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Summary Interspecific heritability values were estimated using parent-offspring regression analyses for 11 morphological traits differentiating Clarkia nitens and C. speciosa subsp. polyantha. Estimates ranged from near 0 for anther color and germination percentage, to 0.8 for calyx length and petal tip color. Phenotypic, genetic, and environmental correlation matrices were computed to determine the extent of interspecific correlations of traits. Cluster analyses of the genetic and environmental correlation matrices each resulted in three clusters of correlated traits; however, the clusters derived from the two matrices were different. The clusters produced by analysis of the environmental correlation matrix were similar to the factors obtained from principal component analysis of the phenotypic correlation matrix. Genetic correlations may result from strong linkage due to interspecific chromosomal differences.  相似文献   

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Dynamics of structural restoration of the peripheral nerve (n. ischiadicus) have been studied in the noninbred rats in 3 series of experiments: after local freezing, pinching and cutting with a subsequent connection of the nerve ends by means of an implanted arterial vessel. As demonstrate the methods of light and electron microscopy, myelinization of the nervous fibers in the distal part of the nerve begins between the 10th-20th days after the effect. Further, amount of the myelinated nerve fibers (NF) significantly increases, they become essentially thicker. However, even in the later time of the observation (9 months) most of NF remain thinner than in the control nerve; this demonstrates that the reparative processes take a longer time than it was supposed before. The comparative analysis makes it possible to recommend the cryogenic lesion of the nerve as the most perspective model to study processes of the reparative histogenesis. Certain positive signs of sutureless connection of the cut nerve by means of the implanted arterial vessel are noted for clinical substitution of vast diastases of the nerve.  相似文献   

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Aim:  To investigate the effect of native, heated and glycated bovine serum albumin (BSA) on the ulcerative colitis (UC) and non-UC colonic microbiota in vitro .
Methods and Results:  Continuous flow culture (CFC) models of the human colonic microbiota inoculated with faeces from UC and non-UC volunteers were maintained on BSA as growth substrate. Changes in bacterial populations and short-chain fatty acids were determined. UC and non-UC microbiota differed significantly in microbial populations, with elevated numbers of sulfate-reducing bacteria (SRB) and clostridia in the microbiota from UC patients. Compared with native BSA, glycated BSA modulated the gut microbiota of UC patients in vitro towards a more detrimental community structure with significant increases in putatively harmful bacteria (clostridia, bacteroides and SRB; P  < 0·009) and decreases in dominant and putatively beneficial bacterial groups (eubacteria and bifidobacteria; P  < 0·0004). The levels of beneficial short-chain fatty acids were significantly decreased by heated or glycated BSA, but were increased significantly by native BSA.
Conclusion:  The UC colonic microbiota maintained in CFC was significantly modified by glycated BSA.
Significance and Impact of the Study:  Results suggest that dietary glycated protein may impact upon the composition and activity of the colonic microbiota, an important environmental variable in UC.  相似文献   

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Human plasma low density lipoprotein (LDL) that had been rendered polycationic by coupling with N, N-dimethyl-1, 3-propanediamine (DMPA) was shown by electron microscopy to bind in clusters to the surface of human fibroblasts. The clusters resembled those formed by polycationic ferritin (DMPA-feritin), a visual probe that binds to anionic site on the plasma membrane. Biochemical studies with (125)I-labeled DMPA-LDL showed that the membrane-bound lipoprotein was internalized and hydrolyzed in lysosomes. The turnover time for cell bound (125)I-DMPA-LDL, i.e., the time in which the amount of (125)I-DMPA-LDL degraded was equal to the steady-state cellular content of the lipoprotein, was about 50 h. Because the DMPA-LDL gained access to fibroblasts by binding nonspecifically to anionic sites on the cell surface rather than by binding to the physiologic LDL receptor, its uptake failed to be regulated under conditions in which the uptake of native LDL was reduced by feedback suppression of the LDL receptor. As a result, unlike the case with native LDL, the DMPA-LDL accumulated progressively within the cell, and this led to a massive increase in the cellular content of both free and esterified cholesterol. Studies with (14)C-oleate showed that at least 20 percent of the accumulated cholesteryl esters represented cholesterol that had been esterified within the cell. After 4 days of incubation with 10 μg/ml of DMPA-LDL, fibroblasts had accumulated so much cholesteryl ester that neutral lipid droplets were visible at the light microscope level with Oil Red O staining. By electron microscopy, these intracellular lipid droplets were observed to lack a tripartite limiting membrane. The ability to cause the overaccumulation of cholesteryl esters within cells by using DMPA-LDL provides a model system for study of the pathologic consequences at the cellular level of massive deposition of cholesteryl ester.  相似文献   

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Crohn's disease is a chronic disease characterized by oxidant-induced tissue injury and increased intestinal permeability. A consequence of oxidative damage is the accumulation of DNA strand breaks and activation of poly(ADP-ribose) polymerase (PARP), which subsequently catalyzes ADP-ribosylation of target proteins. In this study, we assessed the role of PARP in the colitis seen in interleukin (IL)-10 gene-deficient mice. IL-10 gene-deficient mice demonstrated significant alterations in colonic cellular energy status in conjunction with increased permeability, proinflammatory cytokine release, and nitrosative stress. After 14 days of treatment with the PARP inhibitor 3-aminobenzamide, IL-10 gene-deficient mice demonstrated normalized colonic permeability; reduced tumor necrosis factor-alpha and interferon-gamma secretion, inducible nitric oxide synthase expression, and nitrotyrosine levels; and significantly attenuated inflammation. Time course studies demonstrated that 3-aminobenzamide rapidly altered cellular metabolic activity and decreased cellular lactate levels. This was associated with normalization of colonic permeability and followed by a downregulation of proinflammatory cytokine release. Our data demonstrate that inhibition of PARP activity results in a marked improvement of colonic inflammatory disease and a normalization of cellular metabolic function and intestinal permeability.  相似文献   

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Allozymic and morphometric variation was studied in 28 clones ofLemna minor. This variation was compared with the corresponding variation in four clones ofLemna gibba and four clones ofSpirodela polyrrhiza. A high level of allozymic variation was observed among the clones, despite having been grown under uniform laboratory conditions for several years and despite its quasi-exclusive clonal means of propagation. Based on degree of allozymic similarity,Spirodela polyrrhiza was distinguished from the twoLemna species but the latter species were genetically indistinguishable. Allozymic similarity among clones ofLemna minor was not related to morphometric similarity, nor was it related to the degree of geographic separation or climatic similarity of their sites of origin. The results suggest that allozymic variation among these clones ofLemna minor may be largely neutral and not a consequence of differential selection.  相似文献   

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The present study was undertaken to check whether there is a correlation between the clinical stage and the ultrastructural morphometric picture of leukaemic cells. The investigations concerned 12 cases of chronic lymphocytic leukaemia. Qualitative morphological differences could not be detected between cells originating from various clinical groups. Morphometric ultrastructural analysis, however, revealed differences in the volume fraction of cytoplasmic cell components, not only between clinical groups, but also within them. None of the clinical groups were homogeneous, but the cases classified to groups 0, I and II were uniform as regards the volume fractions of the nucleus and some cytoplasmic components. Ultrastructural morphometric studies seem to suggest that counterparts to the clinical state may be found in the morphology of leukaemic cells.  相似文献   

10.
Some characteristics of the mitochondria of hepatocytes and of three hepatoma cell lines have been compared. By means of stereologic analysis of electron micrographs of cross-sections through cells the volume of mitochondria per unit volume of cell cytoplasm and the surface areas of the mitochondrial envelope and cristae membranes have been measured. The relative mitochondrial volume in the cytoplasm decreases with increasing growth rate but the surface area of outer and cristae membranes per unit volume of mitochondria is not altered. The internal organization of hepatoma mitochondria, however, differs distinctly from that of normal liver mitochondria as evident from electron micrographs; the hepatoma cells contain mitochondria in which parallel cristae appear to cross the whole mitochondrial profile unlike the irregular, short cristae seen in normal liver mitochondria. Furthermore, in the fast-growing hepatoma cells the mitochondrial matrix appears less dense than in the hepatocyte. Hepatoma cells contain less organized rough endoplasmic reticulum than normal liver cells and the spatial relationship of the mitochondria to the rough cisternae, seen in the hepatocyte, is absent in the fast-growing hepatoma cell lines. It is concluded that hepatoma cells have fewer mitochondria than normal liver cells, but that the organelles have a normal content of inner membranes.  相似文献   

11.
The paper is concerned with comparative assessment of the diagnostic potentialities of the x-ray, endoscopic and pathomorphological methods of investigation. The results of the examination of 100 patients operated upon for nonspecific ulcerative colitis (54) and Crohn's disease (46) were analyzed. The advantages of these methods were demonstrated. A conclusion was made of the necessity of the use of the above methods for specified diagnosis of nonspecific colitis.  相似文献   

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During a period of ten years, 109 colorectal cytology specimens were obtained from 41 patients with chronic ulcerative colitis. There were 28 male and 13 female patients, whose average age was 45 years. All patients were symptomatic and had ulcerative colitis with repeated attacks of profuse diarrhea on the average for 12 years prior to their first cytologic examination. Eight cytology specimens were positive for malignant cells, 35 had atypia, 58 were negative and 8 were unsatisfactory. The malignant cells showed marked anisocytosis, pleomorphism and nuclear hyperchromasia and appeared in loosely cohesive clusters or in single forms in an inflammatory and necrotic background. Subsequent colectomy revealed invasive carcinoma in five patients and carcinoma in situ in two. Smears that were negative or showed atypia contained abundant chronic inflammatory cells. The atypical colonic epithelial cells contained prominent nuclei and formed cohesive clusters. Surgical biopsy and/or segmental resection revealed the presence of polyps, pseudopolyps, polypoid hyperplasia, mucosal atypia and crypt abscesses in patients with atypical and negative cytologic findings. It is concluded that cytologic examination of the colon can play an important role in the examination of patients with ulcerative colitis and allows for the detection of malignant transformation of the colonic mucosa.  相似文献   

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The authors presented a clinicoroentgenological picture of bronchioloalveolar cancer based on the analysis of 154 cases; 4 types of disease were defined: peripheral tumors, pseudopneumonic type tumors, multiple nodular formations, and mixed type tumors. Common features of this disease and symptomatology of each separate type were described. The most prominent features of bronchioloalveolar cancer are the absence of bronchial tree involvement and frequent presence of typical cavities with well defined outlines and "lattice" structure. The characteristic features of peripheral bronchioloalveolar cancer are slow growth rates, subpleural localization, inhomogeneous structure, and irregular outlines. The mixed type (far advanced tumors) is characterized by the combination of lobular, spheroidal and microfocal changes. Early recognition of definite types of bronchioloalveolar cancer ensures timely surgical treatment and prevents disease progression to disseminated bilateral lesions.  相似文献   

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Investigation of correlations between a number of two-state attributes for a sample of grass genera revealed that a high proportion of the correlations were statistically significant. There were proportionately more correlations between attributes from the same organ than between attributes from different organS. Furthermore, attributes associated with the fruit and leaf were found to be more closely correlated with attributes other than those of the flower and spikelet, thereby indicating fruit and leaf attributes to be important in the classification of the grasseS. It is considered that the correlations have arisen in part as a result of the phylogenetic origins of the genera and in part as a response to natural selection determining distribution of genera adapted to present-day habitats.  相似文献   

17.
Two hundred and fifty-eight angiograms have been analysed, 78 of them are from persons without any renal and cardio-vascular pathology, 184--from patients with vasorenal hypertension. Total area of transversal sections of the arteries is stated (characterizing the arterial bed capacity of the kidney) and its relation to the transversal section area of the renal projection (arterio-renal index). These parameters decrease with age, and are especially noticeable when vasorenal hypertension is present. Stenosis of renal arteries (up to 30%) of various etiology do not practically change the capacity of the renal arterial bed, and when the degree of stenosis increases up to 80%, an essential decrease both in the arterial bed capacity and in the arterio-renal index takes place.  相似文献   

18.
Patterns of genetic and morphometric differentiation were surveyed in Melitaea (Mellicta) athalia populations of the Carpathian Basin. This species has a wide distribution and exists under a wide variety of ecological conditions. It has two ecotypes in Hungary: with either one or two broods per year. It is of particular interest to reveal the main factors driving differentiation patterns in this species. Samples in our study were obtained from five Hungarian and one Transylvanian (Romanian) regions. Enzyme polymorphism, wing characters and male external genitalia were analysed using traditional morphometric methods. Statistical methods were optimized to compare morphological and genetic data. The results of genetic surveys revealed a clear regional pattern of differentiation in M. athalia. Moreover, the results of principal component analysis, Bayesian clustering and the dendrogram all suggested that the regions can be classified into two groups corresponding to the East or West zones of the Carpathian Basin. In contrast, differentiation between the two ecotypes was less expressed in the genetic variation of M. athalia. Results of the analyses conducted on phenotypic variation also suggested a regional pattern for both sets of morphometric characters (wings and external genitalia). At the same time, neither East–West regional division nor ecotype differentiation was detected in the morphometric studies. In sum, our analyses confirmed that both genetic and phenotypic variations of M. athalia exhibit a regional pattern rather than the differentiation between the two ecotypes. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ?? , ??–??.  相似文献   

19.
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   

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The morphometry and sculpture pattern of Serpocaulon spores was studied in a phylogenetic context. The species studied were those used in a published phylogenetic analysis based on chloroplast DNA regions. Four additional Polypodiaceae species were examined for comparative purposes. We used scanning electron microscopy to image 580 specimens of spores from 29 species of the 48 recognised taxa. Four discrete and ten continuous characters were scored for each species and optimised on to the previously published molecular tree. Canonical correspondence analysis (CCA) showed that verrucae width/verrucae length and verrucae width/spore length index and outline were the most important morphological characters. The first two axes explain, respectively, 56.3% and 20.5% of the total variance. Regular depressed and irregular prominent verrucae were present in derived species. However, the morphology does not support any molecular clades. According to our analyses, the evolutionary pathway of the ornamentation of the spores is represented by depressed irregularly verrucae to folded perispore to depressed regular verrucae to irregularly prominent verrucae.  相似文献   

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