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991.
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
992.
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
993.
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
994.
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
995.
996.
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
997.
Aim Optimal body size theories predict that large clades have a single, optimal, body size that serves as an evolutionary attractor, with the full body size spectrum of a clade resulting from interspecific competition. Because interspecific competition is believed to be reduced on islands, such theories predict that insular animals should be closer to the optimal size than mainland animals. We test the resulting prediction that insular clade members should therefore have narrower body size ranges than their mainland relatives. Location World‐wide. Methods We used body sizes and a phylogenetic tree of 4004 mammal species, including more than 200 species that went extinct since the last ice age. We tested, in a phylogenetically explicit framework, whether insular taxa converge on an optimal size and whether insular clades have narrow size ranges. Results We found no support for any of the predictions of the optimal size theory. No specific size serves as an evolutionary attractor. We did find consistent evidence that large (> 10 kg) mammals grow smaller on islands. Smaller species, however, show no consistent tendency to either dwarf or grow larger on islands. Size ranges of insular taxa are not narrower than expected by chance given the number of species in their clades, nor are they narrower than the size ranges of their mainland sister clades – despite insular clade members showing strong phylogenetic clustering. Main conclusions The concept of a single optimal body size is not supported by the data that were thought most likely to show it. We reject the notion that inclusive clades evolve towards a body‐plan‐specific optimum. 相似文献
998.
Ilaria De Pasquale Maria Calasso Leonardo Mancini Danilo Ercolini Antonietta La Storia Maria De Angelis Raffaella Di Cagno Marco Gobbetti 《Applied and environmental microbiology》2014,80(14):4085-4094
Pyrosequencing of the 16S rRNA gene, community-level physiological profiles determined by the use of Biolog EcoPlates, and proteolysis analyses were used to characterize Canestrato Pugliese Protected Designation of Origin (PDO) cheese. The number of presumptive mesophilic lactococci in raw ewes'' milk was higher than that of presumptive mesophilic lactobacilli. The numbers of these microbial groups increased during ripening, showing temporal and numerical differences. Urea-PAGE showed limited primary proteolysis, whereas the analysis of the pH 4.6-soluble fraction of the cheese revealed that secondary proteolysis increased mainly from 45 to 75 days of ripening. This agreed with the concentration of free amino acids. Raw ewes'' milk was contaminated by several bacterial phyla: Proteobacteria (68%; mainly Pseudomonas), Firmicutes (30%; mainly Carnobacterium and Lactococcus), Bacteroidetes (0.05%), and Actinobacteria (0.02%). Almost the same microbial composition persisted in the curd after molding. From day 1 of ripening onwards, the phylum Firmicutes dominated. Lactococcus dominated throughout ripening, and most of the Lactobacillus species appeared only at 7 or 15 days. At 90 days, Lactococcus (87.2%), Lactobacillus (4.8%; mainly Lactobacillus plantarum and Lactobacillus sakei), and Leuconostoc (3.9%) dominated. The relative utilization of carbon sources by the bacterial community reflected the succession. This study identified strategic phases that characterized the manufacture and ripening of Canestrato Pugliese cheese and established a causal relationship between mesophilic lactobacilli and proteolysis. 相似文献
999.
1000.
Irradiation of Mesenchymal Stromal Cells With Low and High Doses of Alpha Particles Induces Senescence and/or Apoptosis
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