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1.
Needle biopsy of the liver is of great value in appreciating the intensity, type and topography of the steatosis commonly observed during chronic alcoholic diseases. The usual semiquantitative optical analysis is very inaccurate and depends on the subjectivity and training of the pathologist. We therefore performed an automated analysis of liver steatosis using a QTM 720 image analyzer connected to a PDP 11/34 minicomputer. Visual control of the results of the automated analysis showed it to give good results: 94% of the droplets were detected and only 10% of the patterns automatically selected were not droplets. Eight normal biopsies and 37 biopsies showing alcoholic liver steatosis were analyzed. The automated morphometric analysis calculated the mean density (percentage) of steatosis and the size distribution of the droplets. Statistical comparison of these results with those of the semiquantitative optical analysis performed independently by two pathologists showed a significant correlation between their calculations of the density/degree of steatosis but significant differences for their evaluation of the type of steatosis. The pathologists constantly overestimated the ratio of macrodroplets to microdroplets.  相似文献   

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Background  

Fatigue is a crucial sensation that triggers rest, yet its underlying neuronal mechanisms remain unclear. Intense long-term fatigue is a symptom of chronic fatigue syndrome, which is used as a model to study the mechanisms underlying fatigue.  相似文献   

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Electron microscopic and cytophotometric studies of low-grade malignant cutaneous lymphomas and non-malignant skin diseases revealed substantial differences between these groups of diseases. In the latter case, the DNA content per nucleus is diploid but in the former an atypical distribution of DNA content per nucleus (more than 5% aneuploid and polyploid nuclei) is observed in addition to a significant excess of the mean DNA content per nucleus above the diploid standard level. In lymphomas electron microscopy reveals clusters of atypical lymphoid cells with irregularly shaped nuclei, nuclear pockets, nuclear extrusions, network of cytoplasmic microfilaments. These features never occur with skin diseases. The data obtained can be helpful in the diagnostics of the low-grade malignant cutaneous lymphomas.  相似文献   

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The ultrastructure of the sinusoidal endothelial and Kupffer cells of mouse liver has been studied under the normal physiological conditions according to the morphometric method. The similarity of quantitative characteristics of some subcellular structure of these cells has been determined. Essential differences between endothelial and Kupffer cells were revealed that well compare with the results of the investigation of their endocytous ability.  相似文献   

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Mucopolysaccharides were obtained and fractionated from the skin of two eleasmobranch fishes, the Blue shark and Sandbar shark. In both species, the main polysaccharide fractions were hyaluronic acid, and chondroitin sulfate B. The total mucopolysaccharide content, however, varied considerably. In both species, the chondroitin sulfate B fractions were oversulfated. In both species, keratosulfate appeared to be present in small amounts.  相似文献   

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This study has attempted to research, in detail, the dimensions and form of the malleus, and to indicate possible differences with regard to race, sex and side of origin (left or right). The ossicles were obtained from 75 adult cadavers and the dimensions were determined with the aid of a reflection microscope. Clear statistically significant differences were found between the Negroid and Caucasoid races, as well as between the right and left ossicles. No meaningful differences were determined between male and female ossicles.  相似文献   

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A comparative morphometric study of lip epithelia in cattle, rats, and humans was undertaken using stereological techniques. Vermilion border and skin specimens of cattle, rats and humans were processed under standardized conditions for light microscopic observation. Stereological techniques were employed to obtain volumetric densities of each epithelial layer. The results obtained show that although the absolute volume of each epithelial stratum of the vermilion border and of the skin varies markedly in the different species studied, the relative volume of these strata in relation to the entire epithelium is similar in all epithelia.  相似文献   

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Studies were carried out to detect the modifications, if any, on the peri-umbilical flora of six healthy volunteers after two or three daily applications of Hexomedine solution (HEX) and Betadine solution (PVI) repeated for five consecutive days. A standardized scrubbing method was used for bacterial sampling. Surviving bacteria were selected with both selective and non-selective media, and then identified by gas chromatographic fatty acid analysis. Both antiseptics were highly effective, showing both immediate and residual antimicrobial activities. The use of HEX led to a slight increase in Gram-positive cocci and a small decrease in coryneforms, but PVI produced a marked increase in Gram-positive cocci and a sharp decrease in coryneforms. The two antiseptics, however, caused no major alteration in the cutaneous microbial population. Indeed, neither the overgrowth of Gram-negative bacilli nor the emergence of resistant species was observed.  相似文献   

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The authors describe two measuring and counting method suitable for the morphometric and histometric analysis of the main structures of the kidneys: the volume of the cortical substance and medulla, the pelvis and vessels; the quantity, the size and the volume of glomeruli.  相似文献   

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Studies were carried out to detect the modifications, if any, on the peri-umbilical flora of six healthy volunteers after two or three daily applications of Hexomedine solution (HEX) and Betadine solution (PVI) repeated for five consecutive days. A standardized scrubbing method was used for bacterial sampling. Surviving bacteria were selected with both selective and non-selective media, and then identified by gas chromatographic fatty acid analysis. Both antiseptics were highly effective, showing both immediate and residual antimicrobial activities. The use of HEX led to a slight increase in Gram-positive cocci and a small decrease in coryneforms, but PVI produced a marked increase in Gram-positive cocci and a sharp decrease in coryneforms. The two antiseptics, however, caused no major alteration in the cutaneous microbial population. Indeed, neither the overgrowth of Gram-negative bacilli nor the emergence of resistant species was observed.  相似文献   

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The epiphyseal cartilage and diaphysis of the tibia have been studied at dehydration and burn trauma. Dehydration produces certain disturbances in growth and formation of the bone, and burn trauma--development of dystrophic changes.  相似文献   

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Primary adenocarcinoma of the vagina accounts for approximately 1% of all invasive carcinomas of the female genital tract. This paper reports on a study of four cases of primary adenocarcinoma (including one with in utero diethylstilbestrol exposure) of the vagina from the files of the Medical University of South Carolina. Both tissue sections and cytologic preparations from each case were evaluated in order to delineate the morphologic characteristics of the cells that compose the lesions. Histologically, the lesions primarily presented the tubular cystic pattern; solid and papillary growth patterns were also seen in one case. The constituent cells included clear cells, hobnail cells and secretory and nonsecretory tubular cystic cells. All specimens were examined for the following parameters: cell population, nuclear area, cytoplasmic area, nuclear/cytoplasmic (N/C) proportions, nuclear and cytoplasmic characteristics. While a fairly detailed profile of the morphologic criteria for hobnail cells was developed, the cellular profiles of the other malignant glandular cells originating in primary vaginal adenocarcinoma remain less certain.  相似文献   

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Muscle weakness and effort intolerance are common in maintenance hemodialysis (MHD) patients. This study characterized morphometric, histochemical, and biochemical properties of limb muscle in MHD patients compared with controls (CTL) with similar age, gender, and ethnicity. Vastus lateralis muscle biopsies were obtained from 60 MHD patients, 1 day after dialysis, and from 21 CTL. Muscle fiber types and capillaries were identified immunohistochemically. Individual muscle fiber cross-sectional areas (CSA) were quantified. Individual fiber oxidative capacities were determined (microdensitometric assay) to measure succinate dehydrogenase (SDH) activity. Mean CSAs of type I, IIA, and IIX fibers were 33, 26, and 28% larger in MHD patients compared with CTL. SDH activities for type I, IIA, and IIX fibers were reduced by 29, 40, and 47%, respectively, in MHD. Capillary to fiber ratio was increased by 11% in MHD. The number of capillaries surrounding individual fiber types were also increased (type I: 9%; IIA: 10%; IIX: 23%) in MHD patients. However, capillary density (capillaries per unit muscle fiber area) was reduced by 34% in MHD patients, compared with CTL. Ultrastuctural analysis revealed swollen mitochondria with dense matrix in MHD patients. These results highlight impaired oxidative capacity and capillarity in MHD patients. This would be expected to impair energy production as well as substrate and oxygen delivery and exchange and contribute to exercise intolerance. The enlarged CSA of muscle fibers may, in part, be accounted for by edema. We speculate that these changes contribute to reduce limb strength in MHD patients by reducing specific force.  相似文献   

18.
A foliar morphometric approach to the study of salicaceae   总被引:1,自引:0,他引:1  
An assemblage of leaves of four species of willows (Salix viminalis, S. alba, S. fragilis, andS. caprea), two of their hybrids (S. alba ×fragilis andS. caprea ×viminalis), two species of poplars (Populus alba andP. tremula), and two “external” species (Elaeagnus angustifolia andPyrus salicifolia) was analyzed. The study was designed to determine whether leaves that are very close in shape but belong to different species, particularly the elongated leaves ofS. viminalis, S. alba, S. fragilis, E. angustifolia, andP. salicifolia, could be discriminated by continuous foliar characters (that is, vegetative characters), despite both the great foliar polymorphism met in Salicaceae (especially in the genusPopulus) and hybridization problems. Our results show that multivariate analyses (principal component analysis [PCA] and cluster analysis) of an appropriate character set enable leaves to be classified in their own species at more than 98 %, even in these difficult conditions. It can be seen from this work that PCA is a good tool when it keeps a maximum of total variability; that is, when there are few taxa; on the other hand, cluster analysis is more appropriate with many taxa. One can then envisage the application of this morphometric approach to fossil-imprint determination, in which even fragmentary paleobotanical remains could be included. This would give access to real biodiversity of tertiary flora and to intraspecific variability.
Résumé  Un assemblage de feuilles de quatre espèces de saules (Salix viminalis, S. alba, S. fragilis, etS. caprea), deux de leurs hybrides (S. alba ×fragilis etS. caprea ×viminalis), ainsi que deux espèces de peupliers (Populus alba etP. tremula), et deux espèces “externes” (Elaeagnus angustifolia etPyrus salicifolia) a été étudié. Le but était de savoir si des feuilles de forme très proche mais d’espèces différentes (en particulier les feuilles allongées deS. viminalis, S. alba, S. fragilis, E. angustifolia, etP. salicifolia) pouvaient être discriminées par des caractères foliaires (donc végétatifs) continus, et ce malgré le très grand polymorphisme foliaire existant chez les Salicacées (surtout chez le genrePopulus), et les problèmes d’hybridation. Il en a résulté que les analyses multivariées (ACP et analyse agrégative) associées à un jeu de caractères approprié, permettent à plus de 98% le classement des feuilles dans leur propre espèce, même dans ces conditions difficiles. Il ressort de ce travail que l’ACP n’est un bon outil que lorsqu’ elle conserve un maximum de la variabilité totale, c’est-à-dire ici, quand les taxa sont peu nombreux; en revanche, l’analyse agrégative exprime le maximum de ses capacités en présence d’un grand nombre de taxa. On peut alors envisager l’application de cette approche morphométrique à la détermination d’empreintes fossiles, dans le but d’inclure même les restes fragmentaires dans les études paléobotaniques, ce qui donnerait accès à la réelle biodiversité des flores tertiaires et à la variabilité existant au sein des espèces.
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Proceeding from the correlation of x-ray, endoscopic and morphological (morphometric) findings the authors defined significant x-ray symptoms (including enlarged lymphoid follicles of various sizes) of chronic nonulcerative colitis.  相似文献   

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