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991.
992.
The concept that much of the cholesterol deposition in atherosclerotic plaque development is provided by ingress of blood-derived apo B-rich lipoproteins into the arterial intima is given support by the study of arterial apo B accumulation. To compare the arterial wall level of immunoreactive apo B during the progression of diet-induced atherosclerosis in two widely used animal models of atherosclerosis, rhesus and cynomolgus monkeys were fed an atherogenic diet for 4, 8, and 12 months and their abdominal aortas quantitated for apo B. Apo B was extracted from aortic intima-media homogenates in two forms: Tris-buffer extractable or ‘loosely bound’ and detergent (Triton X-100) extractable or ‘tightly bound’. The aortic extracts were quantitated for apo B by radial immunodiffusion, using goat antirhesus apo B along with serum LDL standards of the appropriate species diluted in the two extract solutions.

The control monkeys' aortas contained only buffer-extractable apo B. The atherosclerotic aortas of both species of monkeys progressively increased their levels of loosely bound and tightly bound apo B through 4, 8, and 12 months of atherogenic diet feeding, with the 8- and 12-month cynomolgus aortas containing much larger amounts of apo B than the rhesus aortas. These differences in aortic apo B content could be accounted for by the greater rate at which the cynomolgus atherosclerotic lesions developed at the later time points. When the total lesion apo B levels were correlated with representative morphometrically-quantitated histopathologic sections of the homogenized aortas, a highly significant correlation was seen between the total aortic apo B values and both the absolute area of the intimal lesions and the total area of oil red O stainable lipid in the lesions (P < 0.001). These data indicate that as atherosclerotic lesions become larger and richer in lipid with progression of the disease, the amount of apo B-associated lipoproteins which are deposited unmetabolized in the lesions increases. These lipoproteins are increased in both the tightly bound and loosely bound forms.  相似文献   

993.
雄激素致去势大鼠前列腺增生的组织形态学研究   总被引:19,自引:3,他引:16  
目的 :探讨前列腺增生大鼠前列腺的组织形态学改变。 方法 :采用SD大鼠去势后皮下注射丙酸睾酮法复制前列腺增生模型 ,用水取代法测量前列腺体积 ,苏木精 伊红染色观察前列腺增生组织结构 ,同时结合图像分析系统半定量检测前列腺增生内腺体、间质的形态计量学改变 ,并使用逐步引入剔出模型进行多元线性回归分析。结果 :与正常对照组比 ,模型组前列腺体积明显增大 (P <0 .0 1) ,腺腔扩张、间质增多 ;腺体面积、腺体相对总体积、单位体积内腺体平均直径、平均体积、平均表面积均明显增高 (P <0 .0 1) ,腺体数目、腺体数密度、腺体表面积 /腺体体积、腺体平均曲率显著减少 (P <0 .0 5~ 0 .0 1) ,体积密度无差异 ;间质面积明显减少 (P <0 .0 1) ,但间质相对总体积明显增加 (P <0 .0 5 )。回归分析结果 ,前列腺体积与腺体相对总体积和间质相对总体积呈明显正相关 (r分别为 0 .989和 0 .789,P均 <0 .0 0 1) ;前列腺体积与腺体平均体积呈明显正相关 (r =0 .82 4 ,P <0 .0 0 1)。 结论 :雄激素致去势大鼠前列腺增生以腺上皮增生为主 ,表现为腺腔的扩张 ,同时伴间质组织的增生  相似文献   
994.
In 31 cases of hepatocellular carcinoma, electron microscopic observation and morphometry on the cell organelles were carried out to evaluate the usefulness of electron microscopy for the diagnosis of well differentiated hepatocellular carcinoma. The cell organelles in well differentiated tumor cells were very similar to those in normal hepatocytes or hepatocytes with liver cirrhosis (LC). We found that in poorly differentiated tumor cells, the nuclear area, N/C ratio, nucleolar area, the amount of dispersed chromatin, and the number of free ribosomes had increased, but the cellular area, degree of nuclear roundness, and mitochondrial area had decreased. These results seem to indicate that electron microscopy is not as useful as light microscopy in the diagnosis of well differentiated hepatocellular carcinoma, but is useful in the study of poorly differentiated tumor cells, which indicated that the cell proliferation through mitoses was activated.  相似文献   
995.
Summary The spatial pattern of cell production and retinal growth were studied in Xenopus between stage 60 and two months after metamorphosis using 3H-proline and 3H-thymidine autoradiography. The position and the number of the ganglion cells labelled with 3H-thymidine were determined. The area of the unlabelled retina due to growth since 3H-proline administration at stage 60 was measured. Both retinal area measurements and counts of labelled ganglion cells showed 30–40% higher values in the temporal than in the nasal retinal half. The greater cell production and area accretion were even more pronounced between the temporal and the nasal retinal quadrants. The results on the temporoventral crescentic retinal growth rule out the possibility that from midlarval stages onwards the retinal and the tectal growth patterns are matched.  相似文献   
996.
正常肝,肝硬变和肝癌的计算机图像分析定量研究   总被引:1,自引:0,他引:1  
利用自动图像分析仪对正常肝组织、门脉性肝硬变、坏死后性肝硬变、癌旁肝硬变和肝细胞癌共49例标本进行了13项参数的形态定量研究。结果表明:大多数参数随着病变的发展而呈规律性变化。癌旁肝硬变的多数参数介于不伴肝癌的肝硬变和肝细胞癌之间,提示:(1)肝硬变与肝细胞癌密切相关;(2)癌旁肝硬变不同于不伴肝癌的肝硬变,与肝细胞癌的关系更为密切而具癌前病变性质。  相似文献   
997.
Summary The postnatal vascular growth in the cortex of vermis cerebelli folium IX of normal and pre- and postnatally protein-deprived rats was examined. The rate of increase in specific length of vessels seem to parallel the functional maturation of neurons in all cortical layers. From the first postnatal week there is a higher specific length of vessels in the Purkinje cell layer than in the adjoining parts of the molecular and granular layers. The results indicate that such differences are present also after the period of rapid vascular growth. Protein deprivation appears to affect the postnatal increase in specific length of vessels less in the Purkinje cell layer than in the granular and molecular layer where a significant reduction compared to controls was seen for the interval 7–20 days of age. At 90 days of age no significant differences were seen between control and protein-deprived rats.  相似文献   
998.
Summary The neuronal profiles of cell bodies in the facial nerve nucleus of adult rats were measured after partial peripheral nerve transsection. An image analyser was used for automatic recognition and morphometry. Based on classification of the neuronal profiles described in a previous paper, a morphometrical study was performed in order to analyse structural aspects of the retrograde reaction in quantitative terms. Beside the quantification of classical features of retrograde reaction (chromatolysis; nuclear eccentricity; increased basophilia; perikaryal, nuclear and nucleolar swelling), several reactive changes so far not recognized (karyoplasmic basophilia and granulation) were detected. These changes were interpreted as morphological correlates of regeneration in retrogradely reacting cells.  相似文献   
999.
A mathematical model for the stereological analysis of parallel-oriented, spheroidal nuclei has been applied to the basal layers of respiratory, metaplastic and dysplastic nasal epithelia. Nuclear profiles seen on tissue sections were measured with an automatic image analyser (IBAS). Nuclear profile area distributions were used to assess possible polyploidies. The result are compared to the histopathological grading, consisting of pseudostratified (respiratory), cuboidal, mixed cuboidal/squamous, squamous, and dysplastic epithelia. The estimated nuclear axis lengths, volumes, surface areas and volume/surface ratios are, in the great majority of cases, significantly smaller in pseudostratified or cuboidal epithelium than in squamous metaplasia and dysplasia. Correspondingly, the numerical density of the nuclei is lower in the latter cases, in which is also noted a smaller nuclear eccentricity. No significant difference is found between the nuclei of squamous and dysplastic epithelia. There is a clear correlation between the mean profile areas and the stereologically estimated volumes of the nuclei. When classifying the mean profile areas into four classes, a progressive shift from the smaller towards the larger size classes is observed when passing from pseudostratified to dysplastic epithelia, through the different metaplastic stages. The nuclear profile area plots often show several peaks, even in some pseudostratified and cuboidal epithelia, probably reflecting polyploidy. There is a marked tendency towards larger profile areas in squamous metaplasia and dysplasia. One histopathologically typical dysplasia showed only small-sized nuclei and another had a notable contribution of those in its profile area plot, in contrast with all the other dysplasias and squamous metaplasias, which displayed practically no small nuclei. The possible implications of the existence of "small-sized-nuclei-dysplasias" are discussed. The literature dealing with nuclear volumes or DNA quantities in putative preneoplastic situations in reviewed. Our method adds some valuable objective criteria to those used in classical histopathological grading. It should be possible to apply this method to other epithelial tissues.  相似文献   
1000.
Summary The applicability of morphometry in the cytological diagnosis of adenocarcinoma of the stomach was tested. Useful morphometric variables were extracted from 41 cases with known histology, and applied to 33 other cases: in all these cases the histological diagnosis were successfully predicted. Morphometry was applied an additional 39 cases selected for difficulties in cytodiagnosis. In the group of cases with suspicious cytology in particular, refinement of cytodiagnosis was achieved by the application of morphometry.  相似文献   
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