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The expression of membrane immunoglobulin (mIg) was examined in three cloned MPC11-derived mouse myeloma cell lines. Membrane immunofluorescence studies demonstrated that IgG2b producer cells (P1) had complete IgG molecules, L-chain producer (L1) had only L-chain determinants and nonproducer (NP2) did not have any Ig determinants on the cell surface. An Ig receptor, with characteristics different from B lymphocyte Fc receptor, has been found to be present on secreting cells (P1 or L1), but not on the NP2 cell variant. The data reported in the present paper indicate that the expression of mIg and of the Ig receptor molecule is clearly correlated with the process of secretion. In the light of previous data reported on Ig secretion, a model is proposed which correlates the process of secretion with the expression not only of mIg, but also of the receptor for Ig.  相似文献   
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A review of the experience with 134 consecutive patients with germinal cell testicular neoplasia indicates that definitively accurate staging of the malignancy at presentation is the single most important prognostic factor. Nearly two-thirds of the patients with all types of germinal malignancies survived or died of other causes and the highest survival rates were seen among patients with earlier stages of seminoma. In recent years patients with all types of germinal malignancies of the testis have been treated by radical retroperitoneal lymphadenectomy with enhancement of survivals. Patients with seminoma and non-seminomatous tumors exhibited increased survival rates with node dissection. In 66 consecutive lymphadenectomies the complication rate was less than 14 per cent, with only 1 death related to the operation. Retroperitoneal lymphadenectomy not only affords therapeutic advantage but also provides an opportunity for accurate surgical staging of disease and allows for rational decision relative to additional treatment, radiation therapy or chemotherapy.  相似文献   
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不同波长响应的Y2O2S:Er3+,Yb3+上转换发光材料的光谱特性   总被引:1,自引:0,他引:1  
以Y2O2S为基质材料、Er2O3为激活剂、Yb2O3为敏化剂,采用固相反应法制备Y2O2S:Er3+,Yb3+上转换发光材料.采用X射线粉末衍射分析和荧光光谱分析表征样品的结构和发光性能,并分析上转换发光机理.结果表明:在980 nm和1 550 nm红外光激发下,样品发出源于Er3+的2H11/2→4I15/2、4...  相似文献   
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对某印染厂废水处理站排水进行了回用处理研究.在恒压条件下,采用聚乙烯(PE)中空纤维膜,进行间歇曝气扫流过滤,分析了不同操作方式对超滤速率变化的影响.结果表明曝气在超滤中能够起到防止污染的作用,解除作用于颗粒上的抽吸力后再采用曝气扫流,则能达到更好的扫流效果.周期运行与非周期运行之间的差距较大,按"曝气过滤-暂停-曝气扫流"<"不曝气过滤-暂停-曝气扫流"<"连续曝气扫流"的顺序阻力增大,因此采用周期运行方式在一定程度上可以恢复超滤速率.印染废水过滤中,在抽吸压力小于0.08 MPa的范围内,可以不考虑沉积物的压缩性.  相似文献   
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To examine the effects of recombinant human erythropoietin (rHuEPO) on hospital utilization, hospital costs, and Medicare reimbursements for hospital care, a longitudinal, matched cohort study was conducted using Medicare claims data of 23,806 Medicare-eligible, dialysis patients who received rHuEPO, did not have a transplant, and were alive for 18 mo or longer and 22,720 controls matched on age, sex, race, cause of ESRD, and dialysis modality. The relative odds (rHuEPO versus control) of admission for all causes and for specific causes over 9 mo, adjusted for admission in the prior 9 mo and the per patient change in total admissions, inpatient days, hospital costs, and Medicare hospital payments between the prior 9-mo period and the subsequent 9-mo period was examined. The adjusted relative odds (95% confidence interval) of admission (rHuEPO versus control) was: higher and statistically significant for all causes, 1.08 (1.03 to 1.14); seizure, 1.52 (1.28 to 1.75); vascular access revision, 1.11 (1.06 to 1.17), and heart failure, 1.17 (1.09 to 1.26); higher but not statistically significant for angina, 1.09 (0.99 to 1.20) and stroke, 1.08 (0.86 to 1.31); and lower but not statistically significant for myocardial infarction, 0.91 (0.72 to 1.10); peripheral vascular disease, 0.81 (0.60 to 1.02); anemia, 0.86 (0.56 to 1.17); and depression, 0.89 (0.37 to 1.40). The mean change per 1,000 patients in admissions was less by 38 (P = 0.03) because of fewer readmissions, and in days was 1,309 less (P < 0.001), for patients treated with rHuEPO versus controls. The mean change per patient in hospital costs was $371 less and was statistically significant (P = 0.03) and in Medicare hospital payments was $132 less but was not statistically significant (P = 0.43) for patients treated with rHuEPO versus controls. rHuEPO was associated with an increase in the probability of hospital admission (particularly admissions potentially related to adverse effects) but a decrease in readmissions, overall admissions, hospital days, and cost to hospitals in this cohort of patients surviving for 18 mo. Although not realized short term, Medicare savings from potential rHuEPO-related reductions in hospital care may be long term through future adjustments in diagnosis-related group-based hospital payment.  相似文献   
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