All issues
Volume 5, Issue 3-4
Displaying 1-7 of 7 articles from this issue
- |<
- <
- 1
- >
- >|
-
Shozo IBA, Noboru ARIMIZU, Hirotake KAKEHI1964 Volume 5 Issue 3-4 Pages 139-146
Published: 1964
Released on J-STAGE: August 29, 2006
JOURNAL FREE ACCESSMany of the patients of benign tumors and chronic inflammatory diseases treated by radiation are among the younger ages and their child expectancy is usualy high. If the patients are few in number, but the amount of gonadal exposure is considerably high in radiation treatment, much attention should be paid to reduce the gonad dose. Another gonadal exposure in radiation treatment may be considered for the attendant, who watches an infantile patient at close quarters and takes care of it not to move during the treatment.
The gonad dose in the conventional X-ray treatment was measured upon fifty patients of benign tumors and tuberculous cervical lymphadenitis and eighteen attendants of infantile patients of malignant tumor in recent two years at the Chiba University Hospital. Total gonad dose in one session of X-ray treatments was less than about 300 mr in most cases and more than 500 mr in a few cases.
Fundamental experiments were performed concerning the gonad dose. The scattered dose inside and outside the phantom was measured on various field sizes, filtration and kilovoltages. Measurements were made on phantoms using usual commercial pocket chambers and Philips Universal Dosemeter. Several procedures are discussed reducing the gonadal exposure of the attendants of infantile patients.View full abstractDownload PDF (273K) -
Satori HAYASHI, Takaya KITAO, Miyoko HAYASHI, Iwashiro OKI, Akira OSHI ...1964 Volume 5 Issue 3-4 Pages 147-158
Published: 1964
Released on J-STAGE: August 29, 2006
JOURNAL FREE ACCESSThe main sources of leakage X-rays from a color television receiver are a cathode ray tube and a shunt regulator valve, 6 BK 4. As to each radiation from these devices manufactured in Japan, observations were carried out on the energy distribution, the geometrical distribution, the dose rate level and its correlation to beam current or applied voltage. Radiations from completed television receivers were also investigated. The radiation levels from the both sources showed a significant difference among individual products. Then a method has been proposed to estimate the percentage of television receivers which should give leakage radiation beyond a certain dose rate level. It has been found that the shunt regulator valve gives a high level of leakage radiation and this should be shielded more cautiously than the cathode ray tube. It is rather easy to make the dose rate level below the maximum permissible limit by means of a simple shielding, for the radiation is mainly composed of very soft ccmponents.View full abstractDownload PDF (490K) -
Hiroaki FUNAOKA, Haruo EZAKI, Fumio ARAKI, Yoshio SUGIHARA1964 Volume 5 Issue 3-4 Pages 159-165
Published: 1964
Released on J-STAGE: August 29, 2006
JOURNAL FREE ACCESSSaline extracts from human gastric cancer divided into two parts, one of which was irradiated by X-ray of 2000 r, before homogenization, were fractionated with EtOH, in which S, was 30% vol. ppt., S, was 30-70% vol. ppt., and S3 was supernatant. Further, S1 and S2 were fractionated with (NH4)2SO4 into P1 (30% sat. ppt.), P2 (30-50% sat. ppt.), P3 (50-700/ sat. ppt.), and P4 (supernatant).
The S2P1 and S2P2 fractions non-irradiated inhibited the growth of subcutaneous solid Ehrlich ascites tumor in mice, which were respec tively significant at the level of 10% and 5%, but the same fractions irradiated lost the growth inhibitory activity.
The S2P3 fraction irradiated inhibited the growth of solid tumor at the level of 20%, and was different from the equivalent non-irradiated fraction having mitosis promoting activity at the significance of 0 .5%
These data may show that malignant tumor contains the growth inhibiting substance which is not species specific, and the carcinostatic effect of X-ray irradiation is due to the destruction of balance between growth promoting and inhibiting substances inside of the tumor tissue.View full abstractDownload PDF (258K) -
Fumio KAWAMURA, Jindo KOBAYASHI1964 Volume 5 Issue 3-4 Pages 166-171
Published: 1964
Released on J-STAGE: August 29, 2006
JOURNAL FREE ACCESSThe present study deals with cytological effects of 2-mercaptoethylamine on the Yoshida-sarcoma, the MTK-sarcoma III and Ehrlich ascites tumor concentrating a special attention on cell growth of tumor.
2-Mercaptoethylamine exerts influence upon tumor cells in process of mitosis, especially on an increase of mitotic cells, leading to increase of prophasic cells at first and metaphasic cells secondarily.
The protection mechanism against radiation exerted by 2-mercaptoethylamine indicated that this drug induced an increase of mitotic activity. This increase of mitotic activity might be interpreted as a protecting effect against radiation injury.View full abstractDownload PDF (208K) -
Miyoko HAYASHI, Satori HAYASHI1964 Volume 5 Issue 3-4 Pages 172-182
Published: 1964
Released on J-STAGE: August 29, 2006
JOURNAL FREE ACCESSIn order to determine the dose rate of X-rays having energies lower than 35 keV, a method that counting rate determined with a GMcounter was converted to dose rate was investigated. A radiation field of which intensity is near background can be measured by this method. Conversion coefficients from counting rate to dose rate were calculated as a function of photon energy for some GM-tubes available in Japan. The characteristics of the conversion coefficient were examined and the nature of GM-tube favorable for monitoring was discussed. By the proposed method a continuous X-ray field can be measured with a satisfactory accuracy and a precision of about 5%. The method can be applied to the determination of absorbed dose rate as well as exposure dose rate.View full abstractDownload PDF (425K) -
Masatoshi SEKI, Shigetaka SEKIYAMA, Tatsuo YONEYAMA1964 Volume 5 Issue 3-4 Pages 183-205
Published: 1964
Released on J-STAGE: August 29, 2006
JOURNAL FREE ACCESSElectron microscopic observations of the normal mouse spleen confirm the reticular cells having an important role on erythropoiesis and lymphocytopoiesis. The possibility of DNA reutilization is discussed in connection with phagocytic bodies (Phagosomes) which are derived from phagocytized nuclear substance.
A special lock-gate-like structure of the sinus wall is observed and it is considered that this makes possible to form blood channels between the pulp cord and sinus by an open-and-close mechanism depending upon the situation needed.
Comparing with the normal structure, the changes in the mice spleen after total body irradiation of 1, 000 r were studied, and the following results were obtained.
(1) Half an hour after the irradiation, the formation of clear foci is prominent in the nucleus, cytoplasma and mitochondrial matrix of the lymphocytes. As the time passes after irradiation, the clear foci in the cytoplasma disappear and focal aggregation of chromonema occurs, which tends to increase in its intensity. These changes are considered to be based on the alteration of molecular structure of the constituents caused by X-ray irradiation.
(2) Two hours after irradiation, the reticular cells adhere to the lymphocytes and by the activity of the former, the latter are dehydrated and condensed. In the next step, the condensed lymphocytes are phagocytized and digested by the reticular cells.Formation of the so-called tingible bodies seen histologically only occur when the reticular cells could participate in this phenomenon.
(3) In the red pulp, a part of the myeloid cell elements is phagocytized by the same mechanism of the reticular cells and other parts will flow out from pulp cord to sinus space through the opening of lock-gates of endothelial cells at the sinus wall.View full abstractDownload PDF (2686K) -
Yutaka NAGAYA, Masaru SHIOZAKI, Yoshio SETO1964 Volume 5 Issue 3-4 Pages 206-214
Published: 1964
Released on J-STAGE: August 29, 2006
JOURNAL FREE ACCESSSignificant increase of Ce-144 concentration was detected in the Indo-Antarctic surface sea water collected in early 1962 (mean 0.57 μμ/l), comparing with those of early 1961 (mean 0.12 μμc/l), and was supposed to be caused by the stratospheric fallout injected by the resumption of nuclear explosions by USSR on the northern polar region during September to November, 1961. On the other hand, no increase of Sr-90 concentration was detected in these samples (means 0.07 and 0.06 μμ/l) and that of Cs-137 concentration was slight (means 0.13 and 0.15 μμ/l).
The horizontal distributions of the radioactive nuclides in surface water indicate the decreasing Sr-90 and Cs-137 concentrations with increasing latitude, but no latitudinal variation of Ce-144 is detected.
By comparison of Ce-144 concentrations in early 1961 and 1962 samples, only 6 months of minimum time is estimated for the transport of stratospheric fallout debris from the northern polar region to the southern hemisphere, and this value is considerably shorter than those reported by other workers.View full abstractDownload PDF (361K)
- |<
- <
- 1
- >
- >|