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B-cell lymphoproliferative disorders are rare but serious complications of solid organ and bone marrow transplantation. We report that these tumors frequently express the CD-20 antigen, and immunotherapy directed at this antigen may be a well-tolerated and effective treatment.  相似文献   
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The incidence of primary liver cancer in Chinese, Japanese, and Filipino migrants to the United States and their descendants is compared with that of United States-born Whites. Incident liver cancer cases were ascertained between 1973 and 1986 from population-based cancer registries serving the San Francisco/Oakland (CA) metropolitan area, 13 counties of western Washington, and Hawaii. The population of these three areas, with regard to age, race, and country of birth, was estimated from a special tabulation of the 1980 US census. Rates of primary liver cancer were higher for men born in Asia than Asian men born in the US, who, in turn, had higher rates than did US Whites (respective annual rates per 100,000: Chinese, 26.5 and 9.8; Japanese, 16.5 and 6.6; Filipinos, 11.4 and 6.5; US Whites, 3.4). Among Asian American women, the trends were not as consistent (respective annual rates per 100,000: Chinese, 2.2 and 3.7; Japanese, 1.9 and 1.4; Filipino, 2.6 and 0; US Whites, 1.1). In general, liver cancer incidence among Asian Americans was lower than among residents of Asia. These findings are compatible with substantial variation among Asians in the prevalence of one or more etiologic factors for liver cancer, such as hepatitis-B infection and aflatoxin consumption, in relation to residence and place of birth.Dr Rosenblatt is with the Department of Community Health, University of Illinois, Champaign, IL, USA. Drs Weiss and Schwartz are with the Department of Epidemiology, University of Washington, and Program in Epidemiology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. Address correspondence to Dr Rosenblatt, Department of Community Health, 121 Huff Hall, University of Illinois at Urbana-Champaign, 1206 South Fourth Street, Champaign, IL 61820, USA. This research was supported by grant numbers R35CA39779 and T32CA09168 from the US National Cancer Institute.  相似文献   
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An Epstein-Barr virus-transformed B-cell line derived from a patient with severe combined immunodeficiency who died of a lymphoreticular malignancy has been characterized. The line derived from bone marrow cultures and designated DV-1 shows surface and cytoplasmic IgM and staining with fluorescent monoclonal antibodies against immunoglobulin heavy and light chains mu, delta, and kappa, Dr, and several other B-cell surface antigens. DV-1 secretes IgM kappa and demonstrates monoclonality on analysis of immunoglobulin heavy and light chain gene rearrangement patterns. Incubation with either phytohemagglutinin or pokeweed mitogen failed to cause significant stimulation of proliferation of DV-1 and another EBV-transformed B-cell line derived from an immunologically normal host (LA-350), whereas incubation with Staphylococcus aureus Cowan strain 1 led to significant inhibition of DV-1 and LA-350. Rabbit IgG antibody specific for human immunoglobulin mu-chains produced a dose dependent stimulation of both lines. The responses of DV-1 and LA-350 to mitogens and anti-mu were not as high as those of normal peripheral blood lymphocytes. This spontaneously derived Epstein-Barr virus-transformed B-cell line from a patient with severe combined immunodeficiency demonstrated functional characteristics similar to a B-cell line derived from an immune competent host. While these cells spontaneously incorporate 200 times more thymidine than normal resting peripheral blood lymphocytes, they retain their ability to be modulated by antiimmunoglobulin, and staphylococcal Cowan strain 1, but are unresponsive to the effects of B-cell growth factor.  相似文献   
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Rosenblatt  Laurie 《JAMA》2005,293(10):1171
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BACKGROUND: There is an increasingly recognized association between pulmonary arteriovenous malformations (PAVM) and cerebral ischemia, frequently attributed to paradoxical embolization. PAVM occur in 20 to 30% of the hereditary hemorrhagic telangiectasia (HHT) population. OBJECTIVE: To evaluate the risk determinants for cerebral ischemia and neurologic manifestations in patients with PAVM. METHODS: A retrospective cross-sectional study was performed on consecutive patients admitted between 1988 and 1992 for treatment of PAVM. The number of PAVM, feeding artery (FA) diameters, and aneurysmal sizes were determined by pulmonary angiography. Patients were categorized as having single or multiple PAVM with an FA diameter of > or = 3 mm. History, examination, and cerebral imaging studies were used to determine the prevalence of neurologic manifestations. Patients were defined as having cerebral paradoxical embolization if there was radiologic evidence of cortical infarction. RESULTS: There were 75 cases: 26 single PAVM and 49 multiple PAVM. Cortical infarction was present in 14% of patients with single PAVM. Patients with multiple PAVM had a greater prevalence of any infarction (OR 3.2; 95% CI, 1.2 to 9.44, p = 0.030), cortical infarctions (OR 2.3; 95% CI, 0.58 to 9.2, p = 0.230), subcortical infarctions (OR 2.1; 95% CI, 0.58 to 7.95, p = 0.249), abscesses (OR 2.3; 95% CI, 0.46 to 11.94; p = 0.295), and seizures (OR 6.4, 95% CI 0.77 to 53.2, p = 0.054). Patients with multiple PAVM had markedly greater odds of having any clinical or radiologic evidence of cerebral ischemic involvement (OR 4.5; 95% CI, 1.47 to 14; p = 0.008). CONCLUSION: There is a strong association between single PAVM and various neurologic manifestations. The prevalence is greater for patients with multiple PAVM, suggesting increased predisposition for paradoxical embolization with a greater number of malformations.  相似文献   
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