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目的:对比观察骨髓间充质干细胞移植前后脑梗死大鼠脑电图的变化。方法:实验于2002-09/12在解放军第三军医大学中心实验室及西南医院神经内科肌电图室完成。①实验分组:选取清洁级健康成年Wistar大鼠15只,随机数字表法分为干细胞移植组、模型对照组、假手术组,5只/组。②实验方法:另取2只健康幼年Wistar大鼠用于骨髓间充质干细胞的提取,联合采用密度梯度离心及贴壁法分离培养大鼠骨髓间充质干细胞,选取生长良好的1~3代细胞用于移植实验。干细胞移植组、模型对照组大鼠建立大脑中动脉栓塞模型。假手术组仅分离颈总动脉、颈外动脉和颈内动脉,不予结扎和放置线栓。造模后1周,干细胞移植组、假手术组大鼠行细胞移植,在立体定向仪定位下于脑梗死区(壳核)直接注射骨髓间充质干细胞悬液5μL,细胞浓度1×104μL-1,移植坐标为前囟前1.0mm,右旁开3.0mm,硬膜下5.0mm。模型对照组大鼠于相同部位注射等量不含细胞的磷酸盐缓冲液。③实验评估:采用脑电图机分别于造模前、造模后1周(移植前)、细胞移植后4周对各组大鼠进行脑电图检测。结果:15只大鼠均进入结果分析。①造模前基本节律为8~11Hz、15~30μV的α波,间或少量θ波,双侧对称。②造模后1周,假手术组异常率为0;模型对照组20%(1/5)轻度异常,80%(4/5)中度异常;干细胞移植组20%(1/5)轻度异常,60%(3/5)中度异常,20%(1/5)重度异常。③细胞移植后4周,假手术组脑电图恢复正常;模型对照组随术后时间的延长慢波有所减少,但仍可见到δ波、棘波、棘慢波的发放,至细胞移植后4周60%(3/5)轻度异常,40%(2/5)中度异常;干细胞移植组术后局限性慢波逐渐减少,基本节律全部恢复为α波,不对称的情况明显好转,至细胞移植后4周60%(3/5)轻度异常,以病灶侧局限性θ波较多为主,另外40%(2/5)基本正常。结论:动物实验显示骨髓间充质干细胞移植对脑梗死大鼠的脑电图背景节律有改善作用,一定程度上促进了神经系统功能的恢复。  相似文献   
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患儿,女,4岁,体质量19kg。生后4个月开始进行性面色苍白伴巩膜黄染,血红蛋白65g/L,白细胞和血小板均正常,血红蛋白电泳血红蛋白A48.1%、血红蛋白A24.2%、抗碱血红蛋白47.7%,基因型为β地贫纯合子,诊断为重型β地中海贫血,以间断大量输血维持生命。于2005-12-09在厦门大学附属中山医院血液科接受非亲缘性外周血干细胞移植。预处理方案采用常规氟达拉滨、白消胺、环磷酰胺三药联合方案,以环孢菌素A、霉酚酸酯、抗胸腺淋巴细胞免疫球蛋白联合预防移植物抗宿主病,供受者人类白细胞抗原高分辨全相合,ABO血型次要不合(O-A),输入CD34 干细胞11.4×106/kg。植入成功,移植后12d中性粒细胞>0.5×109L-1,移植后37d血小板>50×109L-1,移植后35d患者血型检测转变为供者血型,患儿血红蛋白达到100g/L的时间是28d,移植后患儿未再输血,血红蛋白维持130g/L以上,整个移植过程顺利,未出现严重感染和移植物抗宿主反应,随访18个月,患儿生活正常,发育良好。  相似文献   
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Background: In high altitude areas, patients report with irritation, redness and foreign body sensation in their eyes suggesting tear film abnormality due to low humidity and windy environmental conditions.  相似文献   
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OBJECTIVE: To evaluate surgical strategies for neuroendocrine pancreatic tumors (NEPT) in the light of the new WHO classification from 2004 and to draw conclusions for future surgical concepts. BACKGROUND:: The extent of surgical resection in primary and recurrent NEPT is unclear. METHODS: Between 1987 and 2004, 62 patients with sporadic NEPT were treated at our institution and sections from biopsy and resection specimen were histopathologically reclassified. Clinical presentation, surgery, metastases, and pattern of recurrence were related to survival. RESULTS: Fifteen well-differentiated tumors (WDT, 24%), 39 low-grade carcinomas (LGC, 63%), and 8 high-grade carcinomas (HGC, 13%) were identified. Median observation time was 30.5 months; 48 of 62 patients (78%) were surgically resected, and in 45 patients R0/R1 status was achieved. Overall 2- and 5-year survival in the latter group was 80% and 64%, respectively. Retrospective WHO classification revealed that organ-preserving segmental resections had been performed in 10 LGC and 1 HGC. These patients showed equal outcome as radically resected counterparts (n = 19). Liver and other organ metastases were present in 19 of 62 patients (31%), and resection was accomplished in 7 of 19 patients, which conferred better overall survival (P = 0.026, log-rank test); 21 of 45 R0/R1-resected patients (47%) suffered from recurrence, and reoperation was accomplished in 9 patients, which resulted in better overall survival (P = 0.066). CONCLUSION: Organ-preserving resections offer sufficient local control in LGC; therefore, radical resections do not seem to be justified. On the other hand, radical resection is indicated even in metastasized patients or in case of loco-regional recurrence. The silent and slow course of the disease facilitates long-term surgical control.  相似文献   
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OBJECTIVE: It was hypothesized that testing of ambulatory function and more demanding activities were more appropriate predictors of dynamic knee function before and after reconstruction of the anterior cruciate ligament than conventional measures of functional evaluation. It was assumed that assessment of dynamic plantar pressure distribution would represent a practical tool for guidance of the rehabilitation process after anterior cruciate ligament reconstruction. DESIGN: In a prospective study, 10 patients with isolated anterior cruciate deficiency were examined before and after replacement of the anterior cruciate (6, 12, 24 weeks) in a standardized technique. BACKGROUND: Today, functional assessment following anterior cruciate ligament reconstruction relies on clinical examination supplemented by instrumented testing of knee laxity and on isokinetic evaluation of muscle performance. Gait analysis has not been used as a quantitative measure of rehabilitation progress after surgery. METHODS: All patients were subjected to the same physiotherapy protocol. The clinical results were documented using the International Knee Documentation Committee (IKDC) protocol and the degree of knee laxity by an instrumented anterior drawer test. Muscular performance was evaluated by isokinetic testing. Dynamic pedography (EMED-SF 4) was performed to compare the non-injured and the operated leg during level walking and while descending stairs. RESULTS: Gait performance six weeks after surgery tended to be inferior to preoperative and late postoperative values. While the slight increase of maximum knee extensor torque in the operated leg and the improvement of the IKDC score during the rehabilitation period were not statistically significant, a significantly decreased gait asymmetry could be observed 12 weeks after surgery. The descending stairs test revealed functional deficits better than level walking. The latter test exhibited a strong correlation with the preoperative IKDC level and the maximum knee extensor deficit at 60 degrees /s. CONCLUSIONS: Dynamic pedography during level walking and while descending stairs is a valuable tool for monitoring the rehabilitation process after anterior cruciate ligament reconstruction. RELEVANCE: Due to the better resolution of functional deficits compared with indirect measures of function (isokinetic testing) assessment of the plantar pressure distribution may provide a more individualized adaptation for the rehabilitation program.  相似文献   
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The partial characterization and expression of the C1q receptor (C1q-R) in relation to other complement receptors present on the surface of neutrophils has been examined, as well as the effects of free C1q on cell function. A polyclonal anti-C1q-R antibody recognizes a 68-kD neutrophil surface protein. C1q-R expression was not upregulated upon warming, priming, or exposure to FMLP, but decreased after exposure to phorbol myristate acetate (PMA), because of shedding of the receptor into the extracellular medium, as detected by enzyme-linked immunosorbent assay. CR3 and CR1 expression was upregulated from intracellular pools after cell stimulation by PMA. No evidence of intracellular pools of C1q-R was found, as assessed by immunoblotting of subcellular fractions. But C1q-R appeared to be expressed early in cell differentiation, was detected on undifferentiated HL-60 cells, and like CR3 expression, increased upon 5 days differentiation towards a neutrophil lineage. However, C1q-R expression decreased upon additional culture, whereas CR3 expression continued to increase. A large variation in the percentage of peripheral cells expressing C1q receptors in donors was observed, ranging from 13% to 100%, contrasting with CR3 receptors that exhibited less variability. Interactions between free monomeric C1q and neutrophils were also studied. Incubation of stimulated neutrophils with 10 to 100 micrograms/mL C1q resulted in a further increase in CR3 expression and adherence to albumin-coated surfaces. Staphylococci opsonized with low quantities of C1q (0.1 to 1 microgram/mL) mediated a moderate and sustained respiratory burst in neutrophils, whereas a burst of similar magnitude was generated only with free C1q at concentrations 10- to 100-fold higher. Stimulation was only partially inhibited if cells were first treated with anti-C1q-R antibody, suggesting other C1q binding proteins may be present on the cell surface. In summary, neutrophil C1q receptor is approximately 68-kD, exhibits varying expression on different subjects, and is not upregulated from intracellular stores on exposure to soluble stimuli. Stimulated, but not resting, neutrophils selectively respond to raised levels of free C1q, resulting in altered cell function and enhanced CR3 receptor expression. These studies thus suggest complex roles for C1q in neutrophil function.  相似文献   
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