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The antitumor activities of KW-2152, a new isoquinon derivative, were examined in thirteen human tumor xenografts, transplanted into nude mice. KW-2152 was administered intravenously at a schedule of q4d X 3, in daily doses of 7.3 mg/kg and 3.6 mg/kg, and q2d X 6 with a daily doses of 7.3 mg/kg, respectively. KW-2152 displayed significant antitumor activities against the human tumor xenografts in 3 out of 13 strains (23.1 per cent) at the schedule of q4d X 3, with a daily dose of 7.3 mg/kg. Depending on the schedule of administration, tumor activity was observed in 8 out of 13 strains (61.5 per cent) at a schedule of q2d X 6, with a daily dose of 7.3 mg/kg. SH-2 and SH-9 gastric tumors were sensitive to KW-2152 and growth was completely inhibited with the schedule of q4d X 3, and a daily dose of 7.3 mg/kg. Thus, KW-2152 seems to have a wide antitumor spectrum, and the possible antitumor effects for clinical use, warrant attention.  相似文献   
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The magnetic resonance phase-contrast technique for the measurement of flow velocity and volume in true and false lumens was studied in six patients with chronic dissecting aneurysms. Phase-contrast images were obtained at a level perpendicular to the dissecting aneurysms of the descending aorta. As the maximum diameter of aneurysms increased, the ratio of the cross-sectional area of the false to the true lumen increased and the peak average velocity in the true lumen during systole was decreased. This technique proved invaluable for determining prognosis and operability for this condition.  相似文献   
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The topical organization of thalamic projections to the second and fourth somesthetic areas in the anterior ectosylvian gyrus of the cat has been studied using the technique of retrograde axonal transport of horseradish peroxidase. The projections of the posterolateral and posteromedial ventral nuclei (VPL, VPM) to the second somesthetic area (SII) are organized somatotopically. The posterior portion of SII (hindlimb area) receives fibers mainly from the dorsolateral part of VPL, the middle portion of SII (forelimb area) from the ventromedial part of VPL, and the anterior portion of SII (face area) from VPM. These topical projections are more loosely organized and less densely arranged than those to the first somesthetic area. The SII receives a few fibers from the medial geniculate nucleus, particularly its magnocellular and dorsal principal parts, and from the suprageniculate nucleus. The posterior part of SII lying near the secondary auditory area receives many fibers from the medial geniculate and suprageniculate nuclei, and only a few fibers from the lateral central and paracentral nuclei. The fourth somesthetic area (SIV), located in the dorsal bank of the anterior ectosylvian sulcus, receives fibers mainly from the dorsal principal and magnocellular parts of the medial geniculate nucleus, and from the suprageniculate nucleus. The SIV receives a fair number of fibers from VPL and VPM roughly in a somatotopical manner. The posterior portion of SIV receives fibers chiefly from the dorsolateral part of VPL, the middle portion of SIV from the ventromedial part of VPL, and the anterior portion from VPM. In addition, SIV receives a few fibers from the lateral central, paracentral, ventral lateral and ventral medial nuclei. The SIV, together with the most posterior part of SII, forms an auditory area, receiving many fibers from the medial geniculate and suprageniculate nuclei, and a few fibers from the intralaminar nuclei.  相似文献   
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Abstract: To be able to salvage heart failure patients, the need for an economical permanent ventricular assist device is increasing. To meet this increasing demand, a miniaturized centrifugal blood pump has been developed as a permanently implantable device. The Gyro permanently implantable model (PI-601) incorporates a sealless design with a blood stagnation free structure. The pump impeller is magnetically coupled to the driver magnet in a sealless manner. This pump is atraumatic and antithrombogenic and incorporates a double pivot bearing system. A miniaturized actuator was utilized in this system in collaboration with the University of Vienna. The priming volume of this pump is 20 ml. The overall size of the pump actuator package is 53 mm in height and 65 mm in diameter, 145 ml of displacement volume, and 305 g in weight. Testing to date has included in vitro hydraulic performance and hemolysis. This pump can provide 5 L/min against a 110 mm Hg total pressure head at 2,000 rpm and 8 Limin against 150 mm Hg at 2,500 rpm. The normalized index of hemo-lysis (NIH) value of this pump was 0.0028 g/100 L at 5 Limin against 100 mm Hg. A preliminary anatomical study revealed the possibility of the implantability of 2 such systems in biventricular bypass at a preperitoneal location. This system is feasible for use as a permanently implantable biventricular assist device.  相似文献   
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The role of endothelial cells in the histamine-induced vascular response was investigated using cultured endothelial cells obtained from human umbilical veins. A single population of histamine H1 receptors was detected in these cells by means of a [3H]mepyramine binding assay. Its Kd was 0.74 +/- 0.07 nM and Bmax was 41.4 +/- 8.68 fmol/mg protein. Actin filaments were distributed as dense bands at the margin of the cells and as sparse microfilament bundles traversing the center of the cells. Histamine caused a decrease in peripheral bands and an increase in longitudinal bands. The changes evoked by histamine were dose-dependent, related to the duration of incubation of the cells with histamine, and blocked by mepyramine, a histamine H1 receptor antagonist. The results suggest that the endothelial cells respond to histamine through the histamine H1 receptor. This may explain one of the mechanisms of histamine-induced vascular response including vascular permeability increase.  相似文献   
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