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1.
带浅静脉干逆行皮瓣早期微血管构筑变化的体视学研究 总被引:4,自引:0,他引:4
目的 探讨带浅静脉干的逆行皮瓣早期微血管构筑变化的特点以供临床实践参考。方法 应用生物体视学技术测量带浅静脉干皮瓣微血管体积密度,结合组织学观察,与不带静脉干皮瓣作对照比较。结果 带浅静脉干皮瓣组微血管密度整体水平高于不带静脉干皮瓣组(P〈0.05)。结论 浅静脉干的存在有利于皮瓣的血管化进程,保留浅静脉干对皮瓣成活有利。 相似文献
2.
Adaptation of the disector method to rare small organelles in TEM sections exemplified by counting synaptic bodies in the rat pineal gland 总被引:2,自引:0,他引:2
The disector is the only objective method for quantifying particles of variable size in a given volume. With this method, cell organelles are identified on adjacent sections, but only those present in one section are counted. When counting extremely rare structures in transmission electron microscope sections (physical disector), the usual procedure of counting on electron micrographs is limited for economic reasons (e.g. micrographs highly outnumbering the investigated structures). Hence, to apply this unbiased stereological method, a modification of the physical disector concerning 3 aspects has been developed. (1) The prerequisite of screening large corresponding tissue areas (here ∼65000 μm2 ) was fulfilled by examining tissue areas along the edges of ultrathin sections. (2) The size of the counting frame was determined by measuring the lengths of the section margins (minus a guard area) by means of a Morphomat. This value was multiplied by the width of the investigated tissue zone, corresponding to the diameter of the electron microscope viewing screen. (3) Disector counting was carried out simultaneously on both sections (bidirectional disector) to improve efficiency. In the present study tiny synaptic bodies (SBs) were quantitated by disector in a rat pineal gland, yielding ∼30 SBs/1000 μm3 . By contrast, single section profile counts of SBs amounted to 90 SBs/20000 μm2 . Since the presently described adaptation of the disector is time-consuming, it is proposed to determine a proportion factor allowing to estimate number of structures per volume based on single section profile counts. This would decrease the evaluation time by more than 50%. 相似文献
3.
用微量马桑内酯注入Wistar大鼠左侧前肢运动皮质,造成急性局灶型癫痫。用光镜、电镜和体视学方法研究其运动皮质第V层结构的改变。结果显示:癫痫大鼠运动皮质灶区、灶旁区的神经细胞数和胶质细胞数均分别比对照大鼠灶区和灶旁区显著减少;灶区神经毡中突触性终末数,显著减少;突触性终末的面积分数明显减少,而树突的面积分数无变化;神经胶质突起的面积分数增加。 相似文献
4.
以猪作为动物模型,通过分层抽样,制作各向同性切片,在图像分析仪下对超薄皮瓣的血管密度进行了观察。结果表明:超薄皮瓣血管密度于术后第5天开始出现显著性变化。这种变化首先出现在超薄皮瓣存活部分的远端,之后渐至近端。这种变化在超薄皮瓣血运重建过程中起主要作用。 相似文献
5.
The disector method was used to estimate the numerical density of neurons (number per unit volume) and their actual number per column (number under a given area of pial surface), in the occipital (monocular segment of the primary visual area, Oc1M), the parietal (somatosensory barrelfield area, Par1) and the frontal cortex (primary motor area, Fr1) of adult rat. Values were first obtained for all neurons in each layer, and then for GABA neurons as identified with postembedding immunocytochemistry on semithin sections. The numerical density of neurons in the frontal cortex (34,000/mm3) was significantly lower than in the two other neocortical areas (occipital: 52,000; parietal: 48,000/mm3). The GABA population showed a similar difference and consequently represented an equivalent proportion of total (15%) in the three cortical areas. Across layers, there was an alternate distribution of low and high density of neurons from layers II–III to VI in the three cortical areas, with the highest density in layer IV of the two sensory areas. The laminar changes in density of the GABA neurons were not as pronounced as those of the overall population. Consequently, the layers with the highest overall neuronal densities tended to have a lower proportion of GABA neurons and vice versa. There were more neurons under 1 mm2 of surface in the parietal (90,000) than the occipital or the frontal cortex (71,000), which was also true of the GABA neurons. The greater number of neurons per column in the parietal cortex was mostly imputable to layer IV, the main recipient of thalamic axons. Comparing these values from the rat with those previously obtained in cat and monkey, it seemed that the number of neurons per cortical column was the highest in the sensory area preferentially used by each species. 相似文献
6.
Sixty-two cases of breast pathology were randomly selected from the files of the Dunedin Public Hospital for evaluation of mean epithelial nuclear volume. The cases were comprised of both benign and malignant ductal epithelial disease, diagnosed in cytological smears or in histological sections. Nuclear volume in histological preparations was estimated by the stereological technique of point-line intercept measurements to derive volume-weighted mean volumes (vV). An index of the nuclear volume (Vi) of cytology smears was calculated from measurements of nuclear areas by either image analysis Vi(e) or point-line intercepts Vi(p). By all methods of analysis a clear distinction of nuclear volume was found between the benign [means for the cytology were 148 microns 3 (Vi(e)) or 246 microns 3 (Vi(p)), and 203 microns 3 (Vv) for the histology specimens] and malignant diseased cases [means for cytology: 524 microns 3 (Vi(e)) or 886 microns 3 (Vi(p)), and 587 microns 3 (vV) for the histology specimens]. 相似文献
7.
G. Chadi A. M?er L. Rosen A. M. Janson L. A. Agnati M. Goldstein S.-O. ?gren R. F. Pettersson K. Fuxe 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,97(1):145-158
Basic fibroblast growth factor (bFGF, FGF-2) is a trophic factor for neurons and astrocytes and has recently been demonstrated in the vast majority of dopamine (DA) neurons of the ventral midbrain of the rat. Potential neuroprotective actions of FGF-2 in the l-methyl-4-phenyl-l,2,3,6-tetrahydropyridine (MPTP) model have also been reported. The actions of the FGF-2 have now been further analyzed in a combined morphological and behavioural analysis in the MPTP model of the adult black mouse, using a continuous human recombinant FGF-2 (hrFGF-2) intraventricular (i.v.t.) administration in a heparin-containing (10 IU heparin/ml) mock cerebrospinal fluid (CSF) solution. Tyrosine hydroxylase (TH) immunocytochemistry in combination with computer assisted microdensitometry demonstrated a counteraction of the MPTP-induced disappearance of neostriatal TH-immunoreactive (ir) nerve terminals following the FGF-2 treatment. Unbiased estimates of the total number of nigral TH ir neurons, using stereological methods involving the optical disector (Olympus), showed that the MPTP-induced reduction in the number of nigral TH ir nerve cell bodies counterstained with cresyl violet (CV; by 56%) was partially counteracted by the FGF-2 treatment (by 26%). The behavioral analysis demonstrated an almost full recovery of the MPTP-induced reduction of the locomotor activity after FGF-2 treatment. This action was maintained also 1 week after cessation of treatment. The hrFGF-2 produced an astroglial reaction as determined in the lateral neostriatum and in the substantia nigra (SN) far from the site of the infusion, indicating that the growth factor may have reached these regions by diffusion to activate the astroglia. Immunocytochemistry revealed FGF-2 immunoreactivity (IR) in the nuclei of the astroglia cell population in the dorsomedial striatum and the microdensitometric and morphometric evaluation demonstrated an increase in the number, but not in the intensity, of these profiles on the cannulated side, suggesting the possibility that hrFGF-2 stimulates FGF-2 synthesis in astroglial cells with low endogenous FGF-2 IR. These results indicate that hrFGF-2, directly and/or indirectly via astroglia, upon i.v.t. infusion exerts trophic effects on the nigrostriatal DA system and may increase survival of nigrostriatal DA nerve cells exposed to the MPTP neurotoxin. 相似文献
8.
Robert Norlund Kjell Grankvist Lena Norlund Inge-Bert Täljedal 《Virchows Archiv : an international journal of pathology》1984,404(1):31-38
Summary Stereological techniques on electron microscopy micrographs were used to evaluate the morphological changes of cultured islet cells that had been exposed to alloxan or 6-hydroxydopamine.Trypan Blue exclusion by cells cultured for 3 days indicated that the cells were 100% viable. Electron microscopy revealed that nearly all of the surviving cultured cells were cells.Exposure to 5 mmol/l alloxan or 1–5 mmol/l 6-hydroxydopamine for 10 or 30 min caused a general swelling of the cultured cells with a concomitant swelling of mitochondria and nuclei. The size of the secretory granules was not affected by the drugs. Only 3–10% of the cells excluded Trypan Blue after exposure to 5 mmol/l alloxan or 6-hydroxydopamine.The data conform with the hypothesis that a primary action of alloxan and 6-hydroxydopamine is at the plasma membrane level of cells.Abbreviations and definitions
A
cell
Cell profile area (µm2), surface area of one cell section surface
-
V
n
Nuclear volume density (%), number of points over the nucleus divided by the number of points over the total cell area × 100
-
V
m
Mitochondrial volume density (%), number of points over mitochondria divided by hits over the cytoplasm (points over the cell minus points over the nucleus) × 100
-
V
g
Granular volume density (%), number of points over granules divided by hits over the cytoplasm × 100 相似文献
9.
Hiroshi Mori M.D. Ryo Fukunishi Motohiro Fujii Kohsuke Hataji Tsuneo Shiraishi Keishi Matsumoto 《Virchows Archiv : an international journal of pathology》1978,380(1):1-9
Summary Reinke's crystals in human Leydig cells were analyzed stereologically to assess their functional role. Testicular tissues were taken from seven older men (57–82 years old) with prostatic carcinoma and also from seven younger men (26–38 y.o.) complaining of male infertility. Sections 0.5 m thick, stained with toluidine blue or Heidenhein's iron-hematoxylin were examined by a point-counting method and with a Particle Measurement Computor System (MC). When the patients were grouped by age, the mean crystal volume, the number of crystals per cell, the volume of crystals per cell and the volume ratio of crystals to cell were significantly larger in the older age group than in the younger age group. In particular, the latter three variables correlated well with the age of subjects, with correlation coefficients of r=0.66–0.85. On the other hand, none of these variables had any correlation with the concentration of plasma testosterone. These results indicate that Reinke's crystals can be considered as degenerative products in cell life but not as facultative constituents for testosterone production.Supported in part by a grant from Medical Foundation of Ehime, Japan 相似文献
10.
M. E. De Paepe Konstantinos Papadakis Brian D. Johnson Francois I. Luks 《Virchows Archiv : an international journal of pathology》1998,432(1):7-16
Tracheal occlusion in utero has been shown to cause accelerated fetal lung growth and is now being considered as a therapeutic
modality for pulmonary hypoplasia. We report the effects of tracheal ligation on the surfactant-producing type II pneumocyte
population. Three groups of fetal lambs underwent tracheal ligation of 2 weeks’, 4 weeks’ and 6 weeks’ duration, respectively,
and all were sacrificed at 136 days’ gestation (9 days pre-term). Nonoperated twins served as controls. The type II pneumocyte
population was studied morphometrically using a combination of anti-surfactant protein B immunohistochemistry and computer-assisted
stereologic morphometry at light and electron microscopic levels. Single-factor ANOVA was used for statistical analysis. Two
weeks of tracheal ligation resulted in doubling of the total lung volume as a result of airspace distension and, to lesser
extent, growth of the tissue compartment. With increasing duration of tracheal ligation, there was no additional lung growth.
However, more prolonged tracheal occlusion was found to result in significant reduction of the surfactant system, as reflected
in the marked decrease of total pneumocyte type II volume (3.14 cm3, 0.95 cm3, and 0.46 cm3, after 2, 4, and 6 weeks of ligation, compared with 5.96 cm3 for controls) and total pneumocyte type II number (13.9 × 109, 3.8 × 109, and 2.4 × 109, compared with 53.2 × 109 for controls). Ultrastructural analysis of the type II cells in obstructed lungs showed vacuolar degenerative changes that,
after 6 weeks of ligation, were apparently irreversible. In utero tracheal ligation causes fetal lung hyperplasia, but results
in reduction of and injury to the surfactant-producing cell population. Before tracheal occlusion can find widespread clinical
application, its pathophysiology needs to be further elucidated.
Received: 30 April 1997 / Accepted: 10 July 1997 相似文献