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21.
Luis Cristovao Porto Michèele Chevallier Jean-Alexis Grimaud 《Virchows Archiv : an international journal of pathology》1989,414(2):129-134
Summary In the present study, hepatic venous distribution per unit of liver surface area on normal wedge biopsies from man (n=11) and baboon (n=8) were analysed and compared. Terminal hepatic veins (THV - man:n=100; baboon:n=200) morphometric size variables were obtained with a Leitz ASM 68K morphometric equipment. THV, defined as hepatic veins up to 150 m in internal diameter (ID), in the centrolobular position and with sinusoidal openings, represented 84% and 74% of hepatic veins of man and baboon, respectively. Four or more THV were generally found on 8 mm2 of liver surface. Transversely sectioned THV selected by the ratio IDminimum/IDmaximum >0.67, was found to be only 25% of the total THV. In baboon, THV merge with other terminal veins and the interlobular veins present sinusoidal inlets. The baboon THV wall surface (WS) and wall thickness (WT) values were higher than in man. Positive correlations between the number of mesenchymal cells (Mc) in the vein wall and wall surface of terminal hepatic veins (man: r= 0.79; baboon: r=0.83) and between wall surface and internal surface (IS) (man: r=0.80; baboon: r=0.72) were found. Two ratios were selected as the most reliable parameters: (1) for the THV wall rim, wall surface/internal surface (WS/IS - man: 0.43±0.16; baboon: 0.63±0.23), regarding transversely sectioned THV; and (2) for the evaluation of wall cell density (WS/Mc-man: 550±231; baboon: 558±183 m2/cell) as they did not depend on THV caliber.Dr. Porto was supported by a fellowship from MEC-CAPES, Brazil. A grant for morphometric equipment was obtained from the Fondation pour la Recherche Médicale and from the Societé d'Hépatologie Expérimentale, 77 rue Pasteur, Lyon, France 相似文献
22.
M. Fleischer W. Wippo H. Themann R. -S. Achatzy 《Virchows Archiv : an international journal of pathology》1980,389(2):205-210
Summary 15 biopsies of dilated and hypertrophied human left ventricles in mitral insufficient hearts were morphometrically investigated. On light and electron microscopical level the results were compared with those received from normally loaded human left ventricles and from hypertrophied human left ventricles found in hearts with aortic valve disease. The results demonstrate alterations when compared with the results from normally loaded left ventricles. The differences between normally loaded and volume loaded left ventricles are smaller than those in pressure loaded left ventricles from aortic valve diseased hearts.This work was supported gratefully by the Deutsche Forschungsgemeinschaft, SFB 104 相似文献
23.
Luis Cristovao Porto Michèle Chevallier Jean-Alexis Grimaud 《Virchows Archiv : an international journal of pathology》1989,414(4):299-307
Summary Alcohol induced perivenular fibrosis of terminal hepatic veins (THV) is claimed to be a precursor lesion leading to fibrosis development in man and baboon. The nature and significance of the THV lesions found in four baboons chronically fed with alcohol were studied in liver biopsies obtained during a three year period. The surface of THV wall and the number of mesenchymal cells were assessed with a semi-automatic image analyser. Histologically, THV were characterized as (a) phlebitic, in the presence of an inflammatory cell infiltrate involving the venous wall; (b) oedematous, when the connective tissue of the THV wall was disrupted or dissociated and (c) fibrotic, when perivenular scarring appeared as an increased rim. These lesions were present simultaneously and their intensity and distribution were independent of the duration of alcohol intoxication. Morphometric data obtained from these THV confirmed the thickening of the THV wall (WS/IS in: oedematous 1.05±0.36; phlebitic 1.65±1.04; fibrotic 1.47±0.36); and revealed an increased number of mesenchymal cells in fibrotic (439 m2/cell;p<0.01) and in phlebitic THV (510 m2/cell;p<0.05). A constant relationship was found between phlebitis and the presence of inflammatory infiltrate within the hepatic acini. Fibrotic THV was a less frequent finding and the lesion disappeared in the sequential biopsies of one of the baboons. In conclusion, THV lesions were heterogeneous and the collagen deposition in the THV wall was potentially reversible during the three year alcohol intoxication period, regardless the inflammatory reaction and, thus, did not indicate early irreversible hapatic fibrosis.Dr. Porto was supported by a fellowship from MEC-CAPES, Brazil. A grant for morphometric equipment was obtained from the Fondation pour la Recherche Médicale and from the Societé d'Hépatologie Expérimentale, 77 rue Pasteur, Lyon, France 相似文献
24.
We carried out a morphometric study on the myelinated fibers in the anterolateral funiculus (ALF) and lateral corticospinal tract (LCS) in the cervical segment of the spinal cord of 13 patients with classic amyotrophic lateral sclerosis (ALS), 6 of whom had been on a respirator: 5 age-matched subjects were used as controls. The results obtained revealed that: (1) the fiber-size distributions of the myelinated fibers in the ALF and LCS of the control subjects had peaks at 2 m; (2) there were marked and significant losses of large myelinated fibers in the ALF and LCS of ALS patients; (3) the patients who required respirator support showed more severe degeneration in the ALF than those who required none; and (4) the degree of myelinated fiber loss in the LCS did not correlate with either the illness duration or the history of respirator use. 相似文献
25.
Immunocytochemical studies of protamine-induced blood-brain barrier opening to endogenous albumin 总被引:1,自引:0,他引:1
The cellular mechanisms of blood-brain barrier (BBB) opening to endogenous albumin in the mouse brain after intracarotid infusion of solutions of protamine free base (PB) or protamine sulfate (PS) were studied using quantitative immunocytochemistry. Ultrathin sections of brain samples embedded at low temperature in Lowicryl. K4M were exposed to anti-mouse albumin antiserum followed by protein A-gold. Using morphometry, the density of immunosignals (gold particles per m2) was recorded over four compartments: vascular lumen, endothelial profiles, subendothelial space (including the basement membrane), and brain parenchyma (neuropil). In addition, the adsorption of endogenous albumin evidenced by the number of gold particles per m of the endothelial luminal plasmalemma was quantitatively evaluated. In the applied experimental conditions, PB was found to be strongly cytotoxic as indicated by the appearance of rapid degenerative changes and the disruption of the endothelial lining with concomitant clumping of the blood plasma. The action of PS was milder, offering a better opportunity for detailed ultrastructural and morphometric examination of brain samples during consecutive steps of PS action (2, 5, 10 and 30 min). As early as 10 min after infusion of PS solution, the adsorption of blood plasma albumin to the endothelial luminal surface was increased 2.5 times. Simultaneously, the immunolabelling of the endothelial profiles and subendothelial space was significantly increased. These results suggest that BBB disruption occurs through enhanced adsorption of albumin or albumin-protamine complexes to the luminal plasmalemma, followed by transendothelial vesicular transport, rather than through modification of interendothelial junctional complexes. This process appears to be focally disseminated throughout the cerebral vascular network and declines at 30 min following infusion of PS solution. 相似文献
26.
碱性成纤维细胞生长因子在人晶体上皮细胞的蛋白检测研究 总被引:5,自引:0,他引:5
研究成纤维细胞生长因子(basicfibroblastgrowthfactor,bFGF)对人晶体上皮细胞(humanlensepithelialcels,HLECs)的促增殖作用。方法:采用免疫组织化学检查(ABC法)来检测人晶体上皮细胞上bFGF蛋白水平,并用图像分析进行相对定量。结果:定性及定量地证明了人晶体上皮细胞有bFGF蛋白存在。结论:阐明了人晶体上皮细胞本身存在的bFGF以蛋白的形式参与了术后后囊混浊的形成。 相似文献
27.
A morphometrical analysis of the extent of hemosiderin deposits in 71 human skin wounds with post-infliction intervals between 2 days and 7 months was performed. Earliest positive findings were detectable in a lesion aged 3 days, and with increasing wound age an increase in the amount of hemosiderin occurred. A value of more than 20% of the microscopic field with hemosiderin deposits was found earliest 8 days after wounding and therefore the detection of considerable amounts of hemosiderin (arbitrarily defined as 20% or more of the evaluated area) indicates a minimum wound age of approximately 1 week. Since the extent of hemosiderin formation depends upon the extent of the initial hemorrhage and a physiological reduction in the amount of this pigment with advanced wound age, slight or absent hemosiderin deposits cannot provide information on the post-infliction interval. 相似文献
28.
Age-dependent effects of technical pentachlorophenol (PCP) on male rat livers were investigated after a 15 day treatment with PCP, 30 mg/kg/d body weight. The liver tissues were investigated morphometrically at light and electron microscopical levels. Statistically significant alterations of nuclei and organelles of the hepatocytes were described.This work was supported by the Deutsche Forschungsgemeinschaft — Biologie des Alterns — Th 83/14 相似文献
29.
D. De Craemer M. J. Zweens S. Lyonnet R. J. A. Wanders B. T. Poll-The R. B. H. Schutgens J. J. J. Waelkens J. M. Saudubray F. Roels 《Virchows Archiv : an international journal of pathology》1991,419(6):523-525
Summary We report very large hepatic peroxisomes (d-circle >1 m) in a patient with rhizomelic chondrodysplasia punctata and a patient with acyl-CoA oxidase deficiency. The effects of peroxisomal enlargement on the enzymatic activity are discussed. As increase in peroxisomal size is also reported in at least 12 other patients with peroxisomal disorders, we propose, a relationship between the enlargement of the organelles and their functional deficiency. 相似文献
30.
Anterior, middle, and posterior heights and A/P and M/P ratios were determined from T5 to L4 in 111 normal Caucasian Argentine
women from 20 to 70 years of age using dual energy X-ray absorptiometry (DXA) densitometry (Expert XL). Scanning time was
less than 1 minute and the semiautomatic analysis requires ∼5 minutes. The precision error for the measurements ranged from
2.2% to 4.6%. The absolute precision error for heights was 0.6 mm. The vertebral bodies tended to be significantly larger
in younger women than older women, especially for anterior and middle heights and the A/P and M/P ratios of the mid-thoracic
vertebrae (T6–T10). There were no significant differences between pre- and postmenopausal women in the lumbar vertebral heights.
It does not appear that this was a cohort effect because stature was identical in both age groups, and there was no age difference
in posterior height. The Expert-XL software normalized the vertebral height based on the average height of the L2-L4 segment
in order to minimize the influence of interindividual variation of body size. The average Z-scores for vertebral heights and
ratios provided by the software were close to zero indicating that the normalization procedure appropriately corrected for
smaller stature in Argentine women. Consequently, the reference values for morphometry X-ray absorptiometry (MXA) were appropriate
for our population. In summary, we found that (1) in ``normal' women the anterior heights of the thoracic vertebrae (and
therefore the A/P ratio) were higher in premenopausal than in postmenopausal women; and (2) the normalization approach corrected
for differences of vertebral height and allowed utilization of the manufacturers software in our population.
Received: 28 June 1999 / Accepted: 2 November 1999 相似文献