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Pathology of the intrahepatic bile ducts bearing calculi was examined with an emphasis on metaplasia in 22 cases of hepatolithiasis and in seven cases of normal livers. Normal livers contained few glandular elements within the bile duct walls and no metaplastic lesions or endocrine cells. In hepatolithiasis, a number of mucous glands resembling pyloric glands (pseudopyloric gland metaplasia) were seen within duct walls in all cases. The epithelial cells of the glands were positive for class III mucin with paradoxical concanavalin A staining which is known to be specific for pyloric glands. These cells were also positive for neutral, sialo- and sulfomucin to a variable extent. Intestinal metaplasia, including goblet cell and Paneth cell metaplasia, was found within duct walls and in covering epithelia in five (23%) cases. Endocrine cells, including argyrophil, argentaffin and gut hormone-containing cells were present in these metaplastic lesions in 13 (59%) cases. The occurrence of endocrine cells was closely associated with intestinal metaplasia, although there were a few endocrine cells in metaplastic pseudopyloric glands. These findings suggest that metaplastic lesions similar to the well-known metaplastic lesions in the gallbladder occur in the intrahepatic bile duct walls in hepatolithiasis. The appearance of metaplastic lesions and endocrine cells may be causally related to chronic inflammatory processes associated with hepatolithiasis.  相似文献   
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Background and objective: Bronchiolitis obliterans (BO) has been reported to develop following ingestion of Sauropus androgynus (SA), a leafy shrub distributed in Southeast Asia. Little is known about direct effects of SA on airway resident cells or haematopoietic cells in vitro. Identification of the SA component responsible for the development of BO would be an important key to elucidate its mechanism. We sought to elucidate the direct effects of SA on airway resident cells or haematopoietic cells and identify the SA element responsible for the pathogenesis of BO. Methods: SA dry powder was partitioned into fractions by solvent extraction. Human and murine monocytic cells, epithelial cells and endothelial cells were cultured with SA solution or fractions eluted from SA. We also investigated the effect of SA in vivo using a murine BO syndrome (BOS) model. Results: The aqueous fraction of SA induced significant increases of inflammatory cytokine and chemokine production from monocytic lineage cells. This fraction also induced significant apoptosis of endothelial cells and enhanced intraluminal obstructive fibrosis in allogeneic trachea allograft in the murine BOS model. We found individual differences in tumour necrosis factor α (TNF‐α) production from monocytes of healthy controls stimulated by this aqueous fraction of SA, whereas it induced high‐level TNF‐α production from monocytes of patients with SA‐induced BO. Conclusions: These results suggest that an aqueous fraction of SA may be responsible for the pathogenesis of BO.  相似文献   
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Objective To detect the presence of Tannerella forsythus(Tf)and Prevotella intermedia (Pi) using polymerase chain reaction(PCR) in the oral plaque samples from children and investigate the relationship between bacteria and clinical parameters. Methods A total of 151 children aged 7 to 12 years were selected from Changchun primary school. The supragingival plaque sample was collected from the mesiobuccal and labial surfaces of the right maxillary central incisor ( FDI 1 ) and the right maxillary first molar ( FDI 6 ). Extracted DNA from plaque samples was used for PCR analysis. Intraoral examination,probing depth (PD) and bleeding on probing (BOP) were performed and recorded. Results The detection rate for Tf was 40. 3% ( 118/293 ) and Pi was 46. 4% ( 136/293 ) in supragingival plaque. The detection rates for Tf and Pi in molars were much higher than those in incisors( P <0. 01 ). The detection rate of Tf and Pi was positively related to BOP + and PD. The detection rate for Pi decreased gradually with age, and the detection rate for Tf was highest in the group aged 7 to 8 and the detection rates for Tf and Pi were higher in the gingiva with BOP + than that with BOP - ( P > 0. 05 ). The detection rates for Tf increased remarkably with BOP + and especially when PD was greater than 4 mm. Conclusions Detection rates of putative periodontal pathogens from healthy children of 7 to 12 years of age were high. The detection rates for Tf and Pi in molars were much higher than those in incisors, and the presence of Tf and Pi in supragingival plaque was related to periodontal parameters.  相似文献   
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目的探讨23-羟基白桦酸对人结肠癌细胞株LoVo细胞增殖和凋亡的影响。方法采用MTT法检测23-羟基白桦酸对LoVo细胞的增殖抑制作用。Hoechst染色、流式细胞仪检测细胞凋亡及线粒体膜电位的变化。结果23-羟基白桦酸能抑制LoVo细胞的增殖,其作用呈明显的时间和剂量依赖性。Hoechst33258染色显示细胞凋亡特征。23-羟基白桦酸25、50、100及200μmol·L-1作用LoVo细胞48h后,其凋亡率分别为11.32%±0.92%、19.23%±0.78%、24.51%±5.88%及42.22%±2.32%,显示一定的剂量依赖性关系。与空白组相比,23-羟基白桦酸可明显降低LoVo细胞线粒体膜电位(P<0.01)。结论23-羟基白桦酸可抑制LoVo细胞的增殖,其机制与降低线粒体膜电位继而诱导LoVo细胞凋亡有关。  相似文献   
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To observe the secular trend of a proportion of Kawasaki disease patients with cardiac sequelae in Japan, we analyzed patients with Kawasaki disease reported to nationwide surveys of the disease during 10.5 years from July 1982 to December 1992. Of 69 382 patients reported to the surveys, 10 596 (15.3%) were reported to have cardiac sequelae such as dilatation or stenosis of coronary arteries, myocardial infarction or valvar lesions, 1 month or more after onset. The percentage of cardiac sequelae was particularly high in males, infants younger than 1 year and children older than 5 years of age. The overall prevalence declined steadily over the observed period. However, the percentage for children older than 5 years of age did not decrease, whether treated with intravenous gamma globulin or untreated. As a consequence of the increased number of patients treated with intravenous gamma globulin, the proportion of Kawasaki disease patients with cardiac sequelae decreased annually. However, the proportion of children older than 5 years of age did not decrease.  相似文献   
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The present study examined chronotropic dysfunction and the role of vagotony in congenital long QT syndrome, sinus node function and the effects of parasympathetic blockade. Six patients with congenital long QT syndrome were studied. The four males and two females, aged 1–15 years, had episodes of syncope and malignant ventricular arrhythmias. Congenital long QT syndrome was defined as a corrected QT interval greater than 0.45 s, T wave alternans and the age at diagnosis. The sinus heart rate measured from a 24 h electrocardiograph was abnormally low (< 50 min) in three patients (1, 4 and 5 years old) and did not increase sufficiently with the administration of atropine in five of the six patients with congenital long QT syndrome. From intracardiac electrophysiological studies, the corrected sinus node recovery time was prolonged in three patients and the total sinoatrial conduction time was prolonged in two patients. In most patients who had an abnormally long sinoatrial conduction time and corrected sinus node recovery time, these values returned to normal following atropine administration. In one patient, the corrected sinus node recovery time was prolonged paradoxically by atropine. Sinus node dysfunction in congenital long QT syndrome was affected by vagotony associated with a right sympathetic nerve system abnormality.  相似文献   
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