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401.
Tredicucci A 《Science (New York, N.Y.)》2003,302(5649):1346-1347
402.
The hippocampus has differentiated into an extensively connected recurrent stage (CA3) followed by a feed-forward stage (CA1). We examined the function of this structural differentiation by determining how cell ensembles in rat CA3 and CA1 generate representations of rooms with common spatial elements. In CA3, distinct subsets of pyramidal cells were activated in each room, regardless of the similarity of the testing enclosure. In CA1, the activated populations overlapped, and the overlap increased in similar enclosures. After exposure to a novel room, ensemble activity developed slower in CA3 than CA1, suggesting that the representations emerged independently. 相似文献
403.
Bone mineral content of the third metacarpal bone in Quarter Horse foals from birth to one year of age 总被引:1,自引:0,他引:1
Peter Reichmann MD Alessandro Moure MSc Humberto Remigio Gamba MD 《Journal of Equine Veterinary Science》2004,24(9):391-396
Dual photon absorptiometry (DPA) is a valid method for bone mineral content (BMC) evaluation, but there are no reports on the use of this technology in in vivo studies in the horse. The aim of the current study was to evaluate the changes of BMC of the third metacarpal bone (MC3) in vivo in foals during their first year of life using DPA. The BMC of the MC3 of 41 Quarter Horse foals was evaluated every 4 weeks during their first year of life by DPA using a bienergetic Gadolinium-153 (153Gd) source. To the authors' knowledge, this is the first report of an in vivo study of BMC in foals using DPA by means of a bienergetic 153Gd source. The results demonstrated a positive correlation of age, heart girth, and withers height with BMC of the MC3 independent of gender and an exponential behavior of the BMC increment along the first year of life. There was an effect of weaning associated with change in diet and stall confinement on BMC in foals weaned at age 17 weeks, but not in foals weaned at age between 19 and 24 weeks. 相似文献
404.
Oliveira AL Costa C Rodella RA Silva BF Amarante AF 《Tropical animal health and production》2009,41(5):775-782
The influence of trichomes on vertical migration and survival of Haemonchus contortus infective larvae (L3) on different forages was investigated. Four different forages showing different distributions of trichomes
(Brachiaria brizantha cv. Marandu, Brachiaria brizantha cv. Xaraes, Andropogon gayanus, and Stylosanthes spp.), and one forage species without trichomes (Panicum maximum cv. Tanzania), were used. Forages cut at the post-grazing height were contaminated with faeces containing L3. Samples of
different grass strata (0–10, 10–20, >20 cm) and faeces were collected for L3 quantification once per week over four weeks.
In all forages studied, the highest L3 recovery occurred seven days after contamination, with the lowest recovery on A. gayanus. In general, larvae were found on all forages’ strata. However, most of the larvae were at the lower stratum. There was no
influence of trichomes on migration and survival of H. contortus L3 on the forages. 相似文献
405.
This study was performed to ascertain whether a standardized extract from Echinacea angustifolia (Polinacea™) affects proliferation and interferon gamma (IFN-γ) secretion in bovine peripheral blood mononuclear cells (PBMC).PBMC from six Holstein heifers were incubated with 0, 6.3, 20, 60, or 180 μg/ml of the tested compound. Proliferation was stimulated by concanavalin A (ConA) or pokeweed-mitogen (PWM). Secretion of IFN-γ was stimulated by ConA.All concentrations of Polinacea™ exerted a mitogenic effect. With respect to control PBMC (0 μg/ml), the lowest and highest increase of proliferation were observed with Polinacea™ at 6.3 (2-fold increase) or 180 (10-fold increase) μg/ml, respectively. Polinacea™ at 180 μg/ml reduced ConA-driven proliferation, whereas at 20 and 60 μg/ml improved proliferation of PWM-stimulated PBMC. IFN-γ secretion was not affected. In conclusion, Polinacea™ modulates bovine PBMC proliferation, and deserves to be tested in vivo to define conditions that may benefit from its utilization. 相似文献
406.
Bussadori C Pradelli D Borgarelli M Chiavegato D D'Agnolo G Menegazzo L Migliorini F Santilli R Zani A Quintavalla C 《Veterinary journal (London, England : 1997)》2009,182(2):187-192
This prospective study was conducted to evaluate the prevalence and severity of ocular lesions in dogs with anemia (packed cell volume 20%) and/or thrombocytopenia (platelet count < 150,000/μL). Dogs were divided into four groups: (1) anemic (n = 17); (2) thrombocytopenic (n = 36); (3) anemic and thrombocytopenic (n = 24); and (4) healthy controls (n = 26). The prevalence of ophthalmic lesions in these four groups was 12%, 42%, 42% and 0%, respectively. Anemia was not associated with the presence of ocular lesions (P = 0.41) or their severity. Thrombocytopenia was significantly associated with the presence of ocular lesions (P = 0.0016) and with their severity (P = 0.017). We conclude that thrombocytopenia, but not anemia, is associated with ocular lesions in dogs. 相似文献
407.
Papetti A Pruzzo C Daglia M Grisoli P Bacciaglia A Repetto B Dacarro C Gazzani G 《Journal of agricultural and food chemistry》2007,55(2):278-284
Some beverages and foods protect tooth surfaces against Streptococcus mutans colonization. Adhesion of S. mutans is a crucial step in the initiation and development of dental caries. In this study, we showed that barley coffee (BC), a beverage made from roasted barley, interferes with S. mutans adsorption to hydroxyapatite (HA), and we identified its antiadhesive components. The effects of sublethal concentrations (sub-MICs) of BC on the adhesion of S. mutans to saliva-coated HA beads were assessed using three experimental approaches: (A) Beads were pretreated with BC before adding bacteria, (B) BC and bacteria were added to the beads simultaneously, and (C) streptococci grown in the presence of sub-MICs of BC were added to the beads. All treatments induced variable but significant inhibition of S. mutans sucrose-dependent and -independent adherence to HA. Similar results were obtained with other oral streptococci. BC components were fractioned by dialysis and gel filtration chromatography; the <1000 Da molecular mass (MM) fraction, which contains polyphenols, zinc, and fluoride ions, and the >1000 kDa MM fraction, which consists of a potent brown antioxidant, melanoidin, both displayed antiadhesive properties. High-MM melanoidin was not detected in unroasted barley, indicating that it forms during the roasting process. Results suggest that BC consumption may influence the colonization of tooth surfaces by cariogenic bacteria. 相似文献
408.
Paolo Guidetti Piero Addis Fabrizio Atzori Simona Bussotti Antonio Cal Alessandro Cau Jean‐Michel Culioli Giuseppe De Lucia Antonio Di Franco Manfredi Di Lorenzo Maria Cristina Follesa Vittorio Gazale Giorgio Massaro Francesco Mura Augusto Navone David Pala Pier Augusto Panzalis Antonio Pusceddu Alberto Ruiu Angelo Cau 《水产资源保护:海洋与淡水生态系统》2019,29(4):537-545
409.
Antonello Sala Joana dArc Prat Farran Josefina Antonijuan Alessandro Lucchetti 《Fisheries Research》2009,100(2):156-166
A new door has been designed to reduce hydrodynamic drag coefficient and increase spread of door commonly used in the Mediterranean commercial demersal trawl fisheries. Flume tank testing and engineering sea trials provide data which allow us to illustrate the performance and impact on the seabed of an existing door and a new door design. In the flume tank, each model was tested over a range of attack angles and for a limited range of otterboard heels. Curves of spreading-, drag- and down-force coefficients have been calculated. In the case of sea trials in order to extract the hydrodynamic coefficients an analysis has been applied and a mathematical model was used to calculate attack angle functions. From analysing the differences between engineering sea trials and flume tank tests we have deduced some conclusions about additional ground contact forces on sea trials that affect the performance of the doors. Moreover, a comparison between reaction forces of the flume tank and the estimation of reaction forces at sea has been given. Finally, this study allowed us to notice important differences between traditional and experimental otterboards. 相似文献
410.
Giacomo Fais Alessia Manca Federico Bolognesi Massimiliano Borselli Alessandro Concas Marco Busutti Giovanni Broggi Pierdanilo Sanna Yandy Marx Castillo-Aleman Ren Antonio Rivero-Jimnez Antonio Alfonso Bencomo-Hernandez Yendry Ventura-Carmenate Michela Altea Antonella Pantaleo Gilberto Gabrielli Federico Biglioli Giacomo Cao Giuseppe Giannaccare 《Marine drugs》2022,20(5)
Spirulina is the most studied cyanobacterium species for both pharmacological applications and the food industry. The aim of the present review is to summarize the potential benefits of the use of Spirulina for improving healthcare both in space and on Earth. Regarding the first field of application, Spirulina could represent a new technology for the sustainment of long-duration manned missions to planets beyond the Lower Earth Orbit (e.g., Mars); furthermore, it could help astronauts stay healthy while exposed to a variety of stress factors that can have negative consequences even after years. As far as the second field of application, Spirulina could have an active role in various aspects of medicine, such as metabolism, oncology, ophthalmology, central and peripheral nervous systems, and nephrology. The recent findings of the capacity of Spirulina to improve stem cells mobility and to increase immune response have opened new intriguing scenarios in oncological and infectious diseases, respectively. 相似文献