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Renal Transplantation in Patients With Pre-Transplant Donor-Specific Antibodies and Negative Flow Cytometry Crossmatches 总被引:1,自引:0,他引:1
A. M. Patel C. Pancoska S. Mulgaonkar F. L. Weng 《American journal of transplantation》2007,7(10):2371-2377
The clinical significance of pre-transplant donor-specific antibodies (DSA), despite negative cytotoxicity and flow cytometry crossmatches (FCXMs), is unknown. We performed a retrospective cohort study of 60 living donor renal transplant recipients, all with pre-transplant cytotoxicity and T-cell and B-cell FCXMs that were negative. Twenty recipients had pre-transplant DSA detected by enzyme-linked immunosorbent assays (ELISA) and/or microbead methods. Forty contemporaneous DSA-negative controls were selected. In the DSA-positive group, after a median follow-up of 8.2 months (25-75% range, 5.4-22.8 months), patient survival was 100% and allograft survival was 95.0%. Acute humoral rejection (AHR) developed in four patients (20.0%). Three of the AHR episodes occurred within the first month post-transplant. Median serum creatinine at last follow-up was 1.3 mg/dL (25-75% range, 1.0-1.6 mg/dL), versus 1.1 mg/dL (25-75% range, 0.9-1.4 mg/dL) in the DSA-negative controls (p = 0.29). Only one of the 40 controls developed AHR (2.5%). Pre-transplant DSA was associated with a significantly increased incidence of AHR (p = 0.02 by log-rank test). In conclusion, despite negative pre-transplant cytotoxicity and FCXMs, renal transplant recipients with pre-transplant DSA detected by solid-phase methods may have an increased incidence of AHR and require close monitoring post-transplant. 相似文献
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核素显像对小儿消化道出血的病因诊断 总被引:5,自引:0,他引:5
目的探讨核素显像对小儿消化道出血,特别是对Meckel憩室、肠重复畸形的病因诊断的价值。方法对26例腹痛、便血为主要症状的患儿行99m锝酸盐(99mTcO-4)显像,其中12例显像阴性者于检查后24小时有活动性出血者,再行99m锝标记红细胞显像。所有病例的诊断均经手术、病理及内窥镜等检查所证实。结果99mTcO-4显像诊断Meckel憩室和肠重复畸形的敏感性、特异性、准确性分别为85.7%(12/14)、91.7%(11/12)及88.5%(23/26)。结论核素显像具有无创、方法简单易行等特点,特别是对异位胃粘膜诊断具有较好的灵敏性和特异性。核素显像可作为下消化道出血病因诊断的有效方法。 相似文献
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通过42例重型肺心病、7例轻型肺心病、16例肺心病伴发冠心病患者和30例正常人在静息状态下的左右心脏射血分数及其临床资料的分析表明,重型肺心病患者在病情的急性发作期,存在有不同程度的左心功能不全,而轻型肺心病患者则无左心功能不全的表现。表明慢性肺心病仅在病程晚期,才由以右心为主的疾病发展成为全心病。本文还对重型肺心病与肺心病伴发冠心病患者的左心功能进行比较,结果表明,肺心病伴发冠心病患者左室功能受损程度更为明显,双重病因导致的左室功能减退,常造成心肌更严重的损害而且不容易恢复。 相似文献
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研究深低温停循环(DHCA)与逆行脑灌注(RCP)时脑组织自由基的变化。健康杂种犬14只,随机等分为DHCA组和RCP组,在停循环前(A点)、DHCA/RCP30分(B点)、DHCA/RCP60分(C点)DHCA/RCP90分(D眯)和复温再灌注30分(E点)取脑皮层lg,检测丙二醛(MDA)和超氧化物歧化酶(SOD)水平。结果见两组在A点MDA和SOD无差别。在B、C、D、E点,DHCA组MDA 相似文献
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利用特异性DNA倍增技术(polymerase chain Reaction,PCR)检测t-PA cDNA基因在表达细胞基因组中的稳定性,并对所得的PCR反应产物进行了限制性内切酶片段、分子杂交和核苷酸顺序分析等方面的研究,证实了t-PA cDNA基因已插入到表达细胞染色体中。这种方法快速、简便、灵敏度和特异性高,是检测基因工程表达细胞中cDNA基因稳定整合状况的好方法。 相似文献
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Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study. 相似文献
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Treatment of a juvenile patient with a maxillary all-ceramic resin-bonded fixed partial denture: a case report. 总被引:1,自引:0,他引:1
Dietmar Weng Stefan Ries Ernst-Jürgen Richter 《Quintessence international, dental digest》2002,33(8):584-588
Treatment of juvenile patients with a missing maxillary incisor is difficult, because an implant cannot be placed until growth is completed. The other minimally invasive alternatives are also problematic: Removable dentures are rarely accepted by juvenile patients, and the conventional resin-bonded fixed partial denture often provides a poor esthetic result because the metal retainer causes the abutment teeth to lose their natural translucency and to become grayish. Moreover, the alveolar ridge defect makes it easy to identify the prosthesis in the pontic area. The present case report describes the prosthetic treatment of a juvenile patient who had lost a maxillary incisor to trauma. To avoid the disadvantages of conventional therapies, subepithelial connective tissue was grafted to reshape the alveolar ridge. The space was closed with an all-ceramic resin-bonded fixed partial denture. 相似文献