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1.
C. Vyvyan Howard Luis M. Cruz-Orive Hiroshi Yaegashi 《Acta neurologica Scandinavica》1992,85(S137):14-19
The recently developed method of total vertical projections is illustrated to estimate the total dendritic length of a human Substantia Nigra neuron. Next, the length of the different orders of dendritic branches, and the mean segment length for each order - commonly regarded as important parameters in neuron physiology - are also estimated. Finally, it is shown how to estimate the mean dendritic length in a population of neurons from vertical slices of arbitrary and unknown thickness. Being unbiased and highly efficient, the proposed methods offer interesting alternatives to current procedures used for the metric analysis of neuron arborizations. 相似文献
2.
采用被公认的以γ-谷氨酰转肽酶阳性灶(GGT+)为观察终点的二乙基亚硝胺(DEN)致大鼠肝癌前病变的模型,对甘草甜素(GL)、纹股蓝总苷(绞股蓝总甙,GP)、茶多酚和柴胡水提取液等进行了筛选、并用体现学方法进行计量分析。结果显示,GL组的GGT+的面数由度(Na)为24.17±1.83/cm2(x±Sx,下同),体密度(Vv)为4.74±0.51%,数密度(Nv)为394.9±45.2/cm3;GP组的Na为25.35±2.64/cm2,Vv为5.93±0.75%,Nv为379.2±48.4/cm2,这两组的3个估计值与对照组的3个估计值(Na为37.21±2.56/cm2,Vv为8.12±0.70%。Nv为576.1±58.0/cm3)分别比较时均有显著性差异,说明这两种药物对DEN致肝癌发生有抑制作用,而茶多酚和柴胡水提取液则未显示抑制作用。 相似文献
3.
BACKGROUND/AIMS: Hepatocytes (HEP) have been the major target for structural quantification in the liver, but an estimation of their total number (N), their percentage in relation to the global number of liver cells and the evaluation of the percentage of binucleated hepatocytes (BnHEPs) have never been performed with modern design-based stereological techniques. The establishment of sound technical guidelines and baseline quantitative data in non-pathological conditions are relevant to properly evaluate HEP hyperplasia and BnHEP responses. METHODS: In this study, we combined immunocytochemistry with sound design-based stereology for estimating the N of HEP and the N of non-hepatocytic cells (NHCs). For obtaining systematic uniform random sections (30 microm thick), a smooth fractionator sampling scheme was applied to the liver of five male Wistar rats (3 month old). Those sections were immunostained with polyclonal antibodies against carcinoembryonic antigen. Because biliary canaliculi were then marked, an unequivocal counting of mononucleated hepatocytes (MnHEP) and BnHEP was allowed. RESULTS: The N of HEP was estimated to be 1.93 x 10(9), with a coefficient of error (CE) of 0.02, corresponding to 129 x 10(6) HEP/g of liver. BnHEP represented 26% of total HEP number. The N of NHC was estimated as 1.31 x 10(9) (CE=0.02). CONCLUSION: The strategy here presented provides a reliable method for accessing the N of HEP (distinguishing MnHEP from BnHEP) in situations in which these parameters are relevant, namely for evaluating the magnitude of an hyperplastic liver response from its very early onset. 相似文献
4.
The surface of the ovary has been found to be composed of two types of epithelial cells called A and B cells which are found in their own respective zones, the A and B zones. A quantitative study was undertaken to determine the mean cell volumes and cell ultrastructure. Ovarian biopsies were taken from six women and A and B zones, having been identified by scanning electron microscopy, were re-embedded for transmission electron microscopy. Stereological measurements using point sampled intercepts were made on vertical sections and showed that B cells are significantly larger than A cells. The volume weighted mean cell volumes of the A and B cells were 237.3 microns 3 and 676.8 microns 3 respectively. The volume fractions of the nucleus and mitochondria were similar in the two cell types. Although the vesicle content of each type was similar, a large variation between cases made the interpretation difficult. The stereological tools used in this study proved to be easy and efficient estimators of surface cell ultrastructure and give an important direction for ultrastructural research. 相似文献
5.
L. M. Nepomnyashchikh L. A. Semenova D. E. Semenov 《Bulletin of experimental biology and medicine》1989,107(4):546-551
Department of Pathomorphology and Morphometry, Institute of Clinical and Experimental Medicine, Siberian Branch, Academy of Medical Sciences of the USSR. Laboratory of Functional Morphology and pathology of the Cell, Institute of Cytology and Genetics, Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 4, pp. 477–481, April, 1989. 相似文献
6.
不同年龄人脑视皮质毛细血管密度的计量分析 总被引:1,自引:1,他引:1
本文应用碱性磷酸酶染色,按立体学方法观测了不同年龄(14岁以下儿童4例,成年人2例,60岁以上老人2例)共8例人脑视皮质有纹区各层毛细血管的密度(各层均取40个数据).结果:成年组视皮质第三层血管网3c亚层(位于皮质第Ⅳc层)毛细血管密度平均为1580.79±47.73mm/mm~3;儿童组为1087.19±44.90mm/mm~3;老年组为619.95±21.39mm/mm~3.经方差分析检验,P<0.01,说明在第三层血管网3c亚层三个年龄组之间具有非常显著性差异.讨论了各年龄组之间视皮质有纹区毛细血管密度差异与机能的关系. 相似文献
7.
对人类淋巴细胞性白血病MDR细胞系CEM/ADM及其亲代药敏细胞系CEM进行了超微结构的体视学定量比较。结果表明,CEM/ADM细胞分裂相较多见、核平均体积增大、核畸形严重、异染色质分布更散在、核仁异型性及边集较多见、多数细胞器不发达,说明CEM/ADM恶性程度更高,CEM/ADM线粒体平均体积增大与MDR主要机制──P-糖蛋白过度表达而致能量需求增加相关。 相似文献
8.
9.
介绍了测量颅内血肿体积的体视学法 ,并与尺量法进行比较 ,两种方法的测量结果无显著性差异 (P >0 0 5 ) ,但体视学法更加简便、快速。 相似文献
10.
本文介绍一种体视学方法~双平面成像体视法。这种方法只要从不同角度拍摄物体的两张照片,通过计算机的计算来确定物体的三维结构。目前流行的体视学方法,无论是从随机切片中统计出三维参数还是连续切片的三维重建,都相当于用一只眼睛观看大量景物之后所作的综合。本文提出的方法相当于人类用两只眼睛观察物体产生的立体视觉。该法所需信息量少(只需物体的两张照片),算法简便,计算结果精确。是一种值得推广的体视学方法。 相似文献