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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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目的:消极情绪对心脏预后具有不利影响。探讨社会抑制(在社会相互接触中抑制自我表现)是否可调节消极情绪对经皮冠状动脉介入(PCI)治疗后临床预后的作用。方法和结果:来自RESEARCH登记(鹿特丹的Erasm us医疗中心)的875例患者在PCI后6个月完成了抑郁、焦虑、消极(一般为消极情绪)以及社会抑制量表的评估。终点为评估后9个月发生的主要不良心脏事件犤M ACE;死亡、心肌梗死、冠状动脉搭桥术(CABG)或PCI犦。共发生100例次M ACE;与消极评分高而抑制评分低的患者(13/136,10%)相比,消极情绪及抑制评分均较高的患者(38/254,15%;P=0.018…  相似文献   
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Background: The purpose of this study was to evaluate the tumor characteristics and treatment associated with an improved overall survival in patients with adenocarcinoma of the small intestine. Methods: The records of all patients with primary adenocarcinoma of the small bowel seen between January 1971 and December 1991 were reviewed retrospectively. The study comprised 38 patients, 22 (58%) with duodenal tumors, 11 (29%) with jejunal tumors, and five (13%) with ileal tumors. Results: Although not statistically significant, the patients with duodenal adenocarcinoma lived longer than the patients with jejunal or ileal lesions (p=0.77). The overall survival was 23% and seemed to correlate best with absence of lymph node metastases (p=0.04) and pancreaticoduodenectomy for localized duodenal tumors (p=0.04). The patient's age, duration of symptoms, disease-free interval, tumor location, type of recurrence, and histologic grade did not significantly influence survival. Conclusions: The lethality of small-intestinal adenocarcinoma appears to be related to a delay in diagnosis and treatment. When a definitive surgical procedure is performed before lymph node metastases appear, the patient's chance for long-term survival is greatly improved.Presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993.  相似文献   
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BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited human kidney disease and is caused by germline mutations in PKD1 (85%) or PKD2 (15%). It has been estimated that around 1% of tubular cells give rise to cysts, and cell hyperproliferation has been noted to be a cardinal feature of cystic epithelium. Nevertheless, it is uncertain whether the increase in proliferative index observed is an early or late feature of the cystic ADPKD kidney. METHODS: Two Pkd2 mouse mutants (WS25 and WS183) have been recently generated as orthologous models of PKD2. To determine the effect of Pkd2 dosage on cell proliferation, cyst formation and renal fibrosis, we studied renal tissue from Pkd2(WS25/WS25) and Pkd2(+/-) mice by histological analysis. We also examined the proliferative index in archival nephrectomy tissue obtained from patients with ADPKD and normal controls. RESULTS: The proliferative index of non-cystic tubules in Pkd2 mutant mice as assessed by proliferating cell nuclear antigen and Ki67-positive nuclei was between 1-2%, values 5-10 times higher than control tissue. Similarly, the proliferative index of non-cystic tubules in human ADPKD kidneys was 40 times higher than corresponding controls. In Pkd2 mutant mice, significant correlations were found between the fibrosis score and the mean cyst area as well as with the proliferative index. Of significance, proliferating tubular cells were uniformly positive for polycystin-2 expression in Pkd2(+/-) kidney. CONCLUSION: These results suggest that an increase in cell proliferation is an early event preceding cyst formation and can result from haploinsufficiency at Pkd2. The possible pathogenic link between tubular cell proliferation, interstitial fibrosis and cyst formation is discussed.  相似文献   
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The case report describes a distinct variant of non-REM (Rapid Eye Movement) arousal parasomnia, sleepwalking type, featuring repetitive abrupt arousals, mostly from slow-wave sleep, and various automatisms and semi-purposeful behaviours. The frequency of events and distribution throughout the night presented as a continuous status of parasomnia (' status parasomnicus '). The patient responded well to treatment typically administered for adult NREM parasomnias, and after careful review of the clinical presentation, objective findings and treatment outcome, sleep-related epilepsy was ruled out in favour of parasomnia.  相似文献   
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Dysembryoplastic neuroepithelial tumor in the left lateral ventricle.   总被引:3,自引:0,他引:3  
Extracortical location of dysembryoplastic neuroepithelial tumor (DNT) is rare. We present a case of DNT localized in the left lateral ventricle of a 21-year-old female patient. Magnetic resonance imaging of the brain showed a round mass lesion in the floor of the anterior horn of the left lateral ventricle. The lesion was hypointense on T (1)-weighted images and slightly hyperintense on T (2)-weighted images without contrast enhancement. Total removal of the yellowish-white colored soft tumor was performed through a transcallosal approach. Histologically, the tumor was of simple type of DNT that was composed of small oligodendrogliocytes clustered tightly about perivascular spaces with neurons floating in mucoid pools showing an eosinophilic fibrillary matrix in the background. The recognition of DNT with an unusual location in lateral ventricle has therapeutic and prognostic significance since DNT is curable by surgical excision and radiation therapy is of no obvious benefit.  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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