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71.
German Antonio Villanueva-Bonilla Suyen Safuan-Naide João Vasconcellos-Neto 《Journal of Natural History》2018,52(5-6):361-376
Numerous phenological studies on spiders belonging to the families Oxyopidae, Thomisidae, Lycosidae, Selenopidae (e.g. Selenops cocheleti) and Salticidae (e.g. Psecas chapoda and Psecas viridipurpureus) have been conducted in the neotropical region. However, studies that simultaneously compare population dynamics and age structure in populations of sympatric species are limited, especially in Oxyopidae. The population dynamics and phenology of two congeneric lynx spider (Peucetia rubrolineata and Peucetia flava) were examined in southeastern Brazil. Several characteristics of the age structure were compared between the two spider species. The variation in the total abundance of individuals and age structure and their relationship with climatic variables were similar between the two spiders. Adults of these spiders were present mainly in spring, indicating an annual reproductive cycle and a ‘stenochronous spring’ phenological pattern. The recruitment of spiders occurred in summer for P. rubrolineata and P. flava, followed by successive phenological peaks at all stages of development. Rainfall and temperature had a positive correlation to population flux in the two spider species studied. Despite the significant climatic effects observed in the Serra do Japi, the phenological pattern of the population in this study was not always repeated in other species of spiders (e.g. Selenops cocheleti). 相似文献
72.
Andrzej Górski Ewa Jończyk-Matysiak Marzanna Łusiak-Szelachowska Ryszard Międzybrodzki Beata Weber-Dąbrowska Jan Borysowski 《Cellular and molecular life sciences : CMLS》2018,75(4):589-595
In addition to their established role as a physical barrier to invading pathogens and other harmful agents, intestinal epithelial cells (IEC) are actively involved in local immune reactions. In the past years, evidence has accumulated suggesting the role of IEC in the immunopathology of intestinal inflammatory disorders (IBD). Recent advances in research on bacteriophages strongly suggest that—in addition to their established antibacterial activity—they have immunomodulating properties that are potentially useful in the clinic. We suggest that these immunomodulating phage activities targeting IEC may open novel treatment perspectives in disorders of the alimentary tract, particularly IBD. 相似文献
73.
Jonghee Han Sunmin Jung Jiyeon Jang Tae-In Kam Hyunwoo Choi Byung-Ju Kim Jihoon Nah Dong-Gyu Jo Toshiyuki Nakagawa Masaki Nishimura Yong-Keun Jung 《Cellular and molecular life sciences : CMLS》2014,71(13):2561-2576
The gamma (γ)-secretase holoenzyme is composed of four core proteins and cleaves APP to generate amyloid beta (Aβ), a key molecule that causes major neurotoxicity during the early stage of Alzheimer’s disease (AD). However, despite its important role in Aβ production, little is known about the regulation of γ-secretase. OCIAD2, a novel modulator of γ-secretase that stimulates Aβ production, and which was isolated from a genome-wide functional screen using cell-based assays and a cDNA library comprising 6,178 genes. Ectopic expression of OCIAD2 enhanced Aβ production, while reduction of OCIAD2 expression suppressed it. OCIAD2 expression facilitated the formation of an active γ-secretase complex and enhanced subcellular localization of the enzyme components to lipid rafts. OCIAD2 interacted with nicastrin to stimulate γ-secretase activity. OCIAD2 also increased the interaction of nicastrin with C99 and stimulated APP processing via γ-secretase activation, but did not affect Notch processing. In addition, a cell-permeable Tat-OCIAD2 peptide that interfered with the interaction of OCIAD2 with nicastrin interrupted the γ-secretase-mediated AICD production. Finally, OCIAD2 expression was significantly elevated in the brain of AD patients and PDAPP mice. This study identifies OCIAD2 as a selective activator of γ-secretase to increase Aβ generation. 相似文献
74.
By use of 14-C label it was demonstrated that apparent binding of urea N to polyaldehyde starch was probably preceeded by hydrolysis to ammonium ion. Thus direct urea binding was not the mechanism through which ingested polyaldehyde starch might increase fecal N excretion in uremic patients. 相似文献
75.
Elisabeth Ramos-Rodríguez Pablo Flores Martínez João P. da Ponte 《Systemic Practice and Action Research》2017,30(1):85-102
Within research into the teaching profession, there are two main areas of interest, which have been thoroughly defined and consolidated: teacher’s knowledge and teacher’s professional development. This paper considers the latter area, and specifically sets out to define the concept of the reflective teacher and to show how we have applied this concept in our research. It aims at defining a more precise notion of teachers’ professional development linked to the concept of a reflective teacher, drawing on information from different interdisciplinary sources so as to frame the concept clearly. We discuss the conditions which determine the reflective teacher, and report on how these were put to use in a training course for practising teachers in which participants reflected on challenging episodes from their professional experience. We hope that clarifying this term will enable different educational agents (school teachers, teacher trainers or researchers) to have an informed view that can be interpreted and critiqued, and that it will also be of value to initial teacher training and to in-service courses. 相似文献
76.
A D'Hont F Denoeud JM Aury FC Baurens F Carreel O Garsmeur B Noel S Bocs G Droc M Rouard C Da Silva K Jabbari C Cardi J Poulain M Souquet K Labadie C Jourda J Lengellé M Rodier-Goud A Alberti M Bernard M Correa S Ayyampalayam MR Mckain J Leebens-Mack D Burgess M Freeling D Mbéguié-A-Mbéguié M Chabannes T Wicker O Panaud J Barbosa E Hribova P Heslop-Harrison R Habas R Rivallan P Francois C Poiron A Kilian D Burthia C Jenny F Bakry S Brown V Guignon G Kema M Dita C Waalwijk S Joseph A Dievart 《Nature》2012,488(7410):213-217
Bananas (Musa spp.), including dessert and cooking types, are giant perennial monocotyledonous herbs of the order Zingiberales, a sister group to the well-studied Poales, which include cereals. Bananas are vital for food security in many tropical and subtropical countries and the most popular fruit in industrialized countries. The Musa domestication process started some 7,000 years ago in Southeast Asia. It involved hybridizations between diverse species and subspecies, fostered by human migrations, and selection of diploid and triploid seedless, parthenocarpic hybrids thereafter widely dispersed by vegetative propagation. Half of the current production relies on somaclones derived from a single triploid genotype (Cavendish). Pests and diseases have gradually become adapted, representing an imminent danger for global banana production. Here we describe the draft sequence of the 523-megabase genome of a Musa acuminata doubled-haploid genotype, providing a crucial stepping-stone for genetic improvement of banana. We detected three rounds of whole-genome duplications in the Musa lineage, independently of those previously described in the Poales lineage and the one we detected in the Arecales lineage. This first monocotyledon high-continuity whole-genome sequence reported outside Poales represents an essential bridge for comparative genome analysis in plants. As such, it clarifies commelinid-monocotyledon phylogenetic relationships, reveals Poaceae-specific features and has led to the discovery of conserved non-coding sequences predating monocotyledon-eudicotyledon divergence. 相似文献
77.
78.
Functional hydrogel structures for autonomous flow control inside microfluidic channels 总被引:1,自引:0,他引:1
Hydrogels have been developed to respond to a wide variety of stimuli, but their use in macroscopic systems has been hindered by slow response times (diffusion being the rate-limiting factor governing the swelling process). However, there are many natural examples of chemically driven actuation that rely on short diffusion paths to produce a rapid response. It is therefore expected that scaling down hydrogel objects to the micrometre scale should greatly improve response times. At these scales, stimuli-responsive hydrogels could enhance the capabilities of microfluidic systems by allowing self-regulated flow control. Here we report the fabrication of active hydrogel components inside microchannels via direct photopatterning of a liquid phase. Our approach greatly simplifies system construction and assembly as the functional components are fabricated in situ, and the stimuli-responsive hydrogel components perform both sensing and actuation functions. We demonstrate significantly improved response times (less than 10 seconds) in hydrogel valves capable of autonomous control of local flow. 相似文献
79.
Zusammenfassung Die Permeabilitätsverhältnisse der Blut-Hirn-Schranke nach spezifischer Hemmung der 5-Nucleosid-Phosphatase wurden mittels Fluoreszenzmikroskopie studiert und eine Permeabilitätserhöhung nach Injektion von Nickelchlorid gefunden: Trypanblau kann dabei ins Gehirn penetrieren, was dafür spricht, dass die 5-Nucleosid-Phosphatase bei der Regulation der Kapillarpermeabilität eine bedeutende Rolle spielt. 相似文献
80.
Moreira MC Klur S Watanabe M Németh AH Le Ber I Moniz JC Tranchant C Aubourg P Tazir M Schöls L Pandolfo M Schulz JB Pouget J Calvas P Shizuka-Ikeda M Shoji M Tanaka M Izatt L Shaw CE M'Zahem A Dunne E Bomont P Benhassine T Bouslam N Stevanin G Brice A Guimarães J Mendonça P Barbot C Coutinho P Sequeiros J Dürr A Warter JM Koenig M 《Nature genetics》2004,36(3):225-227
Ataxia-ocular apraxia 2 (AOA2) was recently identified as a new autosomal recessive ataxia. We have now identified causative mutations in 15 families, which allows us to clinically define this entity by onset between 10 and 22 years, cerebellar atrophy, axonal sensorimotor neuropathy, oculomotor apraxia and elevated alpha-fetoprotein (AFP). Ten of the fifteen mutations cause premature termination of a large DEAxQ-box helicase, the human ortholog of yeast Sen1p, involved in RNA maturation and termination. 相似文献