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排序方式: 共有2376条查询结果,搜索用时 15 毫秒
1.
Hidetaro Mori Keisuke Hiraoka Ryoichi Yorifuji Tohru Iwasaki Syuzo Gomikawa Ohshi Inagaki Seishi Inoue Yoshihiro Takamitsu Yoshikazu Fujita 《Artificial organs》1994,18(10):725-728
Abstract: The adsorptive characteristics of 5 dialysis membranes for recombinant human erythropoietin (EPO) were studied in vitro in a closed circuit system. For 120 min, EPO added with bovine serum was significantly adsorbed by polymethylmetacrylate (PMMA) and polyacry–lonitrile (PAN) membranes but not by Cuprophan, ethylene vinyl alcohol (EVAL), or polysulfone (PS) membranes. In addition the EPO adsorptive rate, as well as that of β2 –microglobulin (β2 –MG), was greater with a PMMA membrane than with a PAN membrane. EPO was not detected in the ultrafiltrate at 15 min with 5 membranes. These results indicate that EPO was eliminated by membrane adsorption only with some dialysis membranes. 相似文献
2.
Erythropoietin production in healthy volunteers subjected to controlled hypobaric hypoxia: further evidence against a role for adenosine 总被引:2,自引:2,他引:0
Aims Objective of this study was to investigate whether adenosine modulates renal erythropoietin production.
Methods In the present study erythropoietin production was stimulated by hypobaric hypoxia by subjecting healthy volunteers to a simulated altitude of 4000 m in a low pressure chamber for 5.5 h. During exposure to hypoxia the subjects received i.v. in a randomized, single-blind, cross-over fashion the non-specific adenosine antagonist theophylline, the adenosine reuptake inhibitor dipyridamole and placebo.
Results Contrary to the working hypothesis, theophylline did not decrease and dipyridamole did not further boost erythropoietin concentrations.
Conclusions The results are in agreement with our earlier study using haemorrhage as a controlled physiological stimulus of erythropoietin production, and would question a major role for adenosine as a mediator of renal erythropoietin production. 相似文献
Methods In the present study erythropoietin production was stimulated by hypobaric hypoxia by subjecting healthy volunteers to a simulated altitude of 4000 m in a low pressure chamber for 5.5 h. During exposure to hypoxia the subjects received i.v. in a randomized, single-blind, cross-over fashion the non-specific adenosine antagonist theophylline, the adenosine reuptake inhibitor dipyridamole and placebo.
Results Contrary to the working hypothesis, theophylline did not decrease and dipyridamole did not further boost erythropoietin concentrations.
Conclusions The results are in agreement with our earlier study using haemorrhage as a controlled physiological stimulus of erythropoietin production, and would question a major role for adenosine as a mediator of renal erythropoietin production. 相似文献
3.
4.
Erythropoietin deficiency and relative resistance cause anaemia in post-renal transplant recipients with normal renal function 总被引:6,自引:2,他引:4
Nampoory M. R. N.; Johny K. V.; Al-Hilali N.; Seshadri M. S.; Kanagasabhapathy A. S. 《Nephrology, dialysis, transplantation》1996,11(1):177-181
BACKGROUND: Following successful renal transplantation, blood erythropoietin(Epo) levels peak in two phases during the first 23 months,and blood haemoglobin/haematocrit (Hb/Hct) levels are restoredto normal in a period of 26 months. However, some transplantrecipients continue to remain anaemic in spite of normal graftfunction and in the absence of recognizable causes. The roleof endogenous Epo production in the causation of anaemia insuch patients is poorly understood and has been investigatedin this study. METHODS: Twenty-three post-renal transplant recipients with stable normalrenal function were studied. Eleven of these patients had normalHb/Hct levels (group 1) and served as control for the rest 12patients with anaemia (group 2). Patients included in group2 had no readily recognizable cause for their anaemia. Otherlaboratory and clinical findings were similar in both groups.Patients with erythrocytosis were excluded. Serum Epo levelswere measured in all patients. Five patients in group 2 weretreated with recombinant human erythropoietin (rHuEpo) and theirerythropoietic response was assessed. rHuEpo was discontinuedwhen the target Hb/Hct levels (lowest normal range) were achievedand the patients were followed up for a further period of 912months. RESULTS: Five patients in group 1 had normal expected serum Epo levelswhereas the other six patients had inappropriately high serumEpo levels with respect to their Hb/Hct status suggestive ofrelative Epo resistance. Serum Epo levels in allpatients except two in group 2 were low indicative of Epodeficiency. The two exceptional patients in group 2 hadhigher serum Epo levels in the presence of anaemia suggestiveof relative Epo resistance. All five patients treated with rHuEpo responded adequately byachieving normal Hb/Hct levels. Three of them were originallyEpo deficient and they reached target Hb/Hct levelsin a mean period of 4 weeks, requiring a mean cumulative rHuEpodose of 428.3 units/kg. The other two patients with higher initialserum Epo levels, and considered to be Epo resistant,required an average of 11 weeks of treatment and a mean cumulativerHuEpo dose of 1582.5 units/ kg, indicating an increased Epodemand. On cessation of therapy the Hb/Hct levels fell in allfive patients to pretreatment values in 6 months. CONCLUSIONS: There are important variations in the endogenous Epo productionin renal transplant patients with normal renal function, thecause of which is not clear. Epo deficiency and relative Eporesistance play a causative role for anaemia in some post-renaltransplant recipients with stable normal renal function. Theyrespond adequately to rHuEpo administration. 相似文献
5.
Treatment of dyskeratosis congenita with Granulocyte Colony-Stimulating Factor and Erythropoietin 总被引:1,自引:0,他引:1
Blanche P. Alter Frank H. Gardner & Robert E. Hall 《British journal of haematology》1997,97(2):309-311
Aplastic anaemia is both frequent and difficult to manage in patients with dyskeratosis congenita (DC). We recently treated a 23-year-old male for a year with granulocyte colony-stimulating factor (G-CSF) and erythropoietin (Ep), with an excellent neutrophil response, and a transient effect on haemoglobin levels. G-CSF alone or combined with other cytokines may provide at least a partial effect in pancytopenic patients with DC. 相似文献
6.
KARL-ANTON KREUZER JU¨RGEN KURT ROCKSTROH WOLFGANG JELKMANN ALBERT THEISEN ULRICH SPENGLER & TILMANN SAUERBRUCH 《British journal of haematology》1997,96(2):235-239
Severe anaemia is a frequent complication in advanced HIV infection. In our study we investigated the interaction between cytokine network, HIV infection and erythropoietin (Epo) response with increasing anaemia levels. No correlations could be established between circulating tumour necrosis factor (TNF)-alpha and any of the examined parameters. However, a negative correlation was found between haemoglobin values and soluble TNF receptor levels (sTNF-R-I: r = −0.54; P < 0.001; sTNF-R II: r = −0.47; P < 0.001) as well as interleukin-6 levels ( r = −0.29; P < 0.001). In contrast, no significant increase in log[Epo], counterbalancing haemoglobin decline and paralleling the rise in sTNF receptors, was found. In patients classified as stage III, according to the Centers for Disease Control (CDC) classification, the erythropoietin response was significantly more impaired than in patients from CDC groups I and II ( P < 0.001). The results of this study suggest that similar to its action in vitro , activation of the TNF/TNF-R system may impair erythropoietin production in HIV-associated anaemia. Due to the brief half-life of TNF-α, this activation is particularly reflected by elevations of soluble TNF receptor levels. 相似文献
7.
用小鼠胎肝细胞体外血浆凝块培养红系集落(Erythroid colong formig unit inculturc,E-CFUc)方法,以红细胞生成素(Erythropoietin,EPO)850323为标准试剂,测定正常人、贫血病人血清EPO浓度。实验用妊娠13~15d小鼠胎肝细胞。血清均经透析处理,培养液中加量最大不超过10%。EPO(850323)在培养液中浓度为2.5~100mU/ml。血清EPO(mU/ml)测定结果:28例正常人为48.O±17.7,12例再生障碍性贫血病人为946~>10000,1例巨幼细胞性贫血病人为500,1例缺铁性贫血病人为400和18例慢性肾功能衰竭病人则为94.2±87.6。结果表明:贫血病因对血清EPO浓度有影响。 相似文献
8.
P. Andersson K. LeBlanc B-. Eriksson J. Samuelsson 《European journal of haematology》1997,59(5):310-317
Abstract: Polycythaemia vera (PV) is a myeloproliferative disorder characterized by haematopoietic progenitor cells being hypersensitive to cytokines such as erythropoietin, interleukin-3, stem cell factor and insulin-like growth factor 1, which results in an increased production of mature blood cells. The pathogenetic cellular mechanism(s) behind this hypersensitivity to cytokines is unknown, but the number of cytokine receptors and the interaction between ligand and receptor are normal in PV. Interest has therefore focused on post-receptor mechanism(s). Haematopoietic cell phosphatase (HCP) is an intracellular tyrosine phosphatase that has been demonstrated to regulate proliferative signals negatively induced by the cytokines mentioned above. Moreover, motheaten mice that genetically lack HCP have an increased amount of erythroid progenitors that are hypersensitive to Epo, and patients with familial polycythaemia have been shown to exhibit a mutation of the Epo receptor gene that includes the docking site for HCP. We therefore studied mRNA expression of HCP in pure populations of CD34+ cells, granulocytes, platelets and lymphocytes from patients with PV, chronic myeloid leukaemia (CML) or essential thrombocythemia (ET), as well as healthy controls. Using a polymerase chain reaction analysis employing specific primers for HCP, we failed to detect any abnormalities of HCP expression in PV in any of the cell populations that were examined. Moreover, HCP mRNA expression was similar in ET and CML compared to controls. Finally, Western blot analysis revealed a normal HCP protein content in PV granulocytes and platelets. We therefore conclude that neither an impaired expression of the HCP gene nor a defect in HCP protein synthesis is present in PV, and does not seem to play a role in the aetiology of this disorder. 相似文献
9.
Eugenio Baraldi Giovanni Montini Stefania Zanconato Graziella Zacchello Franco Zacchello 《Pediatric nephrology (Berlin, Germany)》1990,4(6):623-626
The aim of this study was to evaluate the effect of correction of chronic anaemia on the physical performance and the cardiovascular response to effort in children with end-stage renal disease (ESRD) maintained by haemodialysis. Seven patients (mean age 13.9 years) underwent triangular-type treadmill exercise testing before [haemoglobin (Hb) 6.3±0.9 g/dl] and after (Hb 11.2±1.2 g/dl) anaemia correction with recombinant human erythropoietin (rHuEPO). After treatment, the work-load reached, the peak oxygen uptake and average ventilatory anaerobic threshold (VAT) values were significantly increased (P<0.01,P<0.001,P<0.05 respectively). VAT values, expressed as a percentage of normal values, increased from 55.7±16.6% to 82.4±21%. This improvement correlated well with the increase in Hb (r=0.79). Oxygen pulse also increased significantly, when tested after anacmia correction. In conclusion, these data demonstrate that when the anaemia of children with ESRD is corrected with rHuEPO, there is a clear improvement in acrobic work capacity and effort tolerance. 相似文献
10.
重组人红细胞生成素治疗肾性贫血的临床分析 总被引:1,自引:0,他引:1
目的 观察重组人红细胞生成素 (RhEPO)对肾性贫血的治疗作用。方法 根据使用EPO剂量的不同将 39例慢性肾衰竭并血液透析病人分成 4组 ,观察治疗后 2、4、12个月时与治疗前 (0月 )相比红细胞数 (RBC)、红细胞比积 (Hct)及血红蛋白含量 (Hb)的变化。结果 2 4例使用EPO10 0 - 15 0IU/ (kg·w) (6 0 0 0IU/w - 90 0 0IU/w) ,治疗后RBC、Hct、Hb较治疗前有显著升高 (P≤ 0 .0 0 1) ;5例使用EPO5 0IU/ (kg·w) (30 0 0IU/w) +间断输血患者 ,其RBC、Hct、Hb升高不显著 ;10例不用EPO而单纯输血患者 ,其RBC、Hct、Hb无明显变化 (P >0 .0 5 )。结论 EPO能较好地纠正肾性贫血 ;单纯输血不能治疗肾性贫血 相似文献