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71.
Non-Hodgkin's lymphoma (NHL) is the most common human immunodeficiency virus (HIV)-associated malignancy in hemophiliacs. We studied the incidence and clinicopathologic features of NHL in 3,041 hemophiliacs followed at 18 US Hemophilia Centers between 1978 and 1989. Of the 1,295 (56.6%) who were HIV(+), 253 (19.5%) developed acquired immunodeficiency syndrome (AIDS), of whom 14 (5.5%) developed NHL. Three NHL occurred in HIV(-) hemophiliacs, for a 36.5-fold greater risk in HIV(+) than HIV(-) hemophiliacs (P < .001). The NHL incidence rate was 29-fold greater than in the US population by Surveillance, Epidemiology, and End Results (SEER) estimates (P < .001). Between 0 and 4 lymphomas have been observed per year between 1978 and 1989. At presentation 13 (92.9%) of the HIV(+) NHL were extranodal. Ten were stage IV, 1 stage II, and 3 stage IE. Ten (71.4%) were high-grade, 3 (21.4%) intermediate-grade, and 1 (7.1%) was a low-grade B-cell lymphoma. Epstein-Barr virus (EBV) DNA was detected in 36% by in situ hybridization, including one central nervous system (CNS) lymphoma. The mean CD4 cell count at NHL diagnosis was 64/mm3, the mean latency from initial HIV infection was estimated to be 59 months, and the median survival was 7 months. The incidence of basal cell carcinoma in HIV(+) hemophiliacs was 18.3-fold greater than in HIV(-) hemophiliacs (P < .001) and 11.4-fold greater than in the US population (P < .001). In conclusion, incidence rates of NHL and basal cell carcinoma in HIV(+) hemophiliacs are significantly increased over rates in HIV(-) hemophiliacs and over rates in the US population. Clinicopathologic presentation of NHL in HIV(+) hemophiliacs is similar to that in HIV(+) homosexual men.  相似文献   
72.
This article presents an overview of the work of the New Brunswick Health Council (NBHC) since its creation by exploring its mandate and by presenting its different initiatives and publications as they relate to the NBHC's areas of work: population health, care experience, sustainability, and citizen engagement.  相似文献   
73.
Downing  JR; Grossi  CE; Smedberg  CT; Burrows  PD 《Blood》1986,67(3):739-744
A 75-year-old man with hairy cell leukemia (HCL) was found to have an immunoblastic lymphoma of the small bowel. Immunologic and genotypic characterization of these neoplasms revealed both the HCL and the immunoblastic lymphoma to be of the B cell lineage. The HCL expressed the HCL-associated antigens detected by the monoclonal antibodies HC-1 and HC-2, whereas the immunoblastic lymphoma failed to react with these antibodies. In addition, surface immunoglobulin light chains could not be accurately determined for the hairy cells, whereas the immunoblastic lymphoma was shown to express only kappa immunoglobulin light chains. These immunophenotype differences were compatible with either the clonal evolution of the HCL into the immunoblastic lymphoma or a separate clonal origin for these two neoplasms. An analysis of tumor DNA by Southern blot hybridization revealed different heavy-chain and kappa light-chain gene rearrangements in these two malignancies. Thus the occurrence of the large cell lymphoma most likely represents the emergence of a second clonally unrelated B cell malignancy.  相似文献   
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[摘要] 目的 探讨肺癌16层螺旋CT伪彩成像肿瘤红色色彩程度与其Ki-67蛋白表达的关系。方法 25例肺癌行16层螺旋CT增强扫描及肿瘤病灶VR伪彩成像,对每个肿瘤病灶进行免疫组化Ki-67蛋白表达检测。用肿瘤VR伪彩成像红色色彩程度代表肿瘤强化状况,分析肺癌病灶VR伪彩成像红色色彩程度与肿瘤Ki-67蛋白表达关系。结果 VR伪彩成像重度红色色彩肺癌5例,中度红色色彩肺癌8例,轻度红色色彩肺癌9例,无红色色彩肺癌3例。13例重、中度红色色彩肺癌强化增加CT值为26.32±9.17Hu,肿瘤Ki-67蛋白表达阳性率为69.23%。12例轻及无红色色彩肺癌强化增加CT值为10.87±4.257Hu,肿瘤Ki-67蛋白表达阳性率为33.33%。重、中度色彩组与轻或无色彩组肺癌Ki-67蛋白表达比较差异有显著性。结论 肺癌CT伪彩成像红色色彩程度与肿瘤Ki-67蛋白表达有一定相关性,可初步反映其Ki-67表达状况。  相似文献   
76.

BACKGROUND.

Endometrial cytology sampling devices for direct uterine sampling have been shown in previous studies to be a reliable and relatively painless method for detecting endometrial lesions. The purpose of the current study was to determine the performance characteristics of endometrial cytology for the detection of malignancy and atypical hyperplasia using liquid‐based cytology specimens collected with the Tao brush sampler.

METHODS.

Brushings of the endometrial cavity were obtained from 139 hysterectomy specimens before routine histopathologic evaluation. Cytology specimens were fixed in PreservCyt and processed using ThinPrep technology. Cytology diagnoses were classified as nondiagnostic, negative, atypical, or positive for malignancy. Histopathologic findings were used as the gold standard for determining the performance characteristics of cytology.

RESULTS.

Histopathologic results from the 139 patients included 81 (58%) endometrial cancers, 7 (5%) complex hyperplasias with atypia, 2 (1%) complex hyperplasias without atypia, and 49 (35%) patients with benign histology. The number of specimens diagnosed cytologically as positive, atypical, negative, or nondiagnostic was 60 (43%), 40 (29%), 37 (27%), and 2 (1%) specimens, respectively. The overall sensitivity and specificity of cytology for detecting endometrial cancer and atypical hyperplasia were 95% and 66% when atypical cytology specimens were considered positive.

CONCLUSIONS.

The results of the current study indicate that direct endometrial sampling by liquid‐based endometrial cytology collected with the Tao brush sampler produces specimens that contain cellular material that may be identified as endometrial cancer or atypical hyperplasia. Both atypical and positive cytology diagnoses are indicators for triage to more specific methods of diagnosis. Cancer (Cancer Cytopathol) 2008. © 2008 American Cancer Society  相似文献   
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79.
带红系增强子的人β珠蛋白基因在转基因小鼠中的表达   总被引:1,自引:0,他引:1  
带红系增强子的人β珠蛋白基因在转基因小鼠中的表达李政刘德培刘庆辉郭志晨章秋珩李志杰贾佩臣梁植权β41/42是印度次大陆、东南亚及我国南方常见的一种血红蛋白病,纯合子呈严重的β-地中海贫血。本实验旨在建立带红系,增强子5′HS2的人β41/42珠蛋白基...  相似文献   
80.
In infants, the major components of the innate immune system appear weakened, and it has been shown that both polymorphonuclear neutrophil (PMN) production and function are immature. This study was conducted to assess the expression of a number of receptors important to normal PMN function and the integrity of PMN degranulation in cord blood and in uninfected children of varying ages born to human immunodeficiency virus type 1 (HIV-1) seropositive mothers. Although the expression of l-selectin (CD62L) on PMN did not differ between the infants aged 12, 15 and 18 months, the expression of the interleukin-8 (IL-8) receptors CXCR1 and CXCR2, and the complement 5a (C5a) receptor CD88 displayed a similar pattern, with the highest levels expressed on PMN from infants in the 12 month old age group, and declining with age. It was also observed that PMN from a substantial proportion of the younger infants were unresponsive to a variety of stimuli including IL-8, C5a, stromal cell-derived factor (SDF)-1alpha, SDF-1beta, and phorbol 12-myristate 13-acetate (PMA), with the proportions of children showing positive (adult-like) PMN degranulation responses increasing with age. Exposure to HIV-1 did not appear to be the cause of impaired degranulation responses, since a similar proportion of cord blood PMN from uninfected infants born to HIV-1 infected and HIV-1 uninfected mothers were unresponsive. The altered expression of these important receptors and inefficient agonist-induced degranulation in early life may contribute to the increased susceptibility of infants to secondary microbial infections.  相似文献   
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