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121.
Alfredo Nazzaro Matteo Della Monica Fortunato Lonardo Arturo Di Blasi Maria Baffico Maurizia Baldi Giovanni Nazzaro Giuseppe De Placido Gioacchino Scarano 《黑龙江环境通报》2004,24(11):918-922
Pfeiffer syndrome is characterized by bilateral coronal craniosynostosis, midface hypoplasia, beaked nasal tip, broad and medially deviated thumbs and great toes. Originally, it was described in eight persons from three generations in a pedigree consistent with an autosomal dominant transmission. Since then, several reports have documented its high clinical and genetic heterogeneity. The condition is usually detected in the newborn period or later, and very few prenatal ultrasound diagnoses have been reported. We present a case of Pfeiffer syndrome prenatally diagnosed at 20 weeks' gestation, in which the sonographic features of craniosynostosis, hypertelorism associated with an extreme proptosis, and broad thumb led to the diagnosis, confirmed after termination of pregnancy by dysmorphological, pathological and radiological evaluation. DNA analysis of the fibroblast growth factor receptor 2 (FGFR2) showed a missense mutation consisting in a transversion G → C at nucleotide 870. This led to a Trp290Cys amino acidic substitution. We discuss the relevant findings of our and previously published cases. Our report demonstrates that a careful sonographic examination can lead to an early prenatal diagnosis of Pfeiffer syndrome also in cases without cloverleaf skull. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
122.
Matteo Della Monica Alfredo Nazzaro Fortunato Lonardo Gerardo Ferrara Arturo Di Blasi Gioacchino Scarano 《黑龙江环境通报》2005,25(5):394-397
A case of cloacal exstrophy (CE) was detected by ultrasound as early as 22 weeks of gestation in association with myelocystocele complex, an unusual form of occult spinal dysraphism often associated with such a disease. The ultrasonographic diagnosis was made through the detection of a wavy cord-like segment of soft tissue protruding from the anterior abdominal wall, just below the umbilical cord insertion, strongly resembling the trunk of an elephant. Our article enforces the suggestion that the ultrasound elephant trunk–like image should be added to the existing major criteria for making prenatal diagnosis of CE. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
123.
Summary Many lizards autotomize their tails to escape when grasped by a predator. It is hypothesized that tail loss causes a reduction in social status, thereby potentially lowering their reproductive success. We experimentally induced tail loss in Lacerta monticola in a semi-natural enclosure, and show that tail loss reduced social status and mating access in males. Tailless males increased body mass more rapidly than tailed dominant males, probably due to lower aggression costs. Also, tailless females were courted less and copulated less than tailed females, supporting the hypothesis that tail loss decreases reproduction potential.Correspondence to: J. Martin 相似文献
124.
Santiago Guillermo Ceballos Enrique Pablo Lessa Mariela Fernanda Victorio Daniel Alfredo Fernández 《Marine Biology》2012,159(3):499-505
Phylogeography studies add insights into the geographic and evolutionary processes that underline the genetic divergence of
populations. This work examines the geographic genetic structure of the Patagonian blennie, Eleginops maclovinus, a notothenioid (Perciformes) endemic to South American temperate and sub-Antarctic waters, using mitochondrial DNA cytochrome
b sequences. We found 58 haplotypes in the analysis of 261 individual sequences of 833 base pairs in length. Among-population
variance was very low (1.62%) and many haplotypes were shared between several populations across the species geographic range.
Genetic differentiation was not consistent with a simple model of isolation by distance, possibly suggesting a lack of equilibrium
between gene flow and local genetic drift. The analysis of mismatch distributions, neutrality tests, and the Bayesian Skyline
Plot showed a pattern consistent with a recent population expansion event that may have taken place during the Middle Pleistocene. 相似文献
125.
Nagler P Glenn EP Hursh K Curtis C Huete A 《Environmental monitoring and assessment》2005,109(1-3):255-274
A vegetation mapping system for change detection was tested at the Havasu National Wildlife Refuge (HNWR) on the Lower Colorado
River. A low-cost, aerial photomosaic of the 4200 ha, study area was constructed utilizing an automated digital camera system,
supplemented with oblique photographs to aid in determining species composition and plant heights. Ground-truth plots showed
high accuracy in distinguishing native cottonwood (Populus fremontii) and willow (Salix gooddingii) trees from other vegetation on aerial photos. Marsh vegetation (mainly cattails, Typha domengensis) was also easily identified. However, shrubby terrestrial vegetation, consisting of saltcedar (Tamarix ramosissima), arrowweed (Pluchea sericea), and mesquite trees (Prosopis spp.), could not be accurately distinguished from each other and were combined into a single shrub layer on the final vegetation
map. The final map took the form of a base, shrub and marsh layer, which was displayed as a Normalized Difference Vegetation
Index map from a Landsat Enhanced Thematic Mapper (ETM+) image to show vegetation intensity. Native willow and cottonwood
trees were digitized manually on the photomosaic and overlain on the shrub layer in a GIS. By contrast to present, qualitative
mapping systems used on the Lower Colorado River, this mapping system provides quantitative information that can be used for
accurate change detection. However, better methods to distinguish between saltcedar, mesquite, and arrowweed are needed to
map the shrub layer. 相似文献
126.
Mendoza-Salgado RA Lechuga-Devéze CH Ortega-Rubio A 《Journal of environmental management》2005,75(2):183-187
At Ensenada de La Paz, a coastal lagoon on the western side of the Gulf of California, nutrient and salinity data before and after rain events were evaluated using a mass balance model to estimate the exchange of conservative and non-conservative variables with the adjacent sea. Surface salinity, nitrogen (N-NO3, N-NO2), and phosphorus (PO4) were used in the model to obtain the hydraulic balance, water residence time, and nitrogen and phosphorus fluxes. Results showed that residual volume was mainly influenced by evaporation. Rainfall and runoff increased the mixed volume and reduced water residence time. Pre-rainfall hydraulic balance conditions were reestablished about 10 days after a rain storm. Rainwater inputs also modified the quality of the coastal lagoon: the pre-rainfall scenario showed that more nitrogen is consumed than produced, and there is a phosphorus sufficiency. A rain disturbance induces a nitrogen and phosphorus increase. Eleven days after a rain storm, nitrogen and phosphorus levels did not return to the pre-rainfall scenario. Rain disturbances in arid zone coastal lagoons modify their water quality and exchange with the adjacent ocean; some management strategies are suggested. 相似文献
127.
128.
María V. Coll Aráoz María I. Mercado Alfredo Grau César A. N. Catalán 《Chemoecology》2016,26(4):143-151
According to theory, variation in plant secondary metabolism against herbivores is driven by variation in biotic and abiotic conditions interacting with plants genotype to determine the expression of resistance traits. Particularly, it has been long postulated that plants growing along latitudinal gradients experience changes in biotic and abiotic interactions, specifically leading to a decrease of plant toxicity towards the poles. We tested this hypothesis using the asteraceous species Smallanthus macroscyphus. Smallanthus species are known to contain sesquiterpene lactones (STLs), bitter compounds with a broad spectrum of biological activities, including deterrence to herbivores. S. macroscyphus showed a decrease in chemical diversity of STLs when investigating populations growing from the tropical regions to less tropical ones. Populations from lower latitudes were found to be more chemically diverse with enhydrin, uvedalin and fluctuanin as main components, while populations southward were chemically fairly uniform, with polymatin A as the main and largely dominant STL. The STL chemistry of S. macroscyphus is in agreement with the hypothesis that plants of tropical forests have a greater diversity of secondary metabolites when compared to their temperate counterparts. 相似文献
129.
Clarissa Vilela Figueiredo da Silva Campos Laenne Barbara Silva de Moraes Renata da Silva Farias William Severi Luis Otavio Brito Alfredo Olivera Gálvez 《Chemistry and Ecology》2013,29(10):903-921
ABSTRACTKnowledge about phytoplankton communities is important for aquaculture due to their influence on environmental variables. The goal of the study was to evaluate the ecological effect of seaweed Gracilaria birdiae at three different densities: 2.5 (LG2.5); 5.0 (LG5.0) and 7.5?kg m?3 (LG7.5), on water quality variables and the phytoplankton communities in integrated aquaculture systems (shrimp and seaweed) with a control (without seaweed) (LB) using biofloc technology. Settleable and total suspended solids were significantly correlated with the phytoplankton groups. In addition, orthophosphate was the main variable controlling phytoplankton growth and gross primary production. No significant differences were identified among the treatments in terms of the phytoplankton assemblages (p?>?0.05) but differences were found between the communities (ANOSIM, R global?=?0.873) in relation to the days of the experiment. However, the LG2.5 treatment had higher diversity and lower species dominance, as well as higher productivity and final shrimp weight. The results indicate that seaweed inhibit phytoplankton growth, mainly of toxic species. They suggest that phytoplankton composition in integrated aquaculture systems in the presence of seaweed at a density of 2.5?kg m?3 is more diversified and provides better water quality and shrimp performance by inhibiting the abundance of harmful species. 相似文献
130.
Luis Otavio Brito Leônidas de Oliveira Cardoso Junior Henrique David Lavander Jéssika Lima de Abreu William Severi Alfredo Olivera Gálvez 《Chemistry and Ecology》2018,34(10):901-913
The aim of this study was to evaluate the bioremediation of effluents in the biofloc culture of shrimp juveniles using clams, seaweed and fish. Four treatments were considered: CLT – without bioremediating organisms; AB – using Anomalocardia brasiliana; GB – using Gracilaria birdiae and ON – using Oreochomis niloticus with 2.5?kg wet weight per m3 of shrimp effluent. In the AB treatment, significant differences were observed in the effluent at the end of the experiment (96?h) for values of nitrite-nitrogen, nitrate, alkalinity, TSS and orthophosphate. The ISS and VSS levels recorded for the AB treatment varied respectively from 336 to 127?mg?L?1, and from 505 to 130?mg?L?1, with a corresponding gradual reduction of approximately 62% and 74% at the end of the experiment. The use of a clam species to treat effluents in a biofloc system with salinity near 25?g?L?1 reduced waste solids and increased the nitrification process from 72 to 96?h, indicating that this clam can be used as a bioremediator and contributes to effluent treatment in shrimp. 相似文献