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

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.

1919 ◽  
Vol 29 (1) ◽  
pp. 53-73 ◽  
Author(s):  
Herbert D. Taylor ◽  
William D. Witherbee ◽  
James B. Murphy

1. X-rays in large doses affect the lymphocytes before any of the other circulating cells. 2. There is a sharp fall in the total number of circulating lymphocytes, which is complete 48 hours after x-ray treatment. 3. Following the immediate decrease in the circulating lymphocytes there is a primary rise, followed by another fall, which in turn is followed by a permanent rise of these cells to normal. 4. The effect of the x-rays on different species of animals varies considerably, but in those studied, cat, monkey, guinea pig, rabbit, rat, mouse, and pony, the selective action on the lymphocytes was in all instances apparent. 5. When several animals of the same species are given the same dose of x-rays, the effect on the circulating lymphocytes seems to be quantitatively parallel, when determined by blood counts. 6. The polymorphonuclear neutrophilic leucocytes, when affected at all, increase in number immediately after the administration of the x-rays and then tend to decrease below their normal level. This decrease is followed by a return to normal many days before the lymphocytes reach their original level. 7. The other cells of the blood follow the neutrophilic curve. 8. Percentage figures, as determined by differential blood counts, do not give an accurate indication of the effect of the x-rays. It is only when these are multiplied by the total white blood count that a figure, representing the total number of cells of the series per c. mm. of blood, is obtained, which varies to the stimulus in a constant manner, the variations being practically quantitative.


1922 ◽  
Vol 35 (4) ◽  
pp. 475-485 ◽  
Author(s):  
Waro Nakahara ◽  
James B. Murphy

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.


1920 ◽  
Vol 31 (1) ◽  
pp. 13-29 ◽  
Author(s):  
Waro Nakahara ◽  
James B. Murphy

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.


2002 ◽  
Vol 09 (01) ◽  
pp. 401-405
Author(s):  
TAKESHI KANASHIMA ◽  
MASANORI OKUYAMA ◽  
HIROAKI OKAMOTO ◽  
KIMINORI HATTORI ◽  
HARUHIKO OHASHI ◽  
...  

High-flux soft-X-ray irradiation effects were investigated for the thick a-Si:H and μc-Si:H films, glass, MgF 2 and CaF 2 plates. The a-Si:H film of 7500 nm thickness has been burst, and its broken fragments flew off within several seconds. From the changes of Raman spectra before and after the irradiation and the film thickness dependence, it is thought that this is caused by rapid crystallization. SR-induced etching of glass, MgF 2 and CaF 2 plates has been observed. Photon energy dependence of the etching depth has been found. Exciting the Si K-shell is effective for etching the glass substrate. On the other hand, photon flux is important in the case of fluoride, and the maximum etching rate of CaF 2 is more than 1 μm/min.


1921 ◽  
Vol 33 (4) ◽  
pp. 433-439 ◽  
Author(s):  
Waro Nakahara ◽  
James B. Murphy

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.


1993 ◽  
Vol 21 (02) ◽  
pp. 187-195 ◽  
Author(s):  
Hsue-yin Hsu ◽  
Yau-hui Ho ◽  
Shi-Iong Lian ◽  
Chun-ching Lin

Six to seven week old male mice of ICR strain were exposed to different doses of x-rays to determine if Jen-Sheng-Yang-Yung-Tang could be a modifier in the elimination of radiation damage. Colony forming units of bone marrow cells in the spleen (CFUs) were measured before and after x-ray irradiation with intraperitoneal injection of 10 mg/20 g or 20 mg/20 g body weight of Jen-Sheng-Yang-Yung-Tang, once a day for seven consecutive days. The recovery of CFUs and hemocytes counts by 4 Gy irradiation with Jen-Sheng-Yang-Yung-Tang administration was faster for a concentration of 20 mg/20 g than 10 mg/20 g. The measurement of 10-day CFUs showed an increase of radiotolerance in the treatment of 20 mg/20 g administration before x-ray irradiation. The injection of Jen-Sheng-Yang-Yung-Tang accelerated the recovery of hemocyte counts in mice irradiated with 4 Gy x-ray; the effect was especially profound for leukocytes with 20 mg/20 g Jen-Sheng-Yang-Yung-Tang administration after irradiation.


1992 ◽  
Vol 2 (2) ◽  
pp. 43-46
Author(s):  
U. Fusco ◽  
R. Capelli ◽  
A. Avai ◽  
M. Gerundini ◽  
L. Colombini ◽  
...  

Between 1980 and 1987 we have implanted 46 isoelastic cementless THR in 40 patients affected with rheumatoid arthritis. We have reviewed 38 hips clinically and by X-ray. The mean follow-up was 8,5 years. Harris hip scores ranged from 30.6 preoperatively to 73,4 post-operatively when reviewed. While on the other hand Merle D'Aubigné hip scores ranged from 7,06 pre-operatively to 15,59 post-operatively. All patients have been satisfied, and X-rays showed an improvement for both Charnely and Gruen X-ray score.


1931 ◽  
Vol 53 (3) ◽  
pp. 405-411 ◽  
Author(s):  
James A. Hawkins

Areas on the abdomen of the same guinea pig were exposed to suberythemal doses of soft X-rays, to heat of an intensity below the critical dose for the production of burns, and to both radiations in sequence with various time intervals between the exposures. The only effect of exposure to X-ray or heat alone was a slight scaling of the skin. The areas exposed to heat and X-radiation developed well-marked and persistent burns when the exposure to one agent was made within 3 hours of the other. Scaling of the skin developed when the exposure to one agent was made 1 day after the other. This scaling was more marked and lasted longer than the scaling produced by either agent alone. The results were the same no matter in which sequence the agents were applied.


Author(s):  
J. A. Crowther

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.


2020 ◽  
Vol 497 (3) ◽  
pp. 3234-3250 ◽  
Author(s):  
Diego A Farias ◽  
Alejandro Clocchiatti ◽  
Tyrone E Woods ◽  
Armin Rest

ABSTRACT Supersoft X-rays sources (SSSs) have been proposed as potential Type Ia supernova (SN Ia) progenitors. If such objects are indeed persistently X-ray luminous and embedded in sufficiently dense interstellar medium (ISM), they will be surrounded by extended nebular emission. These nebulae should persist even long after an SN Ia explosion, due to the long recombination and cooling times involved. With this in mind, we searched for nebular [O iii] emission around four SSSs and three SNRs in the Large Magellanic Cloud, using the 6.5-m Baade telescope at Las Campanas Observatory and the imacs camera. We confirm that, out of the four SSS candidates, only CAL 83 can be associated with an [O iii] nebula. The [O iii] luminosity for the other objects is constrained to ≲17 per cent of that of CAL 83 at 6.8 pc from the central source. Models computed with the photoionization code cloudy indicate that either the ISM densities in the environments of CAL 87, RX J0550.0-7151, and RX J0513.9-6951 must be significantly lower than surrounding CAL 83 or the average X-ray luminosities of these sources over the last ≲10  000 yr must be significantly lower than presently observed, in order to be consistent with the observed luminosity upper limits. For the three SNRs we consider (all with ages <1000 yr), our [O iii] flux measurements together with the known surrounding ISM densities strongly constrain the ionizing luminosity of their progenitors in the last several thousand years, independent of the progenitor channel.


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