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目的:已有实验研究证明,移植骨髓来源内皮祖细胞可以促进球囊损伤后血管内皮的修复及抑制内膜的增生.那么移植骨髓来源内皮祖细胞对自体静脉移植术后静脉血管内皮修复和内膜增生是否起同样的作用?观察自体骨髓来源内皮祖细胞移植对自体静脉移植术后静脉桥血管再内皮化及内膜增生的作用。方法:实验于2007-01/08在北华大学附属医院内科实验室完成。实验室级别:P2级。①实验材料:6~8月龄雄性新西兰大白兔由解放军第二军医大学实验动物中心提供.体质量(2.5±0.5)kg,清洁级,实验过程中对动物处置符合动物伦理学标准。②实验方法:抽取成年兔骨髓分离制备骨髓单个核细胞,体外扩增法培养出骨髓来源内皮祖细胞.在培养第7天通过Ac-Dil-LDL、FITC-BS-1双染色及流式细胞仪检测CD34、CD133、FIK-1表达进行细胞鉴定,应用DAPI荧光染料体外标记培养7 d的骨髓来源内皮祖细胞、将成年新西兰大白兔23只随机分为细胞移植组(n=13)和对照组(n=10)进行自体左颈外静脉、颈总动脉移植术,在建模后第3天将DAPI标记的骨髓来源内皮祖细胞悬液经耳缘静脉植入细胞移植组动物体内,埘照组植入等量的PBS液③实验评估:细胞移植后4周.观察兔静脉移植段血管性及内膜厚度。结果:23只免均进入结果分析,无脱落:①通过体外扩增法培养的骨髓来源内皮组细胞,培养至7 d可见AC-Dil-LDI及FITC-BS-1双染色阳性细胞并表达CD34、CD133及FIK-1。②在呈绿荧光染色的血管内皮中可见有部分不均匀的散发蓝色荧光(DAPI标记细胞的细胞核)。③细胞移植组兔静脉血管内皮有DAPI标记的细胞.且内膜厚度明显低于对照组(P<0.05)结论:自体骨髓来源的内皮祖细胞移植可以促进损伤部位血管内皮的修复.并抑制内膜的过度增生。  相似文献   
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ABSTRACT: BACKGROUND: Several World Health Organization (WHO) initiatives aim to improve the accessibility of safe and effective medicines for children. A first step in achieving this goal is to obtain a baseline measure of access to essential medicines. The objective of this project was to measure the availability, prices, and affordability of children's medicines in Guatemala. METHODS: An adaption of the standardized methodology developed by the World Health Organization and Health Action International (HAI) was used to conduct a cross sectional survey to collect data on availability and final patient prices of medicines in public and private sector medicine outlets during April and May of 2010. RESULTS: A subset of the public sector, Programa de Accesibilidad a los Medicamentos (PROAM), had the lowest average availability (25%) compared to the private sector (35%). In the private sector, highest and lowest priced medicines were 22.7 and 10.7 times more expensive than their international reference price comparison. Treatments were generally unaffordable, costing as much as 15 days wages for a course of ceftriaxone. CONCLUSIONS: Analysis of the procurement, supply and distribution of specific medicines is needed to determine reasons for lack of availability. Improvements to accessibility could be made by developing an essential medicines list for children and including these medicines in national purchasing lists.  相似文献   
64.
Primary plasma cell leukemia (PPCL) is a rare form of disease accounting for 1-2 percent of myelomas. Between September 1990 and November 2000, among 540 patients with myeloma studied, 24 fulfilled the criteria of PPCL (4.4 percent). We found high frequencies of female patients (62 percent), Bence Jones proteinuria (79 percent), anemia (88 percent), bleeding (54 percent), confusional syndrome (42 percent), weight loss (71 percent), hepatomegaly (25 percent), splenomegaly (21 percent), leukocytosis (62 percent), and thrombocytopenia (71 percent). High serum levels of creatinine, calcium, lactate dehydrogenase (LDH), and beta(2)-microglobulin were detected in 50 percent, 37 percent, 58 percent, and 71 percent, respectively. Four patients were treated with vincristine, melphalan, cyclophosphamide, prednisone, and adriamycin (VMCPA), 12 with vincristine, adriamycin, and dexamethasone (VAD), and 8 with M-80 (oral melphalan 80 mg/m(2) plus dexamethasone 40 mg/m(2)). There was a trend toward lower values of Karnofsky score (P=0.07) and higher values of LDH (P=0.2) in the VAD group. Other clinical characteristics were comparable among the three groups. Complete plus partial responses were achieved in one and six patients treated with VMCPA and M-80, respectively. All patients treated with VAD failed to respond to treatment. Patients receiving the M-80 regimen experienced higher platelet toxicity (P=0.05), vomiting (P<0.0003), and mucositis. Also, the need for red blood cell transfusions was higher in the M-80 group. Median overall survival was 60 days. Overall survival was better in patients achieving complete or partial response. In conclusion, our study illustrates that intermediate doses of melphalan plus dexamethasone are an effective chemotherapy regimen for this aggressive disease. Response to treatment is the only prognostic factor for survival in these patients.  相似文献   
65.
Platelet-derived growth factor promotes polymorphonuclear leukocyte activation   总被引:13,自引:0,他引:13  
Tzeng  DY; Deuel  TF; Huang  JS; Senior  RM; Boxer  LA; Baehner  RL 《Blood》1984,64(5):1123-1128
The platelet-derived growth factor (PDGF) has several well defined important biologic activities. Platelet-derived growth factor is the major mitogen in human serum for cells of mesenchymal origins; it is a potent chemoattractant protein for human monocytes, neutrophils, fibroblasts, and smooth muscle cells; and has been implicated in transformation by simian sarcoma virus and perhaps in transformation by other agents as well. In this article, PDGF has been shown to stimulate activation of human peripheral blood neutrophils defined by loss of membrane associated calcium as reflected by loss of chlortetracycline fluorescence, release of superoxide anion and specific granule enzymes, and enhanced neutrophil adherence and aggregation. These responses occurred in a dose-dependent fashion at concentrations of PDGF between 10 ng/mL (0.4 nmol/L) and 40 ng/mL (1.5 nmol/L) and were comparable to effects obtained with optimal concentrations of fMLP and C5a. Degranulation induced by PDGF was selective for secondary (specific) granules and not primary (azurophil) granules. Platelet-derived growth factor thus is ideally suited for a pivotal role in attracting inflammatory cells locally and initiating neutrophil activation at sites of blood vessel injury. Platelet-derived growth factor or a closely related protein also may play an important role in attracting and activating neutrophils in association with inflammatory tumors.  相似文献   
66.
Studies using an adapted immunofluorescence technique (IFT) on Crithidia luciliae to determine the complement fixing ability of antibodies to dsDNA in relation to disease manifestations, i.e., nephritis, have yielded conflicting results. To establish the relevance of these determinations, we studied sera containing antibodies to dsDNA from 64 patients with systemic lupus erythematosus (SLE), and found that anti-dsDNA of 52% of these sera had the ability to fix complement. SLE patients with nephritis demonstrated a much higher incidence of complement fixing anti-dsDNA (83%) than patients without nephritis (17%, p less than 0.01). On the other hand, patients with nephritis also had higher titers of anti-dsDNA (mean 1:400) than patients without nephritis (mean titer 1:75; p less than 0.01). A clearcut correlation between anti-dsDNA titer and complement fixing anti-dsDNA titer (p less than 0.01) was observed which obviously disturbs the correlation between nephritis and complement fixing anti-dsDNA. Comparing matched sera from patients with nephritis and patients without nephritis with the same antidsDNA titer, we found no difference in complement fixing anti-dsDNA. In the IFT used to measure complement fixing anti-dsDNA, incubation of the Crithidia slides with patients' serum was followed by an incubation with fresh normal serum which served as a source of complement. We observed that this incubation with fresh normal serum resulted in elution of anti-dsDNA antibodies from kinetoplast DNA. This elution was caused by IgG present in normal serum.  相似文献   
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高效液相色谱法测定尿中美芬妥英及代谢产物4'-羟基美芬妥英阮邹荣,程源深,丁德云(浙江医科大学附属第二医院临床药理研究所310009)美芬妥英(mephenytoin,MP)化学名为3-甲基-5-苯基-5-乙基乙内酰脲(3-methyl-5-phen...  相似文献   
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