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LUO HaiYing WANG YunFang KONG Wei PEI XueTao 《科学通报(英文版)》2007,52(18):2449-2456
Today, liver transplantation (LT) is the only established treatment for end-stage liver diseases. The de- velopment of LT, including OLT, cadaveric LT, split LT, living donor LT (LDLT), brings hopes to patients with these diseases. However, increasing donor shortage, rejection and life-long immunosuppression with its side effects are the major limitations of this therapy strategy. Bone marrow-derived stem cells (BMDSCs) are capable of differentiating into hepatocyte-like cells and contribute to liver injury repair. The microenvironment of liver injury caused by rejection, ischemia/reperfusion, loss of liver mass, recurrence of HCV and "small-for-size syndrome" after LT can attract a variety of bone marrow-derived stem cell population to the peripheral circulation and then migration to the injury liver to promote the hepatic function restoration. Additionally, BMDSCs can also take part in the functional regeneration of living donor liver after LDLT. This participation in liver regeneration may be associated to the interac- tion between SDF-1and its receptor CXCR4, involving HGF, IL-8, MMP9, and VEGF/VEGFR-2. BMDSC with its bio-characteristics could maintain the allograft tolerance from different angles and in different ways. In conclusion, BMDSCs transplantation, as a new assistant therapeutic method for LT, will ex- pand the space of LT, and provide more survival opportunities for the patients suffering liver diseases in the future. 相似文献
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5,6-Dihydro-OSW-1 (1) was synthesized following our previous procedure for the total synthesis of OSW-1. This compound demonstrated slightly stronger potency than that of OSW-1 against the growth of cancer cells. 相似文献
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研究了新型无铅汽油添加剂甲基叔丁基醚(MTBE)、甲基叔戊基醚(TMAE)对正常人肝细胞系L-02的毒性作用,在较高浓度下,MTBE、TAME均对L-02正常人肝细胞的生长有影响,且TAME的毒性作用稍强,另外,用FT-IR法和^1H-NMR法研究了MTBE、TAME与人血红蛋白的体外作用,结果显示,MTBE、TAME与人血红蛋白无明显的直接作用。 相似文献
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介绍了TLC5 4 9带串行控制的 8位、4 0MHz单通道模数转换器的设计方法。常用的A D转换器件多数是并行输出 ,应用电路成熟 ,而带串行控制的转换器的设计方法少见。本文提出的串行控制单通道模数转换器设计方法在EDA实验系统上得到了验证 ,对相关电路设计具有一定参考价值 相似文献
7.
J.-M. Colet C. Piérart F. Seghi I. Gabric R.N. Muller 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1998,134(2):199-205
The relative contributions of intravascular and intracellular compartments to the proton transverse relaxation of the isolated and excised rat liver were determined during the phagocytosis of superparamagnetic particles. The evolution of the proton transverse magnetization of the organ perfused with increasing doses of starch-coated magnetic microspheres was followed up using a Carr–Purcell–Meiboom–Gill sequence with various echo times. From the multiexponential fit of the echo train, the amplitudes and the relaxation ratesR2of the liver tissue were obtained. The results clearly indicate that shortly after contrast medium administration, an internalization takes place which can be followed by the rapid and biphasic evolution of the transverse relaxation rate of the water protons. A very fast decaying component looking like an initial loss of the magnetization is observed together with an increase of the relaxation rate of the remaining water tissue. This regime is strongly dependent on both the echo time and the iron concentration, a behavior characteristic of the agglomeration of magnetic particles. The examination of the liver tissues by electron microscopy shows that this clustering arises in cytoplasmic vacuoles. 相似文献
8.
温健德 《淮北煤炭师范学院学报(自然科学版)》2006,27(2):71-74
人力资本是分析职业足球俱乐部的治理结构的起点,人力资本的各种特征所内含的不确定性将在足球俱乐部治理和俱乐部的持续发展中起核心作用.通过分析运动员的人力资本特征,主要包括:运动员是其人力资本的“自然”所有者和承担者,具有不可分性,走运动员的主动资产;运动员人力资本具有不完全替代性,并通过团队活动获得不同程度的垄断权力,有获取报酬递增的趋势;以及运动员人力资本的不确定性.俱乐部最重要的资产是运动员的人力资本资产,因此,俱乐部必须充分考虑运动员行为的不确定性,其治理结构必须符合人力资本的特征,激励合约必须面向未来. 相似文献
9.
完全学分制条件下高校学生团组织建设的探讨是一个崭新的课题。本文将简单对新形势下高校学生团组织面临的机遇和挑战以及完全学分制下高校学生团组织建设中的采用的对策进行阐述。 相似文献
10.
Katalin E. Kövér Dušan Uhr?&#x;n Victor J. Hruby 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1998,130(2):162-168
A pulsed field gradient version of the sensitivity-enhanced 2D TOCSY experiment is proposed which yields high-quality spectra with improved sensitivity and a minimum of two scans pert1increment. For rapid acquisition of 1D TOCSY spectra, the 1D DPFGSE–TOCSY experiment was modified to include phase-encoded multiple-selective excitation followed by a simple spectral editing. Combination of these two building blocks is used in a sensitivity-enhanced 2D analog of the 3D TOCSY–TOCSY experiment which provides an efficient tool for resolving severely overlapped signals of oligomers in short experimental time. 相似文献