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11.
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   
12.
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   
13.
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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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   
17.
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   
18.
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   
19.
The intestinal absorption of glucose- and galactose-conjugated compounds was studied in the everted sac of the rat small intestine. The absorption clearance of p-nitrophenyl beta-D-glucopyranoside (p-NPglc) at 250 microM in the mucosal side (4.45 +/- 0.34 microL/min/cm, mean +/- SE, N = 4), calculated by dividing the absorption rate by the drug concentration, was significantly decreased (0.476 +/- 0.036 microL/min/cm) in the presence of 1 mM phloridzin, an inhibitor of glucose transport, and in the absence of Na+, a cosubstrate of the glucose transport carrier (0.424 +/- 0.018 microL/min/cm). The absorption clearance of p-NPglc was decreased as its concentration increased. In the same experiment, the absorption clearance of p-nitrophenyl beta-D-galactopyranoside (1.99 +/- 0.23 microL/min/cm) was also significantly decreased in the presence of phloridzin and in the absence of Na+. However, the absorption clearance of p-nitrophenyl beta-D-mannopyranoside (0.811 +/- 0.013 microL/min/cm) was low and not significantly decreased in the presence of phloridzin (P greater than 0.1). Furthermore, the absorption clearance of beta-naphthyl beta-D-glucopyranoside and beta-naphthyl beta-D-galactopyranoside was also significantly decreased in the presence of phloridzin (P less than 0.001). These results indicated that the glucose and galactose moieties provided these compounds with a new route by way of the glucose transport carrier for intestinal absorption.  相似文献   
20.
K Abe  M Ohta 《Psychopathology》1992,25(4):218-228
Published cases of periodic psychosis of puberty and related papers were reviewed. The clinical picture is near-monthly recurrence of episodes of stupor or excitement lasting about 1 or 2 weeks, which are accompanied by delusion and in some cases also by hallucinations or confusion. This condition was found to occur more commonly in girls than in boys, and in half of the girls reported the episodes tended to start a few days before menses. Adolescents with mental retardation were more commonly affected, and this suggests that organic brain damage may play a role in the etiology in some cases. Short-term prognosis is usually favorable, but at long-term follow-up, nearly half of them were found to be suffering from affective or schizophrenic illness. The clinical importance of recognizing this psychosis early in the course of illness is emphasized.  相似文献   
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