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451.
目的:探讨在大鼠脑缺血的情况下经尾静脉注射移植骨髓基质细胞的可行性,为骨髓基质细胞脑移植治疗提供一种简捷、安全、有效的途径。方法:实验于2005-10/2006-08在北华大学医学院实验中心完成。取1~2个月龄SD大鼠双侧股骨和胫骨,体外分离培养大鼠骨髓基质细胞。取体质量为280~320g的SD大鼠25只,采用颈内动脉线栓法制作大脑中动脉梗死模型,造模成功后在25只大鼠中随机盲抓分为2组:骨髓基质细胞移植组(n=15)、对照组(n=10)。骨髓基质细胞移植组经静脉缓慢推入含Hoeschst33342标记的骨髓基质细胞细胞悬液1mL(2.0×107个细胞),对照组用同样方法经尾静脉注入等量不含骨髓基质细胞的DMEM培养液作为对照。分别于移植后1d、7d、14d时间点对两组大鼠进行神经功能损害严重程度评分及大脑组织切片观察比较。结果:25只大鼠均进入结果分析。①各代细胞90%以上表达巢蛋白阳性。②与对照组相比,骨髓基质细胞移植组大鼠运动、神经功能恢复明显[骨髓基质细胞移植组:(6.10±2.96),(3.30±1.83),(2.10±1.20)分;对照组:(7.43±1.51),(6.14±1.35),(4.43±1.40)分,P<0.05]。③骨髓基质细胞移植组大鼠脑组织结构较清晰、完整;对照组大鼠脑组织破坏溶解,组织结构松散,细胞结构不完整,胞浆疏松,染色变浅,间质水肿。结论:通过静脉注射进行骨髓基质细胞移植,方法简便、安全,对神经损伤动物组织重建及神经功能有确切的修复效果。 相似文献
452.
目的:观察普伐他汀、阿司匹林联用对家兔颈动脉血管成形术后内膜增殖进展的影响及其作用机制。方法:实验于2002-03/12在北京中医药大学教育部中医内科学重点学科实验室完成。雄性日本大耳白兔30只,体质量1.8~2.0kg,动物适应性喂养1周后随机数字表法分为正常对照组(n=9)、假手术组(n=6)、模型组(n=9)、治疗组(n=6)。模型组和治疗组动物氯胺酮、速眠新混合肌注麻醉,沿气管正中切开皮肤,剥离颈总动脉,给予电刺激。术后第2天开始饲喂高脂饲料(胆固醇:0.7%,猪油:3%,普通饲料96.3%);正常对照组无任何干预措施;假手术组仅剥离颈总动脉,不做电刺激,喂高脂饲料;动物连续喂养8周后超声评价颈总动脉,根据B超选择颈总动脉有斑块或血流明显改变者作颈总动脉球囊扩张术。正常对照组、模型组、假手术组喂普通饲料,治疗组喂普伐他汀与阿司匹林含药饲料(普伐他汀5.046mg/kg,阿司匹林2.268g/kg),4周后测血脂和C-反应蛋白浓度、血清一氧化氮及转化生长因子β水平,观察颈动脉组织病理形态学改变,半定量分析增生内膜中胶原含量的变化,免疫组织化学方法分析增生内膜中巨噬细胞和平滑肌细胞阳性百分率。结果:纳入大耳白兔30只,正常对照组中途死亡1只,死因为牙齿畸型影响进食;模型组1只因电刺激8周时超声评价颈动脉未形成斑块及血流无明显改变而剔出实验,进入分析28只。与模型组比,普伐他汀与阿司匹林联用4周后,治疗组胆固醇及三酰甘油水平明显下降[(4.12±2.30),(0.74±0.17)mmol/L;(0.47±0.27),(0.39±0.14)mmol/L;P<0.05],血清C-反应蛋白水平和转化生长因子β水平均降低[(0.86±0.27),(0.57±0.30)mg/L;(3.45±0.77),(3.23±0.34)ng/L;P<0.05],一氧化氮水平升高[(41.79±35.78),(90.14±32.54)mmol/L;P<0.05],动脉内膜增殖程度明显减轻,管腔狭窄率降低,内中膜厚度及内中膜面积比降低[(71.91±14.90)%,(47.20±18.74)%;(0.41±0.17),(0.26±0.04)mm;1.66±0.63,0.78±0.34;P均<0.05],动脉内膜胶原含量减少(30.92±10.05,21.93±5.81,P<0.01),动脉内膜巨噬细胞阳性百分率降低[(13.94±4.91)%,(7.29±7.28)%,P<0.05],平滑肌细胞含量无明显差异(38.37±5.67,35.79±10.68,P>0.05)。结论:普伐他汀与阿司匹林联用具有抑制内膜增生和减少新生内膜胶原含量的作用,其机制与两药抑制炎症反应、保护内皮功能及抑制细胞外基质生成等有关。 相似文献
453.
Frederik H E Schagen Felix M Wensveen Jan E Carette Terence S Dermody Winald R Gerritsen Victor W van Beusechem 《Molecular therapy》2006,13(5):997-1005
Targeting adenovirus vectors (AdV's) for selective transduction of specific cell types requires ablation of native adenovirus tropism and introduction of a unique target-binding moiety. To bring these requirements within reach, we developed a novel strategy to target AdV's genetically that relies on replacement of the entire adenovirus fiber protein with a fusion molecule comprising the virion-anchoring domain of fiber and the oligomerization domain of reovirus attachment protein sigma1. The chimeric molecule forms trimers, is transported to the nucleus, and assembles onto the adenovirus capsid. In contrast to previously reported genetically targeted vectors, the AdV presented herein propagates efficiently without a requirement for complementing fiber. Due to ablation of the native adenovirus tropism, the infectivity of this AdV was at least 35-fold reduced on 293 cells. Importantly, a His tag incorporated into the chimeric attachment protein conferred His-tag-dependent tropism to the AdV, which resulted in a 12- to 40-fold greater transduction efficiency on two different cell lines expressing a His-tag-binding receptor. In addition, the infection efficiency was strongly reduced by preincubation with a His-tag-specific Ab. Thus, this sigma1-based chimeric attachment molecule provides a promising new platform for the generation of truly targeted AdV's. 相似文献
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459.
Visser LE Kyei-Faried S Belcher DW Geelhoed DW van Leeuwen JS van Roosmalen J 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2008,102(5):445-450
This study compares two antivenoms used to treat Echis ocellatus snake bite patients at Mathias Hospital, Yeji, central Ghana. FAV-Afrique antivenom (Aventis Pasteur) was given to 278 patients during 2001--2003, whilst Asna Antivenom C (Bharat Serum and Vaccines Ltd) was used in 2004 to treat 66 patients. The two groups had comparable patient attributes, time from snake bite to treatment and staff adherence to the tested treatment protocol. The antivenom C group required more repeat doses and twice the amount of antivenom to treat coagulopathy. Of greater concern, the antivenom C mortality rate was 12.1%, a marked rise from the 1.8% rate in the earlier FAV-Afrique antivenom group. In this study, antivenom C was ineffective as treatment for West African E. ocellatus snake venom. This illustrates the absolute need for regional pilot tests to assess the effectiveness of a new antivenom against local snake venoms before its sole and general distribution in a region is initiated. 相似文献
460.
Objective: Many cancer patients report cognitive changes following chemotherapy. In social psychology, there is ample evidence that psychological and physical complaints can increase with increased accessibility of relevant schemata. The accessibility of related concepts in memory may be facilitated through priming or by pre‐existing knowledge, resulting in an increase of reported complaints. We examined whether pre‐existing knowledge of chemotherapy‐associated cognitive problems and priming the ‘chemo‐brain’ schema increase the reporting of cognitive complaints. Methods: Two hundred and sixty‐one breast cancer patients were interviewed about cognitive problems and other cancer‐related symptoms. Preceding the interview, half of the patients were primed with an introduction letter to the study in which the occurrence of cognitive complaints and its relation with chemotherapy was explicated. The remaining patients received a neutral letter that did not mention this relationship. Results: Patients with pre‐existing knowledge about chemotherapy‐associated cognitive problems reported more cognitive complaints (M=3.04) than patients without this knowledge (M=2.21; p<0.001). The priming letter increased the reporting of cognitive complaints only for patients without a history of chemotherapy (p<0.05). All effects were independent of negative affect, age and education level. Conclusion: Our study shows that facilitating the accessibility of concepts related to chemotherapy‐associated cognitive complaints directly increases the reporting of such complaints, in particular in patients without firsthand chemotherapy experience. This increase in prevalence of cognitive complaints following a chronically or temporarily accessible ‘chemo‐brain’ schema has relevant implications for clinical practice and for scientific research in this area. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献