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531.
目的:体外分离培养并鉴定人外周血树突状细胞,并观察其抗原呈递功能。方法:实验于2005-05/2006-11在南方医科大学南方医院肿瘤中心生物治疗实验室完成。从人类白细胞抗原A2表达阳性的健康人外周血中分离获得单个核细胞。培养5h后洗涤贴壁细胞,加入含有10%人AB血清的RPMI1640培养基,及重组人粒细胞-巨噬细胞集落刺激因子和重组人白细胞介素4,于培养的第1,3,6天对树突状细胞的形态、表型进行分析,并定期检测树突状细胞的纯度与得率。抽取与以上树突状细胞不同来源的其他健康人外周血。经淋巴细胞分离液分离后,获取非贴壁细胞,用含10%人AB血清的1640培养基重悬,加入白细胞介素2继续孵育6d,作为同种异体T淋巴细胞。将树突状细胞分为两组,一组按常规方法培养6d,另一组在培养至第5天时加入黑色素瘤抗原基因A3编码的多肽继续培养24h。在经紫外线处理后的96孔板中,分别加入树突状细胞悬液1×104,5×103,2×103,1×103细胞/每孔,以自身T淋巴细胞作为对照,每孔设3个复孔,分别加入1×105淋巴细胞/每孔。评价树突状细胞刺激T淋巴细胞增殖的能力。结果:①单个核细胞体外培养至第6天,可获得大量、90.81%高纯度的树突状细胞,能够较高地表达21.8?1a、99.0%HLA-DR、63.4?80、18.9?83和80.6?86。②将诱导培养6d获得的两组树突状细胞作为刺激细胞,以不同的浓度与同种异体淋巴细胞混合,均可产生增殖反应;经过黑色素瘤抗原基因A3编码的多肽处理的各种比例的树突状细胞,较相应未经黑色素瘤抗原基因A3编码的多肽处理的树突状细胞激发淋巴细胞增殖的能力明显增强,浓度相对较高的树突状细胞刺激效果最明显,能够强烈地激发同种混合淋巴细胞增殖。结论:得到了一群较高程度表达CD83、CD86和HLA-DR分子、体外可强烈激发同种异体T淋巴细胞增殖的树突状细胞群。  相似文献   
532.
A multicenter prospective study was carried out to evaluate whether a vapor-heated factor VIII concentrate transmitted blood-borne viral infections over a surveillance period of 15 months. Thirty-five patients with hemophilia and von Willebrand disease who had never received any blood components were treated. Twenty-eight were analyzed and found not to have non-A, non-B hepatitis. Sera from 20 of these 28 patients were also tested for the antibody to the hepatitis C virus. None had sero-converted during the follow-up period. None of the patients analyzed developed markers of the hepatitis B virus (n = 17) or the human immunodeficiency virus (n = 31). This vapor-heated factor VIII concentrate carries a low risk of transmitting hepatitis and human immunodeficiency virus infection.  相似文献   
533.
BACKGROUND: Cyclosporin A (CsA) is commonly measured by immunoassay techniques that have a limited analytical range. The consequence of this is that low CsA concentrations that may be clinically significant are difficult to measure and that high concentrations require sample dilution, which introduces error and increases cost. More specific assays, such as HPLC, do not have the required turnaround times for busy transplant clinics. METHODS: CsA was measured in whole blood from 180 cardiac and lung transplant recipients by a liquid chromatography--tandem mass spectrometry (MS) assay, and the results were compared with the Dade Behring Emit assay. Proteins were precipitated with acetonitrile containing ascomycin as internal standard. We used isocratic elution on a Supelco CN column (33 x 3.0 mm; 3- microm bead size) with a mobile phase of 65% aqueous acetonitrile containing ammonium acetate (2 mmol/L) and formic acid (1 g/L), at a flow rate of 0.5 mL/min, with a sample injection volume of 6 microL. We used positive-ion electrospray MS to monitor the ammonium adducts of the compounds of interest decomposing under controlled conditions to the most dominant fragments of the individual molecules. Calibration curves used linear least-squares regression with 1/x weighting. RESULTS: Maximum sensitivity was obtained by monitoring fragmentation of the ammonium adducts m/z 1220-->m/z 1203 for CsA and m/z 809-->m/z 765 for ascomycin. Sample throughput, including preparation time, was 30 samples in 1.5 h with an injection-to-injection cycle time of 1.5 min. The calibration curve was linear to 5000 microg/L, with a detection limit of 0.03 microg/L and a limit of quantification of 1 microg/L. Regression analysis [tandem MS method (y) and Emit assay (x)] yielded a slope of 1.09 (+/- 0.03), an intercept of 6.2 (+/- 4.5) microg/L, and S(y/x) = 27 microg/L. CONCLUSIONS: Tandem MS assay is a realistic alternative to immunoassay for the routine monitoring of CsA in transplant recipients. Its wide dynamic range has utility for pharmacokinetic studies of CsA.  相似文献   
534.
Gingrich  RD; Ginder  GD; Goeken  NE; Howe  CW; Wen  BC; Hussey  DH; Fyfe  MA 《Blood》1988,71(5):1375-1381
Forty patients with advanced hematologic malignancies or severe aplastic anemia received marrow grafts from partially mismatched, unrelated marrow donors. All patients were administered conventional prophylaxis for acute graft-v-host disease (GVHD) consisting of methotrexate and low-dose glucocorticoids. All but two patients who survived at least 30 days showed durable engraftment. Six patients survive 17+ to 36+ months following transplantation. Severe acute GVHD was seen in 47% of the patients; however, no direct correlation between GVHD and the degree of mismatching could be determined. Fatal infections were seen in 29 patients, and in the majority the infection occurred after the granulocyte count had risen to greater than 500 cells/microL. We conclude that the problems encountered in this pilot study can potentially be solved, and that further studies with this type of marrow grafting are warranted.  相似文献   
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537.
Mediastinal tuberculous lymphadenitis: CT manifestations   总被引:16,自引:0,他引:16  
Im  JG; Song  KS; Kang  HS; Park  JH; Yeon  KM; Han  MC; Kim  CW 《Radiology》1987,164(1):115-119
An analysis was done of computed tomographic (CT) scans of 23 Korean patients who had presented with a mediastinal or hilar mass on plain chest radiographs and had subsequently been found to have tuberculous lymphadenitis. Most patients were young adults. Findings of pulmonary tuberculosis were seen on plain radiographs in 14 patients. On CT, findings were of an overwhelming preponderance of involvement of the right paratracheal and tracheobronchial nodes. After injection of contrast medium, nodes larger than 2 cm in diameter invariably showed central areas of relative low density and peripheral rim enhancement. Enhanced walls were usually irregular in thickness. Some smaller nodes did not show low-density areas, but instead showed varying degrees of homogeneous enhancement. Although metastatic nodes can be of low density, experience in this study suggests that mediastinal lymphadenopathy in a young adult with the CT findings described above is characteristic enough to support a diagnosis of tuberculosis.  相似文献   
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539.
Dynamin plays an essential role in maintaining the structure and function of the glomerular filtration barrier. Specifically, dynamin regulates the actin cytoskeleton and the turnover of nephrin in podocytes, and knocking down dynamin expression causes proteinuria. Moreover, promoting dynamin oligomerization with Bis-T-23 restores podocyte function and reduces proteinuria in several animal models of chronic kidney disease. Thus, dynamin is a promising therapeutic target for treating chronic kidney disease. Here, we investigated the pathophysiological role of dynamin under proteinuric circumstances in a rat model and in humans. We found that glomerular Dnm2 and Dnm1 mRNA levels are increased prior to the onset of proteinuria in a rat model of spontaneous proteinuria. Also, in zebrafish embryos, we confirm that knocking down dynamin translation results in proteinuria. Finally, we show that the glomerular expression of dynamin and cathepsin L protein is increased in several human proteinuric kidney diseases. We propose that the increased expression of glomerular dynamin reflects an exhausted attempt to maintain and/or restore integrity of the glomerular filtration barrier. These results confirm that dynamin plays an important role in maintaining the glomerular filtration barrier, and they support the notion that dynamin is a promising therapeutic target in proteinuric kidney disease. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
540.
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