[en] Before laparoscopic cholecystectomy, it is important to clarify the anatomy of the cystic duct. This study assessed three-dimensional CT images (3D images) of the cystic duct obtained non-invasively using helical DIC CT and these images were compared with those obtained with ERCP and DIC. The three-dimensional technique using helical DIC-CT was applied in 168 patients for laparoscopic cholecystectomy. The cystic duct detected by 3D imaging was evaluated for patency, length and bifurcation. Three-dimensional images showed the cystic duct in 157 of 168 cases (93.5%) and in 81 of 89 cases (91%) in which the cystic duct was not clearly visualized on DIC. Among the 23 cases in which both 3D images and ERCP was performed, 3D images were equal to those of ERCP in detection of the cystic duct in 20 cases, superior to ERCP in two cases, and inferior to ERCP in one. The technique of 3D images proved its usefulness in demonstrating the patency, length and variations in bifurcation of the cystic duct for surgeons performing laparoscopic cholecystectomy and might be substitute ERCP in preoperative assessment. (author)

[en] This paper introduces the vibrational characteristics of the fluid-coupled cylinder under the seismic loading. Theoretical and experimental investigations of a cylindrical shell and coaxial cylinder were conducted for the acrylic model tank of 850 mm in height, 800 mm in outer shell diameter and 300 mm in inner shell diameter. From these investigations, the following results were obtained. 1. Experimental and analytical results regarding the natural frequencies, mode shapes, and hydrodynamic pressure distributions were compared and good agreements were found for both cases of the coaxial cylinder and the cylindrical shell. 2. The damping ratio of the cylindrical shell obtained from the transfer function is about 5 % and the damping ratio of the coaxial cylinder varied from 5 % to 11 % according to the water level. 3. The fundamental natural frequency (n = 1) of the coaxial cylinder becomes lower than that of the cylindrical shell because the fluid has a considerable inertial effect on the shell. The natural frequencies of the coaxial cylinder were closer to those of the cylindrical shell for higher circumferential mode number (n > 5). (author)

[en] We prospectively evaluated CT images of the lower lung on lung window setting in the abdominal CT. In 1.151 abdominal CT examinations CT image on lung window setting detected pulmonary lesions on 120 examinations (10.4%). Pulmonary lesions included nodules, inflammatory changes, bullae, emphysema, bronchiectasia and others. CT images on abdominal window setting and chest radiography showed those lesions only in 40.9% and 53.4% respectively. To display lung images on lung window setting in the abdominal CT scan provides more useful informations without additional cost or irradiation. Especially in the patients with malignancy, pulmonary metastasis can be found earlier. (author)

[en] The neutron halo nucleus has been vigorously studied as a unique entity that appears near the neutron drip line. Taking advantage of the difference in sensitivity between Coulomb breakup reaction and nuclear force breakup reaction, the authors performed nuclear spectroscopic studies on ³⁷Mg and ²⁹Ne nuclei near the neutron drip line, and identified that these ground states have p-wave halo structure. Furthermore, for ³⁷Mg, they determined the spin parity and neutron separation energy of the ground state for the first time, and for ²⁹Ne, determined the spin parity of the ground state. (A.O.)

[en] By using the inverse scattering method the soliton solutions are examined analytically and numerically under both (I) vanishing and (II) nonvanishing conditions. The two-soliton solution for (I) shows that two solitons collide as if they were particles. For the case (II) there appears a ''paired soliton'' which generally pulsates with a period (''pulsative soliton'') but degenerates to a stationary one (''pure soliton'') in a limited case. There exist two types of pure solitons, envelope bright and dark solitons, between which some cases of collisions are examined. The collision between solitons of same types is similar to that of (I), while the other collisions are different from the previous case. (author)

[en] A mixed nonlinear Schroedinger equation which has a usual cubic nonlinear term and a derivative cubic term is exactly solved by the inverse scattering method under the nonvanishing boundary condition. We obtain the soliton solution which generally pulsates. But it becomes stationary which is algebraic in some special cases. A peculiar structure of spiky modulation is also shown. (author)

[en] Twelve patients who had neck and/or mediastinal masses were examined for their neck and mediastinal venous system by Intra-Venous Digital Subtraction Venography (IVDSV) and Conventional Venography (CV). In IVDSV, we were able to obtain clear images of their bilateral juglar veins without a unilateral obstructive image, but bilateral brachiocephalic veins and SVC were seen only faintly in most cases. When we could not seen latter veins in IVDSV, we needed CV to see them. So, when we want to observe the neck and mediastinal venous system, we think that both IVDSV via the femoral vein and CV via antecubital vein should be combined to use simultaneously or later. (author)

[en] Angiography has been reported to play an important role in the diagnosis of pancreatic insulinoma, and hematological examination on the blood sampled from the pancreatic veins by percutaneous transhepatic portal catheterization is also considered to have a diagnostic value. However, these two technique fail to localize tumor in some patients. Two patients in whom these conventional techniques had been useless underwent CT arteriography (with a contrast medium injected into the abdominal artery) and insulinoma was clearly visualized on CT scans. The diagnosis confirmed on surgery in both patients, appears to substanitiate the usefulness of CT arteriography in the diagnosis of pancreatic insulinoma. (author)

[en] DSA was employed using continuous intraarterial infusion tubes for various malignancies (73 cases) which were examined a total of 135 times. In head and neck malignancy (50 cases), the general position of the infusion tube had been determined beforehand by dye infusion, but DSA from the tube showed that the tubes in 24 cases (48 %) were located in the wrong position, especially in tongue cancer (21 cases) where many tubes were discovered to be in an erroreous position (71 %) such as the common carotid artery. We were unable to determine the effect of chemotherapy and radiation using DSA only. In 9 cases of breast cancer for which fixation of the tube was not attempted under X-ray fluoroscopy, 7 (78 %) showed an unusual tube position such as the intraaortic arch. In 5 cases of abdominal malignancy, only the tube position for sigmoid colon cancer was unusual. We were able to observe the effect of chemotherapy by DSA in 2 cases. For DSA in one out of 3 hepatomas using a Port-A-Cath, we observed that infusion of anticancer drug with degradable starch microspheres caused a reduction in tumor size. However, in the two remaining cases, we were unable to observe any effect of infusion of these drugs by DSA for various mechanical reasons. DSA from an infusion tube revealed not only the location of the tube accurately and promptly, but also the effect of chemotherapy. (author)

[en] The dynamic behavior of a flexible beam that is pulled into and drawn out of a gap in an elastic wall with a constant velocity is presented using a mechanical model and experiments. We focus particularly on the effects of the guide in front of the inlet of the wall gap and the fluid force on the beam behaviors. The presented model is verified to simulate well the behavior of the beam when the guide is provided in front of the inlet. In the case of the drawing out the beam, we found out that the fluid force works to be the beam destabilized, and the divergence type instability phenomena is caused in the beam due to the fluid force when the driving velocity is high or the density of the fluid is also high through numerical simulations