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Oral hairy leukoplakia is an epithelial lesion of the tongue associated with productive infection by Epstein-Barr virus (EBV). However, no data concerning the pattern of EBV latent gene expression have been reported, and it remains unresolved whether true latent infection occurs in basal cell layers of oral hairy leukoplakia. We have studied six cases of oral hairy leukoplakia using monoclonal antibody immunohistology for EBV latent--EB nuclear antigen (EBNA) 1, EBNA 2 and latent membrane protein 1 (LMP 1); immediate-early (BZLF1); and replicative (EA, VCA, MA) proteins, and for the EBV-receptor (CD21 antigen). EBV DNA was demonstrated by nucleic acid in situ hybridization. Mid- to upper-zone keratinocytes contained EBV DNA and co-expressed EBNA 1, EBNA 2 (5 of 6 cases), LMP 1, BZLF1 protein, EA, VCA and MA. No EBV genome or gene expression could be demonstrated in basal or parabasal cells. Spinous keratinocytes were labelled by anti-CD21 antibodies HB5 and B2, but did not express the EBV-receptor as defined by reactivity with OKB7. The co-expression of latent and replicative infection-associated antigens is striking, indicating possible functional roles for latent proteins during the productive cycle. Our results suggest that oral hairy leukoplakia is caused by repeated direct infection of upper epithelial cells with virus from saliva or adjacent replicatively infected cells, rather than by a latent EBV infection of basal epithelial cells with a differentiation-dependent switch to productive infection as previously proposed.  相似文献   
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Background: This study examines the notion that gastrointestinal endoscopy performed by supervised surgical residents is safe. Methods: We reviewed all gastrointestinal endoscopic procedures performed by surgical residents with faculty supervision for complications and deaths occurring up to 30 days following the procedures. Results: The overall complication rate for 9,201 upper and lower endoscopy procedures was 1.4% and 0.42%, respectively. Overall mortality rate was 0.76% for upper endoscopy and 0.6% for lower endoscopy. No mortality was a direct result of a procedure-related complication. Intestinal perforation, drug overdose, bleeding, and aspiration were the most common procedure-related complications. Each resident completed an average of 75 upper endoscopies and 79 lower endoscopies during their training period. Conclusions: Gastrointestinal endoscopy can be performed safely by surgical residents with appropriate supervision. The higher morbidity and mortality of upper endoscopy are most likely related to the underlying disease rather than the procedure. Awareness of common complications and application of appropriate precautions and instruction are critical for minimizing complications. Received 25 March 1996/Accepted: 24 April 1996  相似文献   
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Nearly 4 million women in the United States were physically hurt by their husbands or boyfriends in 1994. The health and well-being of these women and their children, as well as the women who are overlooked in these statistics, are jeopardized by past and current experiences with abuse within intimate relationships. Strategies for nurses in women's health care settings to screen women for current or past abuse within their intimate personal relationships, guidelines for effective responses to disclosure of abuse, and supportive interventions are described.  相似文献   
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Lynch  DA; Gamsu  G; Ray  CS; Aberle  DR 《Radiology》1988,169(3):603-607
In 260 asbestos-exposed individuals evaluated by means of computed tomography (CT), 43 unsuspected pulmonary masses were found in 27 individuals. The masses included fissural pleural plaques (n = 10), dense fibrotic bands (n = 3), round atelectasis (n = 11), carcinomas (n = 3), and other presumed benign masses (n = 16). The most helpful features in the diagnosis of rounded atelectasis with CT were (a) contiguity to areas of diffuse pleural thickening, (b) a lentiform or wedge-shaped outline, (c) evidence of volume loss in the adjacent lung, and (d) a characteristic "comet tail" of vessels and bronchi sweeping into the margins of the mass. Less advanced areas of focal atelectasis had fewer classic features. Intrafissural pleural plaques were readily identified with high-resolution CT. In asbestos-related masses, the demonstration of stability over time is necessary. Careful interpretation of CT and high-resolution CT features and close surveillance can obviate the need for biopsy in the majority of instances.  相似文献   
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