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31.
One hundred and seven smears demonstrating a low-grade squamous intraepithelial lesion (LSIL) were analyzed for features predicting subsequent biopsy confirmation. Twelve (29%) of 41 smears showing few LSIL cells were biopsy confirmed compared to 33 (60%) of 55 containing an intermediate number of LSIL cells and 9 (82%) of 11 displaying many LSIL cells (P < 0.002). Thirty-seven (47%) of 78 smears showing mainly condylomatous atypia (CA), 7 (54%) of 13 revealing predominantly cervical intraepithelial neoplasia 1 (CIN 1), and 10 (63%) of 16 displaying both CA and CIN 1 were histologically confirmed (N.S.). Biopsy confirmation was obtained in 35 (65%) of 54 women whose repeat smears obtained at colposcopy demonstrated SIL compared to four (15%) of 26 patients whose repeat smears were normal or contained atypical squamous cells of undetermined significance (P < 0.001). These results suggest that the number of diagnostic cells in an LSIL smear predicts biopsy confirmation and affirm the validity of combining CA and CIN 1 under the category of LSIL in the Bethesda System. © 1994 Wiley-Liss, Inc.  相似文献   
32.
Staphylococcus aureus enterotoxin B (SEB) was added to explants of fetal human intestine in organ culture or administered into the lumen of fetal small intestine prior to culture. Both routes produced a massive increase in lamina propria T cells expressing Vβ33, and to a lesser extent, those expressing Vβ5 and Vβ12. SEB-activated lamina propria T cells produced interleukin-2 and interferon-Y and T cell activation was accompanied by tissue damage, which was inhibited by FK506.  相似文献   
33.
The relationship between the numerical aberrations of chromosome 7 in interphase cells and the clinicopathological behavior of breast tumors was investigated in 51 touch imprinted preparations of breast tumors. Using fluorescence in situ hybridization with a chromosome 7-specific DNA probe, the fluoresceinisothiocyanate (FITC) spots mean and the representative copy number of each breast tumor were examined. The FITC spots mean (2.34) of 40 breast cancers increased compared with that of 11 benign lesions (1.98) (P < 0.02). The FITC spots mean tended to increase with the advancing stage and tumor size of the breast cancer. The FITC spots mean in the case with metastasis was also of a higher value than that without metastasis (P < 0.01). Furthermore, the existence of trisomy or over-trisomy of the copy number was related to the advancing stage and tumor size (P < 0.05 and P < 0.01, respectively). These findings suggest that the FITC spots mean and polysomy of the number of chromosome 7 may be highly predictive for breast tumor aggressiveness.  相似文献   
34.
Summary Two cases of renal epithelial tumours are reported in females aged 46 and 66 years respectively. In spite of the large size of the tumours, neither invasive growth nor metastasis was observed. Histologically, the tumours were composed of immature epithelial cells forming tubules with abortive glomeruloid structures. Electron microscopy of tumour cells revealed poorly developed polarity and intracytoplasmic organelles. They showed similar immunohistochemical reactions to those of developing nephrons, particularly to those of the S-shaped body. The nuclear DNA content of the tumour cells was almost euploid. We conclude that the lesions were epithelial tumours of the kidney histologically mimicking developing renal parenchyma.  相似文献   
35.
Expression of syndecan-1, a cell surface proteoglycan that binds growth factors and extracellular matrix components, was studied in normal and pathological human uterine cervix using immunohistochemical methods. Normal cervical squamous epithelium showed positive staining for syndecan-1 in all cell layers, except the basal cell layer, whereas endocervical columnar epithelium stained weakly. In non-neoplastic reactive lesions, metaplastic squamous cells were positive for syndecan-1, whereas columnar cells showed weak or negative staining. In cervical condylomas, cells showing koilocytotic atypia were positive for syndecan-1. The progression of cervical intraepithelial neoplasia (CIN) grade I to grade III was associated with reduced syndecan-1 expression and localization of syndecan-1 to more superficial cell layers. In squamous cell carcinomas (SCCs), syndecan-1 expression correlated with histological differentiation, being absent from most poorly differentiated tumours. The results suggest that loss of syndecan-1 from atypical cells is an early event during cervical carcinogenesis and show a close association of syndecan-1 expression with preserved epithelial morphology and differentiation.  相似文献   
36.
In conventional mice, the T cell receptor (TCR)αβ+ CD8αα+ and CD8αβ+ subsets of the intestinal intraepithelial lymphocytes (IEL) constitute two subpopulations. Each comprise a few hundred clones expressing apparently random receptor repertoires which are different in individual genetically identical mice (Regnault, A., Cumano, A., Vassalli, P., Guy-Grand, D. and Kourilsky, P., J. Exp. Med. 1994. 180: 1345). We analyzed the repertoire diversity of sorted CD8αα and CD8αβ+ IEL populations from the small intestine of individual germ-free mice that contain ten times less TCRαβ+ T cells than conventional mice. The TCRβ repertoire of the CD8αα and the CD8αβ IEL populations of germ-free adult mice shows the same degree of oligoclonality as that of conventional mice. These results show that the intestinal microflora is not responsible for the repertoire oligoclonality of TCRαβ+ IEL. The presence of the microflora leads to an expansion of clones which arise independently of bacteria. To evaluate the degree of expansion of IEL clones in conventional mice, we went on to measure their clone sizes in vivo by quantitative PCR in the total and in adjacent sections of the small intestine of adult animals. We found that both the CD8αα and the CD8αβ TCRαβ IEL clones have a heterogeneous size pattern, with clones containing from 3 × 103 cells up to 1.2 × 106 cells, the clones being qualitatively and quantitatively different in individual mice. Cells from a given IEL clone are not evenly distributed throughout the length of the small intestine. The observation that the TCRαβ IEL populations comprise a few hundred clones of very heterogeneous size and distribution suggests that they arise from a limited number of precursors, which may be slowly but continuously renewed, and undergo extensive clonal expansion in the epithelium.  相似文献   
37.
目的探讨宫颈不典型鳞状上皮,低度鳞状上皮内病变(ASCUS/LSIL)的临床意义及处理方法。方法对中国医学科学院肿瘤医院2004~2006年妇科门诊用TCT(宫颈液基细胞学)的方法检出的254例ASCUS/LSIL以病理结果为金标准进行回顾性分析,其中136例进行了阴道镜检查。结果在140例ASCUS中,宫颈上皮内瘤变(CIN)病变占51.5%,其中高度病变占22.9%,114例LSIL中CIN病变占59.6%,其中高度病变占30.7%,两组资料比较差异无统计学意义,P〉0.05。其中136例中阴道镜诊断炎症47例,低度宫颈上皮内病变53例,高度宫颈上皮内病变36例及病理检查结果炎症55例,低度宫颈上皮内病变41例,高度宫颈上皮内病变40例,阴道镜与病理对照进行了~致性检验,Kappa=0.314,U=0.064,P〈0.05,一致性好。病理证实人乳头状瘤病毒(HPV)阳性的妇女中CIN发生率79%(67/84),而HPV阴性者中CIN发生率43.5%%(74/170),结果显示两组资料比较差异有统计学意义,X^2=29.88,P〈0.05。本组资料中年龄在35~55岁的妇女占83.5%与HPV阳性的妇女年龄高峰一致。结论对ASCUS的患者应与LSIL同样重视,立即进行阴道镜检查以避免22.9%的高度病变的患者漏诊或失访,对35~55岁的HPV感染的妇女应更加重视。  相似文献   
38.
39.
The results of several retrospective studies allow us to conclude that the detection of fundic gland polyps (Elster's cysts) is associated with an increased incidence of colorectal tumors. In this survey, we present the results of a prospective study investigating such a possible relationship. A total of 144 patients were investigated, of whom 80 had fundic gland polyps of the gastric corpus mucosa. Sixty-four of these patients underwent a colonoscopy, whereas the other 64 patients belonged to a sex- and age-matched control group with no fundic gland polyps. In the group with known fundic gland polyps, colorectal neoplasias were found in 29 (45.3%) patients. Eight of these patients had (12.5%) adenocarcinomas, 3 (4.7%) had high-grade intraepithelial neoplasia, and 18 (28.1%) had tubular adenomas. In one patient, a synchronous carcinoma of the rectum and the colon was detected. In comparison, 6 patients of the control group (9.3%) developed tubular adenomas and 9 (14.1%) had hyperplastic polyps of the colonic and rectal mucosa. Our results suggest that it is necessary to conduct a careful diagnostic work-up of the colon in patients with gastric fundic gland polyps.  相似文献   
40.
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