A method for locating reinforcing bars in reinforced concrete by backscattered γ-rays was studied using137Cs and133Ba. Experiments were carried out by projecting a collimated γ-ray beam with an incident angle of 90° or 45° to a surface of sample concrete and detecting γ-rays backscattered at an angle of 135° with a NaI (Tl) scintillator fitted with a collimator. From the backscattered counting rate obtained by scanning a surface of the reinforcing concrete, the spacing, size and depth of the reinforcing bars could be measured relatively precisely when the bars were buried near the surface of concrete.
A series of animal models for portal hypertension was prepared using the method of portal vein constriction. Four New Zealand domestic rabbits and six dogs were given portal imaging by per-rectal administration of99mTc-MIBI and characteristics of quantitative portal hypertension were investigated. When the portal of domestic rabbits were constricted to 1/2, the heart/liver value (H/L) rose from 0.10±0.04 to 0.57±0.11, and the heart shunt index (S.I.h) rose from 0.08±0.03 to 0.36±0.09. These differences have significant meanings (p<0.05) . The shunt index for whole organs (S.I.w), however, only changed slightly. When the portal veins of the dogs were constricted to 1/3, 1/2 and 2/3 of their original widths, their H/L, S.I.h and S.I.w values rose in proportion respectively, and their correlation with the portal pressure measured during operation was very good. Immediately after the operation, the main feature observed was the compensational swelling of the spleen. One month later, image of the heart became even more conspicuous, demonstrating formation and establishment of the collateral circulation.
In this study, the effect of coronary artery bypass grafting (CABG) in 35 patients (pts) (male 29, female 6) with fixed defects were evaluated before and one month after surgery using resting201T1 SPECT. Nine pts (7 old myocardial infarction ; OMI) had 2 vessel disease (VD) and 26 pts (19 OMI) had 3 VD. Pts ages ranged from 41 to 75 (mean 61.4±8.4) years. All 35 pts were divided into 4 groups according to the results of201T1 SPECT and left ventriculogram pre- and post-CABG. 13 pts who improved of both201T1 SPECT and wall motion scores post-CABG were considered as hibernating myocardium (group I) . 9 pts who impoved of201T1 SPECT score but no change of wall motion were group II. 7 pts who improved of wall motion but no change of201T1 SPECT score were group III. 6 pts who had no improvement of both201T1 SPECT and wall motion scores were group IV and considered as myocardial infarction.
An automatic photographic system of the afterglow colour images (AGCI), which give very useful information related to crystal defects and impurities in white inorganic materials, has been developed. The present system consits of a combination of a phtographic part installed in a dark bag with a control personal computer through an interface board. Thus, the photographic procedure of the successive and clear AGCIs could be accomplished from the direct contact of a colour film with an X-rays irradiated rock slices for desired exposure periods and interval times. By using this system, some AGCIs of ammonite fossil showed interesting changes of orange patterns due to structural fossil calcite.