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81.
E. C. R. Tavano L. C. L. Stipp F. R. Muniz F. A. A. Mour?o Filho B. M. J. Mendes 《Biologia Plantarum》2009,53(2):395-399
In vitro organogenesis of Citrus volkameriana and C. aurantium was studied considering three explant types: epicotyl segment, internodal segment, and hypocotyl segment with attached cotyledon
fragment. The explants were cultured in medium according to Grosser and Gmitter (EME) supplemented with 0, 0.5, 1.0, 1.5,
and 2.0 mg dm− 3 6-benzyl-aminopurine (BAP), incubated firstly in darkness for 4 weeks, and then transferred to 16-h photoperiod for 2 weeks.
Comparing epicotyl and internodal segments, a higher percentage of responsive explants and a higher number of shoots per explant
were obtained with epicotyl segments, regardless of the BAP concentration. For C. volkameriana the highest percentage of responsive epicotyl segments (42 %) was obtained in EME with 1.0 mg dm−3 BAP, while for C. aurantium (59 %) in EME with 0.5 mg dm−3 BAP. The organogenesis efficiency was the best with the use of the hypocotyl segment with attached cotyledon fragment (77
% for C. volkameriana and to 75 % for C. aurantium). With this explant the morphogenesis occurred only in the hypocotyl region. The in vitro organogenesis was characterized by histological analyses showing that the morphogenic process started in the cambium region
near the explant cut end. 相似文献
82.
Renato M Salgado Luciane P Capelo Rodolfo R Favaro Jocelyn D Glazier John D Aplin Telma MT Zorn 《Reproductive biology and endocrinology : RB&E》2009,7(1):60
Background
Remodeling of the extracellular matrix is one of the most striking features observed in the uterus during the estrous cycle and after hormone replacement. Versican (VER) is a hyaluronan-binding proteoglycan that undergoes RNA alternative splicing, generating four distinct isoforms. This study analyzed the synthesis and distribution of VER in mouse uterine tissues during the estrous cycle, in ovariectomized (OVX) animals and after 17beta-estradiol (E2) and medroxyprogesterone (MPA) treatments, either alone or in combination. 相似文献83.
84.
Extension of the core map of common bean with EST-SSR,RGA, AFLP,and putative functional markers 总被引:1,自引:0,他引:1
Luiz Ricardo Hanai Luciane Santini Luis Eduardo Aranha Camargo Maria Helena Pelegrinelli Fungaro Paul Gepts Siu Mui Tsai Maria Lucia Carneiro Vieira 《Molecular breeding : new strategies in plant improvement》2010,25(1):25-45
Microsatellites and gene-derived markers are still underrepresented in the core molecular linkage map of common bean compared
to other types of markers. In order to increase the density of the core map, a set of new markers were developed and mapped
onto the RIL population derived from the ‘BAT93’ × ‘Jalo EEP558’ cross. The EST-SSR markers were first characterized using
a set of 24 bean inbred lines. On average, the polymorphism information content was 0.40 and the mean number of alleles per
locus was 2.7. In addition, AFLP and RGA markers based on the NBS-profiling method were developed and a subset of the mapped
RGA was sequenced. With the integration of 282 new markers into the common bean core map, we were able to place markers with
putative known function in some existing gaps including regions with QTL for resistance to anthracnose and rust. The distribution
of the markers over 11 linkage groups is discussed and a newer version of the common bean core linkage map is proposed. 相似文献
85.
86.
Citrus aurantium L. is popularly used to treat anxiety, among other indications suggesting central nervous system action. Previous studies showed anxiolytic effect in the essential oil from peel in mice evaluated on the elevated plus maze [Carvalho-Freitas, M.I.R., Costa, M., 2002. Anxiolytic and sedative effects of extracts and essential oil from Citrus aurantium L. Biological and Pharmaceutical Bulletin 25, 1629-1633.]. In order to better characterize the activity of the essential oil, it was evaluated in two other experimental models: the light-dark box and the marble-burying test, respectively related to generalized anxiety disorder and to obsessive compulsive disorder. Mice were treated acutely by oral route 30 min (single dose) or once a day for 15 days (repeated doses) before experimental procedures. In light-dark box test, single treatment with essential oil augmented the time spent by mice in the light chamber and the number of transitions between the two compartments. There were no observed alterations in the parameters evaluated in light-dark box after repeated treatment. Otherwise, single and repeated treatments with essential oil were able to suppress marble-burying behavior. At effective doses in the behavioral tests, mice showed no impairment on rotarod procedure after both single and repeated treatments with essential oil, denoting absence of motor deficit. Results observed in marble-burying test, related to obsessive compulsive disorder, appear more consistent than those observed in light-dark box. 相似文献
87.
Luciano Pamplona de Góes Cavalcanti Lia Alves Martins Mota Gustavo Porto Lustosa Mayara Carvalho Fortes Davi Alves Martins Mota Ant?nio Afonso Bezerra Lima Ivo Castelo Branco Coelho Maria Paula Gomes Mour?o 《Memórias do Instituto Oswaldo Cruz》2014,109(1):93-98
In 2009, the World Health Organization (WHO) issued a new guideline that stratifies
dengue-affected patients into severe (SD) and non-severe dengue (NSD) (with or
without warning signs). To evaluate the new recommendations, we completed a
retrospective cross-sectional study of the dengue haemorrhagic fever (DHF) cases
reported during an outbreak in 2011 in northeastern Brazil. We investigated 84
suspected DHF patients, including 45 (53.6%) males and 39 (46.4%) females. The ages
of the patients ranged from five-83 years and the median age was 29. According to the
DHF/dengue shock syndrome classification, 53 (63.1%) patients were classified as
having dengue fever and 31 (36.9%) as having DHF. According to the 2009 WHO
classification, 32 (38.1%) patients were grouped as having NSD [4 (4.8%) without
warning signs and 28 (33.3%) with warning signs] and 52 (61.9%) as having SD. A
better performance of the revised classification in the detection of severe clinical
manifestations allows for an improved detection of patients with SD and may reduce
deaths. The revised classification will not only facilitate effective screening and
patient management, but will also enable the collection of standardised surveillance
data for future epidemiological and clinical studies. 相似文献
88.
Ciapina LP Picchi SC Lacroix JM Lemos EG Ödberg-Ferragut C 《Canadian journal of microbiology》2011,57(2):149-154
The twin-arginine translocation (Tat) pathway of the xylem-limited phytopathogenic bacterium Xylella fastidiosa strain 9a5c, responsible for citrus variegated chlorosis, was explored. The presence of tatA, tatB, and tatC in the X. fastidiosa genome together with a list of proteins harboring 2 consecutive arginines in their signal peptides suggested the presence of a Tat pathway. The functional Tat dependence of X. fastidiosa OpgD was examined. Native or mutated signal peptides were fused to the β-lactamase. Expression of fusion with intact signal peptides mediated high resistance to ampicillin in Escherichia coli tat+ but not in the E. coli tat null mutant. The replacement of the 2 arginines by 2 lysines prevented the export of β-lactamase in E. coli tat+, demonstrating that X. fastidiosa OpgD carries a signal peptide capable of engaging the E. coli Tat machinery. RT-PCR analysis revealed that the tat genes are transcribed as a single operon. tatA, tatB, and tatC genes were cloned. Complementation assays in E. coli devoid of all Tat or TatC components were unsuccessful, whereas X. fastidiosa Tat components led to a functional Tat translocase in E. coli TatB-deficient strain. Additional experiments implicated that X. fastidiosa TatB component could form a functional heterologous complex with the E. coli TatC component. 相似文献
89.
Séverin S Pollitt AY Navarro-Nuñez L Nash CA Mourão-Sá D Eble JA Senis YA Watson SP 《The Journal of biological chemistry》2011,286(6):4107-4116
The C-type lectin-like receptor CLEC-2 signals via phosphorylation of a single cytoplasmic YXXL sequence known as a hem-immunoreceptor tyrosine-based activation motif (hemITAM). In this study, we show that phosphorylation of CLEC-2 by the snake toxin rhodocytin is abolished in the absence of the tyrosine kinase Syk but is not altered in the absence of the major platelet Src family kinases, Fyn, Lyn, and Src, or the tyrosine phosphatase CD148, which regulates the basal activity of Src family kinases. Further, phosphorylation of CLEC-2 by rhodocytin is not altered in the presence of the Src family kinase inhibitor PP2, even though PLCγ2 phosphorylation and platelet activation are abolished. A similar dependence of phosphorylation of CLEC-2 on Syk is also seen in response to stimulation by an IgG mAb to CLEC-2, although interestingly CLEC-2 phosphorylation is also reduced in the absence of Lyn. These results provide the first definitive evidence that Syk mediates phosphorylation of the CLEC-2 hemITAM receptor with Src family kinases playing a critical role further downstream through the regulation of Syk and other effector proteins, providing a new paradigm in signaling by YXXL-containing receptors. 相似文献
90.
André Rodrigues de Souza Luiza Carla Barbosa Martins Carlos Alberto Mourão-Júnior José Eduardo Serrão José Lino-Neto 《Journal of Insect Behavior》2014,27(2):251-256
Individual recognition (IR) has been demonstrated in some Pachycondyla ants. The maintenance of such memories is challenged when queens are separated for the few hours of forage (attenuation) or when they are simultaneously interacting with conspecifics in a reduced space, that is, the nest (interference). By quantifying the level of aggression among familiar and unfamiliar queens of P. inversa, we showed that memories of social partner’s identity are robust to attenuation over the course of 2 days and to interference from subsequent interaction with five other individuals. Because wasps and crabs also remember familiar partners after separation and interaction with other conspecifics, we propose that robustness of social memories is widespread in invertebrates with IR abilities. 相似文献