DiResta G R, Lee J, Lau N, Ali F, Galicich J H, Arbit E
Neurosurgical Research Laboratory, Memorial Sloan Kettering Cancer Center, New York, N.Y.
Acta Neurochir Suppl (Wien). 1990;51:34-6. doi: 10.1007/978-3-7091-9115-6_12.
A novel method to measure specific gravity (SG) of tissues, pycnometry (PYC), is described. This method utilizes a 2ml glass pycnometer filled with distilled H2O to determine the displacement volume of a tissue sample and an equation to compute SG from the sample's weight and the pycnometer's weight before and after adding the sample. The PYC method was validated using glass SG standards over the range 1.02-1.26, and against the column density gradient (DG) method using brain tissue from 250-300 g male rats. Factors which affect PYC accuracy, i.e. sample size, were also evaluated. Our results indicate that PYC SG values are highly correlated with the glass SG standards (slope = 1.0107, r = 0.9955, p less than 0.001), and highly correlated with DG when approximately 0.120 ml tissue samples are used in the pycnometer. The DG method was preferable to the PYC method, however, when small tissue samples, i.e. 0.60 ml or less, were used.
本文描述了一种测量组织比重（SG）的新方法——比重瓶法（PYC）。该方法使用一个装满蒸馏水的2毫升玻璃比重瓶来确定组织样本的排液体积，并通过一个方程式根据样本重量以及添加样本前后比重瓶的重量来计算比重。比重瓶法通过1.02 - 1.26范围内的玻璃比重标准进行验证，并与使用250 - 300克雄性大鼠脑组织的柱密度梯度（DG）法进行对比。还评估了影响比重瓶法准确性的因素，即样本大小。我们的结果表明，比重瓶法测得的比重值与玻璃比重标准高度相关（斜率 = 1.0107，r = 0.9955，p < 0.001），并且当在比重瓶中使用约0.120毫升的组织样本时，与密度梯度法高度相关。然而，当使用小组织样本，即0.60毫升或更少时，密度梯度法比比重瓶法更可取。
