磁化率能够衡量磁珠向磁力架迁移的速度,其大小取决于铁含量和氧化铁的特性。Dynabeads磁珠的磁化率是指质量磁化率,单位可以是cgs单位/g或m^3/kg(国际单位制)。对于亚铁磁性和铁磁性物质,质量磁化率取决于磁场强度(H),这些物质的磁化强度与H不是线性关系,而是随着场强增加而趋于饱和。因此, Dynabeads磁珠的质量磁化率是在固定条件下由标准操作程序而测定的。我们产品目录中给出的质量磁化率是国际单位制。磁化率由从高斯(cgs、emu)单位向国际单位的转换,是通过“高斯系数(emu/g或cgs/g)x 4π x 10^-3”而实现的。所得单位也被称为合理化质量磁化率,与(国际单位制)无量纲磁化率单位有所区别。通常,质量磁化率可用来衡量在非均匀磁场中影响物体的力(Fz)。测定Dynabeads磁珠的质量磁化率时,首先对样本称重,然后将样本放置于已知强度的磁场中。随后,再次称重得到样本重量(F1),并与关闭磁场时样本的重量(F0)进行对比。使用下述公式计算磁化率:K x 10^–3 = [(F1-F0) x m x 0.335 x 10^6],K表示质量为m的样本的质量磁化率。最后,将磁化率转换为国际单位制。
'Inducible hematopoietic stem/progenitor cell lines represent a model for studying genes involved in self-renewal and differentiation. Here, gene expression was studied in the inducible human CD34+ acute myelogenous leukemia cell line KG1 using oligonucleotide arrays and suppression subtractive cloning. Using this approach, we identified Dlg7, the homolog of the Drosophila ... More
Infection of human CD34+ progenitor cells with Bartonella henselae results in intraerythrocytic presence of B. henselae.
Authors:Mändle T, Einsele H, Schaller M, Neumann D, Vogel W, Autenrieth IB, Kempf VA,
Journal:Blood
PubMed ID:15860668
'Although there is evidence that endothelial cells are important targets for human pathogenic Bartonella species, the primary niche of infection is unknown. Here we elucidated whether human CD34+ hematopoietic progenitor cells (HPCs) internalize B. henselae and may serve as a potential niche of the pathogen. We showed that B. henselae ... More
I branching formation in erythroid differentiation is regulated by transcription factor C/EBP{alpha}.
Authors:Twu YC, Chen CP, Hsieh CY, Tzeng CH, Sun CF, Wang SH, Chang MS, Yu LC,
Journal:Blood
PubMed ID:17855628
'The histo-blood group i and I antigens have been characterized as straight and branched repeats of N-acetyllactosamine, respectively, and the conversion of the straight-chain i to the branched-chain I structure on red cells is regulated to occur after birth. It has been demonstrated that the human I locus expresses 3 ... More
Early lymphoid progenitors in mouse and man are highly sensitive to glucocorticoids.
Glucocorticoids are extensively used in anti-inflammatory therapy and may contribute to the normal regulation of lymphopoiesis. This study utilized new information about the early stages of lymphopoiesis in mouse and man to determine precisely which cell types are hormone sensitive. Cycling B lineage precursors were depleted in dexamethasone-treated mice, while ... More
T cells modulate Epstein-Barr virus latency phenotypes during infection of humanized mice.
Authors:Heuts F, Rottenberg ME, Salamon D, Rasul E, Adori M, Klein G, Klein E, Nagy N,
Journal:
PubMed ID:24390326
Human B cells, the main target of Epstein-Barr virus (EBV), can display several types of latent viral protein expression, denoted 0, I, IIa, IIb, or III. Of these, only type III expression induces proliferation of cells in vitro. These latency types are present at specific stages of infection and are ... More