RADIOISOTOPES
Online ISSN : 1884-4111
Print ISSN : 0033-8303
ISSN-L : 0033-8303
Volume 26 , Issue 9
Showing 1-14 articles out of 14 articles from the selected issue
  • Nobuo FUKUDA, Toru MATSUMOTO
    1977 Volume 26 Issue 9 Pages 597-601
    Published: September 15, 1977
    Released: September 07, 2010
    JOURNALS FREE ACCESS
    Sequential data obtained in the tracer kinetic study is usually expressed by a sum of decaying exponentials q (t) = pΣi=1 Ai exp (-αit) . In this study propagation of the Poissonian fluctuation of radioactivity to the fluactuation of parameters a and A was discussed by using the Fisher's information matrix and the Cramér-Rao's inequality. Thus the effect of the variations of temporal sampling interval and of total observation time on the coefficient of variations for parameters a and A were investigated.
    The increased coefficient of variations due to the super-shortlife of radionuclide was also discussed.
    A fundamental theorem relevant to the functional imaging was observed, which states that the coefficient of variations of parameters are inversely proportional to square root of the administered tracer dose.
    Hence, S/N ratio given by the inverse of the coefficient of variation for each pixel of N×N-partitioned image is one N-th of that of the total kinetic parameters provided that the kinetics is spatially uniform. Then the information capacity on each pixel was defined. Finally, an analytical expression of the optimal number of the partition maximizing the total information capacity given by N2 times the information capacity of each pixel was derived.
    These theories were successfully applied to the 133Xe washout curves from lung.
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  • Atsushi ANDO, Hirofumi MORI, Itsuko ANDO, Tatsunosuke HIRAKI, Kinichi ...
    1977 Volume 26 Issue 9 Pages 602-605
    Published: September 15, 1977
    Released: September 07, 2010
    JOURNALS FREE ACCESS
    For purpose of the estimation of the radiation dose to humans from 169Yb-citrate, the whole-body retention studies using five rats were carried out. Following intravenous administration of 169Yb-citrate, the whole-body activity was monitored for 40 days by the animal counter. The whole-body retention curve consisted of three components: the first with a 3.6 hours effective half-time, the second with an 154 hours effective half-time and the third with a 29.9 days effective half-time. Therefore it was assumed that 32% of the administered 169Yb-citrate clears from the kidney with a short biologic half-time (3.6 hours), 18% remains in the liver and other soft tissues with a relatively long biologic half-time (194 hours) and 50% remains in the bone with a long biologic half-time (850 days) . Based on these biological data and the MIRD Committee method, the average dose to the bone and whole-body were 20.8 rads/mCi and 4.5 rads/mCi respectively.
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  • Hiroshi SHIONOIRI, Kiyoshi KONDO, Susumu UNEDA, Eiji GOTO, Yoshimi ONO ...
    1977 Volume 26 Issue 9 Pages 606-612
    Published: September 15, 1977
    Released: September 07, 2010
    JOURNALS FREE ACCESS
    ECF (extracellular fluid volume) was measured by 35S-sodium sulfate and at the same time value of PV (plasma volume) was determined by 131I-RISA in each subject.
    In normal ECF was an average of 181 ml/kg, 6.21 l/m2 and PV was 49.1 ml/kg, 1.69 l/m2. Both values o f ECF and PV in essential hypertension were almost the same as those in normal. In congestive heart failure ECF was 232 ml/kg, 7. 51 l/m2 and PV was 55.8 ml/kg, 1.80 l/m2
    In the patients with ascites or edema, ECF was 256 ml/kg, 8.69 l/m2 and PV was 53.0 ml/kg, 1.79 l/m2.
    The results of the measurement by the two compounds also corresponded to the conditions of the patients who showed electrolytes disorders (ACTH deficiency, SIADH) and was improved by treatment.
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  • Tadashige FUJII, Hisakata KANAI, Kenjiro HANDA, Shozo KUSAMA, Masaomi ...
    1977 Volume 26 Issue 9 Pages 613-618
    Published: September 15, 1977
    Released: September 07, 2010
    JOURNALS FREE ACCESS
    The dual radioisotope techniques with 197HgCl2 and other radionuclides were carried out using a scintillation camera coupling to a small digital computer. The joint use of tumor imaging, blood pool imaging and/or perfusion imaging was performed for the diagnosis of various lung diseases, and the superimposition image with 197HgCl2 and 99mTc-MAA or 99mTc-HSA (human serum albumin) was obtained to improve anatomic orientation of the radionuclide images. The positional pulses from the scintillation camera were fed into 4090 words memory through matrix input controller, and transferred from computer to magnetic tape recorder.
    Matrix images of the tape recorder were fed into small digital computer. The tumor image was obtained using 197HgCl2, and patient remaining the same position was given 99mTc-HSA for blood pool imaging and/or 99mTc-MAA for perfusion imaging. These images were displayed as smoothed image with 25 point weighted average, and the subtraction image with 197HgCl2 and 99mTc-HSA was obtained, too.
    The image as a iso-count map extracted out of the image of 99mTc-MAA or 99mTc-HSA was superimposed to the brightness image of 197HgCl2 or the subtraction image. These procedures were useful not only to improve anatomic orientation of the image but also to make isotope diagnosis of various lung diseases more reliable.
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  • Atsushi ANDO, Kenji DOISHITA, Sigeru SANADA, Itsuko ANDO, Hirofumi MOR ...
    1977 Volume 26 Issue 9 Pages 619-623
    Published: September 15, 1977
    Released: September 07, 2010
    JOURNALS FREE ACCESS
    Serial macroautoradiograms were obtained to determine the distribution of 203Hg-chlormerodrin, 203Hg-nitrate and 99mTc-DMSA in kidney. In the study, normal rats were used and these three radiopharmaceuticals were injected intravenously.
    Initial images of 203Hg-chlormerodrin showed the accumulation in the outer cortex, but no significant radioactivity in the medullary. On the other hand, delayed images revealed radioactivity shifting in concentration from the outer cortex to the inner cortex. Distribution pattern of 203Hg-nitrate was similar to that of 203Hg-chlormerodrin. In contrast to 203Hg-chlormerodrin and 203Hg-nitrate, 99mTc-DMSA was retained in the outer cortex without temporal changes in the distribution.
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  • Hisato MAEDA, Tsuyoshi NAKAGAWA, Nobuo YAMAGUCHI, Mitsuo TAGUCHI, Gisu ...
    1977 Volume 26 Issue 9 Pages 624-629
    Published: September 15, 1977
    Released: December 13, 2010
    JOURNALS FREE ACCESS
    The purpose of this presentation is to investigate computer processing techniques in brain functional imaging of regional cerebral blood flow (rCBFinitial) based on the initial slope method using 133Xe.
    The joint camera-computer system used in this study consists of the GCA-202 scinticamera and the DAP-5000N computer system. Following the internal carotid arterial injection of 3-5 mCi of 133Xe, 5 second frames of data in a 64×64 matrix form were acquired for a period of 14.5 minutes utilizing the on-line computer system.
    Automatic computation of rCBFinitial and its relative standard deviation (RSD), was done for the washout curve in each element of the matrix.
    In view of the rCBFinitial value, the statistical error and the spatial resolution, the optimum conditions for rCBFinitial functional imaging were concluded as follows,
    1. Time interval 10 seconds
    2. Map smoothing method f6.0, 10.2 or 15.1
    3. Times of curve smoothing 3 times
    Thus obtained rCBFinitial functional image showed higher resolution and lower statistical error (mean RSD=1-4%) . All procedures required about 3 minutes.
    It is considered that rCBFinitial functional imaging is of special value for the assessment of regional blood flow and that it will be useful for daily clinical studies.
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  • Sachiko TOKUHISA, Haruhisa YOSHIKAWA, Shigeyasu ICHIHARA, Shigeo BABA
    1977 Volume 26 Issue 9 Pages 630-635
    Published: September 15, 1977
    Released: September 07, 2010
    JOURNALS FREE ACCESS
    Because of the reluctance to use radioactive isotopes in man no quantitative kinetic data are available for a wide variety of metabolic processes. However, recent developments in the use of gas chromatography/mass spectrometry (GC-MS) prompted this preliminary study to devise techniques using stable isotope (SI) labeled metabolites. Phenylalanine (Phe) was chosen as this prototype amino acid because its sensitive and specific assays are needed in the diagnosis of such inborn errors of metabolism as phenylketonuria. L-phenylalanine [arom.-d5] was synthesized from benzaldehyde [arom.-d5] ; yield being about 18% of theoretical.
    Prior to the quantitative determination of deuterated metabolites we have to determine the isotopic purity of Phe-d5. In IR of Phe-d5, 740 and 690 cm-1 band, which are assigned to the out-of-plane vibration mode of Carom, -H of monosubstituted benzene derivatives, disappeared completely, and 2, 280 cm-1 band, which is assigned to the stretching vibration mode of Carom.-d, appeared. Moreover, in NMR of Phe-d5, the signal of aromatic proton (7.25 ppm) was missing completely. From these data, we concluded Phe-d5 obtained here did not contain a perceptible amount of hydrogen on its benzene ring. Phe and Phe-d5 were measured as the enaminemethyl ester derivatives by GC-MS. Comparison of MS of the Phe-d5 ester with that of the Phe ester suggested that neither isotope effect in the fragmentation between protio. and deuterio forms nor d-p exchange reaction in mass spectrometer was observed. On the mass fragmentogram retention time of deuterio form was shoter than that of protoo form. It suggests that the quantitative determination must be done by the use of MID.
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  • Kunio CHAYA, Tadaaki KAGAMI, Norikatsu HAMAMURA
    1977 Volume 26 Issue 9 Pages 636-639
    Published: September 15, 1977
    Released: July 21, 2010
    JOURNALS FREE ACCESS
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  • Masayuki TAKASUGI, Tatsuya HIROTA, Osamu HASEGAWA, Kotaro KIMURA, Shig ...
    1977 Volume 26 Issue 9 Pages 640-643
    Published: September 15, 1977
    Released: July 21, 2010
    JOURNALS FREE ACCESS
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  • Yoshimi ONO, Koichi ASAKURA, Eiji OHTAKE, Morimichi UJIIE, Takeo NOZAW ...
    1977 Volume 26 Issue 9 Pages 644-646
    Published: September 15, 1977
    Released: July 21, 2010
    JOURNALS FREE ACCESS
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  • Kouichi YUITA
    1977 Volume 26 Issue 9 Pages 647-656
    Published: September 15, 1977
    Released: July 21, 2010
    JOURNALS FREE ACCESS
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  • Hisao YAMASHITA, Shozo HASHIMOTO, Yukifusa TANAKA
    1977 Volume 26 Issue 9 Pages 657-663
    Published: September 15, 1977
    Released: July 21, 2010
    JOURNALS FREE ACCESS
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  • Kiyori NAKATO, Yoshikazu YOSHIDA
    1977 Volume 26 Issue 9 Pages 664-672
    Published: September 15, 1977
    Released: July 21, 2010
    JOURNALS FREE ACCESS
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  • 1977 Volume 26 Issue 9 Pages A1755-A1306
    Published: September 15, 1977
    Released: July 21, 2010
    JOURNALS FREE ACCESS
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