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61.
对离体不同时间血痕进行肉眼和扫描电镜观察,获得了血痕形态结构变化的初步认识.结果随时间延长,血痕逐渐干燥、龟裂,电镜下纤维蛋白网消失,其超微结构变化观察有助于血痕经过时间的推断.  相似文献   
62.
抗—HCV阳性单采浆供血员HGV感染随访研究   总被引:3,自引:0,他引:3  
为了解单采浆供血员庚型肝炎病毒(HGV)感染及其转归,对102名抗-HCV阳性单采浆供血员冻存血清进行抗-HGV和HGVRNA检测,对抗-HGV和(或)HGVRNA阳性者作3年随访研究。采用EIA法检测抗-HGV,包被抗原来自HGV不同功能区的合成肽。应用RT-PCR法检测HGVRNA,引物选自HGVNS3区。结果表明,抗-HCV阳性单采浆供血员HGVRNA阳性率为19.61%(20/102),抗-HGV阳性率为17.65%(18/102),HGV感染率(抗HGV和/或HGVRNA阳性)为24.51%(25/102),而对照组仅为0.94%(1/106)。提示单采血浆是HGV感染的重要危险因素。HGVRNA和抗-HGV的3年阴转率分别为35.00%(7/20)和11.11%(2/18),说明HGV感染有慢性携带趋势  相似文献   
63.
This study explored the inflammatory mechanism of toxicity of hemoglobin solutions (Hb-S). Human monocytes and mouse activated peritoneal macrophages were incubated with seven different solutions. The first four consisted of non-cross-linked bovine Hb. Of these, Hb-SI was incompletely purified of stromal phospholipids, Hb-SII was contaminated with environmental bacterial endotoxins, Hb-SIII was pure hemoglobin, and Hb-SIV was pure Hb with the addition of superoxide dismutase (SOD), catalase (CAT), and mannitol (M). The other three solutions were made of pure bovine Hb cross-linked with different agents: Hb-SV, reacted with glutaraldehyde; Hb-SVI reacted with bis-3,5-dibromosalicyl fumarate (DBSF); and Hb-SVII reacted with a ring-opened dialdehyde derivative of 5'(pyro)-phosphate of adenosine (ATP) (o-ATP). The reaction of monocytes and macrophages was studied in terms of (a) O2-derived radicals, as determined by the measurement of H2O2 and lipid peroxides; (b) complement factor C3a desArg; (c) 6-keto-prostaglandin F1 alpha (stable metabolite of prostacyclin); and (d) TxB2 (stable metabolite of thromboxane) released into the culture supernatants. The most significant reactions were obtained with the solutions contaminated with stromal phospholipids or bacterial endotoxins. Pure Hb was less reactive. Further reduction in proinflammatory activity was achieved by the addition of oxygen radical-scavengers (SOD, CAT, and M), or by the cross-linking of Hb with DBSF or o-ATP.  相似文献   
64.
Using a plasma separator, it is possible to wash large volumes of whole blood free of plasma proteins in short periods. The novelty, however, is that the same apparatus can be used to reversibly hemolyze and reseal the red blood cells (RBCs) using hypotonic and hypertonic dialysates, respectively. This technique was assessed using the fluorescent exogenous agent uranin (fluorescein sodium). Results indicate that the encapsulation of the RBCs can be completed in under 2 h. The encapsulation efficiency of the RBCs was approximately 80% with a RBC recovery rate of 75%.  相似文献   
65.
Accurate assessment and replacement of blood loss and fluid–electrolyte deficit during craniosynostosis repair is difficult owing to patient size and the diversity of surgical technique. Forty-three patients undergoing primary craniosynostosis repair over a 10-year period were studied retrospectively to determine blood loss and fluid deficit and to assess blood transfusion practices during both intraoperative and postoperative periods. Blood loss was calculated on the basis of estimated red cell mass (ERCM) and fluid-electrolyte imbalance was investigated with blood samplings. Blood transfusion was considered appropriate if the postoperative or posttransfusion ERCM was within 12% of the preoperative value. Estimated fluid requirement (EFR) was used in 4 ml kg–1 h–1 except for neonates. Intraoperatively, 80% of all patients were appropriately managed with respect to blood transfusion and EFR. Postoperatively only 20% of the patients receiving transfusions were transfused appropriately. In 23.3% of these patients (10/43) unexpected respiratory distress developed immediately after their recovery from the anesthesia. With the measurement of estimated blood volume and allowable blood loss, appropriate transfusion could be achieved for the successful treatment of the primary craniosynostosis. Received: 16 February 1998  相似文献   
66.
程光存  严中亚 《中华实验外科杂志》2004,21(9):1091-1092,i003
目的 比较静态和动态旋转系统中构建组织工程化血管模型中血管内皮细胞分泌功能。方法新型可降解材料聚羟基丁酸酯(PHB),用胶原包埋,形成多孔状PHB 胶原管形支架。分离传代、分化人脐静脉内皮细胞,接种于PHB管型支架内腔面,分别在静态、动态旋转系统中培养14 d后,测定血管内皮细胞分泌一氧化氮(NO)、前列环素(PGI2)水平。结果 在动态旋转系统构建组织工程化血管模型中血管内皮细胞分泌NO、PGI2水平显著高于静态系统,在11 d NO分别为(120.52±3.83)μmmol/L、(80.98±5.98)μmmol/L,PGI2分另9为(20.48±1.52)μg/L,(16.59±1.29)μg/L,与静态系统相比,差异有显著性(P<0.05)。结论胶原包埋PHB支架有利于细胞的黏附和生长,可作为组织工程化血管的支架材料。在动态旋转系统构建组织工程化血管模型中血管内皮细胞,具有与正常血管类似的"生理功能"。  相似文献   
67.
目的 研究胃癌根治术病人围手术期异体输血外周血单核细胞(PBMCs)白细胞分化抗原40配体(CD40L)表达的变化。方法 胃癌根治术病人30例,随机分为3组,每组10例。A组围术期不输血,B组围术期输入去白细胞的全血,C组围术期输入异体全血。另选10例健康人作为对照。分别在手术前、术后2、5、10 d采外周静脉血5 ml,用Ficoll分离液梯度离心法分离出PBMCs和血浆,将PBMCs置于自身血浆环境中,并在植物血凝素(PHA,20 mg/L)的刺激下进行培养,48 h后收获细胞,用流式细胞术检测CD40L表达。结果 健康人外周血未受PHA刺激时检测不到CD40L的表达,经PHA刺激后CD40L 细胞占CD4 T细胞的百分数为1.7%±0.4%,与三组胃癌病人术前比较差异无显著性(P>0.05)。与术前比较,B组术后2 d PBMCs CD40L表达升高(P<0.05),C组术后各时点升高(P<0.05);与A组比较,B组术后2 d升高(P<0.05),C组术后各时点升高(P<0.05);与B组比较,C组术后各时点升高(P<0.05)。结论 围手术期异体输血可造成免疫抑制,输异体血后CD40L表达增加,且输全血比输去白细胞的全血更明显。围手术期成分输血优于输注全血。  相似文献   
68.
OBJECTIVE: To accurately measure blood loss during childbirth in a developing country. METHOD: The alkaline hematin technique was used to quantify blood lost during delivery and 24 h postpartum in 158 women in Pemba Island, Zanzibar. RESULT: Women were found to lose less blood during childbirth and 24 h postpartum than previously reported. Compared with laboratory values, nurse-midwives approximated blood loss accurately (mean difference, i.e., mean underestimation by nurse-midwives, 4.90 mL); however, their imprecision was greater for higher laboratory values. CONCLUSION: This study may prompt further investigation, as no comparable data exist for developing countries where maternal mortality is high and severe anemia prevalent.  相似文献   
69.
ABO血型不合的异基因造血干细胞移植--2例报告附文献复习   总被引:2,自引:1,他引:1  
探讨ABO血型不合的异基因造血干细胞移植 (Allo -HSCT)的造血问题。方法 :对 2例患者分别进行异基因外周血造血干细胞移植 (Allo -PBSCT)及脐血造血干细胞移植 (CBSCT) ,用血细胞分离机或 6 %羟乙基淀粉去除移植物中的红细胞 ,定期检测受者血型 ,根据情况输注血细胞。结果 :2例患者全部获得造血重建 ,未出现溶血反应。结论 :ABO血型不合可以进行Allo -HSCT ,去除供者移植物中的红细胞能有效地防止急性溶血反应的发生 ,定期检测受者血型 ,及时调整输血方案有重要的临床意义。  相似文献   
70.
Summary Postnatal formation of the Blood-Testis Barrier (BTB) in the rat was studied by either fixation in hypertonic fixative or employing lanthanum tracer. After 15 days of age, meiosis has reached different stages of spermatogenesis in differnt zones of the seminiferous cords. Only in those parts where germ cells are in the pachytene stage of meiosis do Sertoli cells form an effective barrier or tight compartment. Between 16 and 19 days of age, final formation of the BTB, which is to be found in the adult rat testis, occurs by zygotene and then leptotene stages successively entering the tight compartment. Thus, formation of a BTB by Sertoli cells does not occur synchronously along the length of the seminiferous cord but in accordance with the stage of meiosis of the associated germ cells.  相似文献   
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