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排序方式: 共有608条查询结果,搜索用时 968 毫秒
91.
Dar-Shong Lin Tzu-Po Chuang Ming-Fu Chiang Che-Sheng Ho Chung-Der Hsiao Yu-Wen Huang Tsu-Yen Wu Jer-Yuarn Wu Yuan-Tsong Chen Tsai-Chuan Chen Ling-Hui Li 《Gene》2014
Xq28 duplications encompassing the methyl CpG binding protein 2 (MECP2) in males exhibit a distinct phenotype, including developmental delay, facial dysmorphism, muscular hypotonia, intellectual disability, poor or absent speech, recurrent infections and early death. The vast majority of affected males inherit the MECP2 duplication from their usually asymptomatic carrier mothers. Only a few cases with Xq28 duplication originating from de novo unbalanced X/Y translocation have been reported and the paternal origin of the aberration has only been validated in three males in the related literature. Here we present a karyotypically normal male with features characteristic of the MECP2 duplication syndrome. The genome-wide SNP genotyping shows a de novo 2.26-Mb duplication from Xq28 to the terminus. The genotypes of the SNPs within the duplicated region indicated a paternal origin. Furthermore, the results of fluorescence in situ hybridization (FISH) indicated a novel Xq:Yp translocation, characterized as der(Y)t(Y;X)(p11.32;q28), which suggests an aberrant that occurred during spermatogenesis. The phenotype is compared to the previously reported cases with Xq28 duplication originated from an unbalanced X/Y translocation, and there was no specific part of the phenotype that could be contributed to the origin of parental imbalances. This report further highlights the capacity of high-molecular cytogenetic methods, such as SNP array and FISH, in the identification of submicroscopic rearrangement, structural configuration and parental origin of aberrant while in the evaluation of children with idiopathic developmental delay and intellectual disability. 相似文献
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93.
Because ecosystems are complex, tradeoffs exist among supplies of multiple ecosystem services, especially between the provisioning and regulating services. In ecosystem processes, net primary production (NPP) is connected with many other processes such as respiration and evapotranspiration. As one key supporting service, NPP is also related to other provisioning and regulating services. This study introduces an analysis framework of ecosystem services tradeoffs from the perspective of varied share of NPP, in the alpine grassland ecosystem of Damxung County on the Tibetan plateau, China. Total NPP was divided into the share of NPP spent on supplying provisioning services and the share used in supporting regulating services. Tradeoffs between provisioning and regulating services were analyzed by quantifying the change of meat provisioning service and the remaining share of NPP used in other ways; the corresponding change in the share of NPP used to support regulating services was also analyzed and compared with other changes in regulating services, such as carbon sequestration and water conservation services. The results show, from 2000 to 2010, the meat provisioning service increased by 199%, but this was at a cost of additional livestock feeding, which used more NPP of the alpine grassland ecosystem. As a result, by 2010 the remaining NPP used for supporting regulating services shrank to 77% of the 2000 level, which was accompanied by a decrease in carbon sequestration and water conservation services by 90% and 67%, respectively. The analysis of tradeoffs from the perspective of variations in the share of NPP used for various services will contribute to the study of mechanisms involved in providing ecosystem services, interactions between the provisioning of various services, and will also help land managers improve the management of ecosystems. 相似文献
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95.
Hiroaki Iidzuka Hideaki Goto Michimasa Yamasaki Naoya Osawa 《Entomological Science》2014,17(2):167-180
Ambrosia beetles (many Scolytinae and all Platypodinae) are one of the most important insect pests for forestry worldwide, but little is known about the community structure of ambrosia beetles in terms of their vertical variations and resource utilization. We clarified the community structure and seasonal population trends of ambrosia beetles on 11 living and three newly dead Fagus crenata Blume trees using individual tube traps placed up to 10 m high from May to November in 2007 and 2008. We captured seven scolytine species (Ambrosiodmus lewisi (Blandford), Euwallacea validus (Eichhoff), Trypodendron proximum (Niisima), Xyleborinus saxeseni (Ratzeburg), Xyleborus atratus Eichhoff, Xylosandrus brevis (Eichhoff) and Xylosandrus germanus (Blandford)) and three platypodine species (Crossotarsus niponicus Blandford, Platypus hamatus Blandford and Platypus severini Blandford). The ambrosia beetles were suggested to breed at species‐specific height ranges, with the equal host resource use per individual among the species. Of the three major species, C. niponicus, P. hamatus and P. severini, two (C. niponicus and P. hamatus) had male‐biased sex ratios, which is considered a reproductive strategy to increase maternal fitness. Morphological characteristics of the mandibles may play an important role in the difference of sex roles on reproduction in the three major species. 相似文献
96.
选取26个性状,应用不加权算术平均配对法对来自云南各地的20份紫苏试材进行了数值分类学研究。结果表明:这20份紫苏试材可分成紫苏、回回苏、耳齿紫苏、野生紫苏和白苏5个变种;并对白苏变种的设立和耳齿紫苏变种的分布进行了探讨。 相似文献
97.
The onychopod cladoceran Cercopagis that recently invaded the Baltic Sea is reported from new zones of the northern Baltic proper. Because of successful survival and an expanding distribution range, the addition of Cercopagis to the Baltic fauna is considered to be permanent. What has previously been cited as Cercopagis pengoi encompasses the morphology of several other species, subspecies and forms. Either a number of morphologically similar species is present, or there is a number of spurious species in Cercopagis. The last hypothesis is favoured. The spatial distribution pattern of Cercopagis, as well as that of total zooplankton, was correlated with depth. Deep (>100 m) and shallow (<10 m) stations had significantly lower abundance than stations of intermediate depth (<100 m). An overview of the distribution of C. pengoi group in fresh and brackish waters suggests a high tolerance to environmental factors, but with differences among taxa. Due to this ecological flexibility, the colonization of the Baltic is not unexpected. Increasing salinity may restrict dispersal of cercopagids to the southern areas of the Baltic and to the North Sea, but inland lakes (e.g. in Sweden) present an ecological profile suitable for colonization. 相似文献
98.
99.
JAN ZIMA VITALI A. GAICHENKO† MILO MACHOLÁN SEVIL I. RADJABLI‡ OLGA V. SABLINA‡ JAN M. WÓJCIK§ 《Biological journal of the Linnean Society. Linnean Society of London》1990,41(1-3):229-233
We examined the karyotypes of 212 specimens of the house mouse obtained from 44 localities in central and eastern Europe, and several regions of Asia. The Robertsonian chromosome fusion 5.12 was found in a population of Mus musculus musculus in Czechoslovakia. Two large HSRs on chromosome 1 were ascertained in four female mice from western Siberia. In most of the localities under study, the mice possessed a normal karyotype with 40 acrocentric chromosomes. 相似文献
100.
Nicole Raynaud Brigitte Moreteau Nicole Chaminade et Gérard Nicolas 《Entomologia Experimentalis et Applicata》1985,39(1):43-46
Un apport unique de 10 g d'hormone juvénile 1, réalisé chez des criquets du dernier stade larvaire à corpora allata intacts ou préalablement soumis à une application de precocène 2, provoque, à la mue suivante, l'apparition d'individus dont les caractéristiques sont intermédiaires entre celles du dernier stade larvaire et celles de l'imago. Cependant, les criquets traités par le précocène 2 présentent des variations phénotypiques plus prononcées, se traduisant par un maintien accru des caractéristiques larvaires. Les études ultrastructurales montrent que les corpora allata dégénèrent rapidement sous l'action des 400 g de précocène 2.
Summary In fifth instar locusts, with intact corpora allata or previously subjected to precocene 2 action, a single injection of 10 g juvenile hormone 1 leads, at the next molt, to the appearance of individuals displaying characters ranging from the typical larval to the typical imaginal ones. But, unexpectedly, the phenotypic variations are more marked in the precocene 2 treated locusts, and are typified by an increased retention of larval characters. Electron microscopic studies indicate that the use of 400 g of precocene 2 rapidly leads to the degeneration of the corpora allata.相似文献