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1.
The calcified layer of articular cartilage is known to be affected by age and mechanical factors that may play a role in the development of arthrosis. Because these factors are also related to subchondral remodeling and sclerosis, a morphometric study was carried out in fluorochrome-labeled animals to determine whether the level of subchondral remodeling affected the thickness of the calcified cartilage layer and its irregularity and vascularity at the interface with subchondral bone. These parameters were also studied at a site of increased mechanical stress. The area and thickness of the calcified cartilage layer was determined in basic fuchsin-stained ground sections (120 microm). The irregularity of the chondro-osseous interface was expressed as the ratio of its length to that of the relatively straight tidemark (Int/Tid) and the number of abutting vessels with and without fluochrome labels were counted (N.Ves/Tid,%L.Ves/Tid). These were compared with single-labeled surface (sLS/BS, %) in subchondral bone, which was used as an index of remodeling. In a group of 12 horses, in which one carpus had an osteochondral fragment surgically created 10 weeks earlier, there was activation of subchondral remodeling in the third carpal bone opposite the fragment. An increase in %L.Ves/Tid (p < 0.01) at the interface was correlated with the increase in %sLS/BS in subchondral bone (r=0.431, p=0.035). The number of abutting vessels and the interface irregularity were not significantly changed on the fragmented side. In the metacarpal condyles from the fetlock joints of the same horses there were no differences associated with the surgically created fragment in the carpus and no correlation of %L.Ves/Tid with subchondral %sLS/BS. At a site where mechanical overload and traumatic osteochondrosis is known to occur on the palmar surface, the calcified cartilage was thinner, and the interface irregularity tended to be greater. These findings indicate that activated subchondral remodeling extends to involve the calcified layer, but the thickness and irregularity of the calcified cartilage are not consistently related to current subchondral remodeling. At sites of mechanical overload the calcified cartilage was thinner and the interface tended to be more irregular, suggesting previous increased remodeling. 相似文献
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TR Oegema RJ Carpenter F Hofmeister RC Thompson 《Canadian Metallurgical Quarterly》1997,37(4):324-332
The zone of calcified cartilage (ZCC) forms an important interface between cartilage and bone for transmitting force, attaching cartilage to bone, and limiting diffusion from bone to the deeper layers of cartilage. The height of the ZCC is a relatively constant percent of articular cartilage and the height is maintained by a balance between progression of the tidemark into the unmineralized cartilage and changing into bone by vascular invasion and bony remodeling. During its formation, the cells that form the ZCC have properties similar to the cells of the growth plate. In the adult, the ZCC becomes quiescent but not inactive. The ZCC may be reactivated in osteoarthritis and may progressively calcify the unmineralized cartilage. This might contribute to cartilage thinning which would increase the concentration of forces across the uncalcified cartilage leading to more damage. Although the subchondral bony plate remodels extensively in osteoarthritis, there is little evidence that a change in the biomechanics of the plate directly initiates the osteoarthritic process in cartilage. However, increased repair by endochondral ossification of vertical cracks in the ZCC that penetrate into the marrow space could contribute to progression via changes in the ZCC. 相似文献
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Injuries of the nasoethmoid-orbital (NEO) region are associated with midfacial fractures or fractures of the frontobase in over 90% of all cases. In up to 70% fractures of the skull base run through the roof of the ethmoidal bone or the lamina cribrosa. There are different surgical approaches for the treatment of these complex fractures. Between 1990 and 1997 50 patients with midfacial fractures in association with NEO fractures were treated in the Klinik für Mund-, Kiefer- und Gesichtschirurgie, Kantonsspital Luzern, Switzerland. Of these, 25 had suffered midfacial fractures combined with fractures of the nasoethmoid-orbital and frontobasal region and were treated via a transcranial approach. The other 25 patients with midfacial and NEO fractures without involvement of the frontobasis were managed by subcranial incisions. A total of 47 patients were followed up for up to 4 years. The results were reevaluated retrospectively. There was no case of secondary liquorrhea, intracranial or ethmoidal infection. Our therapeutic concept of transcranial and subcranial management of NEO fractures in combination with frontobasal and midfacial fractures is demonstrated. 相似文献
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179 undergraduates completed a social network list, an inventory of socially supportive behaviors, the Extraversion and Neuroticism scales of the Eysenck Personality Questionnaire, the Marlowe-Crown Social Desirability Scale, and the UCLA Loneliness Scale. Both social network variables and individual differences measures (extraversion, neuroticism, and self-disclosure) were predictive of self-reported loneliness in Ss. Of the social network variables, the density of the network showed the strongest and most consistent relation to loneliness, with denser networks being associated with less loneliness. Both extraversion and neuroticism were correlated with loneliness. The relation of extraversion and loneliness was mediated largely by social network variable; partialing out variance attributable to the social network variables reduced the relation of extraversion and loneliness. The relation of neuroticism and loneliness, however, was not mediated by social network variables. Results support W. H. Jones's (1982) conclusion that lonely college students are not necessarily socially isolated. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The relation between early fantasy/pretense and children's knowledge about mental life was examined in a study of 152 3- and 4-year-old boys and girls. Children were interviewed about their fantasy lives (e.g., imaginary companions, impersonation of imagined characters) and were given tasks assessing their level of pretend play and verbal intelligence. In a second session 1 week later, children were given a series of theory of mind tasks, including measures of appearance-reality, false belief, representational change, and perspective taking. The theory of mind tasks were significantly intercorrelated with the effects of verbal intelligence and age statistically controlled. Individual differences in fantasy/pretense were assessed by (1) identifying children who created imaginary characters, and (2) extracting factor scores from a combination of interview and behavioral measures. Each of these fantasy assessments was significantly related to the theory of mind performance of the 4-year-old children, independent of verbal intelligence. 相似文献
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AW Jay 《Canadian Metallurgical Quarterly》1976,262(2):447-458
The osmotic swelling to haemolysis of individual red blood cells by isosmotic thiourea has been studied using microcine photography. 2. Crenation occurs immediately upon addition of isosmotic thiourea. The cell becomes a crenated sphere without volume decrease. 3. Subsequently, the cell volume increases linearly with time with maximum swelling occurring at about 102 sec which is 81% of the total haemolysis time. 4. At maximum swelling, the cell volume is 92% greater than the initial cell volume. This volume increase is about double that measured with other permeating substances. 5. The much larger maximum volume implies that thiourea increases the area of the cell membrane. This increase varies from 0 to 75% for individual cells, with a mean of 22%. 6. Membrane expansion varies inversely as the initial cell membrane area and cell volume (r=0-790). 7. Using the increased surface area, increased maximum volume and the swelling time, the mean permeability is calculated to be 5-52 X 10(-7) cm/sec (S.D. of mean=+/-1-19 X 10(-7) cm/sec). The distribution of permeabilities represents a normal distribution. 8. The pre-lytic potassium loss ranged from 0 to 36% with a mean value of 16-5%. This is consistent with values reported in the literature for slow haemolysis. As with other permeants the distribution is skewed towards lower values. 9. Membrane permeability of individual cells varies with the amount of membrane expansion observed. Coefficient of correlation between permeability and expansion index is 0-674. 10. There is no correlation between permeability and the reciprocal of the haemolysis time (r=-0-035). The correlation between permeability and the reciprocal of the swelling time is also poor (r=0-303), probably owing to the variability in membrane expansion by thiourea in individual cells. 11. As has been shown previously for faster permeants, the permeability coefficient cannot be calculated from the haemolysis time. Because thiourea alters the membrane area and the haemolytic volume, the coefficient cannot be calculated from the swelling time unless the changes in the membrane area are also taken into account. 相似文献
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The structure of the keratan sulphate chains attached to fibromodulin from human articular cartilage
We have previously demonstrated that fibroblasts and invasive human breast carcinoma (HBC) cells specifically activate matrix metalloproteinase-2 (MMP-2) when cultured on 3-dimensional gels of type I collagen but not a range of other substrates. We show here the constitutive expression of membrane-type 1 (MT1)-MMP in both fibroblasts, and invasive HBC cell lines, that have fibroblastic attributes presumably acquired through an epithelial-to-mesenchymal transition (EMT). Treatment with collagen type I increased the steady-state MT1-MMP mRNA levels in these cells but did not induce either MT1-MMP expression or MMP-2 activation in noninvasive breast carcinoma cell lines, which retain epithelial features. Basal MT3-MMP mRNA expression had a pattern similar to that of MT1-MMP but was not up-regulated by collagen. MT4-MMP mRNA was seen in both invasive and noninvasive HBC cell lines and was also not collagen-regulated, and MT2-MMP mRNA was not detected in any of the HBC cell lines tested. These data support a role for MT1-MMP in the collagen-induced MMP-2-activation seen in these cells. In situ hybridization analysis of archival breast cancer specimens revealed a close parallel in expression of both collagen type I and MT1-MMP mRNA in peritumoral fibroblasts, which was correlated with aggressiveness of the lesion. Relatively high levels of expression of both mRNA species were seen in fibroblasts close to invasive tumor nests and, although only focally, in certain areas close to preinvasive tumors. These foci may represent hot spots for local degradation and invasive progression. Collectively, these results implicate MT1-MMP in collagen-stimulated MMP-2 activation and suggest that this mechanism may be employed in vivo by both tumor-associated fibroblasts and EMT-derived carcinoma cells to facilitate increased invasion and/or metastasis. 相似文献
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The human femoral head cartilage in 63 subjects with ages ranging from 16 to 100 years demonstrates that in the course of aging the cell density of the whole cartilage thickness decreases about 40 per cent. The reduction of the cellularity with age is more accentuated in the superficial than in the deeper zone and is even limited to the superficial zone during the latter part of aging. Proportionately the cell loss is similar in the superior and inferior poles of femoral head suggesting a uniform distribution of age related changes. In absolute value, the decrease of the superficial cell density is much higher in the inferior than in the superior pole; the decrease may be related to the propensity of this region to fibrillation. 相似文献
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The influence of age on the occurrence of phenotypic features of prognostic significance was studied in relation to the DNA index values, measured on DNA histograms from a series of 1019 breast cancer patients. Globally, the distributions of all parameters showed variations with age, the most prominent being the decreases in the percentage of estrogen receptor-negative and high proliferative activity cases with increasing age. When analyzed according to the DNA index classes, all parameters were found to some extent linked with the stage of genetic evolution. However, the associations varied with age, defining two extreme groups. The younger patients (less than 40 years) presented a more complete acquisition of the 'aggressive' phenotype and near-triploid tumors from this group were very frequently steroid hormone receptor-negative, high proliferation, and grade III. By contrast, near-triploid tumors in patients above 65 presented relatively frequently as receptor-positive, low proliferative activity, and even grade I. The correlation of the proliferative status with steroid hormone receptor content led to similar conclusions, high proliferation being more strongly correlated with the absence of estrogen and progesterone receptors in younger patients. Interestingly, the association between high proliferation and negative progesterone receptors was much weaker in patients above 55. Our results suggest that the currently established biological prognostic factors, including DNA profile, steroid hormone receptors, and histopathological grade, show patterns of association which vary with age. Of these, only progesterone receptor could be influenced by menopausal status. These findings have to be taken into consideration for future prognostic factor-related treatment decisions, but also for future methodological improvements of multivariate survival analyses. 相似文献
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PF Crookes BK Kaul TR DeMeester HJ Stein M Oka 《Canadian Metallurgical Quarterly》1993,128(4):411-415
The morphology of the arteries in the uterine wall was studied in three multiparous aged mares that had suffered repeated pregnancy failure. The uterine wall arteries exhibited elastosis of the intima or adventitia, or both, resembling "physiological pregnancy sclerosis". In areas affected by elastosis, degeneration of the pre-existing elastic fibres and increased glycosaminoglycans were frequently observed. Newly formed elastic fibres were not evident. Delayed resorption due to disordered metabolic turnover of the elastin was thought to be an important factor in the pathogenesis of the arterial elastosis in the uterine wall. 相似文献
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OBJECTIVES: This study quantified the impairment of quality of life attributable to body fatness by using the standardized SF-36 Health Survey. METHODS: Tertiles of waist circumference and body mass index (BMI) in 1885 men and 2156 women aged 20 to 59 years in the Netherlands in 1995 were compared. RESULTS: The odds ratios and 95% confidence intervals of subjects with the largest waist circumferences, compared with those in the lowest tertile, were 1.8 (1.3, 2.4) in men and 2.2 (1.7, 2.9) in women with difficulties in bending, kneeling, or stooping; 2.2 (1.4, 3.7) in men and 1.7 (1.2, 2.6) in women with difficulties in walking 500 m; and 1.3 (1.0, 1.9) in men and 1.5 (1.1, 1.9) in women with difficulties in lifting or carrying groceries. Anthropometric measures were less strongly associated with social functioning, role limitations due to physical or emotional problems, mental health, vitality, pain, or health change in 1 year. The relationship between quality of life measures and BMI were similar to those between quality of life measures and waist circumference. CONCLUSIONS: Large waist circumferences and high BMIs are more likely to be associated with impaired quality of life and disability affecting basic activities of daily living. 相似文献
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R Pawlicki 《Canadian Metallurgical Quarterly》1993,31(4):207-210
Light and transmission electron microscopy revealed in the elastic cartilage of the human epiglottis the presence of mast cells. Cytoplasmic granules of these cells contain characteristic cylindrical bodies, whose texture is different from that found in cytoplasmic granules of mast cells from other sites. The presence of mast cells in elastic cartilage, described for the first time, and the different substructure of their cytoplasmic granules, is considered as another proof of the heterogeneity of that cell type. 相似文献
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H Braunsberg 《Canadian Metallurgical Quarterly》1977,7(1):47-74
Work leading to the concept of hormone responsiveness of human breast cancer and current views of the mode of action of oestrogens in target tissues are reviewed. Results of oestrogen receptor assays are considered in relation to clinical response to tumours to endocrine therapy and difficulties encountered in the interpretation of receptor determinations are discussed. Recent work on the distribution of different forms of the oestrogen receptors in human tumours and their relation to clinical response may lead to better selection of patients for endocrine therapy. Results of receptor assays in male patients with breast cancer, in benign breast tumours and in malignant tumours at sites other than breast are reviewed, and work on receptors for hormones other than oestrogens is discussed briefly. Further work is needed on the integrity of the receptor mechanism in tumour cells and on the effects of hormone treatment. Methods for the separation and estimation of oestrogen receptors in human tumour tissue are reviewed and discussed. Errors arising during collection, storage and analysis are considered. Different ways of calculating and expressing results of these assays are mentioned. It is suggested that more accurate determinations of oestrogen receptors may lead to better discrimination between hormone responsive and unresponsive human breast tumours. 相似文献
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R Schneiderman N Rosenberg J Hiss P Lee F Liu RL Hintz A Maroudas 《Canadian Metallurgical Quarterly》1995,324(1):173-188
The concentration of free insulin-like growth Factor-I (IGF-I) and its complexes was determined in human normal and osteoarthritic synovial fluids, using ultrafiltration through 20- and 100-kDa membranes, followed by a radioimmunoassay of each fraction. In addition, freshly obtained samples of normal and osteoarthritic cartilage were incubated for several days, at both 4 and 37 degrees C. The incubation media (desorbates) were analyzed the same way as the synovial fluid samples to yield the concentration of IGF-I in cartilage in situ. Our findings are (i) Free IGF-I content is extremely low in both human serum and synovial fluid and there is no significant difference between the two; (ii) The concentration of total IGF-I in normal human synovial fluid is an order of magnitude lower than that in serum due mainly to the decrease in the concentration of the large complex; (iii) Preliminary results show that the total IGF-I in osteoarthritic synovial fluids is twice as high as in normal fluids; (iv) In normal human cartilage the levels of IGF-I in all its forms are very low and are consistent with the expected exclusion of large molecules by the extracellular matrix; (v) By contrast, in osteoarthritic cartilage, the concentrations of all forms of IGF-I are high, probably due to increased permeability of the matrix and binding; (vi) The levels of IGF-I found in normal human cartilage are more than an order of magnitude lower than those which stimulate proteoglycan synthesis in human cartilage in culture, while the IGF-I levels in osteoarthritic cartilage lie in the range in which stimulation does occur. 相似文献
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田湾金矿带流体成矿与金成色的关系研究 总被引:1,自引:0,他引:1
田湾成矿带的19个自然金样品的电子探针测试表明,该成矿带自然金的成色平均大于900%,成色很高;自然金中的杂质元素以Ag、Fe、Cu、Bi为主,这与该成矿带金主要赋存于黝铜矿、黄铁矿有关。该区金成色高的原因可能与成矿流体的沸腾不混溶作造成的突然降温降压从而导致金银的分离有关;黝铜矿形成过程对银的消耗造成金银的分离也是该区金成色高的原因之一。另外,该区Au/(Au+Ag)与Na^+/(Na^++K^ 相似文献