vol 67 (4) ◽  
pp. 1181-1192 ◽  
Author(s):  
S. C. SHEPPARD ◽  
C. L. GIBB ◽  
J. L. HAWKINS ◽  
W. R. REMPHREY
Keyword(s):  
Ionizing Radiation ◽  
Field Trials ◽  
Early Growth ◽  
Dominant Factor ◽  
X Rays ◽  
X Ray ◽  
Significant Stimulation ◽  
Low Levels ◽  
The Individual ◽  
Stimulation Of

Hormesis is the stimulation of growth by very low levels of inhibitors or stressors. This phenomenon may be useful in crops where the usual cultural factors have been optimized. The literature indicates that substantial stimulation of early growth of strawberries (Fragaria × ananassa) could be achieved by exposing transplants to low doses of ionizing radiation. Experiments were conducted to test the effectiveness and reliability of X rays as a hormetic agent. Plants of a day-neutral cultivar Hecker and of a June-bearing cultivar Glooscap were irradiated at 0.5–16 Gy and planted in pots. The plants were grown outdoors and growth was recorded each week. Significant stimulation above the controls in the number of trifoliate leaves occurred in the day-neutral cultivar. This effect persisted until the first phase of fruiting. No significant stimulatory effects were observed at any time in the June-bearing cultivar. Two field trials with a June-bearing cultivar Redcoat, irradiated at doses of 0.5 and 2 Gy, also revealed no significant stimulation. The dominant factor regulating early growth was the size of the individual transplants. Therefore, although hormetic stimulation may occur, it will be difficult to quantify and optimize and it will not likely be useful for practical application.Key words: X ray, transplant, day-neutral, June-bearing

An oscillographic study of the production of X-rays by a Coolidge tube

1924 ◽  
Vol 22 (1) ◽  
pp. 70-75 ◽  
Author(s):  
J. A. Crowther
Keyword(s):  
Measuring Instruments ◽  
X Rays ◽  
X Ray ◽  
Spark Gap ◽  
High Tension

Radiologists have often had cause to note certain apparent anomalies in the behaviour of their apparatus. It is quite well known that different X-ray tubes, excited by different kinds of high tension apparatus, yield X-radiation of markedly varying quality and quantity even under conditions which, as measured by spark gap and milliammeter (the usual measuring instruments of the radiologist), are apparently identical. These anomalies seemed to offer an interesting field for investigation, and one which might not be without value on the practical side.

scholarly journals On the X-ray technique of malignant tumors Brock (S’trahlentherapie. Bd. 13, № 1)

2021 ◽  
Vol 18 (2) ◽  
pp. 105-105
Author(s):  
V. G.
Keyword(s):  
Malignant Tumors ◽  
X Rays ◽  
X Ray ◽  
Lymph Glands

Analyzing this technique Brock (S'trahlentherapie. Bd. 13, No. 1) strongly points out the need for the corresponding lymph glands to be protected from the action of x-rays during the X-ray examination of malignant tumors.

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.

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