The possibility of using238Pu UL X-ray source to particle size determination by X-ray transmission is investigated. The energy of UL X-rays emitted from238Pu by its internal conversion is suitable for the determination of powder materials of various atomic numbers. Since the X-rays are polychromatic, proportionality between logarithm of relative X-ray absorption, ln (Iw/I), and concentration of suspended powder in cell exists approximately in the range of low concentration. The experimental results obtained with the cell of 5 cm X-ray path length and the materials of various atomic numbers show that ln (Iw/I) less than 1.1 at initial uniform suspension would be applied to the determination on cumulative particle weight per cent with the systematic error less than 3%. By taking the initial suspension concentration of 4%, the determination could be applied to the materials of atomic number higher than that of Mg with the error, due to instrumental fluctuation, of less than 3%.
Use of holography for imaging of radioisotope distribution which was reported by Barrett, H.H. in 1972, has been marked as a new γ-ray imaging. Generally in optical fields holography was very used for record and processing of three dimensional image by coherent wave such as laser beam. But γ-rays are incoherent and do not condense by optical lenses. So it was needed that the hologram of incoherent sources was formed without optical lenses. The method recording shadow of on axis zone plate with Fresnel diffraction pattern was used for obtaining an incoherent hologram. This method has the advantages of the improvements of resolution and γ-ray detection efficiency, and also the constitution of this system is simple and economical. But the disadvantage is that the process consists of two steps forming holograms and reconstructing images. In this paper fundamental problems of γ-ray hologram and practicabilities for γ-ray imaging of this method were discussed. In our system medical X-ray films combinating with industrial intensifying screens were used as a detector and γ-ray shadow holograms were obtained during about 3 minutes. From the shadow hologram, images were reconstructed using parallel beam of the laser (He-Ne laser, single mode, 6328Å, 1 mW) . Zone plate was consisted of coaxial lead rings with 10 open zones. The aperture area of this zone plate collimator was more several hundreds times than the pinhole, so the detection efficiency of γ-rays was better. Using99mTc 10 mCi as γ-ray source, points, English characters and thyroid phantom were tried to imaging and these reconstructed images were shown. Image resolution 3-5 mm was obtained in the reconstructed image of object at distance 10 cm from the collimator.
The incorporation of65Zn into the eggs was investigated after a single or daily intraperitoneal administration to the laying Japanese quails. After a single intraperitoneal administration, the65Zn appeared first in the 2nd egg yolks, and reached the highest level in the 3rd and 4th ones, followed by a gradual decrease thereafter. The cumulative amount of65Zn in the egg yolks over a period of 3 weeks accounted for about 40% of the dose. After daily intraperitoneal administration, the 6th-9th egg yolks contained the highest radioactivity among the eggs examined. In addition, the whole-body retention patterns were also observed in the both trials.
Chinoform (5-chloro-7-iodo-8-quinolinol) -14C (302.4μCi/83 mg) packed in a capsule was given orally to a dog weighing 10.5 kg and urine and feces were collected for 5 days after dosing. The excretions of large portion of radioactivities in urine and feces were observed at the 1st day and 3rd day after dosing, respectively. The total radioactivity in both excreta in 5 days was about 70% of dose, and the urine was used for the study of metabolites. The urine was extracted with a mixture of benzene and pyridine (9: 1), and organic layer and aqueous layer were obtained. Intact chinoform and 5-chloro-8-quinolinol (a deiodinated product of chinoform) were identified in the organic layer by radiochromatography and isotope dilution method. From the water layer of urine, glucuronides of chinoform and the deiodinated product, and sulfate of chinoform were identified as the metabolites.
Problems on the determination of serum vitamin B12values using Phadebas B12test kit were studied. Various causes considered to influence the results were investigated. There was no release of bound57Co-B12from Sephadex-intrinsic factor complex. Standard curves which were expressed by percentages of each sample versus zero sample, were slightly different each other on their forms and inlines. Variations of percentage of zero samples showed the standard deviation of ±9.2% of mean value. Percentage of B/T in various concentration of B12showed also one standard deviations of 8-9%. There were no inhibitory effects on the /resence of serum in the sample to binding ability of B12to Sephadex-intrinsic factor complex. It was more suitable to use 0.5 ml of extracted dilution of serum did not change the measured B12values and standard curve was more accurate in lower side of B12concentration than in higher side. The reproducibility and recovery of serum B12values showed quite excellent results by this method. Phadebas B12test kit gave correct serum B12values in general without difficult techniques. Then it was concluded that Phadebas B12test kit was one of the most suitable method for the determination of serum B12values in clinical samples.
Two hundred and forty-one99mTc-pyrophosphate bone scannings of 181 patients with trauma were reviewed in comparison with the bone X-ray films taken in the same day. Bone scannings were obtained, 4 hours after injection of 10mGi of99mTc-pyrophosphate with a scintillation camera. Forty-seven of 51 fractures determined by X-ray study were detected by bone scanning. Initial radiographic studies missed 13 fractures-5 in the rib, 5 in the foot and 3 in the other portions, however, bone scanning detected correctly all of these fractures. Forty-four cases of positive bone scanning with the negative X-ray film's were found in this series. Although final diagnosis was not obtained in these cases, many of these bone scannings might reveal true positive, since abnormalities on the bone scanning could be produced by periosteal injuries alone. Bone scanning was very sensitive for picking up fractures in almost all portions of the body and especially useful for, detection of the fractures in such areas as rib, feet and hands which were frequently difficult to define by routine X-ray study. Bone scanning can eliminate false negative of the radiographic study in evaluation of trauma.
Using a newly developed whole body gamma scanner (Toshiba-RDA-601), we recorded the whole body bone scans in 5 patients (two normal, osteomalacia, bone metastases of prostate cancer and bone metastases of breast cancer), and compared the regular scintiscans with those of bird's-eye view images which were made with the data processor of the scanner. The scans were started about 2 hours after intravenous injection of 3 to 8 mCi of 99mTC-monofluorophosphate stannous fluoride. The recorded bird's-eye view scans displayed the skeletal system vividly as they were, and the distribution of radioactivity semiquantitatively. In conclusion the bird's-eye view scan is superior to the regular scan, in view of the point that it expresses the distribution of radioactivity semiquantitatively and enables us to know the amount of abnormally accumulated radioactivities by measuring the height of the peak of the diseased area, although this is very difficult in the regular scan. But at present we need more clinical studies in order to determine which is better in detecting abnormal part clinically.