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471.
目的:研究表明,结蛋白和波形蛋白可反映肌肉损伤再生的情况,同时结蛋白可反应肌力的大小。比较特发性和先天性脊柱侧凸患者顶椎处凹凸两侧椎旁肌形态和结蛋白及波行蛋白的表达,探讨椎旁肌在特发性脊柱侧凸发生发展中的作用。方法:①选择2005-07/2006-11间南方医科大学南方医院脊柱骨病科收治的部分特发性脊柱侧凸患者12例,Cobb角平均73.8°;先天性脊柱侧凸患者5例,Cobb角平均36.0°;腰椎间盘突出症患者2例和胸腰椎管内占位性病变患者3例作为正常对照。所有患者年龄均在10~20岁。②对脊柱侧凸患者顶椎凹凸两侧及正常对照组患者椎旁肌进行活检,术前均签署知情同意书。③采用光镜和电镜下观察椎旁肌的形态改变;SP法分别对光镜切片的结蛋白和波行蛋白进行免疫组织化学染色,在光镜下观察蛋白表达;应用图像分析系统测量结蛋白免疫组织化学染色后反应椎旁肌蛋白表达强弱的吸光度(A)。结果:22例患者全部进入结果分析。①椎旁肌组织形态:特发性脊柱侧凸患者椎旁肌在光镜及电镜下均有病变,凹侧椎旁肌病变较重,凸侧椎旁肌相对正常。②结蛋白免疫组织化学的阳性表达:结蛋白在各组椎旁肌中均有不同程度的表达,组间比较差别显著(P<0.01)。特发性脊柱侧凸及先天性脊柱侧凸患者椎旁肌在顶椎凸侧比正常组结蛋白表达稍强(0.2727±0.0478,0.2768±0.0372,0.2429±0.0272,P<0.05),特发性脊柱侧凸及先天性脊柱侧凸患者椎旁肌在顶椎凹侧相对于正常组表达减弱(0.1898±0.0258,0.1869±0.0306,0.2429±0.0272,P<0.05)。③波行蛋白免疫组织化学的阳性表达:各组间椎旁肌肌纤维内均无波形蛋白表达。特发性脊柱侧凸与先天性脊柱侧凸患者同侧椎旁肌两组间在形态和结蛋白及波行蛋白表达无明显差别(P>0.05)。结论:特发性脊柱侧凸患者椎旁肌内波形蛋白表达均为阴性,提示椎旁肌不存在再生现象。与先天性脊柱侧凸类似,特发性脊柱侧凸患者椎旁肌结蛋白表达凸侧增强及凹侧减弱为继发性改变。 相似文献
472.
2,4,6-三硝基苯磺酸诱导小鼠炎症性肠病模型的建立 总被引:1,自引:0,他引:1
目的:建立2,4,6-三硝基苯磺酸诱导的结肠炎动物模型,并分析其剂量效应。方法:实验于2006-05/09在南方医院消化内科研究所完成,选用SPF级雌性Balb/c小鼠50只,按随机数字表法分为5组,每组10只,对照组予以300g/L乙醇溶液灌肠1次;其他4组分别给予含25mg/kg,50mg/kg,100mg/kg,150mg/kg2,4,6-三硝基苯磺酸的300g/L乙醇溶液灌肠1次。各组于造模后3,7,21,28d各处死1只小鼠,观察结肠的大体形态。造模后21d观察各组小鼠结肠的病理组织切片,并检测中性粒细胞的髓过氧化物酶活性。结果:造模过程中50,100,150mg/kg2,4,6-三硝基苯磺酸组各死亡2,3,3只小鼠。①各组小鼠造模后的一般情况:对照组及25mg/kg2,4,6-三硝基苯磺酸组小鼠发生一过性的结肠机械损伤表现,出现便血等现象,但3~7d后开始缓解;而50~150mg/kg2,4,6-三硝基苯磺酸组小鼠出现便血,腹泻。②各组小鼠结肠的大体形态及病理组织学观察结果:对照组和25mg/kg2,4,6-三硝基苯磺酸组小鼠肠道在第7天时表现为无粘连,局部充血,肠壁不增厚,未见溃疡,于第3周时局部充血已好转;结肠病理切片大致正常。50~150mg/kg2,4,6-三硝基苯磺酸组小鼠肠道肉眼可见粘连,肠腔增大,充血水肿,溃疡形成,出现肠道增厚,病理切片见黏膜下层水肿,固有层炎症细胞浸润等现象,以上现象于造模4周后开始缓解。其中当2,4,6-三硝基苯磺酸剂量为100mg/kg时作用达到高峰。③各组小鼠的中性粒细胞髓过氧化物酶活性比较:50,100,150mg/kg2,4,6-三硝基苯磺酸组均显著高于对照组[(14.17±3.33,18.50±2.33,18.17±1.50,4.83±2.00)nkat/L,(P<0.01)]。结论:应用含100mg/kg2,4,6-三硝基苯磺酸的300g/L乙醇溶液灌肠是诱导小鼠结肠炎较为理想的方法。 相似文献
473.
BACKGROUND: During storage of platelet concentrates at 22 degrees C, changes occur in surface glycoproteins, and membranous vesicles appear in the supernatant plasma. The extent of these changes during refrigerated storage is not known. STUDY DESIGN AND METHODS: Membranous microparticles and changes in surface or total glycoprotein Ib (GPIb) were studied in platelet concentrates divided into aliquots stored at either 4 degrees C or 22 degrees C for 5 days. RESULTS: The refrigerated platelets showed greater loss of total GPIb, slightly less binding of monoclonal antibodies to surface GPIb, and reduced aggregation response to ristocetin relative to the paired platelet controls at 22 degrees C. Moreover, the platelets stored at 4 degrees C produced 45-percent more microparticles and 64-percent more platelet factor 3 activity in the supernatant plasma than were produced by the controls. These differences were augmented by warming both 4 degrees C- and 22 degrees C-stored platelets at 37 degrees C for 1 to 4 hours. CONCLUSION: Storage of platelets at 4 degrees C causes increased membrane vesiculation and accelerated loss of GPIb. The magnitude of these differences was small, but it may contribute to marked reductions in platelet survival in circulation. 相似文献
474.
目的:观察骨髓间充质干细胞移植治疗急性心肌梗死对血管内皮功能的影响。方法:实验于2005-09/2006-06在唐山工人医院中心实验室完成。①选用清洁级健康近交系SD大鼠40只,随机数字表法分为假手术组、模型对照组、干细胞移植组、细胞培养基组,10只/组。另取1只大鼠用于骨髓间充质干细胞的提取。②大鼠处死后无菌条件下分离股骨和胫骨,剔除肌肉、骨膜,剪一侧骨端,用10mL无血清DMEM低糖培养基冲出骨髓细胞后,收集冲洗液制成单细胞悬液,过滤离心,弃上清液,密度梯度法分离培养骨髓间充质干细胞。待细胞80%贴满培养瓶底时,用乙二胺四乙酸和胰蛋白酶混合消化传代。将4,6-二脒-2-苯基吲哚以50mg/L浓度加入第3代细胞培养基中,制成细胞悬液备用。③术前各组大鼠均行气管插管,建立急性心肌梗死模型,以远端供血区心肌组织颜色苍白、心电图检测Ⅱ导联ST段持续抬高为模型建立成功的标志。假手术组仅开胸予以前降支穿线但不结扎。④造模成功后1~3h,干细胞移植组用微量注射器吸取4,6-二脒-2-苯基吲哚标记好的第3代骨髓间充质干细胞悬液50μL,直接注入梗死区边缘的心肌组织。细胞培养基组按干细胞移植组的方法于相同部位注射等量无血清DMEM低糖培养基(pH值6.9)。⑤造模后4周处死各组大鼠,切取心脏组织,于梗死边缘区心肌组织制作切片,荧光显微镜下观察4,6-二脒-2-苯基吲哚标记的供体细胞。留取2mL全血,离心后抽取血清500μL,酶联免疫吸附法测定血清中细胞间黏附分子1与血管内皮细胞黏附分子1的含量。结果:40只大鼠均进入结果分析。①体外培养骨髓间充质干细胞的性状观察:从正常大鼠骨髓中分离培养的原代骨髓间充质干细胞,24~48h贴壁生长,短棒状;7~10d达到80%~90%融合;传至第3代骨髓间充质干细胞分布均匀,呈纺锤形。②各组心脏标本4,6-二脒-2-苯基吲哚标记移植细胞的存活状况:干细胞移植组可见成团及散在的4,6-二脒-2-苯基吲哚标记的阳性细胞,其余3组心脏标本中均未见荧光细胞。③各组大鼠血清中细胞间黏附分子1与血管内皮细胞黏附分子1的含量检测:与假手术组比较,模型对照组、细胞培养基组、干细胞移植组细胞间黏附分子1与血管内皮细胞黏附分子1的含量均明显升高(P<0.01或0.05);与模型对照组比较,干细胞移植组细胞间黏附分子1与血管内皮细胞黏附分子1的含量均有所降低[(3.37±0.14),(2.10±0.15)μg/L;(2.64±0.13),(1.74±0.06)μg/L;P均<0.05]。结论:骨髓间充质干细胞移植到实验性大鼠心肌梗死模型后成功存活,能降低血清中增高的细胞间黏附分子1与血管内皮细胞黏附分子1含量,提示骨髓间充质干细胞移植可能通过降低黏附分子的表达来改善血管内皮功能。 相似文献
475.
BACKGROUND: Patients with hemophilia B lack factor IX (F IX). These patients may become alloimmunized after the transfusion of F IX concentrates and may develop F IX inhibitors, which have been characterized as polyclonal IgG4 alloantibodies. Two cases in which F IX inhibitors caused difficulty in compatibility testing and antibody identification were encountered. It was hypothesized that, because F IX is present in normal plasma, it might be adsorbed by red cells in vivo and then be detected during antibody screening tests with serum containing F IX inhibitors. CASE REPORT: Sera from two African American half-brothers with hemophilia B were incompatible with all common and rare red cell phenotypes tested in the anti-human globulin test, but did not react with each other's red cells. The brothers' red cell antibodies were neutralized with both normal plasma and a commercially available F IX concentrate, which indicated that the red cell incompatibility was most probably caused by their F IX inhibitors. Red cells from an unrelated patient with hemophilia B and a very low titer of F IX inhibitor were tested against the half-brothers' sera and did not react. The compatible red cells from one of the half-brothers and the unrelated patient with hemophilia B adsorbed F IX from normal plasma or F IX concentrate after 37 degrees C incubation; this rendered them incompatible with the plasma containing F IX inhibitor from the other half-brother. CONCLUSION: F IX appears to be present on normal red cells and may be detected during compatibility and antibody identification procedures when serum or plasma containing F IX inhibitors is tested. 相似文献
476.
477.
Takaue Y; Reading CL; Roome AJ; Dicke KA; Tindle S; Chandran M; Devaraj B 《Blood》1987,70(5):1611-1618
The effects of colony-stimulating factors (CSFs), phytohemagglutinin (PHA), and hydrocortisone on the growth of human bone marrow hematopoietic progenitor cells (granulocyte-macrophage; GM) were analyzed in a limiting-dilution assay (LDA). Both low-density bone marrow cells separated by discontinuous Percoll gradients and a T cell- depleted and progenitor-enriched cell fraction obtained by the combination of counterflow elutriation centrifugation and Percoll gradients were examined in LDA. GCT (monocytoid cell line-conditioned medium containing GM-CSF), human placenta-conditioned medium, bladder carcinoma cell line 5637-conditioned medium (containing GM- and G-CSF), and recombinant CSF (G-CSF) directly induced proliferation of progenitors with single-hit kinetics. In some instances, however, PHA- stimulated lymphocyte-conditioned medium (containing G- and GM-CSF) showed deviation from single-hit kinetics, which demonstrated the presence of factor(s) suppressive to progenitor growth. In a T cell- depleted, progenitor-enriched fraction, PHA alone was found to suppress progenitor growth at a level as low as 100 ng/mL. The addition of hydrocortisone (10(-6) mol/L) increased the progenitor frequency but suppressed progenitor growth at 10(-4) mol/L. LDA appears to be a valuable method for exploring mechanisms of factors regulating hematopoietic cell growth. 相似文献
478.