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51.
Susy Echeverría‐Londoño Tim Newbold Lawrence N. Hudson Sara Contu Samantha L. L. Hill Igor Lysenko Enrique Arbeláez‐Cortés Inge Armbrecht Teun Boekhout Jimmy Cabra‐García Yamileth Dominguez‐Haydar Guiomar Nates‐Parra Doris L. Gutiérrez‐Lamus Diego Higuera Paola Johanna Isaacs‐Cubides Carlos A. López‐Quintero Eliana Martinez Daniel Rafael Miranda‐Esquivel Luis Eduardo Navarro‐Iriarte Jorge Ari Noriega Samuel Eduardo Otavo Alejandro Parra‐H Katja Poveda Martha P. Ramirez‐Pinilla Juan Carlos Rey‐Velasco Loreta Rosselli Allan H. Smith‐Pardo José Nicolás Urbina‐Cardona Andy Purvis 《Diversity & distributions》2016,22(11):1099-1111
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Marcelo C. Teixeira Geraldo Mäder Gustavo A. Silva‐Arias Sandro L. Bonatto Loreta B. Freitas 《Botanical journal of the Linnean Society. Linnean Society of London》2016,180(3):348-364
The Brazilian Atlantic Rainforest is one of the most diverse and threatened ecoregions on the planet and displays high levels of endemism. Despite several population analyses and phylogeographical studies, the origins of its species richness and the evolutionary processes that gave rise to this diversification remain poorly understood, especially at the southern edge of the Atlantic Forest. Passiflora actinia is an indigenous species from the southern Atlantic Forest and, as such, was influenced by climatic changes during the Pleistocene. In this study, we investigated the effects of past climate changes on the genetic diversity of P. actinia, using nuclear and plastid markers. We subsequently suggest strategies for the preservation of this species in particular and the whole ecoregion in general. We employed phylogeographical methods and combined these results with past, present and future ensemble niche models. Genetic variability in P. actinia was similar to that of other species with similar geographical distributions, and geographical structuring was not observed based on either type of genetic marker. Diversification in P. actinia was dated to the Pleistocene, suggesting that climate changes could have influenced the distribution of genetic diversity in this species. Our results predicted that suitable P. actinia habitat will persist in the highlands but will be reduced in the lowlands, especially with higher greenhouse gas concentrations. Conservation efforts should focus on populations with unique genetic units and populations from areas with greater climatic instability. Habitat loss due to deforestation in the Atlantic Forest constitutes a major risk to this species, especially to small populations or those with low diversity indices. 相似文献
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Joery den Hoed Elke de Boer Norine Voisin Alexander J.M. Dingemans Nicolas Guex Laurens Wiel Christoffer Nellaker Shivarajan M. Amudhavalli Siddharth Banka Frederique S. Bena Bruria Ben-Zeev Vincent R. Bonagura Ange-Line Bruel Theresa Brunet Han G. Brunner Hui B. Chew Jacqueline Chrast Loreta Cimbalistienė Lisenka E.L.M. Vissers 《American journal of human genetics》2021,108(2):346-356
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Priscilla M. Zamberlan Izabella M. C. Rodrigues Geraldo Mäder Luana Castro João R. Stehmann Sandro L. Bonatto Loreta B. Freitas 《Botanical journal of the Linnean Society. Linnean Society of London》2015,177(3):322-334
Subtribe Withaniinae (Solanaceae) comprises seven genera and c. 40 species, with an almost cosmopolitan distribution. Athenaea and Aureliana are exclusively South American, with diversity centres in the Brazilian Atlantic Rainforest. The generic status of Athenaea and Aureliana was investigated using molecular phylogenetic analysis of five plastid regions (ndhF gene, trnL intron and trnL‐trnF, psaI‐accD and trnC‐ycf6 intergenic spacers), nuclear internal transcribed spacers (ITS) and morphometric analysis of the calyx. Divergence time estimates were also performed. Withaniinae was recovered as monophyletic. The diversification time estimated for Withaniinae was 6.3 Myr, and the estimated diversification time for the Athenaea and Aureliana clades was 2.3 Myr. Athenaea and Aureliana species formed a strongly supported clade. However, the genera were not monophyletic, and support for internal relationships was moderate to weak. The morphometric analysis of the increasing size of the fruit calyx that included all species of the genera showed a cline that did not allow us to conclude that the species could be separated into two genera. Because the accrescent calyx is the only morphological character that distinguishes them, we recognize Athenaea as a synonym of Aureliana and propose five new combinations. The list of accepted species is presented. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 00 , 000–000. 相似文献
55.
Adaptation and Acclimation of Photosynthetic Microorganisms to Permanently Cold Environments 总被引:5,自引:0,他引:5
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Rachael M. Morgan-Kiss John C. Priscu Tessa Pocock Loreta Gudynaite-Savitch Norman P. A. Huner 《Microbiological reviews》2006,70(1):222-252
Persistently cold environments constitute one of our world's largest ecosystems, and microorganisms dominate the biomass and metabolic activity in these extreme environments. The stress of low temperatures on life is exacerbated in organisms that rely on photoautrophic production of organic carbon and energy sources. Phototrophic organisms must coordinate temperature-independent reactions of light absorption and photochemistry with temperature-dependent processes of electron transport and utilization of energy sources through growth and metabolism. Despite this conundrum, phototrophic microorganisms thrive in all cold ecosystems described and (together with chemoautrophs) provide the base of autotrophic production in low-temperature food webs. Psychrophilic (organisms with a requirement for low growth temperatures) and psychrotolerant (organisms tolerant of low growth temperatures) photoautotrophs rely on low-temperature acclimative and adaptive strategies that have been described for other low-temperature-adapted heterotrophic organisms, such as cold-active proteins and maintenance of membrane fluidity. In addition, photoautrophic organisms possess other strategies to balance the absorption of light and the transduction of light energy to stored chemical energy products (NADPH and ATP) with downstream consumption of photosynthetically derived energy products at low temperatures. Lastly, differential adaptive and acclimative mechanisms exist in phototrophic microorganisms residing in low-temperature environments that are exposed to constant low-light environments versus high-light- and high-UV-exposed phototrophic assemblages. 相似文献
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Lucia Vitaioli Emilia Baldoni Anna Gobbetti Loreta Bellini 《The Histochemical journal》1988,20(5):301-307
Summary The effects of progesterone treatment on arylsulphatase activity were studied histochemically and biochemically in the frog oviduct under different experimental conditions. In ovariectomized animals, the hormone induced a large increase in enzyme activity, while in hypophysectomized ones there was a large decrease in this activity. These results indicate that the facilitatory and inhibitory effects of progesterone on arylsulphatase activity are influenced by the presencein situ of the gonad. Hypotheses are advanced to explain different effects of the progesterone treatment. 相似文献
58.
Dornelles CL Bonatto SL De Freitas LB Salzano FM 《American journal of physical anthropology》2005,127(4):439-448
A total of 1,159 mitochondrial DNA samples from two Mongolian, two Siberian, and 25 South Native American populations was surveyed for the presence of the C16278T mutation, frequently found in haplogroup X. Material from 25 carriers of that mutation was then sequenced for the hypervariable segment I (HVS-I) control region, and those that still were not classifiable in classical Amerindian haplogroups were further studied. The tests involved all the control region, as well as the presence of characteristic mutations in seven coding fragments, totalling 5,760 base pairs. The results indicate that haplogroup X is not present in these samples. 相似文献
59.
We report on an 18-year-old Lithuanian girl with hepatosplenomegaly noticed at birth, which progressed thereafter. The patient had to wait about 17 years for an accurate diagnosis and appropriate therapy. Lactase deficiency, congenital cataract of the right eye, and osteoporosis were observed. Episodes of drowsiness were caused by intake of high-protein food. Laboratory findings included slight hyperammonaemia, high plasma Citr, Ala, Gly, Glu, Ser levels, as well as citrullinuria, lysinuria, glutaminuria, alaninuria, argininuria, prolinuria, hydroxyprolinuria, ornithinuria, and orotic aciduria. Aversion to high-protein diet strongly suggested a disorder resulting in hyperammonaemia. Citrullinaemia was suspected. Subsequently the diagnosis of LPI was made on the basis of biochemical and clinical features. Molecular genetic testing revealed a mutation in the SLC7A7 gene, confirming the diagnosis. 相似文献
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Loreta M. Medina Carmen Maria Trujillo Carmen Diaz Luis Puelles 《Journal of morphology》1990,205(1):123-134
Development of neurons in the area triangularis of Gallotia galloti was investigated in Golgi-impregnated brain tissue. Four major neuronal types present in adults were found to originate from two migratory neuroblast types, which were followed from embryonic stage S.32. One type has a thick main medial process, whereas the second type has a long main lateral process. As they migrate toward the periphery of the nucleus, morphological characteristics of maturation appear, including growth cones, filopodia, and outgrowth of axons. Neuroblasts with a main lateral process differentiate into two immature neuronal types, bipolars and pyramidals, observed at S.33 and thereafter. The neuroblasts with a main medial process undergo some somatic translocation through a transitory tangential shaft. Then they develop into monopolar immature forms with a long varicose medial, process, appearing from S.36. onward. Immature bipolar neurons do not experience great changes in their dendritic arborization during development to the adult stage, but pyramidals and monopolars undergo a rapid development of the dendritic tree after S.36. By S.38 archetypes of adult neuronal forms are established. Hairlike appendages first appear on neurons at S.36 They decrease suddenly in S.38 and then proliferate in S.39 when spines first appear. Around the time of hatching, the hairlike appendages begin to disappear and spines become established. Reduction of spines occurs after hatching and continues to the adult stage. Possible influences of several external factors on neuronal maturation are discussed. 相似文献