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81.
Longitudinal studies were conducted over a five-year period for HLA antibodies on 493 sera tested from 54 kidney transplant patients. HLA single antigen beads were employed to establish donor specificity of the antibodies. Only 3 of 22 patients without antibodies rejected a graft in contrast to 17 out of 32 patients with posttransplant antibodies (p = 0.003). Using a serum creatinine value of 4.0 mg/dL as the cut-off for a failed graft, 4 of 22 patients without antibodies failed compared to 21 of 32 with antibodies (p = 0.0006). Among patients with donor-specific antibodies (DSA) 13 of 15 failed (p = 0.000004). Even among patients with non-donor specific antibodies (NDSA), 8 of 17 failed (p = 0.05). Among patients who could be identified as making de novo antibodies (since they developed antibodies while not having antibodies for more than six months after transplantation), 6 of 11 failed (p = 0.03). Sequential testing for HLA antibodies shows that antibodies appear prior to a rise in serum creatinine and subsequent graft failure. The very strong association between the production of HLA antibodies after transplantation and graft failure indicates the importance of monitoring for posttransplant HLA antibodies.  相似文献   
82.
83.
DataBankandConsultingSystemforMedicalManagementofPatienswithAcuteRadiationSickness¥TangZhongming;YeGenyao;MaoBingzhi;LuoQingl...  相似文献   
84.
脊髓血管畸形的临床发病率较低,仅为颅内血管畸形或脊髓新生物的1/10左右.本病可能与其它组织的血管异常同时存在,如皮肤血管痣(Cobb综合征),皮肤、粘膜病变,和Klipple-Trenaunay-Weber综合征等.本文报告的与胸腔血管畸形同时存在的脊髓血管畸形,我们尚未见诸报道.本文还结合文献就脊髓血管畸形导致脊髓功能损害的病理生理作了阐述.  相似文献   
85.
86.
BACKGROUND: Equilibration of hemoglobin concentration after transfusion has been estimated to take about 24 hours, but some studies have shown that earlier measurements reflect steady-state values in persons who have not bled recently. This study was aimed at assessing the changes over time in hemoglobin concentration after transfusion in acutely anemic patients because of recent bleeding. STUDY DESIGN AND METHODS: Thirty-two normovolemic patients recovering from an acute bleeding episode who were no longer thought to be bleeding and who received a 2- unit red cell transfusion were studied. At baseline and 15, 30, 60, and 120 minutes and 24 hours after transfusion, hemoglobin concentration and hematocrit values were measured. RESULTS: The administration of 2 units of packed red cells elicited a 24-hour increase of 22.4 +/− 6.8 g per L in hemoglobin concentration. Hemoglobin values were not different at any of the defined posttransfusion times. Hematocrit levels experienced similar changes over time. Agreement between 15-minute and 24-hour values was excellent, as only 6 percent of patients exhibited a clinically significant difference (> 6 g/L) between the hemoglobin measurements. CONCLUSION: Hemoglobin and hematocrit values rapidly equilibrate after transfusion in normovolemic patients who are recovering from an acute bleeding episode. This fact would allow a rapid assessment of the effects of transfusion and of the recurrence of bleeding in patients remaining at risk.  相似文献   
87.
采用同种脂肪提取液复制犬呼吸窘迫综合征模型,观察前列腺素E_1(PGE_1)对其治疗作用。结果表明,PGE_1可改善该模型的低氧血症,降低肺毛细血管通透性,减轻肺水肿,其减轻肺损伤的机理与其抑制多形核白细胞粘附、氧自由基产生及保护Ⅱ-型肺泡上皮细胞等有关。  相似文献   
88.
作者对膝关节痛和休息痛病人21例做了股、胫骨内压和关节镜检查,其均值股骨髁0.143±0.01kPa,16例(76.19%)超过对照组0.130kPa(P<0.01);胫骨髁0.180±0.022kPa,18例(85.7%),超过对照组0.105kPa。同时测量膝关节腔内压21例。均值为0.135±0.035kPa,18例(85.7%)高于对照组0.120kPa。认为骨内压增高是引起膝关节痛的原因。本文还就膝关节特发性骨内高压症的临床表现、镜下特点、个体临界骨内压和治疗方法进行了探讨。  相似文献   
89.
毛慧生  宁连胜 《中国肿瘤临床》1992,19(3):174-179,240
应用激光多普勒血流仪测量比较津白Ⅱ号小鼠三个部位皮肤的血流,观察HDZ对血流的影响,评价了HDZ的体内热增敏作用。结果发现,同一小鼠不同部位的血流是不同的,同一部位的连续6天结果无何区别。但同部位小鼠间的血流差别可达1倍以上。提示了预测放、化、热疗的疗效时,监测个体血流的前后变化有重要意义。2.5mg/kg以上的HDZ可以明显降低血流75%左右。HDZ与高温联合应用时对肿瘤显示了热增敏效应。  相似文献   
90.
BACKGROUND: Cyclosporin has been shown to facilitate renal vasoconstriction and to have an antinatriuretic effect. The existence of an interference of cyclosporin with the vasodilating properties of endothelium mediated by nitric oxide production could mediate these effects. On the other hand, the infusion of the nitric oxide precursor L-arginine has been shown to induce renal vasodilatation and to facilitate natriuresis in normal volunteers. We have investigated the renal effects of the administration of an infusion of L-arginine in renal transplant patients chronically treated with cyclosporin. To facilitate the analysis of the data the effects of the administration of a similar dose of cyclosporin on renal function during the infusion of a vehicle were also investigated during the administration of a vehicle of L-arginine. DESIGN: Ten male renal transplant patients, chronically treated with cyclosporin and with a stable renal function were studied during 2 consecutive days after the administration of the usual morning dose of cyclosporin. The first day they received an intravenous infusion of vehicle and the second the infusion of graded doses of L-arginine (50, 100, 150 mg/kg/h) during 3 consecutive h. RESULTS: The first day, after cyclosporin administration a significant fall (P < 0.01) was observed in natriuresis and kaliuresis in the absence of changes in renal plasma flow and glomerular filtration rate. After the administration of L-arginine significant (P < 0.01) increases of renal plasma flow, glomerular filtration rate, and natriuresis were seen. The increase in blood levels of cyclosporin after its administration did not differ between days 1 and 2. CONCLUSION: These results indicate that L-arginine facilitates renal vasodilatation and natriuresis in renal transplant patients. Furthermore, the observed increase in sodium excretion could indicate that L-arginine counteracts the antinatriuretic effect of cyclosporin.   相似文献   
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