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991.
Cells have been grown in vitro in the presence of radioactive precursors; much of the glucosamine label is incorporated into the surface material, part of it is then spontaneously released into the medium, part is readily removed by an EDTA wash, and further amounts may be released by a mild trypsin treatment or by a period of chase.The material in the EDTA was from variously labelled cultures has been fractionated by Sephadex G-200 chromatography; the excluded peak has been analysed by Sepharose 6B and DEAE-cellulose chromatography and by electrophoresis on large pore polyacrylamide gels. Its sensitivity to pronase and hyaluronidase has been determined, as well as its sugar, lipids and amino acid composition.Cell-coat material from Polyoma and Rous sarcoma virus-transformed cell lines failed to show significant differences in chromatographic properties and in sugar and amino acid composition. Minor but reproducible differences were found in the polyacrylamide electrophoresis migration patterns, when comparing glucosamine-labelled materials. 相似文献
992.
Pasquale Chieco Maura Pagnoni Eleonora Romagnoli Cinzia Melchiorri 《The Histochemical journal》1993,25(8):569-577
Summary Mitotic index is a clinically important parameter in cancer pathology. We developed a staining method using Toluidine Blue
to detect efficiently and rapidly mitotic figures in sections of formalin-fixed paraffin-embedded human and rat tisues. Sections
were stained at acid pH with a 0.01% Toluidine Blue solution after removal of RNA with hydrochloric acid or ribonuclease.
The optimal pH of the TB staining solution was found to be 4.5 for rat tissues and 3.5 for human tissues. This procedure stained
mitotic figures much more intensely than other (extra)cellular structures. A quantitative estimate of the total number of
nuclei in the field where mitotic figures were counted, was obtained in an adjacent section hydrolysed in 5 N hydrochloric
acid and stained by the Feulgen reaction with a Schiff-type reagent containing 0.01% Toluidine Blue. This method specifically
stained interphase and mitotic nuclei and the field cellularity could be quantified by image cytometry. When these procedures
were performed on two consecutive serial sections, a mitotic index could be determined accurately by relating the count of
mitotic figures to the number of tumour cells. 相似文献
993.
994.
Nicoletta Rascio Paola Mariani Colombo Francesca Dalla Vecchia Pasquale Chitano 《Protoplasma》1985,126(1-2):153-157
Summary The entire vital cycle of chloroplasts was followed in spinach leaves, in order to determine the plastidial situations leading to the build-up of intrathylakoidal crystals. This kind of inclusion was noticed in the juvenile ontogenetic stages as well as in the senescent chloroplast stage, while intrathylakoidal crystals were not present in the mature organelles. The appearance of such crystals, which are known to consist of ribulose 1,5-diphosphate carboxylase, is interpreted as a consequence of an imbalance between enzyme level and membrane function.Supported by a C.N.R. grant. 相似文献
995.
Rats with skin-wounds surgically created on their backs were exposed immediately after surgery and every 12 h thereafter to pulsed, extremely-low-frequency magnetic fields. The shape of the pulse was a positive triangle (50 Hz, 8 mT peak). The rate of healing of skin wounds was evaluated macroscopically and by light and electron microscopy at 6, 12, 21, and 42 days after the operation. A significant increase in the rate of wound contraction was found in rats treated with magnetic fields. Forty-two days after surgery all treated animals show fully closed wounds, while control rats at the same time intervals still lacked a final 6% of the wound surface to be covered. Treated rats showed earlier cellular organization, collagen formation and maturation, and a very early appearance of newly formed vascular network. 相似文献
996.
Comparing patterns of geographic variation in cave crickets by combining geostatistic methods and Mantel tests 总被引:1,自引:0,他引:1
Donatella Cesaroni Pasquale Matarazzo Giuliana Allegrucci & Valerio Sbordoni 《Journal of Biogeography》1997,24(4):419-431
Geographic variation patterns of biological characters and environmental variables are compared by using a procedure employing multivariate analyses, production of contour maps by the kriging method with enclosed validation of estimates, and Mantel tests to assess the significance of comparisons. As biological material we chose a sample of Dolichopoda cave crickets populations from Central-Southern Italy. The kriging technique provides estimates of the interpolation error for each true and estimated point. This profitable feature offers the opportunity to use, with ascertained levels of confidence, the estimated z -scores for further analysis and to compare data collected within the same area, but not exactly coincident in location or number. In such a way, we were able to use for subsequent comparisons by means of Mantel tests the maximum number of data points for all data sets, which originally differed in sampling sites. The interpretation of the contour maps and their statistical comparison suggested that allozymes and epiphallus shape data sets follow the phylogenetic pathways within the Dolichopoda populations, whereas variation in leg elongation is almost entirely under the control of an environmental gradient, synthetically described by the cave temperature. 相似文献
997.
Ilaria Mucci Annalisa Legitimo Marta Compagnino Rita Consolini Pasquale Migliaccio Maria Rita Metelli Fabrizio Scatena 《Biologicals》2009,37(5):288-296
Dendritic cells (DCs) are effective as antigen-presenting cells in the immune system and are present at two functional stages depending on their maturation state. For experimental investigation of this concept, CD14+ monocytes from blood are isolated and cultured to generate in vitro the DCs needed for functional analysis. For positive selection of CD14+ monocytes we compared two immunomagnetic bead technologies: MACS® Separation, created by Miltenyi Biotec, and EasySep® Selection, created by StemCell Technologies. The monocytes provided dendritic cells for their functional analysis. Lipopolysaccharide was added to cultured DCs to induce maturation. Although both systems generated DCs from the positively selected CD14+ cells, there were certain differences between them. Morphological, phenotypic, and functional analysis showed that MACS®-selection provided DCs that have typical features corresponding to day 6 or 7 of maturation. EasySep®–DCs exist in a partially-mature state from day 6 onward, even without the addition of a maturation stimulus. The reason behind this partial maturation is possibly based on the dextran-coated beads that are associated with the EasySep® product. Both methods provide pure and viable DCs, but we would recommend using the MACS® system for obtaining DCs suitable for functional studies. 相似文献
998.
Daniela Montorio Gilda Cennamo Feliciana Menna Piero Donna Pasquale Napolitano Maria Angelica Breve Ugo Fiore Giovanni Cennamo Nicola Rosa 《Journal of biophotonics》2020,13(10)
The aim of this study is to evaluate corneal epithelial thickness (CET), corneal densitometry (CD) in 84 myopic eyes (57 patients) more than 22 years after photorefractive keratectomy, using anterior segment‐optical coherence tomography (AS‐OCT) and Scheimpflug imaging system. The CET was significantly higher in all operated eyes than in unoperated eyes in central sector. A statistically significant increase in CD in corneal anterior layer of central sector was shown in groups of operated eyes with greater ablation depth respect to unoperated eyes. While there was no significant difference in CD between the operated eyes groups with lower ablation depth and unoperated eyes. A significant trend toward higher values in anterior CD with deeper ablations in central sector was found. These noninvasive imaging techniques allow to better understand the corneal remodeling process after photoablation and to monitor the patients over time. 相似文献
999.
A.M. D'Onghia F. de Pasquale F. Carimi V. Savino F.G. Crescimanno 《Journal of Phytopathology》1997,145(2-3):77-79
Somatic embryos were obtained from stylar tissues of three lemon plants, one of cv Lunario, one of Femminello Zagara Bianca, and one of Femminello Santa Teresa. These plants, as shown by visual observations and indexing on woody indicators, were affected by exocortis and two or more virus-like diseases such as psorosis, concave gum, impietratura and cristacortis. Two of the sources contained also mechanically transmissible viruses. Twelve 18-month-old plantlets originating from style culture-derived somatic embryos, four from each source, consistently gave negative reactions when assayed by grafting, mechanical inoculation, and serologically for the presence of viruses, virus-like agents and viroids. It was concluded that, similar to other woody species (e.g. grapevine), somatic embryogenesis opens new possibilities for the sanitary improvement of Citrus. 相似文献
1000.