Cooper R L, Chang D B, Young A C, Martin C J, Ancker-Johnson D
Biophys J. 1974 Mar;14(3):161-77. doi: 10.1016/s0006-3495(74)85904-7.
The pulsed-gradient spin echo nuclear magnetic resonance (PGSENMR) technique was used to measure restricted diffusion of water in three types of animal tissue: human blood plasma and red cells; rat and rabbit heart; rat and rabbit liver. Characteristic lengths (L) for restriction of diffusion are estimated from dependence on the measuring time. Limitations on the range of observable restrictive lengths (1.5-15 mum) are discussed.The decrease in diffusivity due to 1 mum alumina powder (volume fraction = 0.18) in glycerin/water mixtures agrees with the Wang theory assuming spherical particles and no hydration. The characteristic length (L approximately 4 mum) is larger than the particle size (1 mum) or separation (1.8 mum). Comparison of the diffusivities in tissues at short diffusion times with the Wang theory indicates some bound or trapped water.For packed red blood cells, a restriction (L approximately 2.3 mum) was attributed tothe red cell membrane. A permeability p approximately 0.014 cm/s may be estimated from the decrease in diffusivity. Average values of diffusivity ratio in heart were: 0.36 +/- 0.02 for rat; and 0.26 +/- 0.03 for rabbit; and in liver: 0.25 +/- 0.01 for rat; 0.25 +/- .04 for 10-day old rabbit; and 0.195 +/- 0.03 for 2-yr old rabbit. A restriction (L approximately 2.7 mum) in rat liver probably results from the mitochondria.
采用脉冲梯度自旋回波核磁共振（PGSENMR）技术测量了三种动物组织中水的受限扩散情况：人血浆和红细胞；大鼠和兔心脏；大鼠和兔肝脏。根据对测量时间的依赖性估算了扩散受限的特征长度（L）。讨论了可观测受限长度范围（1.5 - 15微米）的局限性。甘油/水混合物中1微米氧化铝粉末（体积分数 = 0.18）导致的扩散系数降低与假设为球形颗粒且无水合作用的王理论相符。特征长度（L约为4微米）大于颗粒尺寸（1微米）或间距（1.8微米）。短扩散时间下组织中扩散系数与王理论的比较表明存在一些结合水或被困水。对于 packed red blood cells，受限（L约为2.3微米）归因于红细胞膜。根据扩散系数的降低可估算渗透率p约为0.014厘米/秒。心脏中扩散系数比值的平均值为：大鼠为0.36 ± 0.02；兔为0.26 ± 0.03；肝脏中：大鼠为0.25 ± 0.01；10日龄兔为0.25 ± 0.04；2岁兔为0.195 ± 0.03。大鼠肝脏中的受限（L约为2.7微米）可能是由线粒体导致的。 （注：“packed red blood cells”这里可能有误，推测原文可能是“packed red blood cell”，翻译为“密集红细胞” ）
