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Under certain experimental conditions, bone marrow mesenchymal stem cells (MSCs) express neuronal phenotypes and neuronal
markers, which suggests that they could be used to treat various neurological diseases. In the present study, MSCs were isolated
from adult rat bone marrow, cultivated, and evaluated for neurotrophin expression profiles, as well as the potential to differentiate
into functional neuronal-like cells in vitro. MSCs from passage 5 were pre-induced with DMEM/F12 medium containing 10% fetal bovine serum (FBS) and 10 ng/mL bFGF (fibroblast
growth factor-2). Subsequently, a chemical inductor containing Dimethyl Sulphoxide (DMSO), Butylated Hydroxyanisole (BHA)
and forskolin were used to induce neural expression of MSCs. Expression patterns of nestin, NF-200, and GFAP at time points
before and after induction were detected by immunofluorescence. Nerve Growth Factor (NGF), brain-derived neurotrophic factor
(BDNF) expressions in MSCs were evaluated by RT-PCR. The whole-cell patch clamp technique was utilized to elucidate the electrical
behavior of MSC before and after 24-h differentiation induction. Immunofluorescence analysis revealed that MSCs expressed
nestin (57.1% ± 6.9%), but not NF-200 or GFAP. Following neural induction, the cells exhibited a neuronal-like appearance.
Nestin and NF-200 expression was positive in the neuronal-like cells, but GFAP expression was negative. After 6-, 12- and
24-h induction, the ratio of nestin-positive cells was 96.5% ± 1.9%, 88.1% ± 5.4%, and 33.5% ± 5.4%. NF-200 positive cells
were 90.1% ± 2.9%, 97.5% ± 1.3%, and 98.1% ± 1.6%, respectively. However, prior to induction, MSCs already expressed NGF and
BDNF. With a stimulus impulse of 40 mV, the density of the transient outward K current was (9.95 ± 4.85) pA/pF (n = 9) and (328.50 ± 30.62) pA/pF (n = 9) before and after induction, and the density of transient calcium ion currents was (−0.059 ± 0.027) pA/pF (n = 7) and (−6.66 ± 0.50) pA/pF (n = 7), respectively. Transient outward potassium currents and calcium ions currents gradually increased following induction.
In addition, MSCs isolated from bone marrow exhibited characteristics of neuronal progenitor cells and expressed neurotrophins.
These cells exhibited the capacity to differentiate into functional neuronal-like cells in vitro. These results suggested that MSCs express high levels of nestin and could be utilized for therapeutic strategies to treat
nervous system diseases. 相似文献
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很荣幸受邀参加今天的会议,与各位领导、专家、同仁一起研究讨论学术期刊特色栏目建设的问题;很荣幸作为协办单位的负责人在这里发言.在此,请允许我代表全国高等学校文科学报研究会,向组织发起并为本次会议付出心血的许昌市委和许昌学院的各位领导、各位同仁,表示衷心的感谢!
大家知道,高等学校社科学术期刊创办特色栏目,那是很久以前就有的事情了,但是,把特色栏目建设作为学术期刊发展的重要举措,把特色提高到学术期刊生存发展的高度上来考虑,却是这几年才有的事.十年前,在袁贵仁部长和我们高校学术期刊界老前辈的大力推动下,教育部启动了哲学社会科学名刊工程,其中一项重要内容,就是以名栏建设的形式,推动广大高校学术期刊提高质量,谋求发展. 相似文献
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近年来高水材料广泛用于煤矿巷旁充填、注浆加固和堵孔阻漏等工程领域,但易风化仍然是高水材料固有缺陷。为探究高水充填材料风化后的物理力学性质及风化机理,通过ETM力学试验系统对不同风化天数的高水材料进行研究。结果表明:高水材料风化主要是由于空气中的二氧化碳与钙矾石晶体发生反应,且随着风化天数的增加,自由水的流失与钙矾石晶体的逐渐解体会降低材料密实度,间接加速二氧化碳与钙矾石的反应,因此高水材料失水速率与劣化度随着风化天数增加而增大,且呈上升趋势;风化后的高水材料由表及里会形成风化层-过渡层-未风化层结构,风化层呈粉末状,受压即会破坏脱落,几乎不具备承载能力,但过渡层和未风化层仍然具备一定的承载能力;未风化的试件受压过程中会有水分溢出,风化后的试件无水分溢出。未风化的试件破坏形式属于劈裂破坏,风化后的试件破坏则都是在端部出现剪切破坏,剪切带周围会出现许多微裂隙。可见高水充填材料耐久性与其所处环境湿度密切相关。 相似文献
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“十五”时期,在市委、市政府正确领导下,天津市上下全面落买科学发展观,牢固树立“高水平是财富,低水平是包袱”的发展理念,顽强拼搏,扎实工作,信息化建设取得了非常显著的成绩。突出表现在以下几个方面:第一,信息基础设施建设实现跨跃发展。第二,初步建成具有天津特点的信息技术推广应用体系。 相似文献
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《中国高校科技与产业化》2009,(3):I0001-I0004
本项目属于石油与天然气工程领域(采掘业)。高水垂比大位移钻井技术是挑战钻井极限的前沿技术。当大位移井水平位移与垂深之比(水垂比)≥3,且水平位移≥3000米时,该井则称为高水垂比大位移井,钻井期间所面临的主要挑战是:浅层高造斜率、大斜度长裸眼的不稳定性与可延伸极限、井下的安全作业窗口、井下摩阻扭矩的严重性与控制能力、套管下入的难度和磨损,以及钻井设备的不适应性与综合运用能力等。 相似文献
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综采工作面破碎顶板预注浆加固技术研究 总被引:1,自引:0,他引:1
云驾岭矿通过对12114工作面破碎顶板范围采用新型高水材料注浆加固,良好地固结了破碎的顶板,解决了回采工作面受顶板破碎煤矸石影响而制约工作面回采推进的问题,同时保证了回采期间的安全生产。 相似文献