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91.
We studied the effect of increased endotoxin levels on the expansion modes of liver macrophages after two-thirds partial hepatectomy using anti-endotoxin polymyxin B. The expansion consists of dual modes: local proliferation and immigration. Local proliferation of mature cells was evaluated by the S-phase proportion measured by flow cytometric DNA analysis. This proportion (11.8 +/- 1.3% before hepatectomy) decreased to 6.0 +/- 1.1% at 12 h and reached a maximum of 21.9 +/- 2.7% on the 5th day after hepatectomy. In polymyxin B treated rats, the proportion reached a maximum of 21.1 +/- 1.6% at 48 h without any preceding decrease. Immigration of macrophage precursors was evaluated by the decreasing proportion of latex beads-containing cells that were marked as resident liver macrophages by injection of latex beads before hepatectomy. This proportion (98.7 +/- 0.2% before hepatectomy) was significantly decreased to 90.5 +/- 1.6% at 48 h. In polymyxin B treated rats, however, the proportion showed no significant decrease within 3 days. These results indicate that endogenous endotoxin, which suppresses the local proliferation and promotes extrahepatic recruitment, regulates the number of liver macrophages in regenerating rat liver.  相似文献   
92.
OBJECTIVES: Intestinal segments are frequently used in the reconstruction of the urinary tract. Chronic bacteriuria is frequently observed in these patients, but the reason is not clearly understood. Therefore, we studied the difference in bacterial adherence between bladder and ileum using the rat ileal augmented bladder model to investigate the cause of chronic bacteriuria. MATERIALS AND METHODS: Augmentation of the bladder using ileum and a sham operation were performed under sodium pentobarbital in 102 and 10 Sprague-Dawley rats, respectively. At three months after the operation, urinary pH and plasma concentration of sodium, chloride and potassium were measured and urinary culture was done. Urovirulence factors of Escherichia coli aspirated from augmented bladder were detected by polymerase chain reaction (PCR). Five to six rats with negative urinary cultures after the augmentation were used for each experimental cystitis. E. coli with type I pili aspirated from augmented rats and three clinically isolated strains of E. coli, C5 (type I pili, aerobactin), C92 (type I pili, aerobactin, P fimbriae), and C189 (type I pili, aerobactin, P fimbriae, CNF), were transurethrally inoculated into the augmented bladder of rats. Fourteen days after inoculation, rats were sacrificed and colony-forming units (CFU) per mg. of tissue of bladder and ileum were measured. RESULTS: After operation, urinary pH and the serum level of chloride in all augmented groups were higher than those of the controls. Bacterial colonization was observed in 56 of 89 rats. Most of them were E. coli having only type I pili as a virulence factor. In contrast, the sham operated group revealed no bacterial colonization. In experimental cystitis, E. coli with only type I pili aspirated from augmented rats and E. coli C5 were clearly adhered to ileum rather than to bladder, but E. coli C92 and C189 showed no significant difference with respect to adherence to the two tissues. In experimental cystitis II, E. coli C5 with D-mannose were washed out in 3 of 5 rats by 14 days, while E. coli C5 without D-mannose were not washed out in all rats by 14 days. CONCLUSIONS: These results suggested that the difference in bacterial adherence due to urovirulence factors, especially type I pili, is one of the main causes of asymptomatic bacteriuria after urinary reconstruction.  相似文献   
93.
Cone beam computed tomography (CBCT) images are degraded by artifacts due to endovascular implants. We evaluated the use of streak metal artifact reduction technique (SMART) in non-contrast CBCT images after endovascular neurosurgery obtained from 148 patients (125 with aneurysm and 23 with dural arteriovenous fistula [dAVF]). Three neurosurgeons evaluated the cistern and brain surface visibility in CBCT images with and without SMART correction based on a 4-point scale (1, excellent; 2, good; 3, limited; and 4, insufficient). Significant improvement in visibility was achieved when the median scores improved from 4 or 3 to 2 or 1 or from 2 to 1. Metal artifact reduction in adjacent slices without metal and new artifacts after SMART correction was also examined. A significant improvement was achieved regarding the visibility of the cistern in 90 (60.8%) images and of the brain surface in 108 (73.0%) images. Metal size (cistern: odds ratio [OR], 0.91 per 1 mm increase; 95% confidence interval [CI], 0.83–0.99), irregular metal shape (cistern: OR, 0.18; 95% CI, 0.05–0.60 and brain surface: OR, 0.15; 95% CI, 0.05–0.45), and infratentorial lesions (cistern: OR, 0.37; 95% CI, 0.14–0.96 and brain surface: OR, 0.30; 95% CI, 0.11–0.80) were negatively correlated with improved visibility. Metal artifact reduction in adjacent slices without metal was obtained in 25.6% and 34.8% of images with aneurysm and dAVF, respectively. New artifacts after SMART correction were found in 4.8% and 13.0% of images with aneurysm and dAVF, respectively. SMART is especially effective for supratentorial small aneurysms.  相似文献   
94.
Abstract We have reviewed retrospectively 229 patients interviewed by the mental health team in the Hachijojima since the establishment of our services in 1987. The 6 year observation period was classified into three chronological stages for the purposes of identifying any change in the utilization pattern of the mental health services of the island. The rate of schizophrenia was observed to have decreased from 48% in the first 2 years of the study period to 28% in the last 2 years; while that of other mental disorders increased yearly. Interestingly, an increasing number of patients were referred to our services by professionals in areas other than mental health (from 42 to 77%), and patients without any history of psychiatric treatment were more frequently seen (from 36 to 75%) in the later part of the study period. These changes suggest the importance of access to mental health services.  相似文献   
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97.
Radiofrequency (RF) catheter ablation of supraventricular tachycardias causes local parasympathetic denervation. This study used heart rate variability (HRV) to evaluate the effects of ablation of atrial tachycardia (AT) arising from the atrioventricular annulus (AVAT) on autonomic function. Ten patients with AVAT were referred for ablation (group AT) and compared with 8 patients with paroxysmal atrial fibrillation who underwent PV isolation (group Paf), and 13 patients with idiopathic ventricular tachycardia successfully treated by ablation (group VT). Time and frequency domain analysis of HRV on 24-hour ambulatory ECG recordings was performed before and after ablation. Root mean square of differences of consecutive N-N intervals (rMSSD), percentage of difference between consecutive N-N intervals >50 ms (pNN50), and high frequency (HF) component were measured to examine the effects on parasympathetic nerve activity. In group AT, rMSSD, pNN50, and HF decreased significantly after ablation, while they remained unchanged in group Paf and group VT. These observations suggest that parasympathetic denervation after ablation was limited to group AT, and depended on the site of energy delivery along the tricuspid or mitral valve as opposed to atrial or ventricular muscle.  相似文献   
98.
目的 探讨超声造影(contrast enhanced ultrasound,CEUS)联合免疫组织化学(immunohistochemistry,IHC)在术前诊断小肝细胞癌(hepatocellular carcinoma,HCC)微血管侵犯(microvascular invasion,MVI)中的价值。方法 回顾性收集日本横滨市立大学附属市民综合医疗中心和西安交通大学第一附属医院142例HCC患者的资料,包括177个新发的、最大直径不超过3 cm的HCC病灶。根据手术切除标本的病理学诊断分为MVI(+)组(n=37)和MVI(-)组(n=140)。在术前CEUS动脉期(arterial phase,AP)和血管后期(post-vascular phase,PVP)图像上分别观察病灶周边有无高灌注、低灌注;采用IHC检测热休克蛋白70(heat shock protein,HSP70)、磷脂酰肌醇蛋白聚糖3(glypican 3,GPC3)在术前穿刺活检标本中的表达。结果 CEUS指标(AP、PVP)和IHC指标(GPC3、HSP70)单独诊断MVI时,PVP的诊断效率最高,准确...  相似文献   
99.
An oral sustained-release cisplatin preparation was prepared by combining microporous water-insoluble pharmaceutical polymer, ethylcellulose, a membrane and a gel-forming polymer, poly(acrylic) acid (Carbopol). As cisplatin is an extremely hydrophilic and small compound, it was difficult to control the release rate solely by the micropores on the ethylcellulose capsule. To retain cisplatin within the capsule, gel-forming polymer was formulated inside the capsule. The release rate of cisplatin was dependent both on the number of micropores of the capsule and the formulated amount of Carbopol. The number of micropores ranged from 20 and 30 to 60, and the formulated amount of Carbopol varied from 15 to 100 mg. In-vitro release experiments suggested that the release rate decreased as the formulated amount of Carbopol increased when the pore number was 60 and 30. However, when pore number was decreased to 20, the effect of the amount of Carbopol was not clearly observed. In the in-vivo study using rabbits, the sustained-release cisplatin capsule was evaluated in comparison with solution after oral administration of 20 mg drug. With the pore number of 60, Cmax was 0.46 ± 0.02 μg mL?1 at 4 h and thereafter serum concentrations declined rapidly. When the pore number was 30, serum cisplatin level-time profiles showed long-acting patterns and AUC was reversely correlated with the formulated amount of Carbopol. Cmax and tmax were 0.41 ± 0.02 μg mL?1 and 3.33 ± 0.88 h, respectively and 0.23 ± 0.01 μg mL?1 was obtained at 24 h after oral administration of capsule having 30 pores and 15 mg of Carbopol. We conclude that the possibility of developing an oral sustained-release cisplatin preparation is feasible.  相似文献   
100.
Abstract Subjective sleep feelings and motor activity were measured in seven healthy elderly subjects for 6 days. The subjects were exposed to bright light (6000 lux) for 30 min in the morning or instructed to sit in front of a desktop lighting device without light. The average level of motor activity during the night was significantly decreased in the bright light condition, compared with the controlled condition. However, daytime motor activity did not show significant differences between the two conditions. From these findings, even a short duration of morning bright light is effective in maintaining sleep without changing daytime activity.  相似文献   
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