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We developed a constant-flow perfusion system to measure vascular responses to vasoactive agents applied intraluminally or extraluminally. The intraluminal and extraluminal sides of a cylindrical section of rabbit basilar artery were isolated completely. By loading with 0.75 g of tension, the resting condition of each preparation was made constant. The intraluminal side was perfused at a constant flow of 8 ml/min and under an intraluminal pressure of 8 mm Hg. When 30 mM KCl was administered intraluminally the preparation showed marked contraction, whereas only slight contraction was observed with extraluminal administration. When 2 x 10(-7) M 5-hydroxytryptamine was administered, no significant differences in contraction could be detected between the intraluminal and extraluminal routes. Application of 10(-6) to 10(-4) M acetylcholine after precontraction with 30 mM KCl resulted in much stronger dilatation upon intraluminal application. Thus, it was demonstrated that under certain conditions significant differences exist in the responses of rabbit basilar arteries to vasoactive agents applied intraluminally or extraluminally. This system can detect the effects of vasoactive agents administered intraluminally and extraluminally at a high level of sensitivity and shows good reproducibility as a means of analyzing vascular functions and characteristics.  相似文献   
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We present two female siblings with familial juvenile nephronophthisis (FJN) which was diagnosed at the early stage of renal failure. Diagnosis was made during the investigation of anemia in case 1 and by a subsequent family survey in case 2. Most patients with FJN are not identified until the terminal stage of renal failure and such cases have rarely been reported in Japan. Case 2 had a reduction in the maximum urinary concentration ability but no azotemia, and among the FJN patients reported in Japan so far she has the least advanced renal disease. Histological examination of the renal biopsy in case 1 showed typical findings of FJN, such as thickening and lamination of the tubular basement membrane (TBM), interstitial fibrosis, and round cell infiltration of the interstitium. In case 2, renal biopsy revealed an irregular marked thickening of the TBM with trivial interstitial changes and a normal glomerular appearance. The histology of these two cases suggests that the TBM may be the primary site affected in FJN.  相似文献   
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Tumor scintigraphy with 67Ga-citrate, 99mTc(V)-DMSA and 99mTc-MDP were performed on a patient with rare primary pulmonary leiomyosarcoma. While 67Ga-citrate accumulation to the tumor was not recognized, 99mTc(V)-DMSA and 99mTc-MDP scintigraphy showed relatively intense localization of the tracers in the lesion, and were very useful in suggesting the characteristics of the tumor.  相似文献   
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In embryology, a persistent connection of the left superior vena cava to the left atrium rarely coexists with a coronary sinus. We herein report an unusual case of persistent left superior vena cava terminating in a left atrium with normal coronary sinus, which was revealed at the time of permanent pacemaker implantation after a second operation for recurrent left atrioventricular valve regurgitation. Because this anomaly had gone undiagnosed at the first operation, we were unable to diagnose it prior to the second operation, because the preoperative coronary angiogram clearly demonstrated a coronary sinus that was not dilated. We would have repaired the anomaly using a patch or other procedure had it been diagnosed before the second operation in order to prevent cyanosis or brain complications secondary to right-to-left shunting. One should always be on guard for this rare condition.  相似文献   
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Twenty-two hydrocephalic patients with a ventriculoperitoneal shunt using a continuously variable flow resistance valve (Orbis-Sigma valve system; Cordis Corporation, USA) were reviewed to discuss usefulness of the shunt system. We divided the cases into two groups according to the demonstration of the cortical sulci in computed tomography (CT) as follows; A: progressive hydrocephalic cases mimicking simple brain atrophy, B: acute or subacute hydrocephalic cases with evidence of increased intracranial pressure. Patients in Group A had begun to present slowly progressive loss of activity, dementia and gait disturbance of various degrees after a long quiescent period following primary central nervous system injury. CT findings of these cases showed they were mimicking simple brain atrophy. Although the period of their deterioration was very long, ranging from 1 month to nine years, clinical signs improved in all cases after the shunt. None showed complications. Group B cases consisted of those with signs of increased intracranial pressure such as consciousness disturbance, nausea and vomiting. These cases showed poor demonstration of the cortical sulci in CT. Eleven out of thirteen cases showed satisfactory clinical improvement, though the size of the ventricle showed a slight decrease following shunt procedure. Only one case showed unilateral subdural effusion. In conclusion, this shunt system is useful for the management of ventricular enlarged cases mimicking simple brain atrophy as well as acute hydrocephalic cases. Troublesome consequences such as subdural effusion and hemorrhage rarely occur even in cases with low cerebrospinal pressure.  相似文献   
29.
Body temperature monitoring in subjects with delayed sleep phase syndrome   总被引:2,自引:0,他引:2  
To clarify the circadian aspects of delayed sleep phase syndrome (DSPS) in 4 patients with DSPS, we recorded polysomnograms and rectal temperature before and after chronotherapy. The time interval (2.7 h) between sleep onset and rectal temperature minimum before chronotherapy was shorter than the time interval after chronotherapy (5.3 h). Before chronotherapy, the period of rectal temperature rhythm was 24.7 h. After chronotherapy, the period of rectal temperature rhythm was 24.0 h. These findings lead to the conclusion that in DSPS there is a weakened mechanism of entrainment similar to that in non-24-hour sleep-wake syndrome.  相似文献   
30.
Intraperitoneal injection of free valproic acid (VPA) suppressed amygdaloid-kindled seizure 1 h after injection in rats, but had no effect at 24 h. VPA entrapped in positively charged liposomes showed a prolonged anticonvulsant effect lasting for 2 days, while the effect evaluated at 1 h was not different from that with free VPA. VPA entrapped in negatively charged liposomes exerted a significantly stronger effect at 1 h than did free VPA, while it had no significant effect at 24 h. These results suggest that surface charges on liposomes play an important role in modifying the anticonvulsant effect of VPA.  相似文献   
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