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排序方式: 共有1354条查询结果,搜索用时 31 毫秒
671.
Philippe Charron Delphine Héron Marcela Gargiulo Josué Feingold Jean-François Oury Pascale Richard Michel Komajda 《黑龙江环境通报》2004,24(9):701-703
Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disease that may cause premature sudden death, especially in teenagers and young adults. The recent progress in the molecular genetics of the disease has made genetic testing sometimes available in clinical practice. We report the case of a couple who still requested prenatal molecular testing after detailed information had been given through a multidisciplinary consultation. Prenatal diagnosis in HCM is associated with complex medical and psychological implications, in addition to general ethical considerations, as the potential value of the diagnosis is counterbalanced by the highly variable expression of the disease and the difficulty in predicting its evolution. The R403L mutation in the MYH7 gene had been previously identified in this family, characterized by a malignant form of HCM. In the specific context of this case, we decided to agree to the request of the parents and performed the prenatal diagnosis. To the best of our knowledge, this is the first report of a prenatal molecular diagnosis performed in the context of HCM. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
672.
Jochem K. H. Spoor Lis van Gastel Fatima Tahib Amanda van Grieken Willem van Weteringen Frank Sterke Ahmet A. Baschat Jena L. Miller Tjeerd H. R. de Jong René M. H. Wijnen Alex E. Eggink Philip L. J. DeKoninck 《黑龙江环境通报》2023,43(3):355-358
Objective
To develop a realistic simulation model for laparotomy-assisted fetoscopic spina bifida aperta (SBa) surgery, to be used for training purposes and preoperative planning.Methods
The predefined general requirement was a realistic model of an exteriorized uterus, allowing all neurosurgical steps of the intervention. The uterus was modelled using ultrasound and MRI images of a 25 weeks’ gravid uterus, consisting of flexible polyurethane foam coated with pigmented silicone. The fetal model, contained an opening on the dorsal side for a customizable spinal insert with all the aspects of a SBa, including a cele, placode, and myofascial and skin layer. The model was assessed in a series of validation experiments.Results
Production costs are low, uterus and fetus are reusable. Placental localization and the level and size of the spinal defect are adjustable, enabling case-specific adaptations. All aspects of the simulator were scored close to realistic or higher for both appearance and functional capacities.Conclusions
This innovative model provides an excellent training opportunity for centers that are starting a fetoscopic SBa repair program. It is the first simulation model with adjustable spinal defect and placental localisation. Further objective validation is required, but the potential for using this model in preoperative planning is promising. 相似文献673.
Betsabé Ruiz-Guerra Noé Velázquez Rosas Juan Carlos López-Acosta 《Environmental management》2014,54(3):656-667
This study analyzes the potential uses of live fences and pastures as reservoirs of plant diversity for two regions with different management histories, Los Tuxtlas (LT) and Uxpanapa (UX), Veracruz, México. We studied two habitats, live fences and pastures, analyzed their species richness, diversity, structure and plant composition and classified species according to plant regeneration modes (light-demanding and shade tolerant), seed dispersal syndrome and their local uses. We recorded 62 species of trees at LT and 48 at UX. Live fences were more diverse than pastures in both regions. The LT site showed to analyze the relationship a higher diversity of plants in regeneration stages than the one at UX. However, UX had higher diversity of adult plants in the pastures than LT. Composition and structure of live fences were different between regions, as well as within live fences and pastures, 53 % of species were light-demanding and 40 % were shade tolerant; 70 % of the species were dispersed by birds. Differences between sites are associated with the modifications in live fences structure, which changed according to managerial practices and the use of local species; this may influence plant regeneration modes as well as the visits of avian dispersal agents. In LT, all species found in live fences were useful to humans, whereas in UX, less than half were used by the local population. Our results underline the importance of live fences and isolated trees in pasture habitats as potential sites to host native and useful species from tropical rain forests in livestock landscapes. 相似文献
674.
de Araujo Helder F. P. Machado Célia C. C. Alves Ana Carolina Flores da Costa Lima Mônica da Silva José Maria Cardoso 《Mitigation and Adaptation Strategies for Global Change》2022,27(8):1-18
Mitigation and Adaptation Strategies for Global Change - All Clean Development Mechanism (CDM) projects are designed to contribute to the sustainable development of the host country. Livelihood is... 相似文献
675.
Naiara Albaina Jeanine L. Olsen Lucía Couceiro José Miguel Ruiz Rodolfo Barreiro 《Marine Biology》2012,159(9):1871-1884
Because marine species respond differentially to factors governing survival and gene flow, closely related taxa may display dissimilar phylogeographic histories. New data for the patchily distributed gastropod Nassarius nitidus throughout its Atlantic–Mediterranean range (collected during 2008 and 2009) were used to investigate its phylogeography and recent demography. Results based on mitochondrial COI sequences of 422?N. nitidus individuals from 15 localities revealed contrasting phylogeographic and demographic patterns among N. nitidus populations from each basin. Data suggest the existence of two glacial refugia, one in the Atlantic, around the Iberian Peninsula, and the other in the Paleo-Mediterranean Sea (Adriatic). Bayesian skyline reconstructions suggest that the Adriatic population of N. nitidus remained largely unaffected by the Last Glacial Maximum (LGM), whereas the Iberian Atlantic region experienced dramatic exponential growth after its conclusion. Contemporary North Sea populations of N. nitidus are the endpoint of a leading-edge recolonization process from a southern position. Additionally, a reanalysis of pre-existing material for the continuously distributed close congener N. reticulatus was used to compare both species in the late histories. In contrast to N. nitidus, N. reticulatus prospered during the LGM and experienced an earlier Atlantic expansion during the previous interglacial period. Despite similar life history and dispersal potential, the results here presented suggest that subtle differences in microhabitat requirements between the two species have had important consequences for their particular distribution in response to glacial events. 相似文献
676.
Eduardo Madrigal-Santillán Eduardo Madrigal-Bujaidar Alicia Reyes-Arellano José Antonio Morales-González Isela Álvarez-González Manuel Sánchez-Gutiérrez 《毒物与环境化学》2019,101(7-8):369-388
AbstractGlucomannan is a highly branched polysaccharide with glycosidic linkages, constituted of mannoses and glucoses. In recent years, its usefulness due to its immunological, antioxidant and antimutagenic activity has been recognized. The aim of the study was to determine the antigenotoxic ability of glucomannan extracted from Candida utilis orally administered (100–700?mg/kg) to mice, which subsequently received 1?mg/kg aflatoxin B1. Hepatocytes obtained from these animals 4–16?h post administration were examined by means of the comet assay. The antigenotoxic effect was found to be higher than that observed in previous studies with α-mannan and β-D-glucan isolated from Saccharomyces cerevisiae., In order to explore the possibility of formation of a supramolecular complex between glucomannan and aflatoxin B1, both compounds were co-crystallized, their melting points determined, and the complex analyzed through ultraviolet spectroscopy. The spectroscopy data suggest that the protective effect of glucomannan is related to the formation of a supramolecular complex between the two compounds. 相似文献
677.
678.
Tiago José Pereira Gustavo Fonseca Manuel Mundo-Ocampo Betânia Cristina Guilherme Axayácatl Rocha-Olivares 《Marine Biology》2010,157(8):1665-1678
We used morphological and molecular approaches to evaluate the diversity of free-living marine nematodes (order Enoplida)
at four coastal sites in the Gulf of California and three on the Pacific coast of Baja California, Mexico. We identified 22
morphological species belonging to six families, of which Thoracostomopsidae and Oncholaimidae were the most diverse. The
genus Mesacanthion (Thoracostomopsidae) was the most widespread and diverse. Five allopatric species, genetically and morphologically differentiated,
were found in two localities in the Gulf of California (M. sp1 and M. sp2) and three in the Pacific coast (M. sp3, M. sp4 and M. sp5). Overall, we produced 19 and 20 sequences for the 18S and 28S genes, respectively. Neither gene displayed intraspecific
polymorphisms, which allowed us to establish that some morphological variation was likely either ontogenetic or due to phenotypic
plasticity. Although 18S and 28S phylogenies were topologically congruent (incongruence length difference test, P > 0.05), divergences between species were much higher in the 28S gene. Moreover, this gene possessed a stronger phylogenetic
signal to resolve relationships involving Rhabdodemania and Bathylaimus. On the other hand, the close relationship of Pareurystomina (Enchilidiidae) with oncholaimids warrants further study. The 28S sequences (D2D3 domain) may be better suited for DNA barcoding
of marine nematodes than those from the 18S rDNA, particularly for differentiating closely related or cryptic species. Finally,
our results underline the relevance of adopting an integrative approach encompassing morphological and molecular analyses
to improve the assessment of marine nematode diversity and advance their taxonomy. 相似文献
679.
Olivier Pays Simon P. Blomberg Pierre-Cyril Renaud François-René Favreau Peter J. Jarman 《Behavioral ecology and sociobiology》2010,64(3):443-454
In group-forming prey species, theory assumes that individuals within groups should scan independently of one another, with
vigilance sequences being relatively unpredictable, making interscan durations highly variable. We attempted to detect any
divergence from randomness in the scanning process in three mammalian prey species phylogenetically and geographically separated
and exposed to different levels of predation: waterbuck, Kobus ellipsiprymnus defassa, under a high observed predation risk, eastern grey kangaroo, Macropus giganteus, still experiencing occasional predation and European roe deer, Capreolus capreolus, under a very low natural predation risk. Our results revealed that the focal interscan duration increased when the duration
of the preceding interscan increased, whatever the studied species and the predation risk that its individuals experienced,
and decreased with the preceding scan duration in two species under, respectively, occasional and low predation risks. The
exponential distribution was the tested model that fitted the observed distributions of interscan durations least well. We
discuss what can trigger non-randomness in scanning, through a non-homogenous Poisson process, at both intra-individual and
inter-individual levels, particularly with regard to previous studies that have demonstrated synchronisation of vigilance
in such mammals. Our results suggest the need to reconsider any assumption of randomness in scanning in the basic model predicting
form and frequency of scanning behaviour by prey species. 相似文献
680.
René E. van Dijk Lidia A. Mészáros Marco van der Velde Tamás Székely Ákos Pogány János Szabad Jan Komdeur 《Behavioral ecology and sociobiology》2010,64(9):1425-1435
Engagement in extra-pair copulations is an example of the abundant conflicting interests between males and females over reproduction.
Potential benefits for females and the risk of cuckoldry for males are expected to have important implications on the evolution
of parental care. However, whether parents adjust parental care in response to parentage remains unclear. In Eurasian penduline
tits Remiz pendulinus, which are small polygamous songbirds, parental care is carried out either by the male or by the female. In addition, one
third of clutches is deserted by both male and female. Desertion takes place during the egg-laying phase. Using genotypes
of nine microsatellite loci of 443 offspring and 211 adults, we test whether extra-pair paternity predicts parental care.
We expect males to be more likely to desert cuckolded broods, whereas we expect females, if they obtain benefits from having
multiple sires, to be more likely to care for broods with multiple paternity. Our results suggest that parental care is not
adjusted to parentage on an ecological timescale. Furthermore, we found that male attractiveness does not predict cuckoldry,
and we found no evidence for indirect benefits for females (i.e., increased growth rates or heterozygosity of extra-pair offspring).
We argue that male Eurasian penduline tits may not be able to assess the risk of cuckoldry; thus, a direct association with
parental care is unlikely to evolve. However, timing of desertion (i.e., when to desert during the egg-laying phase) may be
influenced by the risk of cuckoldry. Future work applying extensive gene sequencing and quantitative genetics is likely to
further our understanding of how selection may influence the association between parentage and parental care. 相似文献