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41.
42.
Serial in vivo MR tracking of magnetically labeled neural spheres transplanted in chronic EAE mice. 总被引:5,自引:0,他引:5
Tamir Ben-Hur Ruud B van Heeswijk Ofira Einstein Michal Aharonowiz Rong Xue Emma E Frost Susumu Mori Benjamin E Reubinoff Jeff W M Bulte 《Magnetic resonance in medicine》2007,57(1):164-171
Neural stem cell (NSC) transplantation has been shown to attenuate the severity of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Central to the future success of NSC transplantation in MS is the ability of transplanted cells to migrate from the site of transplantation to relevant foci of disease. Using magnetically labeled mouse neurospheres and human embryonic stem cell (hESC)-derived neurospheres, we applied serial magnetic resonance imaging (MRI) to assess the biodynamics of transplanted cell migration in a chronic mouse EAE model. Magnetic labeling did not affect the in vitro and in vivo characteristics of cells as multipotential precursors. Cell migration occurred along white matter (WM) tracts (especially the corpus callosum (CC), fimbria, and internal capsule), predominantly early in the acute phase of disease, and in an asymmetric manner. The distance of cell migration correlated well with clinical severity of disease and the number of microglia in the WM tracts, supporting the notion that inflammatory signals promote transplanted cell migration. This study shows for the first time that hESC-derived neural precursors also respond to tissue signals in an MS model, similarly to rodent cells. The results are directly relevant for designing and optimizing cell therapies for MS, and achieving a better understanding of in vivo cell dynamics and cell-tissue interactions. 相似文献
43.
44.
V. Prát M. Horčičková K. Matoušovic M. Hatala 《International urology and nephrology》1990,22(3):201-207
Fifty-four patients with complicated UTI were administered ciprofloxacin in doses of 500 mg (30 subjects) and 250 mg (24 subjects)
at 12-hour intervals. While a positive effect was noted in 96–100% upon termination of therapy, the effect was still present
3 weeks later in 90% of the high-dose, but only in 71% of the low-dose group. In 23 patients with uncomplicated UTI, a positive
effect of the three-day therapy with 100 mg of ciprofloxacin at 12-hour intervals was observed in 91% of subjects.
Intolerance to the agent was found in one case only. Development of resistance to ciprofloxacin was not observed. 相似文献
45.
用基因工程重组的丙肝抗原包被于硝酸纤维素膜,建立了检测丙肝IgG抗体的斑点免疫渗滤法。与ELISA试剂盒进行双盲式同步测定,二法检验结果差异无显著性。渗滤法简便快速,适用于各级医院,有很强的推广价值。 相似文献
46.
47.
A. Dmoszyńska-Giannopoulou L. Janicka B. Sokołowska A. Ksi⇂żek G. Orłowska K. Janicki 《International urology and nephrology》1990,22(6):561-566
In 30 patients on chronic haemodialysis treatment the platelet activity and function were studied before and during antiplatelet
therapy with alpha-tocopherol and sulphinpyrazone. In both kinds of treatment a significant decrease of ADP-induced and spontaneous
aggregation was observed. Sulphinpyrazone exerts an inhibitory effect not only on platelet aggregation but also on platelet
factor 3 and provokes a significant prolongation of the bleeding time. 相似文献
48.
过氧化氢对白色念珠菌DNA破坏的研究 总被引:1,自引:0,他引:1
本文用热变性温度法研究一定浓度 H_2O_2对 C.albicans DNA 破坏作用。结果表明,经6%和10%H_2O_2处理后,C.albicans DNA G c Mol%(分别为28.1±0.82和14.4±1.51)显著低于对照 DNA G C Mol%(85.9±0.62),并推断 H_2O_2可能作用于 C.albicans DNA 碱基以及其间的氢键上;DNA 电泳图谱发现,经3%和6%H_2O_2处理的 C.albicans DNA 电泳带明显不同于对照,提示 H_2O_2更易造成 C.albicans DNA 核苷酸链的降解或断裂.H_2O_2对 C.albicans DNA 的破坏,增强了其杀菌作用。 相似文献
49.
During reproductive maturation of female insects, the acquisition of sexual receptivity is coordinated with ovarian development. Juvenile homone regulates vitellogenesis in the ovaries, but the action of this hormone in the development of sexual behavior is less well-understood. A strain ofDrosophila melanogaster carrying a mutation in theapterous gene(ap
4) was known to exhibit arrested vitellogenesis (rescuable by applying exogenous juvenile hormone), sterility of both sexes, and a deficiency of juvenile hormone. In this study, we examined the effects of mutations ofap on female receptivity and its relationship to juvenile hormone. We observed abnormally low female receptivity in homozygousap strains, and heteroallelic combinations ofap mutations exhibited low receptivity. For female receptivity,ap showed no dominance (i.e.,ap/ap
+ was intermediate betweenap/ap andap
+/ap
+). Low receptivity mapped genetically to theap locus. The reduction in female receptivity in these mutants is positively correlated with levels of juvenile hormone synthesized by their corpora allata.This work was supported in part by The Scheinfeld Center for Humans Genetics in the Social Sciences (J.R.), The National Science Foundation (BNS-882 1339 to J.R.), BARD (No. IS-1664-89R to D.S.), The Israel Cancer Research Fund (grant to D.S.), The Rekanati Foundation of Tel Aviv University (grant to D.S.), and The Israeli Fruit Council (award to M.A.) 相似文献
50.
1H and 13C NMR signals of tri(propylene glycol) and of its benzoate and phenyl urethane were assigned by means of 1D and 2D NMR methods such as super-selective long-range INEPT, H-H COSY, H-C COSY and H-H-C RCT spectra. Both 1H and 13C NMR were used as methods for the determination of primary and secondary hydroxy end-groups and of their degree of conversion. 13C NMR was found to be a reliable and universal method of end-group determination even for cases where 1H NMR fails due to the presence of water in the sample or to the nature of the reactant. The results are applied to the analysis of poly(oxypropylene)s with two or three hydroxy end-groups and their derivatives. 相似文献