排序方式: 共有122条查询结果,搜索用时 15 毫秒
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Long-term effects of mouse intracytoplasmic sperm injection with DNA-fragmented sperm on health and behavior of adult offspring 总被引:1,自引:0,他引:1
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Engblom D Bilbao A Sanchis-Segura C Dahan L Perreau-Lenz S Balland B Parkitna JR Luján R Halbout B Mameli M Parlato R Sprengel R Lüscher C Schütz G Spanagel R 《Neuron》2008,59(3):497-508
Cocaine strengthens excitatory synapses onto midbrain dopamine neurons through the synaptic delivery of GluR1-containing AMPA receptors. This cocaine-evoked plasticity depends on NMDA receptor activation, but its behavioral significance in the context of addiction remains elusive. Here, we generated mice lacking the GluR1, GluR2, or NR1 receptor subunits selectively in dopamine neurons. We report that in midbrain slices of cocaine-treated mice, synaptic transmission was no longer strengthened when GluR1 or NR1 was abolished, while in the respective mice the drug still induced normal conditioned place preference and locomotor sensitization. In contrast, extinction of drug-seeking behavior was absent in mice lacking GluR1, while in the NR1 mutant mice reinstatement was abolished. In conclusion, cocaine-evoked synaptic plasticity does not mediate concurrent short-term behavioral effects of the drug but may initiate adaptive changes eventually leading to the persistence of drug-seeking behavior. 相似文献
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Héctor Lorente-Martínez Ainhoa Agorreta María Torres-Sánchez Diego San Mauro 《Organisms Diversity & Evolution》2018,18(4):499-514
Aquaporins are integral membrane proteins that exchange water and small solutes. They played an important role in the colonisation of terrestrial environments by tetrapod ancestors via the appearance of three exclusive paralogs. Like early tetrapods, mudskippers represent an independent case of amphibious lifestyle evolution that is unparalleled by other extant fish groups. Given this lifestyle parallelism and that aquaporins were relevant for tetrapod terrestrialisation, this study examines the aquaporins in mudskippers to investigate whether similar changes in aquaporins could have possibly occurred during their water-to-land transition. We have catalogued aquaporin genes in four mudskipper genomes and studied their diversity and molecular evolution (including detection of positive selection) in a broad phylogenetic context of vertebrates. Our genomic screening returned 55 aquaporin genes for mudskippers (none of them constituting novel paralogs) that can be assigned to 10 different known classes. We detected signatures of positive selection in AQP10a and AQP11b in mudskippers (both the entire clade and the clade containing the most terrestrial species, implying different evolutionary times). This suggests possible alteration of the molecular function of such paralogs caused by changes at specific protein sequence positions, some of them located in relatively close proximity to parts of the molecule involved in pore formation and substrate selectivity. Given the importance of aquaporins for osmotic regulation in fishes, it might be possible that these selective changes (perhaps allowing permeability to new solutes) could have played a role during the adaptation of mudskippers to an amphibious lifestyle. 相似文献
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Development and validation of an automated high-throughput system for zebrafish in vivo screenings 总被引:1,自引:0,他引:1
Letamendia A Quevedo C Ibarbia I Virto JM Holgado O Diez M Izpisua Belmonte JC Callol-Massot C 《PloS one》2012,7(5):e36690
The zebrafish is a vertebrate model compatible with the paradigms of drug discovery. The small size and transparency of zebrafish embryos make them amenable for the automation necessary in high-throughput screenings. We have developed an automated high-throughput platform for in vivo chemical screenings on zebrafish embryos that includes automated methods for embryo dispensation, compound delivery, incubation, imaging and analysis of the results. At present, two different assays to detect cardiotoxic compounds and angiogenesis inhibitors can be automatically run in the platform, showing the versatility of the system. A validation of these two assays with known positive and negative compounds, as well as a screening for the detection of unknown anti-angiogenic compounds, have been successfully carried out in the system developed. We present a totally automated platform that allows for high-throughput screenings in a vertebrate organism. 相似文献
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Ainhoa Magrach José Guitián Asier R. Larrinaga Javier Guitián 《Ecological Research》2011,26(4):851-861
The process of fragmentation can greatly influence plant–animal interactions. To assess the degree to which it affects the
balance between two interactions of opposite sign, namely seed dispersal and post-dispersal seed predation, we selected 16
patches of chestnut forest in O Courel and El Bierzo, northwestern Spain. We assessed the effect of fragmentation over two
different seed dispersal–predation systems using Helleborus foetidus and Ilex aquifolium as model species. In the first case, field experiments consisted of seed-offering trays with selective exclusion of rodents and ants in a two-way
orthogonal design. In the second experiment, we placed experimental branches and trays on the floor to assess seed dispersal
and predation. The interactions between several fragment traits and the relative contribution of rodents, ants and birds to
seed removal were analyzed by means of generalized linear mixed models. Results show that for H. foetidus, differences in seed dispersal–predation were accounted for by patch shape, which affected mainly the dispersal phase. Major
seed dispersal took place in patches with a smaller edge to core ratio and high plant cover (abandoned patches), whilst the
latter also showed maximum seed predation. For I. aquifolium, fragmentation effects were significant only for seed predation, which was increased in abandoned patches. This shows that
the effects of habitat fragmentation can emerge at different phases depending on specific traits of the interacting animals.
It also highlights the importance of traditional land-use practices in species interactions. 相似文献
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