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91.
Proliferating Cell Nuclear Antigen Expression in Peribiliary Glands of Stone-Containing Intrahepatic Bile Ducts 总被引:2,自引:0,他引:2
All cases of hepatolithiasis showed features ofchronic proliferative cholangitis, and it has beenspeculated that the atypical glandular proliferationmight be a precursor to overt cholangiocarcinoma. Proliferative cell nuclear antigen (PCNA) is anuclear protein synthesized in the G1/S phaseof the cell cycle and therefore is related to cellproliferative activity. In an attempt to assess the activity of cell proliferation ofstone-containing intrahepatic bile ducts, we conducteda study using immunohistochemical staining withmonoclonal antibody to score PCNA in intrahepatic bileducts. Thirty patients (10 men, 20 women; mean age52.4 years) having hepatolithiasis surgically resectedwere studied. Ten stone-free patients served ascontrols. All 40 specimens were immunostained for PCNA using PC 10 monoclonal antibody. PCNA of bothstone-containing and stone-free intrahepatic bile ductswere assessed by counting positive staining nuclei per500 cells and expressed as labeling index (LI), ie, percentage of positive nuclei to the totalnumber of nuclei. The PCNA LI in stone-free intrahepaticbile ducts was generally low: 10.0 ± 13.2%, 10.4± 10.7% and 7.9 ± 9.6% for extramuralglands, intramural glands, and epithelial lining,respectively. In contrast, the PCNA LI forstone-containing intrahepatic bile ducts weresignificantly higher than those of controls (P <0.001): 49.4 ± 8.3%, 40.6 ± 7.0% and 34.1± 6.8% for extramural glands, intramural glands,and epithelial lining, respectively. The extramuralglands had a significantly higher PCNA LI (P < 0.001)than the intramural glands and controls. Hyperplasia was found inall specimens, while dysplasia was found in six of 30cases with hepatolithiasis. The dysplastic cells alsohad a higher PCNA LI (P < 0.001) than thehyperplastic cells and normal epithelium. Our findingsshowed that there is marked increase of activity of cellproliferation in stone-containing intrahepatic bileducts. It is well known that genetic mutations are facilitated in proliferating cells. Therefore,our results suggest that the high epithelial turnover indysplastic cells and extramural glands had higherpotential for proliferation and neoplastictransformation in long-standing untreatedhepatolithiasis. 相似文献
92.
Tzung-Shiahn Sheen Yu-Tzu Huang Yih-Leong Chang Jenq-Yuh Ko Chung-Shun Wu Yu-Chen Yu Ching-Hwa Tsai Mow-Ming Hsu 《Cancer science》1999,90(12):1285-1292
Latent membrane protein 1 (LMP-1) is the only Epstein-Barr virus (EBV)-encoded oncogenic protein that has been detected in nasopharyngeal carcinoma (NPC), a cancer that is closely associated with EBV. Previous in-vitro studies have demonstrated that LMP-1 can upregulate epidermal growth factor receptor (EGFR) in epithelial cells. It was not established whether this cellular effect exists in NPC. To assess the association between LMP-1 and EGFR in NPC tissues, 60 NPC specimens were examined by immunohistochemistry using anti-LMP-1 antibody (CS 1–4) and anti-EGFR antibodies (EGFR 1, EGFR 1005). The results revealed that 41 (68.3%) specimens were immunopositive for LMP-1 and 44 (73.3%) specimens over-expressed EGFR. Morphologically, the expressions of LMP-1 and EGFR were homogeneously distributed in the tumor nests. In addition, the correlation between LMP-1 and EGFR was statistically significant (P<0.001, χ2 test, d.f.=1). To elucidate further the correlation between LMP-1 and EGFR in vivo and in situ , an indirect dual immunofluorescence assay was conducted, using secondary antibodies conjugated with fluorescein isothiocyanate (FITC) or indocarbocyanine (Cy3). The results disclosed an intimate co-expression of LMP-1 and EGFR. In summary, the data indicate that over-expression of EGFR is a common phenomenon in NPC, and that EGFR is co-expressed with LMP-1 in NPC. Thus, EBV may play a role in the tumorigenesis of NPC through the effects of LMP-1 and EGFR. 相似文献
93.
NJ Hoogenraad JD Mitchell NA Don TM Sutherland AC Mc Leay 《Archives of disease in childhood》1980,55(4):292-295
The activity of urea cycle enzymes was assayed in duodenal biopsy specimens obtained from a female infant who presented with neonatal hyperammonaemia. All enzyme levels were normal except N-acetyl glutamate-dependent carbamyl phosphate synthetase 1 (CPS1) which was half the mean activity in normal control specimens. A similar deficiency of CPS1 was also shown in duodenal specimens from the patient's mother who became slightly symptomatic after relatively high protein meals and during pregnancy, and had spontaneously modified her diet to one with protein restriction. The patient is growing normally on a dietary regimen similar to that spontaneously adopted by her mother. Urea cycle enzyme activity in the duodenal biopsy material from the controls was similar to that found in the normal human liver and appears to have distinct advantages as a means of assaying for urea cycle defects in patients with hyperammonaemia and their relatives. 相似文献
94.
GM Durbin NJ Hunter N McIntosh EO Reynolds PD Wimberley 《Archives of disease in childhood》1976,51(3):163-169
A controlled trial of elective intervention with continuous inflating pressure (CIP) was performed in infants with severe hyaline membrane disease who weighed more than 1000 g at birth. Infants entered the trial if their arterial oxygen tension (PaO2) fell below 60 mmHg while breathing a fractional inspired oxygen concentration (F1O2) greater than 0-95. 11 out of 12 infants in the CIP-treated group and 10 out of 12 in the control group survived. 7 treated and 6 control infants required mechanical ventilation. When CIP was started the Pao2 of the treated infants increased, and they breathed high concentrations of oxygen for a significantly shorter period than the control infants. During the 31-month duration of the trial 107 other infants with severe hyaline membrane disease were admitted who did not meet the criteria for entry to the trial. 37 survived after breathing high concentrations of oxygen (F1O2 greater than 0-60) spontaneously without any ventilatory assistance, and the remaining 70 infants were already being ventilated on their arrival in the unit, usually because they had required mechanical ventilation during transfer from other hospitals. The neonatal survival rate for those infants born in this hospital during the study period was 88% (50 out of 57 infants) and for those referred from other hospitals it was 69% (51 out of 74 infants). The maximum further increase in overall survival rate that might have been achieved in our population of infants if CIP had been initiated very early in the course of the illness was 5%--i.e. from 77% (101/131) to 82% (107/131). 相似文献
95.
Gastroduodenoscopy and retrograde cholangiopancreatography has been performed on 25 occasions in 20 children aged between 7 and 16. Radiographs of the clinically relevant duct or ducts were achieved in 96% of attempts, with no complications. The diagnostic information proved useful clinically; in particular it provided a precise map if biliary or pancreatic surgery was being contemplated. Several unexpected congenital duct anomalies were found. This and other recent reports, particularly from Germany, indicate that endoscopic retrograde cholangiopancreatography deserves greater application in children, and can also be used in babies. 相似文献
96.
Christina N Grupcheva MD Jennifer P Craig PhD Trevor Sherwin PhD Charles NJ McGhee PhD FRCOphth FRACO 《Clinical & experimental ophthalmology》2001,29(3):133-137
The purpose of this study was to demonstrate microstructural differences between clinically similar, but aetiologically different, cases of corneal oedema in four subjects. In vivo confocal microscopy highlighted oedema of the basal epithelium, prominent nerve–keratocyte interactions, and typical ‘epithelialization’ of the endothelium in a case of iridocorneal endothelial syndrome; however, a similar microstructural appearance was observed in a case of presumed herpetic disciform keratitis. The latter diagnosis was subsequently revised on this basis. Confocal examination of Fuchs’ endothelial dystrophy demonstrated oedema of the basal epithelium, prominent wing cells, anterior stromal alterations, fibrosis of Descemet’s membrane and a typical ‘strawberry’ appearance of the endothelium. In contrast, in vivo microstructural examination of bilateral keratoconus with hydrops confirmed oedema mainly involving the epithelium and anterior stroma. In vivo confocal microscopy allows the clinician to observe the living cornea at a microstructural level and to better diagnose and differentiate borderline or unusual cases of corneal oedema. 相似文献
97.
W c Hsu Ts Sheen C d Lin C t Tan T h Yeh S y Lee 《Otolaryngology--head and neck surgery》2000,122(3):450-454
This study examined 11,333 rigid endoscopy procedures performed in the Department of Otolaryngology, National Taiwan University Hospital, during a 27-year period from 1970 to 1996. Among these cases, 3217 were performed to remove foreign bodies from the airway (459 cases, 14.3%) and esophagus (2758 cases, 85.7%). Retrospective analysis of these data revealed that peanuts (217 cases) and animal bones (1184 cases) were the most frequent foreign bodies encountered in the airway and esophagus, respectively. The successful rate of removal of these foreign bodies was 99.9% (3213/3217). The complication rate was only 0.2% (8/3217), and the mortality rate was less than 0.1% (2/3217). On the basis of these results, we conclude that foreign bodies in the airway and esophagus can be removed safely under direct visualization through rigid endoscopy with relatively few complications. A significant finding in this study is the declining trend in the number of cases in recent years. Despite the decline in the number of procedures, endoscopic removal of foreign bodies remains as a vital skill of the aerodigestive tract surgeon. 相似文献
98.
99.
100.
Hasegawa BH; Naimuddin S; Dobbins JT d; Mistretta CA; Peppler WW; Hangiandreou NJ; Cusma JT; McDermott JC; Kudva BV; Melbye KM 《Radiology》1986,159(2):537-543
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone. 相似文献