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71.
The antigen-presenting environment in normal and human papillomavirus (HPV)-related premalignant cervical epithelium 总被引:13,自引:0,他引:13
The activation of HPV-specific T cells within the cervical microenvironment is likely to play an important part in the natural history of cervical intraepithelial neoplasia (CIN). The extent and the type of T cell activation will depend critically on the expression of MHC, costimulatory cell surface molecules and cytokines by keratinocytes and Langerhans cells within the cervical lesion. Expression of MHC class II (HLA-A-DR and -DQ), costimulatory/adhesion molecules (CD11a/18, CD50, CD54, CD58 and CD86) and cytokines (tumour necrosis factor-alpha (TNF-alpha) and IL-10) was therefore investigated by immunohistochemistry in normal squamous epithelium (n = 12), low-grade (n = 23) and high-grade (n = 18) squamous intraepithelial lesions of the cervix. CIN progression was associated with de novo expression of HLA-DR and CD54, and increased expression of CD58 by keratinocytes. However, significantly, there was no expression of any adhesion/costimulation molecule by epithelial Langerhans cells in any cervical biopsy studied. Furthermore, TNF-alpha, a potent activator of Langerhans cells, was expressed constitutively by basal keratinocytes in normal cervix (12+/12). but expression of this cytokine was absent in a number of CIN samples (20+/23 for low-grade, 12+/18 for high-grade CIN). Conversely, the suppressive cytokine IL-10 was absent in normal epithelium (0+/12), but was up-regulated in a number of CIN lesions (12+/23 for low-grade; 8+/18 for high-grade CIN). The restricted expression of costimulation/adhesion molecules and the nature of the cytokine microenvironment within the epithelium may act to limit effective immune responses in some CIN lesions. 相似文献
72.
We report on a patient with trisomy 18 syndrome and tetrasomy 18p. The case indicates that the presence of an isochromosome i(18p) can mimic complete trisomy 18 syndrome. 相似文献
73.
74.
CDX-2 immunostaining in primary and secondary ovarian carcinomas 总被引:2,自引:0,他引:2
AIMS: To assess the value of homeobox protein CDX-2 expression in the distinction between primary ovarian carcinomas and carcinomas metastatic to the ovary. METHODS: CDX-2 expression was assessed by immunohistochemistry in 120 serous, 68 endometrioid, 24 clear cell, and 16 mucinous carcinomas of the ovary. In addition, CDX-2 immunoreactivity was investigated in 20 metastases from adenocarcinomas to the ovary (15 of colorectal, two of gastric, one of appendiceal, one of pancreatic, and one of cervical origin) and their corresponding primary tumours. RESULTS: Almost all of the primary ovarian carcinomas lacked immunoreactivity for CDX-2. In contrast, 14 of the 16 metastases to the ovary from intestinal primaries showed CDX-2 immunoexpression. CONCLUSION: CDX-2 is a useful marker for differentiating primary ovarian carcinoma from carcinomas metastatic to the ovary. 相似文献
75.
The lung in cystic fibrosis. A quantitative study including prevalence of pathologic findings among different age groups. 总被引:12,自引:0,他引:12
The autopsies of 82 patients with cystic fibrosis were reviewed with respect to pathologic changes in the lungs and their respective prevalence among different age groups. Although bronchitis, mucopurulent plugging, and bronchopneumonia were almost universally present among children of all ages, epithelial metaplasia and bronchiectasis were rarer among infants and progressively more prevalent in older age groups. Emphysema was absent in patients under two years of age and affected 11 per cent of the patients two to six years of age and 40 per cent of the patients older than six years, but was never of a severe degree by the point count method. Pulmonary hemorrhage, although uncommon, was usually associated with prominent arterial vessels in walls of bronchiectatic airways. Quantitative assessment of bronchial glands revealed Reid indices significantly higher in patients with cystic fibrosis when compared to noncystic fibrosis patients, but there was no increase in these indices with the age of the patients. Glandular hypertrophy, predominance of mucous acini within glands, and goblet cell hyperplasia of the bronchial mucosa all suggest an explanation for the copious mucous secretion of patients with cystic fibrosis. However, it was not possible to ascertain whether these findings reflect a general exocrine defect of such patients or whether they were merely a response to chronic airway infection, even though the latter is a more plausible assumption. 相似文献
76.
Robert H Friedman Sandhya Wahi-Gururaj Joel Alpert Howard Bauchner Larry Culpepper Timothy Heeren Allen Singer 《Academic medicine》2004,79(11):1095-1102
PURPOSE: To understand the views of U.S. medical school deans about their primary care faculties. METHOD: In 2000, the authors mailed a questionnaire containing 43 multipart items to deans of 130 U.S. allopathic medical schools. The questionnaire assessed the deans' attitudes about and evaluation of primary care at their school and their school's efforts to strengthen it. Deans were asked to compare family medicine, general internal medicine, and general pediatrics with nonprimary care clinical departments at their schools. RESULTS: Of the 83 (64%) deans who responded, 82% reported their school had departments or divisions of family medicine, general internal medicine, and general pediatrics. Deans rated general internal medicine and general pediatrics higher than nonprimary care faculty on clinical expertise and productivity (p < .001) and family medicine equivalent to nonprimary care faculty. Deans rated all three primary care faculties superior to nonprimary care faculty for teaching skills (p < .001) and programs (p < .05), but lower than nonprimary care disciplines for research productivity (p < .01) and revenues (p < .001). They rated family medicine and general pediatrics lower for research skills (p < .001), but 73% of deans stated research was equally important for primary care and nonprimary care departments. Deans considered overall financial resources to be equivalent for primary care and nonprimary care departments, but 77% of deans felt primary care departments or divisions needed financial support from the medical school to survive. Most deans attempted to strengthen primary care by changing the curriculum to promote primary care and by providing financial support. CONCLUSIONS: Deans ranked primary care faculty high on clinical and teaching measures. Although they considered research to be an important activity for primary care faculty, they evaluated it low relative to nonprimary care departments. 相似文献
77.
A Singer S Thompson C Kraiuhin E Gordon G Howe A Howson R Meares 《Psychotherapy and psychosomatics》1987,47(3-4):181-189
The Illness Behaviour Questionnaire was used to determine whether three groups of patients who had presented with multiple symptoms in different treatment settings (Briquet's syndrome, post-viral fatigue syndrome, and a heterogeneous general practice group) could be differentiated from one another and from a mixed group of psychiatric patients on the basis of their abnormal illness behaviour. All groups completed a version of the Perley and Guze diagnostic criteria for Briquet's syndrome. The three groups presenting with multiple symptoms were more similar to each other than to the psychiatric patients. The results suggest that patients presenting with multiple symptoms include similar populations of patients who are poorly distinguished using current schemes of classification. 相似文献
78.
Choriocarcinoma has been described as the most frequent subtype of mediastinal germ cell tumors showing trophoblastic differentiation. We report a unique case of a placental site trophoblastic tumor, which developed in the mediastinum of a 14-year-old boy 2 years after the resection of a mature teratoma. The recurrent tumor was composed of a grossly hemorrhagic and necrotic mass. Histologically, diffusely infiltrating large polygonal cells with focal nodular growth and a teratomatous part containing mature intestinal, respiratory, and squamous epithelium with adjacent cutaneous adnexal structures were found. The typical morphologic features included vessel wall infiltration by the neoplastic cells with fibrinoid deposits and geographic necroses within the tumor masses. Characteristic diffuse positivity for melanoma cell adhesion molecule and human leucocyte antigen G was found on immunohistochemical investigation, confirming the diagnosis of placental site trophoblastic tumor. The patient died 1 year later after polychemotherapy. The outcome of this rare tumor is similar to the reported poor clinical outcome in patients with mediastinal choriocarcinomas. 相似文献
79.
E. E. Emeson V. Manaves T. Singer M. Tabesh 《The American journal of pathology》1995,147(6):1749-1758
Although there is abundant clinical evidence that the consumption of alcohol (ethanol) in moderate amounts has a protective effect on coronary artery disease, the mechanism of this effect is not understood. The prevailing theory supported by a limited number of clinical and experimental animal studies indicates that the ability of alcohol to elevate serum high-density lipoprotein cholesterol levels is an important mechanism. Although there have been a large number of studies on the effects of alcohol on serum lipoprotein and apolipoproteins on coronary artery disease, there have been very few that have, at the same time, looked directly and systematically at its effects on the histopathological development of atherosclerotic lesions. In the following studies we employed the hyperlipidemic C57BL/6 female mouse model and formulated an all liquid high fat atherogenic diet to provide the mice with the 3% or 6% alcohol. After 22 weeks on this diet, alcohol markedly inhibited the development of fatty streak atherosclerotic lesions in a dose-dependent fashion. Surprisingly, there was a dose-dependent decrease in plasma high-density lipoprotein cholesterol values, which suggests that high-density lipoprotein alterations play little or no role in the amelioration of atherosclerosis in this model. 相似文献
80.
Discussions of adjunctive behavior still largely refer to polydipsia induced by food delivery schedules to food deprived animals. In the present experiment polydipsia was induced when socially isolated monkeys housed in barren home cages were exposed to scheduled deliveries of film and scheduled viewing of other monkeys. These data suggest the greater generality and complexity of adjunctive behaviors and show that schedule-induced polydipsia cannot be regarded as an artifact of food associated drinking. 相似文献