The Calculation of Radiation Dose from Distributed Sources of Tritium

Summary

Formulae derived by Rossi and Ellis (1950) for the calculation of radiation dose from distributed sources of beta-emitters have been made applicable to the case of tritium by a consideration of the appropriate value for the effective absorption coefficient employed in these expressions. An example is given of their application to the calculation of dose to a cell from tritium incorporated in the nucleus.     

如何正确运用t检验——两几何均值比较一般差异性t检验及SAS实现

本文目的是介绍几何均数以及两组近似对数正态分布数据几何均数的一般差异性t检验及SAS实现。首先对几何均数的概念、适用条件和计算公式进行介绍;并且将几何均数与统计学中常用的算术均数的特点进行比较;其次,呈现两组药物浓度数据,该数据近似服从对数正态分布,符合几何均数的适用条件,使用SAS的TTEST过程对两组几何均数的一般差异性进行t检验,并对相关结果进行解释和比较;最后,讨论几何均数使用时的注意事项。     

卵巢：“右男＆左女”规律应用于伴性遗传疾病“孕前O级干预”的设想

对于伴性遗传疾病，人类目前还无法以药物治疗或以基因干预来防治，除非染病者放弃生育权利。目前尝试的措施是采取分离X、Y精子和探测胎儿性别以终止妊娠。这些方法都在完善之中。这里报告的是：将卵巢“右男＆左女”分工规律的发现转化为伴性遗传疾病“孕前0级干预”的发明及其他“开拓性发明”的设想．也许能为人类性别分化研究提供新的视角。     

Aging-like Spontaneous Epigenetic Silencing Facilitates Wnt Activation,Stemness, and BrafV600E-Induced Tumorigenesis

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Autophosphorylation of the carboxyl‐terminal domain is not required for oncogenic transformation by lung‐cancer derived EGFR mutants

Aberrant activation of cancer‐derived mutants of the epidermal growth factor receptor (EGFR) is closely associated with cancer pathogenesis and is thought to be mediated through multiple tyrosine phosphorylations within the C‐terminal domain. Here, we examined the consequences of the loss of these C‐terminal phosphorylation sites on cellular transformation in the context of lung‐cancer‐derived L858R, exon 19 deletion and exon 20 insertion mutant EGFR. Oncogenic EGFR mutants with substitution of the 10 potential C‐terminal tyrosine autophosphorylation sites for phenylalanine (CYF10) were still able to promote anchorage‐independent growth in soft agar at levels comparable to the parental L858R or exon19 deletion or exon 20 insertion mutants with intact autophosphorylation sites. Furthermore, these CYF10 mutants retained the ability to transform Ba/F3 cells in the absence of IL‐3. Bead‐based phosphorylation and immunoprecipitation analyses demonstrated that key EGFR‐associated proteins—including Grb2 and PLC‐γ—are neither phosphorylated nor bound to CYF10 mutants in transformed cells. Taken together, we conclude that tyrosine phosphorylation is not required for oncogenic activity of lung‐cancer‐derived mutant EGFR, suggesting these mutants can lead to cellular transformation by an alternative mechanism independent of EGFR phosphorylation.     

Tumour-like lesions of the spleen

Tumour-like lesions of the spleen are very rare lesions but can cause diagnostic confusion due to their varying morphologic patterns. These lesions behave in a benign fashion. Included in this group are hamartomas, sclerosing angiomatoid nodular transformation (SANT), inflammatory pseudotumors, and possibly IgG4-related disease. Clinically, these lesions are often discovered incidentally on imaging or at autopsy. However radiological and morphological findings can be misleadingly worrisome. It is therefore important to be familiar with these lesions to distinguish them from malignant lesions.