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61.
ELISA LOBATO SANTIAGO MERINO JUDITH MORALES GUSTAVO TOMÁS JOSUÉ MARTÍNEZ‐DE LA PUENTE ESTRELLA SÁNCHEZ SONIA GARCÍA‐FRAILE JUAN MORENO 《Ibis》2008,150(4):799-806
Sex differences in immune function are relatively well studied in vertebrate animals, although the patterns are not always clear in birds. The study of immune responses in nestlings of wild bird populations may constitute an appropriate way to investigate inherent intersexual differences while controlling for environmental conditions such as parasitism that affect male and female individuals growing in the same nest. We studied whether the cell‐mediated immune response, as measured by phytohaemagglutinin (PHA) injection, and the levels of circulating antibodies differ between sexes of Pied Flycatcher nestlings Ficedula hypoleuca. No sex differences in nestling cell‐mediated immune response were found, but females showed significantly higher levels of plasma immunoglobulins than males did. Although nestling birds may not have a fully functional humoral immune defence, our study indicates that sex differences in the humoral component exist at this early stage of life. Given the importance of antibodies in the fight against parasite, bacterial and viral infections, the intrinsic sex disparity in circulating antibodies may have important implications for the life history of each sex. 相似文献
62.
Body condition‐dependent dispersal strategies are common in nature. Although it is obvious that environmental constraints may induce a positive relationship between body condition and dispersal, it is not clear whether positive body conditional dispersal strategies may evolve as a strategy in metapopulations. We have developed an individual‐based simulation model to investigate how body condition–dispersal reaction norms evolve in metapopulations that are characterized by different levels of environmental stochasticity and dispersal mortality. In the model, body condition is related to fecundity and determined either by environmental conditions during juvenile development (adult dispersal) or by those experienced by the mother (natal dispersal). Evolutionarily stable reaction norms strongly depend on metapopulation conditions: positive body condition dependency of dispersal evolved in metapopulation conditions with low levels of dispersal mortality and high levels of environmental stochasticity. Negative body condition‐dependent dispersal evolved in metapopulations with high dispersal mortality and low environmental stochasticity. The latter strategy is responsible for higher dispersal rates under kin competition when dispersal decisions are based on body condition reached at the adult life stage. The evolution of both positive and negative body condition‐dependent dispersal strategies is consequently likely in metapopulations and depends on the prevalent environmental conditions. 相似文献
63.
JESÚS MANZANILLA ENRIQUE LA MARCA MARIO GARCÍA-PARÍS 《Biological journal of the Linnean Society. Linnean Society of London》2009,97(1):185-199
We used partial sequences of mitochondrial 16S and cytochrome oxidase I genes to perform a phylogenetic study of collared frogs (Anura: Aromobatidae: Mannophryne ), a genus endemic to Venezuela and the islands of Trinidad and Tobago. We analysed 1.2 kb from 13 of the 15 described species of Mannophryne . Maximum parsimony, maximum likelihood and Bayesian analyses support the monophyly of Mannophryne . Mannophryne consists of three deeply differentiated clades that split from each other in a relatively short period of time. The diversification of Mannophryne occurred well before the glacial-interglacial periods of the Quaternary. Our data support the taxonomic validity of M. olmonae , a species endemic to Tobago Island. Mannophryne olmonae is more closely related to the continental species Mannophryne riveroi than to the Trinidad island endemic Mannophryne trinitatis . As in most tropical clades of frogs, molecular evidence indicates that species richness in Mannophryne is largely underestimated and, consequently, current priorities for conservation are inadequate. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 185–199. 相似文献
64.
MANUEL DE LA ESTRELLA CARLOS AEDO MAURICIO VELAYOS 《Botanical journal of the Linnean Society. Linnean Society of London》2009,159(2):268-279
A multivariate morphometric study of Daniellia, an endemic genus of tropical and subtropical Africa, indicates that nine species may be recognized: D. alsteeniana, D. klainei, D. oblonga, D. ogea, D. oliveri, D. pilosa, D. pynaertii, D. soyauxii and D. thurifera. In our study we found that some characters, not previously studied in detail, were significant in species delimitation: petiole indumentum, petiole width, number and position of glands on the lower surface of the leaflets and presence or absence of glands at the insertion of each pair of leaflets. The rare and scattered material of D. pilosa and D. soyauxii made their classification uncertain, although some qualitative characters support their differentiation. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 268–279. 相似文献
65.
Jan AM van Laar Jasper H Kappen Paul LA van Daele P Martin van Hagen 《Arthritis research & therapy》2009,11(2):109-3
Behçet's disease is a complex vasculitis of unknown etiology. Abundant neutrophils suggest the involvement of innate immunity. Cytokines are skewed to the T-helper-1 pattern. Few sterile organs are easily accessible for analysis in Behçet's disease. Cañete and coworkers identify inflamed joints as a feasible model and suggest the involvement of innate immunity in Behçet's disease. 相似文献
66.
MANUEL DE LA ESTRELLA FRANCISCO J. CABEZAS CARLOS AEDO MAURICIO VELAYOS 《Botanical journal of the Linnean Society. Linnean Society of London》2006,151(4):541-562
This study provides a checklist of the Caesalpinioideae (Leguminosae) present in Equatorial Guinea, comprising 52 genera and 124 taxa. Seven species are known from Annobón, 33 from Bioko and 109 from Río Muni. The best represented genus is Senna with eight species. In addition, bibliographic references for Caesalpinioideae (Leguminosae) from Equatorial Guinea have been gathered and checked. Fourteen species are included based on literature records, because their distribution ranges suggest they may occur in Equatorial Guinea, 11 introduced species could be naturalized, and 45 taxa are recorded for the first time from the country. This represents an increase of over 35% in the floristic knowledge of Caesalpinioideae from Equatorial Guinea. A statistical summary is presented at the end of the checklist. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 541–562. 相似文献
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本研究旨在探讨谷糠结合态多酚(bound phenol of inner shell,BPIS)发挥抗乳腺癌细胞活性的作用机制。首先采用细胞计数法检测BPIS对乳腺癌细胞以及正常乳腺细胞活性的影响;然后综合运用SEA、SIB以及GeneCards等数据库获得BPIS和乳腺癌的相关靶点,并分析活性成分与作用靶点的互作网络以及通路。本研究筛选得到BPIS抗乳腺癌相关靶点39个,主要涉及糖脂代谢和细胞自噬等生物过程以及MAPK、PI3K/AKT、FoxO等多条信号通,表明BPIS抗乳腺癌是多成分、多靶点、多通路协同作用的过程,而与细胞死亡相关的细胞自噬很可能在BPIS抑制乳腺癌过程中发挥主要作用。 相似文献
70.
研究抗肿瘤药阿霉素对Wnt通路抑制因子FrpHE(frizzled-related protein)和DKK-1(Dickkopf-1)表达的作用.将抗肿瘤药阿霉素加入到人肝癌HepG2(HepG2,含野生型p53;Hep3B,p53缺失)、人大肠癌(Lovo,含野生型p53)和人神经胶质瘤细胞(U251,p53突变)细胞株中.以RT-PCR技术检测阿霉素对Wnt通路抑制因子FrpHE和DKK-1的表达调节作用,以流式细胞术检测在肿瘤细胞中Wnt通路的关键调节因子β-catenin的表达.在加入阿霉素24h后FrpHEmRNA表达水平在人肝癌细胞(HepG2,含野生型p53;Hep3B,p53缺失)中与对照组相比表达水平显著增加.在人大肠癌细胞(Lovo,含野生型p53)和人神经胶质瘤细胞(U251,p53突变型)细胞中,未见FrpHE mRNA表达.DKK-1mRNA表达水平在人肝癌细胞(HepG2,含野生型p53;Hep3B,p53缺失)、人大肠癌细胞(Lovo,含野生型p53)和人神经胶质瘤细胞(U251,p53突变型)中与对照组相比表达水平显著增加.β-catenin的阳性细胞百分比强度和平均荧光量强度与对照组相比,表达水平降低.提示化疗药阿霉素能明显诱导抑制剂FrpHEmRNA和DKK-1mRNA的表达. 相似文献