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The importance of oxygen in maintaining the functional integrity of hepatocytes has been well established in a variety of experimental models, such as in vivo , perfused liver and isolated hepatocytes. However, one of the shortcomings of these systems is their short life span. Therefore, we have examined the effects of long-term hypoxia on cellular adenine nucleotide content and cellular functions, such as albumin production, urea production and DNA synthesis, in adult rat hepatocytes in primary culture. Hepatocytes were cultured at a density of 11 × 104 and 5 × 104 cells/0.18 mL per cm2 for the study of albumin and urea production and DNA synthesis, respectively, at various oxygen tensions (20, 12, 8 and 5%) for 24 h. Cellular ATP content in cultured hepatocytes in hypoxia gradually declined, corresponding to the decrease in oxygen tension, and the cellular ATP level at 5% oxygen was approximately 20% of that at 20% oxygen. Albumin production also decreased in parallel with the decrease in cellular ATP content in cultured hepatocytes in hypoxia. However, even when cellular ATP content gradually declined corresponding with the decrease in oxygen tension in cultured hepatocytes in hypoxia, such as at 8 or 5% oxygen, urea production remained at a high level; in contrast, DNA synthesis was completely suppressed. These results suggest that the cellular ATP content decreases in cultured hepatocytes during long-term hypoxia in relation to oxygen tension and that the relationship between decreased ATP levels and liver function in cultured hepatocytes during hypoxia differs for albumin production, urea production and DNA synthesis.  相似文献   
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Abstract Lennox-Gastaut syndrome (LGS) is regarded as a model of the epileptic syndrome because of its specific clinicoelectrical manifestation. However, a close investigation reveals that its outline is somewhat vague, having the borderland around it. Precise diagnosis in an individual case is not always easy. In this paper, the diagnostic criteria of LGS are described. According to these criteria, cases with LGS were subclassified into the typical and the atypical cases, and also cases in the borderland of LGS were reviewed. On the other hand, our prospective long-term follow-up study revealed that cortical mechanisms played an important role in the pathophysiology, clinical features and refractoriness of LGS. Secondary bilateral synchrony (SBS) is supposed to be a mode of expression of cortical mechanisms of LGS. A newly developed method with coherence and phase analysis demonstrated that the pathophysiology was based on SBS in 33% of the typical LGS cases. This finding is not only crucial for the choice of rational treatment including epilepsy surgery, such as callosotomy, but also contributes to a more refined subclassification of LGS.  相似文献   
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Catheter Ablation for Mahaim Pathways. Introduction : Several modalities of catheter ablation have been proposed to eliminate Mahaim pathway conduction. However, limited research has been reported on the electrophysiologic nature of this pathway in its entity.
Methods and Results : In seven patients, electrophysiologic study was performed, and radiofrequency energy was applied to investigate the electrophysiologic clues for successful ablation. In all seven patients, the Mahaim pathway was diagnosed as a right-sided atriofascicular or atrioventricular pathway with decremental properties. In two patients, two different kinds of electrograms were recorded through the ablation catheter positioned at the Mahaim pathway location: one was suggestive of conduction over the decremental portion, demonstrating a dulled potential; and the other of nondecremental conduction, demonstrating a spiked potential. All but one of the Mahaim pathways were eliminated successfully at the atrial origin where the spiked Mahaim potential was recorded. Radiofrequency energy application was performed at the slow potential site resulting in failure to eliminate the conduction over the Mahaim pathway. Conduction block at the site between the slow and fast potential recording sites was provoked by intravenous administration of adenosine, concomitant with a decrease in the amplitude of the Mahaim potential. In one patient, the clinical arrhythmia was a sustained monomorphic ventricular tachycardia originating from the ventricular end of the Mahaim fiber.
Conclusion : The identification of Mahaim spiked potentials may be the optimal method to permit their successful ablation. Detailed electrophysiologic assessment is indispensable for successful ablation of tachycardias associated with Mahaim fibers because tachycardias unassociated with Mahaim fibers can occur despite complete elimination of the Mahaim fiber.  相似文献   
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From the foregoing analysis of the inhibitory action of -aminocaproic acidin the fibrinolytic process, it is evident that the process involves two reactionphases, fibrinolysis and metafibrinolysis.

Fibrinolysopeptide and metafibrin are split off from fibrin in fibrinolysis.The former is a peptide with N-terminal glycine, while the latter is a monochloracetic acid-soluble metaprotein having both aspartic acid and tyrosineas N-terminal amino acids.

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BACKGROUND: Transabdominal ultrasonography was used to study the bladder neck morphology in women with urethral syndrome or stress urinary incontinence, in order to determine the ultrasonographic findings of these conditions. METHODS: A total of 210 female patients with a normal bladder, asymptomatic trigonitis, urethral syndrome, and stress incontinence were studied. The mucosal thickness around the bladder neck, the length of the anterior base plate of the bladder, and the anteroposterior vesical wall angle (APVA) at the bladder neck were measured on sagittal transabdominal vesical ultrasonograms with the patient in the supine position. RESULTS: Patients with asymptomatic trigonitis or urethral syndrome had thicker mucosa around the bladder neck than the subjects with a normal bladder, and the subjects with stress incontinence had normal mucosa. The APVA was 158 +/- 17 (mean +/- SD) degrees in the subjects with a normal bladder. It was smaller in symptomatic patients and decreased to 109 +/- 10 degrees in those with conservative therapy-resistant incontinence. The anterior edge of the vesical base plate was visible approximately 2 cm from the bladder neck in subjects without incontinence, while it tended to be absent in patients with incontinence and an APVA of less than 126 degrees. CONCLUSION: A small APVA appears to reflect bladder neck descent, while a small APVA without a visible anterior base plate edge may reflect hypotonia of the vesical base plate. Transabdominal vesical ultrasonography with the patient in the supine position provides useful information and can be carried out as a routine examination in female patients with micturition disorders.  相似文献   
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