Objective To detect genetic alterations in pleomorphic xanthoastrocytoma (PXA), and to investigate the mechanism of development of this neoplasm.

目的研究多形性黄色星形细胞瘤（PXA）的遗传学异常，以探讨该肿瘤的发病机制。

youdao

pxa So what happens when we add a 2 p a and we subtract from it a 2 p x b, or the same with a 2 p y a subtracting a 2 p y b, is that we're actually going to cancel out the wave function in the center, so we now have 2 nodal planes.

当我们用,减去2pxb时，或者是2pya减去2pyb时，我们会消去,中间的波函数，所以现在我们有两个节面。

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